On the Shoulders of Titans
A History of Project Gemini
Barton C. Hacker
James M. Grimwood
Published as NASA Special Publication-4203 in the NASA History Series, 1977.
Page numbers from the original publication are included within the text within square brackets.
Very special thanks to David Woods for formatting this on-line version and to Chris Gamble for proofreading.
Table of Contents
Mt. Godwin-Austen (K-2) (S65-45648)
The Nile (S65-34780)
Rub-al-Khali, Arabia (S65-34765)
Cordillera Blanca, Peru (S66-38298)
Medina, Saudi Arabia (S65-34665)
Arabian Peninsula & Gulf of Oman (S65-34661)
Eastern Sahara (S66-54525)
Air-Au-Azbine Mountains, Niger (S65-63158)
Algerian Sahara (S65-63829)
Baja California (S65-45586)
Sinai & Middle East (S66-54893)
Texas-Louisiana Gulf Coast (S66-63032)
Taiwan & Formosa Strait (S66-45868)
Florida Keys (S65-34766)
Sunset over Andes (S65-63780)
Southern tip of India (S66-54676)
Namib Desert and Atlantic Coast (S65-45579)
Circular Feature in Sahara (S65-34670)
Vortex off Moroccan Coast (S65-45665)
Cape Canaveral, Florida (S65-45599)
Ethiopian Lakes (S65-63162)
Colorado River (S65-34673)
South-central Iran (S65-45720)
Yangtze River, China (S65-45713)
Nile Delta (S65-34776)
South Yemen (S65-34658)
Oued Saoura, Algerian Sahara (S65-63830)
Cairo and Nile Delta (S65-45778)
Edwards Plateau (S65-34704)
[v]GEMINI was the intermediate manned space flight program between America's first steps into space with Mercury and the amazing and unprecedented accomplishments achieved during the manned lunar expeditions of Apollo. Because of its position between these two other efforts, Gemini is probably less remembered. Still, it more than had its place in man's progress into this new frontier.
Gemini accomplishments were manyfold. They included many firsts: first astronaut-controlled maneuvering in space; first rendezvous in space of one spacecraft with another; first docking of one spacecraft with a propulsive stage and use of that stage to transfer man to high altitude; first traverse of man into the Earth's radiation belts; first extended manned flights of a week or more in duration; first extended stays of man outside his spacecraft; first controlled reentry and precision landing; and many more.
These achievements were significant in ways one cannot truly evaluate even today, but two things stand out: (1) it was the time when America caught up and surpassed the Soviet Union in manned space flight, and (2) these demonstrations of capability were an absolute prerequisite to the phenomenal Apollo accomplishments then yet to come.
America's first manned space flight program, Mercury, involved a careful buildup of flight duration to slightly beyond one day with accompanying concerns about man's physiological response to weightlessness and other aspects of his safety and well being. In the meantime, the Russian effort had achieved durations of five days, flight of a multiple crew shortly after the Mercury Program had terminated, and the first extravehicular operation by a cosmonaut shortly before the first manned Gemini flight. The question at that time was who would perform the first rendezvous, seen as a very complex operation but absolutely needed for future space endeavors.
[vi]About the time Gemini started, the Russian effort slowed down as they attempted to develop and flight qualify their second-generation manned spacecraft, Soyuz. In the meantime, Gemini, America's second-generation spacecraft, reeled off ten manned flights in less than twenty months - a flight rate yet to be surpassed in any space program. The last five manned launches were accompanied by nearly simultaneous and precisely timed launches of rendezvous target vehicles. During this period, rendezvous demonstrations and many other activities took place which were not to be matched by corresponding Soviet accomplishments for years to come, and more than five years passed before the two-week long mission of Gemini VII was exceeded by the Russians with their Salyut spacecraft.
However, these Gemini mission spectaculars were not aimed at "beating the Russians"; rather, their purpose was to support and demonstrate needed mission capability for the upcoming Apollo flights to the Moon. Apollo needed a reliable rendezvous and docking operation if the astronauts were to get back from the Moon. Could this be done? Gemini demonstrated such a capability with great success six straight times and with many different techniques. The Apollo missions required a duration of a week or two. Could this be done? Gemini demonstrated mission durations of one and two weeks with no major untoward effects on the astronauts. The Apollo astronauts would spend hours outside their spacecraft exploring the lunar surface. Could this be done? Of the five EVA missions conducted in Gemini, four of them lasted from two to four hours. Tired astronauts returning from the Moon would want to land as close as possible to the recovery aircraft carrier. Could this be done? Indeed, it was accomplished seven straight times during the last two-thirds of the Gemini Program. Apollo needed to develop advanced reliable systems. Could this be done? Their names probably still sound strange to many, but fuel cells, cryogenic storage of hydrogen and oxygen, ablative thrusters using hypergolic propellants, an onboard digital computer, an inertial guidance system, and a rendezvous radar were developed and demonstrated in Gemini. One must admit to considerable difficulty in these developments, but, in the end, they provided a high degree of confidence that systems embodying high reliability could be obtained.
Equally important to Apollo was the training provided by the Gemini missions to the flight and ground crews. The mission control center techniques and the flight control team procedures were largely implemented during Gemini. Of the astronaut complement assigned to the first four flights to the Moon, ten of the twelve had prior Gemini flight experience and the other two had been members of Gemini backup crews. In all, over half of the Apollo crew members had direct Gemini flight experience.
[vii]Gemini also carried forward a major experiment program in space science and applications. Over 50 such experiments were carried out involving astronomy, biology, atmospheric sciences, medicine, radiation effects, micrometeoroid investigations, space environmental effects, and others. Technical and operational experimentation involved such things as low light level TV observations, special photography, special communications tests, tethering of two vehicles, and gravity gradient stabilization. The hundreds of synoptic weather and Earth terrain color photographs taken contributed greatly to the development of the meteorological and Earth resources programs which are now bringing important benefits from rapid global observations of the Earth to people here on the surface. Lest one think that the Gemini flights were carried forward with great smoothness, be assured that most of them encountered real cliff-hanging incidents. On Gemini IV, the astronauts had great difficulty in closing the hatch after their EVA which was accomplished only after great physical exertion and almost complete exhaustion. Needless to say, corrections were made before the next flight. Gemini V, which was planned to fly for eight days, was almost called back after a few hours because of loss of pressure in the cryogenic tanks supplying fuel for the new electrical power devices called fuel cells. But the crew and flight controllers nursed the spacecraft along for the full mission duration by powering down the spacecraft and using just a few watts of electrical power. Their problems were compounded when some of the attitude stabilization rockets failed late in the mission.
After loss of the first rendezvous target vehicle, caused by an explosion during launch, Gemini VI and VII were reconfigured so that Gemini VII served as the rendezvous target for Gemini VI in the "Spirit of 76" mission just before Christmas in 1965, after which Gemini VII continued to struggle along with balky fuel cells for a record duration of 14 days in space. Gemini VIII spun out of control just after accomplishing the first docking in space. The crew was able to correct this condition in spite of rotating nearly one revolution every second. But the spacecraft had to be returned to Earth rapidly and landed in the western Pacific Ocean. Astronauts became exhausted from EVA exertions on Gemini IX and XI. Only the last mission, Gemini XII, (and perhaps Gemini X) could be called really smooth, carried out pretty much as planned.
In spite of all these exciting mission events, problems, and accomplishments, the thing that stands out in my own mind is the way in which the effort and dedication of many individuals and groups coalesced into an extremely effective team. This cliche is often voiced whenever an activity is successful, but, in Gemini, the observed capacity for accomplishment proved to be well beyond a program manager's most optimistic hopes. Although not so visible from a program manager's level, this cooperation and support had to extend to the level of the NASA Administrator and his [viii] interfaces with the President, congressional leaders, heads of other agencies, industry, and the Public in general. Most certainly, this same situation occurred during the Apollo Program and, no doubt, has occurred in connection with most major achievements of man. However, Gemini - though a complex undertaking - was small enough for this to stand out very clearly. Such an experience leads one to believe that man can accomplish almost anything if sufficient dedication and cooperation exists between and within the groups involved. In Gemini, this esprit de corps was actually enhanced by the mistakes made or the problems encountered because of the positive approach to dealing with them. A prime example of this occurred when a critical hydraulic system failed on the launch vehicle just at engine start prior to liftoff on the first full systems test of Gemini. The response of the people involved was truly outstanding. Even though recovery from this problem involved trying work over the Christmas holidays, everyone involved put forward a maximum effort, including the small job shop that built a new casting, the hydraulic valve contractor, the prime contractor, the Air Force, its support contractors, and NASA. As a result of such effort, the cause of the failure was isolated, a completely new component designed, built, tested, qualified, installed, and checked out so that a second attempt could be made only six weeks after this major difficulty occurred. There may have been evidences of parochialism and vested interests early in the programs but after an event and accomplishment such as that, the whole team concentrated on the program in the spirit of an elite group.
I believe that this is a lesson and a legacy that our space programs have left to future generations just as other eras of great accomplishment have done. Admittedly, Mercury, Gemini, and Apollo had very clear objectives. But even in more complex and confusing situations an integrated and dedicated striving to solutions of problems would seem to be an approach well worth taking. In today's world, there seems to be an undue degree of second-guessing and lack of cooperation in many endeavors. Gemini was far from perfect, but, although its people recognized and encountered imperfections they strove as a group for perfection.
Charles W. Mathews
Associate Administrator for Applications
[xv] PROJECT Gemini is now little remembered, having vanished into that special limbo reserved for the successful intermediate steps in a fast-moving technological advance. Conceived and approved in 1961, the second major project in the American manned space flight program carried men into orbit in 1965 and 1966. Gemini thus kept Americans in space between the path-breaking but limited Earth-orbital missions of Project Mercury and the far more ambitious Project Apollo, which climaxed in 1969 when two men first set foot on the Moon. Although keeping the nation in space was one of the motives that induced the National Aeronautics and Space Administration (NASA) to go ahead with Project Gemini, it was not the overriding one. It furnished the setting in which a new project could be approved, but the precise character of that project grew out of two distinct lines of development that converged during 1961.
President John F. Kennedy's decision in May 1961 to commit the United States to landing on the Moon before the end of the decade gave Gemini its central objective. NASA planners had been thinking about the Moon, an obvious goal for manned space flight, almost from the moment the agency itself was created in 1958. The Moon, however, was seen as a target for the 1970s, pending development of a huge rocket, called Nova. It would launch a spacecraft that would fly directly to the Moon, land there, and then return. This direct approach was widely accepted on the grounds that it was almost certain to work.
Some NASA engineers had advocated an alternative method, in which two or more spacecraft might rendezvous in orbit rather than proceed directly to the Moon. This approach promised enormous savings in fuel and weight; the lunar mission based on rendezvous might be launched with much smaller rockets, and therefore much sooner, than the direct mission. [xvi] The greatest drawback of this approach was its novelty. No one knew how hard a rendezvous in space might be. So long as time was ample, the direct method offered by far the safer prospect. When the President imposed a deadline, however, support for rendezvous waxed. It promised a quicker and cheaper road to the Moon, if it could be achieved. The "If" was a big one in 1961, big enough to justify the expense of a full-fledged manned space flight project to resolve it. Gemini was first and foremost a project to develop and prove equipment and techniques for rendezvous.
That the project turned out to be Gemini, however, rather than something else, resulted from a second distinct chain of causes. Government and industry engineers who worked in Project Mercury saw innumerable ways to improve their product. Constrained by the limited power of the Atlas rocket that launched Mercury, they had been forced to design a spacecraft with integrated systems; the inside of the capsule was crammed with layered components, filling every cranny and making it hard to build, hard to test, and hard to prepare for flight. As a first step it might do, but it could never be much more. Throughout 1959 and 1960, while the main effort centered on making Mercury work, thinking turned more and more to the kind of spacecraft that should come next; it should be based on the lessons learned in working on the essentially handcrafted, experimental machine that was Mercury, but modified to permit something more closely resembling routine building, testing, and operation than Mercury allowed. By mid-1961, these ideas coalesced into a concrete proposal for a new spacecraft, just when NASA was casting about for a means of working out the problems of rendezvous. Gemini's second taproot was an engineering concern to improve spacecraft technology beyond the first step that was Mercury.
Project Gemini owed its origins both to its predecessor - it built on the technology and experience of Project Mercury - and to its successor - it derived its chief justification from Project Apollo's concerns. The new project acquired other objectives as well: testing the concept of controlled landing, determining the effects of lengthy stays in space, and training ground and flight crews. The process through which a broad range of ideas and concerns came together in a clearly defined space flight program is the main theme of this book's first three chapters. By December 1961, when the new project received its formal stamp of approval from NASA Headquarters in Washington, much of the design work had been done, many of the major decisions had already been made. A Gemini Project Office at the Manned Spacecraft Center (renamed Lyndon B. Johnson Space Center in February 1973) in Houston took charge of overseeing the effort. Just a week after project approval, the first major contract went to McDonnell Aircraft Corporation [xvii] for the Gemini spacecraft. A separate contract with North American Aviation had already initiated work on the paraglider landing system that was intended to allow Gemini to alight on land rather than water. Other key contracts were soon awarded through the Air Force Space Systems Division for the project's several rocket boosters: to Martin Company for the Titan II to launch the spacecraft, to Lockheed Missiles & Space Company for the Agena to serve as rendezvous target, and to General Dynamics Corporation for the Atlas to boost Agena into space. A matter of months sufficed to erect the whole structure of contracts and subcontracts that united the efforts of government and industry in Project Gemini.
Gemini thus moved quickly into its development phase, the central effort of 1962 and 1963. It was an unsettled period, as such times always are for high-technology projects. Although Gemini, perhaps more than most such undertakings, rested on already tested technologies, it still strained the limits of the known at some points. Inevitably this produced problems not always easy to resolve, the more so since Gemini was bound by severe time constraints. It could not, whatever happened, be allowed to overlap or interfere with Project Apollo. In one major instance, the paraglider, answers could not be found in time, and that goal had to be dropped.
Gemini's difficulties in its first two years were not solely technical, nor were technical problems perhaps even the most pressing. Gemini labored under a sharply restricted budget. The project faced a severe financial crisis during its first year and lesser such crises throughout its life. Within NASA and without, Apollo and the trip to the Moon always held center stage. Gemini got more than crumbs - its final cost exceeded a billion dollars - but the margin remained narrow. More than once, lack of funds threatened the loss of one or another of its major goals, and money problems played a key role in managerial changes in 1963. That year, however, also saw Gemini's development completed, the worst of its technical problems (except the paraglider) resolved or clearly on the way to solution. Project Gemini's development troubles and their outcome provide the central thread for Chapters IV through VII.
By the end of 1963, Gemini was moving into its qualifying trials, which extended into 1965. The road was far from easy, but the worst was past, as reflected in the slow decline in the number of workers directly assigned to Gemini. Early 1964 saw the first of Gemini's 12 missions, an unmanned test of spacecraft and booster that was flawless. The long delay that followed was a reflection not on Gemini but on the Florida climate, as the launch site was buffeted by hurricanes. The second unmanned mission, in January 1965, proved that Gemini was ready to carry men aloft. Some two months later, Virgil I. Grissom and [xviii] John W. Young flew Gemini 3 through three circuits of Earth, and the project office set out after its planned goals. Gemini's qualification is the subject of Chapters VIII through X.
In striking contrast to the endless difficulties that had frustrated attempts to keep Project Mercury on schedule, Project Gemini came close to achieving a routine launch every other month throughout 1965 and 1966. Gemini XII closed out the program in November 1966. Gemini's operational phase was hardly so free of trouble as such a schedule might suggest, but the design that had been geared to easier testing and checkout proved its worth when coupled with the experience derived from earlier efforts. One by one, Gemini achieved its objectives, proving that astronauts could leave the shelter of their vehicle and function in space, that they could closely control spacecraft flight and landing, that they could survive up to two weeks in orbit without ill effects, and that they could rendezvous with a target in orbit. This is the story told in Chapters XI through XV.
The teams who serviced, flew, directed, and supported Gemini missions opened the near-space environment of Earth as a potential workshop and stilled some nagging fears about what might happen to men on the way to the Moon. They did not do it alone. Just as surely as the Gemini spacecraft rested on the shoulders of its Titan II launch vehicle, those who combined to make Project Gemini succeed stood on the shoulders of the giants who preceded them. Isaac Newton, who first formulated the laws of motion that Gemini applied in orbit three centuries later, wrote, "If I have seen farther, it is by standing on the shoulders of giants." So, too, did Project Gemini, not the least on those of Newton himself.
And so, too, did the authors of this history of Project Gemini: Barton C. Hacker, who wrote the first ten chapters on design, development, and qualification; and James M. Grimwood, who described operations in the last five chapters. Although this book will not be the last word on Gemini, we enjoyed an access to its documentary remains and to its participants not likely to be duplicated.
Aid in threading a path through this embarrassment of riches came from many sources at the Manned Spacecraft Center, elsewhere in NASA, other government agencies (especially the Air Force), the Gemini contractors, and others. Their numbers preclude individual thanks, but the authors gratefully acknowledge their help. Combing the records and interviewing the actors proved an arduous and challenging task. The contemporary historian must beware the sensitivities of the many people he writes about who are still very much alive. This may be especially true of a project so successful as Gemini proved to be, since the afterglow of accomplishment tends to dim memories of things that went wrong. Yet the advantage of having the counsel of the participants in weighing the mass of evidence more than compensates for any concomitant handicaps. [xix] They cheerfully endured lengthy interviews, cleared up technical points, ransacked their files, and commented on drafts.
This help was all the more important because Project Gemini never attracted as much attention as either Mercury or Apollo. Having neither the novelty of the first nor the enormously exciting goal of the second, Gemini prompted relatively little outside description or analysis. Journalistic interest was largely confined to Gemini's manned missions in 1965 and 1966, and even that coverage was slight after the first two. Never as high in public consciousness as Mercury or Apollo, Gemini now lives mainly in the memories of those who worked on it. This in part reflects Gemini's ambiguous status even within NASA - important to be sure but somehow outside the mainstream that flowed from Mercury to Apollo. Gemini seemed less touched by outside events than its brother programs. In writing its history, we have adopted what in the history of science is often called an internalist approach. The course of Gemini's history was clearly dictated by internal technical demands, and the focal point of the story is the work of the Gemini Program Office at the Manned Spacecraft Center. Picking out the particular individual whose contribution was unique is seldom possible, not because such contributions were lacking but because Gemini was so much a team effort. Many of those team members, both from government and from industry, have remarked on the sense of unity and elan they enjoyed in those days and have suggested that Gemini might have achieved a good deal more than it was called upon to do. However true that may be, Project Gemini, in terms of its actual costs, schedules, and performance, must rank among the most successful research and development projects ever conducted d by the United States.
We would like to extend special thanks to those whose efforts in behalf of this book significantly lightened our burdens. Sally D. Gates, Historical Office Archivist-Editor, served indispensably in a multitude of roles: research assistant, editor, coordinator of the comment draft, compiler of appendixes, typist, proofreader, and friendly critic. Billie D. Rowell and Corinne L. Morris, both of the Historical Office, at various times organized and managed the office's archives and performed a variety of other services. Jewell Norsworthy, Center records management officer, helped retrieve documents that had been retired to holding areas. Ivan D. Ertel, former Center assistant historian, and Peter J. Vorzimmer, former contract historian, conducted a number of interviews on behalf of the Gemini history. This book was written under the auspices of the NASA historical program through a contract with the History Department of the University of Houston; it has benefited from the advice and assistance of NASA historians Monte D. Wright, Frank W. Anderson, Jr., Eugene M. Emme, and William D. Putnam, as well as University of Houston professors James A. Tinsley and Loyd S. Swenson, Jr. [xx] Although it is officially sponsored, its authors alone must bear full responsibility for whatever defects it contains.
NOTE: NASA has placed itself in the forefront of the effort to convert the United States to the metric system. In 1973, use of all English weights and measures was prohibited in all NASA publications, including historical. This did present certain problems, since NASA engineers during the 1960 normally expressed themselves in feet, miles, pounds, etc. In general, where round figures are clearly intended, we have substituted round metric figures. Precise figures are converted precisely. For the reader's convenience, one metric unit requires a word of explanation. In the English system, "pound" is a unit of both mass and force, but the metric system is more rational and uses two distinct units: the familiar gram for mass, the less familiar newton for force - thus, for example, pounds of weight become grams, but pounds of thrust become newtons.
Between Mercury and Apollo
 In Houston, Texas, December temperatures in the low sixties seem cool.1 And so it must have seemed to Robert R. Gilruth when he landed in the city on 7 December 1961, especially in contrast to the muggy end-of-summer heat that had greeted him on his first visit two and a half months before. Gilruth's September visit had followed close on the heels of the announcement that the Space Task Group (STG) he headed was moving to Houston. With several of his colleagues, he had come to look over the new site for his fastgrowing branch of the National Aeronautics and Space Administration (NASA). Now he was back in Houston to tell the city's business community something about his group and its work - putting American astronauts into space and eventually landing them on the Moon. The occasion was what the Houston Chamber of Commerce billed, with a bit of Texas hyperbole, as its 121st annual meeting. True, a chamber of commerce had been formed in 1840, but it soon vanished without a trace. Seventy years later, the 15-year-old Houston Business League voted to rename itself the "Chamber of Commerce."2 Whether the 1961 session was the 121st, the 66th, or the 51st, it was still a big event. Houston "was a businessman's town."3
And it was a booming town, sprawling over more than 480 square kilometers (300 square miles) of Texas Gulf Coast "like a bucket of spilled water."4 In the same month that Gilruth first visited Houston, the city's population had passed the million mark. And that, according to the president of the Chamber of Commerce, was one of the "most significant milestones of Houston's progress in 1961."5  Houston and its people blended, not always smoothly, the South and the West. Chicanos joined blacks as part of the "problem" that sometimes troubled the ruling Anglos, who were "conservative, cautious, and business-oriented . . . because they reflect community attitudes."6 September 1961 was also the month when the first black pupils, twelve of them, entered Houston's white school system.7
But Houston's leaders, in a pattern that has marked American development at least since the 19th century, coupled social conservatism with economic opportunism. Founded as a lucky real-estate venture, the city had grown by exploiting the resources of a vast hinterland. Freewheeling promotion was, and remained, the order of the day, and nowhere more so than in the multibillion-dollar oil industry that Houston headquartered.8 The hotel to which Gilruth repaired was a perfect symbol of the city and a fitting site for the "121st" annual meeting of the Chamber of Commerce. Brainchild of Glenn McCarthy - oil millionaire, land speculator, and all-round promoter - the Shamrock Hotel had taken five years to build and cost $21 million. It opened grandly on St. Patrick's Day 1949, with 50,000 people gathered to eat $42-a-plate dinners. Six shades of green garnished its outer walls, a prospect otherwise so dull that Frank Lloyd Wright refused to comment on it, though glimpsing the interior did move him to muse, "I always wondered what the inside of a juke box looked like." McCarthy lost the hotel when his oil empire collapsed five years later, and it ended up in the hands of another Texas entrepreneur, Conrad Hilton. So it was the Shamrock Hilton, with Hilton's portrait gracing the lobby instead of McCarthy's, when Gilruth arrived.9
Gilruth himself symbolized another of the "milestones of Houston's progress in 1961." On 19 September, just a day after the city officially topped a million, NASA had announced its choice for the site of a new multimillion-dollar manned space flight laboratory.10 It was to be near Clear Lake, some 32 kilometers southeast of the city on a tract of land donated by the Humble Oil and Refining Company. This, too, fit the pattern of Houston's growth, at least since World War I, as federal funds had begun to flow into the city like the oil that much of that money financed. The president of the Chamber of Commerce welcomed NASA's new move as "one of the Houston's most meaningful developments since the opening of the Ship Channel for deep sea shipping in 1915." Gilruth directed the new facility, the Manned Spacecraft Center (MSC), which came officially into being on 1 November l96l.11
The Center was, in fact, merely the renamed Space Task Group (STG), created in 1958 to put Americans in space via Project Mercury. So far, STG had managed to loop two astronauts over the fringes of the atmosphere on Redstone boosters and to orbit with an Atlas rocket a chimpanzee named Enos. But the much-delayed attempt to orbit a man still receded.  On the same day that Gilruth spoke to the Houston Chamber of Commerce, he announced that the scheduled 19 December launch of Mercury-Atlas 6, with John H. Glenn, Jr., aboard, was now postponed until 1962. The United States was not going to match, at least in the same year, the Soviet Union's feat of sending a man into orbit. Nonetheless, optimism prevailed. The causes of the delay were minor, and success seemed just around the corner.12
STG, like Houston, had boomed in 1961. Two largely successful manned suborbital flights, followed by Mercury-Atlas 4 with its "mechanical man" and the ape-bearing Mercury-Atlas 5, had eased the worries caused by Mercury's technical problems during 1960. In the meantime, STG had added the manned lunar landing program, Project Apollo, to its responsibilities. It had outgrown its makeshift facilities at Langley Research Center in Virginia and its old name as well. After a painstaking search, NASA settled on Houston for STG's new location and soon furnished the group with a new name to match its larger role.13
For Houston, it was love at first sight, but the 750 NASA workers faced with moving 2,400 kilometers from Tidewater Virginia to Gulf Coast Texas in the midst of Project Mercury were less enthusiastic. Gilruth himself had qualms after his first view of the new site in September, shortly after it had been swept by Hurricane Carla.14 The decision had been made, however, and the space fever that promptly seized Houston helped smooth the changeover. A crowd of some 900 greeted Gilruth with a standing ovation when he stepped to the dais at the Shamrock Hilton to begin his remarks.15
What Gilruth had to say turned out to be headline news and earned him another standing ovation when he finished. NASA, he revealed, planned to launch a third manned space flight program to fill the gap between Mercury and Apollo. He outlined a half-billion dollar project to orbit a two-man Mercury capsule via the Air Force's new Titan II booster. The key goal was to develop orbital rendezvous, a novel technique NASA planned to use in the Apollo mission to the Moon. Once in orbit, the crewmen would steer their rocket-powered craft to a meeting with an unmanned Agena spacecraft, boosted into orbit separately by an Atlas.16 Gilruth had learned only that day of NASA Headquarters' approval of the new project.17 Still something of a puzzle was what to call it. In making it public, Gilruth labeled it a "two-man Mercury." Inside NASA, at one time or another, it had gone by the name of Advanced Mercury, Mercury Mark II (the one-man capsule being Mark I), or simply Mark II. Within three months, however, an ad hoc "program-naming" committee in NASA Headquarters decided on "Gemini" for the new project. Recognition for having picked that name, along with a bottle of scotch as prize, went to Alex P. Nagy in NASA Headquarters.  Gemini, "The Twins," was one of the 12 constellations of the zodiac. Nagy thought that "'the Twins' seems to carry out the thought nicely, of a two-man crew, a rendezvous mission, and its relation to Mercury. Even the astronomical symbol (II) fits the former Mark II designation."18 [GRAPHIC HERE]
By an unlikely coincidence, since Nagy disclaims any knowledge of astrology, Gemini as a sign of the zodiac is controlled by Mercury. Its spheres of influence include adaptability and mobility - two features  the spacecraft designers had explicitly pursued - and, through its link with the third house of the zodiac, all means of communication and transportation as well. Astrologically, at least, Gemini was a remarkably apt name, the more so since the United States is said to be very much under its influence.19 To those with no more than a passing knowledge of astrology, however, Gemini must have seemed a most obscure choice. To this day, its proper pronunciation has not been settled in NASA. Although an informal survey of astronomical opinion came down on the side of a terminal "ee" sound, many still opt for "eye."20 The new program publicly became Project Gemini on 3 January 1962.21
The Background of Rendezvous
The project that Gilruth announced on 7 December 1961 had not just then sprung into being. A year of planning, work, and advocacy had gone before, and more than three years of intense effort lay ahead before Gemini carried men into space. Even so, Gemini was something of an afterthought in the American manned space flight program. Gemini did fly after Mercury had achieved its major goal of putting an American into orbit and bringing him back safely and before Apollo first bore men aloft on the path that led eventually to the surface of the Moon. But that is misleading. One of the reasons for Gemini, in fact, was to keep Americans in space during the time when Mercury had run its course but Apollo had yet to be launched.
Gemini took shape after Apollo had begun, in part to answer a crucial question for Apollo: Was rendezvous and docking in orbit a feasible basis for a manned lunar landing mission? When NASA officials appeared before Congress early in 1962 to justify the new program, the heart of the case they argued was the need to develop and prove the techniques of orbital rendezvous.22 Project Gemini was intended to show that a piloted spacecraft could meet an unmanned target in space - the orbit of the spacecraft matching that of the target so that there was no significant difference in speed and no significant distance between the two, in much the same way that two aircraft might fly in formation.
Many aspects of modern space flight were first suggested in the sometimes fanciful but often profound space-travel writings of the early 20th century. One was the value of rendezvous in orbit. It first emerged as part of the space-station concept, which can be traced through the works of the Russian pioneers of astronautics - K. E. Tsiolkovskii, Yu. V. Kondratyuk, and F. A. Tsander - and in the writings of their Central European counterparts - Hermann Oberth, Walter Hohmann, Guido von Pirquet, and "Hermann Noordung." Their goal was flight to the Moon and planets, but their calculations suggested  that chemically propelled rockets might lack the power to launch such journeys directly from Earth's surface. If a journey were carried out in stages, however, the problem might be surmounted.
They proposed using a space station, a stopover point in orbit. Once such a station was built, any number of rockets might be launched to meet it, each bearing its cargo of fuel or supplies to be transferred to the station. When enough had been gathered, fuel and supplies might then be loaded aboard an interplanetary vessel, perhaps itself constructed in orbit, and the real journey to the planets could begin. In effect, the trip would be launched from orbit, the greater part of the velocity needed to escape Earth's gravitational field having been already attained. This concept had been widely accepted in space-travel circles by 1929.23
While rendezvous was clearly a key technique in this scheme, it failed to receive any special emphasis. That changed after 1949, when two members of the British Interplanetary Society pointed out that orbital staging need not depend on first building a space station. The new concept was called "orbital technique" or "orbital operations." The pieces of an interplanetary vessel might simply be assembled in Earth orbit without troubling to construct a space station, or several rockets might meet in orbit and transfer their fuel to one of their number, which would then embark on the final mission.24 As Wernher von Braun, later one of NASA's leading advocates of orbital operations, remarked, the space station really amounted to no more than a "space rigger's hotel."25
The rapid spread of this idea brought rendezvous into sharp focus. Unlike the space-station concept, to which rendezvous was a sometimes neglected adjunct, orbital operations moved rendezvous to center stage. The first paper specifically addressed to the problem of "Establishing Contact Between Orbiting Vehicles" appeared in 1951.26 One result was a renewed attention to orbital mechanics, a topic that had languished since the path-breaking work of Walter Hohmann in 1925. By the end of the 1950s, a theoretical framework for rendezvous techniques had been largely erected.27
When NASA planners began to grapple with the problem of picking long-range goals for the American space program, however, they tended to overlook the part rendezvous might play except as it related to space stations. This may have reflected, as much as anything else, the imprint on NASA of the National Advisory Committee for Aeronautics (NACA). When NASA began its career on 1 October 1958, its core was the 43-year-old NACA, to which had been added several military and quasi-military space projects. NASA was designed to be, and in time became, something larger, wealthier, and more adventurous than NACA had been. But for a time much remained unchanged or changed only slowly.  The habits of mind, the viewpoints, the styles, the biases fostered by the old setting did not vanish overnight with the old name. The same NACA engineers, scientists, managers, and technicians who left work on 30 September 1958 were back on the job for NASA the next morning. Time would bring new faces and fresh view-points, thin the ranks of the old NACA hands, and weaken the grip of old habits; but NACA left an enduring mark on NASA and its programs.28
NACA had existed to serve - to solve problems for military and industrial aircraft programs. Its field, in which it was very good, was applied research - solving general engineering and technical problems in aeronautics. NACA laboratories had produced many of the technological innovations that transformed the post-World War I airplane, a slow and inefficient machine of small military and no commercial importance, into the major weapon and economic giant of mid-century. Langley Memorial Laboratory was the first and, until the eve of World War II, the only NACA laboratory; Langley research pioneered many prewar innovations in aeronautical design. Lewis Flight Propulsion Laboratory and Ames Aeronautical Laboratory went into operation early in the Second World War, the Pilotless Aircraft Station in 1945, and the High Speed Flight Station in 1947. In 1940, NACA had 650 employees and a budget of $4.37 million; five years later it employed 6,800 and spent $40.5 million. But NACA still focused its research in those areas where lack of knowledge hindered aviation progress, spending little effort on basic research - expanding scientific knowledge - and steering clear of development, which meant seeing a specific project through design, building, and testing.29
During the 1950s, some of the most pressing problems in aeronautics arose from the little studied and poorly understood effects of high temperatures on very fast-moving aircraft and rockets. This made the focus of NACA research in that decade transonic and hypersonic flight, with special stress on aerodynamic heating phenomena.30 When Sputnik I on 4 October 1957 transformed space from a region of scientific curiosity to an arena for national rivalry and spurred planning for manned space flight, this background stood NACA in good stead.
A small group of engineers at Langley began working informally on a manned orbital satellite. At the start of October 1958, in one of his opening moves as NASA's first Administrator, T. Keith Glennan approved the project. He formed the Space Task Group to run it and announced its name as Mercury two months later. STG started with 45 people led by Robert Gilruth and they had only one job: the most direct and speedy achievement of manned orbital flights.31 It was a complex but straightforward engineering task. Project Mercury "did not require and does not require any major technological breakthroughs."32 What it did need was just what a NACA background provided,  the skills of applied research and aeronautical engineering and particularly experience in the aerodynamics of hypersonic flight.
Manned space flight beyond Mercury, however, was another matter. The crucial role of boosters in setting the limits of what could be done in space prompted NASA to its first long-range planning venture, "A National Space Vehicle Program," issued in January 1959.33 This report surveyed existing boosters and proposed developing a series of new ones. It did no more than suggest a range of missions suited to each of them. What could be done, however, was one thing; what should or would be done was something else. Choosing among the possible goals now became NASA's central planning concern.
This concern produced "The Ten Year Plan of the National Aeronautics and Space Administration" in December 1959. Ultimately spacecraft would carry explorers to the Moon and planets, but for the 1960s, NASA chose the more modest goal of circumlunar flight - a trip to the Moon, a few passes in orbit, and a return to Earth. "Manned exploration of the moon and the nearer planets must remain as major goals for the ensuing decade."34
NASA planners assumed that a trip to the Moon would be launched directly from Earth's surface. That required the giant Nova booster, the largest of the four new vehicles proposed in January 1959. Nova was a concept built on an engine (the F-1) designed to produce 6.7 meganewtons (1.5 million pounds of thrust). Air Force contracts with Rocketdyne had begun F-1 development in mid-1958. This was one of the military projects turned over to NASA when it was formed. Four of these engines were planned for Nova's first stage to provide 27 meganewtons (6 million pounds of thrust) at a time when the most powerful existing American booster required three engines to generate 1.6 meganewtons (360,000 pounds of thrust).35 The belief expressed in the January report that, "with Nova, a manned lunar landing first becomes possible,"36 pervaded NASA planning throughout 1959 and 1960. Even when refueling or assembly in orbit were discussed as alternatives worthy of study, they were discarded as a basis for planning, since "it is assumed that the Nova approach will be followed."37
The choice was by no means final, but NASA was leaning strongly toward direct ascent, perhaps more by default than by decision. To the extent that they had been compared at all, the merits of direct ascent and orbital operations had been merely asserted rather than studied. The question had been cited as a major one, and some of the problems involved in "the all-the-way approach versus the assembly-in-orbit approach" had been aired at meetings of the Research Steering Committee on Manned Space Flight, more commonly known as the Goett Committee after its chairman, Harry J. Goett of Ames, during 1959.* 38  But, as NASA's 10-year plan showed, the question had yet to exert much effect on NASA policy.
Notably absent from NASA's budget request for fiscal year 1961 was money to study rendezvous, nor did NASA spokesmen mention rendezvous when they defended the budget before Congress early in 1960.39 There was also little talk of space stations. That had not been true the year before, when NASA asked for funds to study both a small orbiting space laboratory and rendezvous techniques. These were closely related. NASA's 1959 choice of lunar landing over a space station as its long-range goal caused rendezvous to fade into the background, since the agency had yet to conceive rendezvous for any purpose other than supporting a space station.40
* This phrase became the standard shorthand for the controversy between direct ascent and rendezvous for the lunar mission in the minutes of the Goett Committee, which was formed in April 1959. The members were Milton B. Ames, Jr. (NASA Office of Aeronautical and Space Research), De E. Beeler (High Speed Flight Station), Alfred J. Eggers, Jr. (Ames), Maxime A. Faget (STG), Laurence K. Loftin (Langley), George M. Low (NASA Office of Space Flight Development), Brice T. Lundin (Lewis), Harris M. Schurmeier (Jet Propulsion Laboratory), and Ralph W. May, Jr. (NASA Office of Advanced Research Programs), secretary. The committee intended both to "take a reasonably long term look at man-in-space problems leading eventually to recommendations as to what future mission steps should be" and to recommend appropriate research programs to support these steps. This function recalled that of the technical advisory committees that had been NACA's instrument for promoting the exchange of information and recommending needed research, although unlike them its membership was drawn entirely from with the organization. NASA research was to be aligned with NASA development, just as NACA research had been aligned with military and industrial development in the past. The Goett Committee was chiefly responsible for choosing lunar landing as NASA's appropriate long-term goal.
Challenge From the Field
Although rendezvous ceased to seem very important to NASA Headquarters, 1960 saw that viewpoint challenged in the field. Several NASA field centers had begun to look more closely at the possibilities, and two, in particular, began to urge strongly an open-minded reassessment of the merits of rendezvous. One was the George C. Marshall Space Flight Center, in Huntsville, Alabama; the other was Langley.
Marshall was unique in NASA for its background and outlook. It was the former Development Operations Division of the Army Ballistic Missile Agency, which joined NASA and received its new name in March 1960.41
Marshall's Director, Wernher von Braun, and his chief lieutenants had been responsible for the German Army's rocket development programs before and during World War II, coming to the United States after the Nazi regime collapsed in 1945.42 They had known the heady atmosphere of Weimar Germany's dreams of space travel,  and they had a long head start on their American colleagues in the hard, practical work of making these dreams real. They had studied space stations long before they joined NASA. Von Braun had moved on to the notion of orbital operations. As early as December 1958, he was urging NASA to base its lunar mission planning on rendezvous techniques. In a presentation to top-level NASA officials, von Braun dismissed direct flight as very difficult, then described four alternative rendezvous schemes, two requiring only Earth orbital operations and two calling for rendezvous in lunar orbit as well.43
Von Braun and his colleagues had been working since 1957 on the concept of using a cluster of relatively small rocket engines to build a booster of 6.7 meganewtons (1.5 million pounds of thrust) as the basis for a space flight program leading to manned lunar landing.44 The booster project was approved by the Advanced Research Projects Agency of the Department of Defense in August 1958.45 Then known as Juno V, the vehicle became Saturn in February 1959 and studies began on suitable upper stages in a complete system for a military lunar mission.46 Whether there was any military need for Saturn was the question of 1959, and the answer was no. The decision to shift Saturn to NASA was behind the transfer of von Braun's group.* 47
Spokesmen for von Braun's group led the defense of the "assembly-in-orbit approach" at Goett Committee meetings during 1959, with strong backing from George M. Low, who urged study of "vehicle staging so that Saturn could be used for manned lunar landing without complete reliance on Nova." The committee supported von Braun's request for a NASA contract to study orbital operations (his group then still belonged to the Army), and Low, who was highly placed in the NASA Headquarters Office of Space Flight Development, helped push it through.48 Von Braun's group studied Saturn's role in lunar landing missions, both manned and unmanned, under NASA auspices during the last half of 1959. The new findings confirmed what an earlier report had concluded, "that a manned circumlunar satellite could be launched from the earth's surface, but some other technique will have to be used for a manned lunar landing with the present state of the art." Most of the chapter on "Manned Circumlunar Flights and Lunar Landings" in the 1959 study report was devoted to the role of orbital operations in these missions.49
Joining NASA did nothing to alter this Center's viewpoint. Until well into 1960, however, Marshall's leanings toward orbital operations produced little work specifically on rendezvous.50  Concerned mainly with development programs, especially Saturn, Marshall had few resources to devote to the kind research needed to locate and solve basic problems of technique. Such studies, in any case, more properly fell to one of NASA's research centers, which could focus on rendezvous itself rather than on the missions that the technique might open up. This was where Langley entered the picture, for whatever these missions might be, in true space flight "there will undoubtedly be space rendezvous requirements."51
Rendezvous research centered on guidance and propulsion at Langley, where two groups were working more or less independently during 1959. In the Aerospace Mechanics Division, John M. Eggleston and his colleagues were looking at the mechanics of orbital rendezvous. And in the Theoretical Mechanics Division, a group headed by John D. Bird was studying launch windows and trajectories for rendezvous.52 The spokesman for Langley in the Goett Committee agreed that lunar landing ought to be "the `ultimate' manned mission for present consideration." But he also voiced Langley's belief that some form of manned space laboratory was "a necessary intermediate step" as a focus for research. That meant a space ferry, and a space ferry meant rendezvous.53 Late in 1959 this concern generated a space station committee at Langley, with a subcommittee on rendezvous headed by John C. Houbolt, then assistant chief of the Dynamic Loads Division. Houbolt was fresh from a successful attack on the problems that had caused several Lockheed Electras to crash. Despite, or perhaps because of, his inexperience in spacecraft technology, Houbolt zealously espoused rendezvous. Although his subcommittee had been formed to look at rendezvous in the context of space stations, Houbolt insisted from the start that it study rendezvous in the broadest terms, since that technique would play a large role in almost any advanced space mission. Loosely organized and largely unscheduled, the subcommittee became a meeting ground for everyone at Langley concerned with any aspect of rendezvous.**54
When Langley hosted the Goett Committee in December 1959, Houbolt was among the space-station committee members invited to describe their work. He concluded by urging a rendezvous-satellite experiment "to define and solve the problems more clearly,"55 the first of many such pleas Houbolt was to make with as little response. Space station thinking still guided rendezvous work at Langley over the next six months.
In May 1960, Langley was once more host to a meeting,  this time of lesser scope but greater impact. Bernard Maggin, from the Office of Aeronautical and Space Research in NASA Headquarters, had called the meeting to discuss space rendezvous and served as its chairman; he was the only member from Headquarters. Maggin had intended to invite to the meeting only the NASA research centers - Langley, Ames, and Lewis - which his office directed. He soon learned, however, that rendezvous had excited wider interest, so he invited the development centers - Marshall and Goddard - as well. The meeting was designed to give the centers a chance to acquaint each other with current research and to exchange thoughts on future prospects.56
Most of the first day was given over to a series of technical papers on propulsion, guidance, and trajectories, which mainly reviewed work in progress.57 They revealed two salient facts about NASA rendezvous research in mid-1960: work centered on rendezvous between space station and ferry, and Langley was doing most of it.
All NASA rendezvous research was in-house; NASA had yet to provide contract funds for industrial or academic studies. This was one of the chief topics at the round-table talks on future rendezvous requirements that took up the second day of the meeting. Lack of funding was ascribed to strong resistance within NASA to any program aimed solely at the modest goal of proving a new technique or advancing the state of the art. To win funds, a research program on rendezvous needed larger ends. Everyone at the meeting believed that NASA ought to begin to develop and prove rendezvous techniques, because all were convinced that the need for rendezvous was going to become urgent within the next few years. What had to be done, then, was to find a context for rendezvous, and the best choice for the task was Marshall, since "resistance to . . . rendezvous [was] currently strong" in both Goddard Space Flight Center and the Space Task Group, NASA's other two development organizations.58
This may have been the most important by-product of the conference - the conclusion that Marshall had both the capacity and the desire to carry through an orbital operations and rendezvous program. In September 1960, Marshall's Future Projects Office was able to tell a gathering of industrial representatives that it had $3.1 million in study contracts to award during fiscal year 1961, a number of them related to rendezvous and orbital operations.59 By the end of the fiscal year, the office had issued $817,422 in contracts to ten corporations and four universities for studies ranging from the broad problems of satellite rendezvous to the design of orbital refueling systems for Saturn.60
Marshall's commitment to the principle of orbital operations began to produce in late 1960 specific studies of rendezvous and orbital mechanics, much as the first proposal of the idea in 1949 had done. As befitted a development center, Marshall's research was mission oriented. Its role in the study of rendezvous hinged on how the technique  might best be used in manned space missions, in particular a manned landing on the Moon.
The focus of work at Langley also shifted, as Houbolt and his coworkers succumbed to the fascination of a novel application of rendezvous technique, rendezvous in lunar orbit. The essence of the idea was to leave that part of the equipment and fuel needed for the return to Earth in lunar orbit while only a small landing craft descended to the lunar surface, later to rejoin the orbiting mother ship before starting the trip home. In one form or another, this idea had appeared in the work of Oberth, Kondratyuk, and the British Interplanetary Society, to say nothing of later writers. But it reached Langley's rendezvous subcommittee via a brief paper by William II. Michael, Jr., little more than a week after the rendezvous conference at Langley had adjourned.
Michael was part of a small group in the Theoretical Mechanics Division that had been working on trajectories for lunar and planetary missions. The group outlined some of its findings in a pamphlet that made the local rounds near the end of May 1960. Michael's contribution was a brief calculation of the amount of weight that might be saved in a lunar landing mission by parking the return propulsion and part of the spacecraft in lunar orbit.61 The idea hit Houbolt like revealed truth:
I can still remember the "back of the envelope" type of calculations I made to check that the scheme resulted in a very substantial savings in earth boost requirements. Almost spontaneously, it became clear that lunar orbit rendezvous offered a chain reaction simplification on all back effects: development, testing, manufacturing, erection, countdown, flight operations, etc. . . . All would be simplified. The thought struck my mind, "This is fantastic. If there is any idea we have to push, it is this one!" I vowed to dedicate myself to the task.62
And dedicate himself he did. Houbolt and a band of disciples embarked on a crusade to convert the rest of NASA to the truth that lunar orbit rendezvous was the quickest and cheapest road to the Moon.
Rendezvous found an important ally in NASA Headquarters late in 1960, when Robert C. Seamans, Jr., arrived in Washington to fill the post of Associate Administrator. Seamans, whose formal appointment dated from 1 September, came to NASA from the Radio Corporation of America, where he had been chief engineer of the Missile Electronics and Controls Division in Burlington, Massachusetts.63 Seamans' division had been one of two Air Force contractors to study requirements for an unmanned satellite interceptor (Saint) during 1959. In 1960, when Saint moved from study to development, RCA got the Air Force contract to develop its final stage and inspection payload and to demonstrate its rendezvous and inspection capability.64
 Saint was part of a quiet but far-reaching Air Force program, much of it concerned with rendezvous and orbital operations, intended to carve out a larger military role in space. Reading the minutes of a November 1960 meeting of the Air Force Scientific Advisory Board, at which both the Air Force and Marshall reviewed rendezvous work and plans, convinced a Space Task Group observer that Air Force planning and progress toward orbital operations "is much further ahead (2 to 3 years) than the NASA Program at MSFC."65
Seamans thus came to NASA with a solid background in rendezvous work. He spent most of his first month as Associate Administrator touring NASA's field centers. At Langley, he talked to Houbolt. Seamans was deeply impressed by Houbolt's account of the weight savings to be achieved even if only the spacecraft heatshield remained in a lunar parking orbit.66 Seamans invited Houbolt to Washington for a more formal hearing before the Headquarters staff. Houbolt and some of his Langley colleagues presented the case for putting rendezvous into the national space program in a mid-December briefing at NASA Headquarters.*** 67
So by the end of 1960 NASA Headquarters had been exposed to the idea of orbital operations, to the potential value of rendezvous techniques in manned space missions other than those related to space stations. It had also been introduced to the case for lunar orbit rendezvous as a basis for manned flight to the Moon. These ideas had worked their way up from the field, chiefly from the von Braun group at Marshall and Houbolt and his colleagues at Langley. The once unchallenged assumption that a lunar mission, if it were to be undertaken, would be launched directly from Earth's surface had now been called into question; and the questions multiplied in the following months.
Mercury as Prologue
Throughout 1959 and 1960, Mercury was the first and only approved American manned space flight program. From the very start, however, few people expected it to be last. The Mercury capsule was essentially experimental, an attempt to master the problems of manned space flight. Someday spacecraft would do more than go up,  circle Earth a few times, and then come down. They would have to be maneuverable, both in space and after they returned to the air. They should be able to fly to a landing, and preferably on land rather than in the water. They should be easy to test and repair, if space flight were ever to be put on something like a routine basis. NASA was ready to suggest research along these lines in its first hastily prepared budget for fiscal year 1960, submitted to Congress early in 1959.
Mercury was an engineering project. Its major goal was "to achieve at the earliest practicable date orbital flight and successful recovery of a manned satellite."68 This dictated utmost reliance on the best-known techniques: a ballistic reentry capsule - blunt, cone-shaped, with almost no aerodynamic lift, recovered by parachute after it returned to the atmosphere.69 But it also excluded some promising alternatives, two of which took tentative shape in NASA's 1960 budget. One was the so-called environmental satellite, a kind of small temporary space station able to sustain one or more men in orbit for several weeks or even months. The other was a maneuverable spacecraft, one equipped with rocket motors to change its path in orbit and endowed with enough aerodynamic lift to alter its flight-path in the atmosphere.
NASA asked for $300,000 to study design changes that might turn Mercury into an orbiting laboratory and for $1 million to study a Mercury refined to make it maneuverable and flyable. Looking toward a real space station, NASA also asked for $3 million to study space rendezvous techniques.70 These modest sums signalled no great commitment. When NASA ran into budget problems, this effort was simply shelved and the money diverted to more pressing needs.71
The view from Space Task Group, the Mercury team, was different. Even during the first hectic months, while Mercury was still moving from the drawing boards into the laboratories, some people in STG were turning their thoughts to what might come next. Although a ballistic capsule might get the job done quickly, it also had patent shortcomings, not the least of which was "that it will be very difficult to control the landing point within a distance of perhaps the order of a hundred miles each way."72 The ballistic capsule had been only one of three basic types under study in 1958 for a manned satellite program. The others were a winged glider and a lifting body, so shaped that even without wings it still had enough lift to allow the pilot some control.73 For later missions, either offered a clear edge over Mercury. The winged glider, which could be flown much like an airplane once it was back in the atmosphere, had been preempted by the Air Force in its Dyna-Soar program.
Dyna-Soar was a development project of the Air Research and Development Command (ARDC). The project received its name in October 1957 and Air Force Headquarters approval in November, some four years after study had begun on vehicles boosted into orbit  by rocket and gliding back to Earth under pilot control. Much of the work had been done under contract by Bell Aircraft Company. NACA joined the project in May 1958 to provide technical advice and help to the Air Force-directed and -funded program, an arrangement reaffirmed by NASA in November 1958. ARDC's consolidated Dyna-Soar development plan in October 1958 aimed the project specifically at developing a winged glider for return from orbit. Later X-20 replaced Dyna-Soar as the project's name.74 Leaving gliders to the Air Force was no hardship since many in NASA, especially in the research centers, preferred the lifting-body approach.75 As early as June 1959, STG could report promising results from studies of building some lift into a Mercury capsule.76
STG was also looking into a more radical approach to controlled spacecraft landing. Between 1945 and 1958, a Langley engineer named Francis M. Rogallo had been working at home on a flexible kite, its lifting surface draped from an inflated fabric frame.  In contrast to other flexible aerial devices like parachutes, a load-bearing Rogallo wing produced more lift than drag, though not as much as a conventional wing. But rigid wings could not be folded neatly away when not in use, and they were inherently far heavier. Rogallo first realized what this might mean in 1952, when he chanced across an article on space travel
with beautiful illustrations depicting rigid-winged gliders mounted on top of huge rockets. I thought that the rigid-winged gliders might better be replaced by vehicles with flexible wings that could be folded into small packages during the launching.77
Rogallo's efforts to promote his insight met scant success until late 1958, when the new American commitment to explore space furnished him a willing audience. In December, the Langley Committee on General Aerodynamics heard him describe his flexible wing and how it might be used in "space ship landing."78 The group responded warmly, and work on the concept moved from Rogallo's home to laboratories at Langley.
A few months later, STG asked Rogallo for an informal meeting to discuss his research. Some of STG's top people, Manager Gilruth among them, showed up on 30 March 1959 to hear what Rogallo had to say.79 Gilruth was impressed enough to suggest at a staff meeting two months later that some study go into a follow-on Mercury using maneuverable capsules for land landing.80
In the meantime, STG was spreading the news about its "preliminary thinking about Project Mercury follow-ups." H. Kurt Strass of STG's Flight Systems Division reported to the Goett Committee on some ideas for a larger, longer-lived Mercury capsule. STG's thinking ranged from an enlarged capsule to carry two men in orbit for three days, through adding a three-meter cylinder behind the capsule to support a two-week mission, to cabling the combined capsule and cylinder to a booster's final stage and rotating them to provide artificial gravity. This was modest compared to the more sophisticated "environmental satellite" favored by Langley, "a true orbiting space laboratory with crew and equipment exchangeable" via ferry.81
The Goett Committee divided on just how large the next step ought to be but agreed that some such step belonged between Mercury and a lunar mission.82 So did the NASA planners, who, during 1959, were drawing up a long-range-plan for manned space flight. Although NASA's future program was "directed heavily toward manned lunar exploration" there was still a place in it for developing maneuverability and a long-life capsule, both based on modifying Mercury.83
In seeking to explore the possibilities of improving Mercury to fit it for more advanced missions, STG was moving beyond the limits of its charter. It had been formed for only one purpose:  to manage Project Mercury. By mid-1959, the initial group of 45 had grown eight-fold, and Gilruth's title had changed from Manager to Director of Project Mercury. Despite this rapid expansion, STG felt understaffed. An STG study in June 1959 concluded that 223 people should be added to the 388 authorized, just "to maintain the schedule set for PROJECT MERCURY." But simply keeping pace was not enough.
In addition, . . . some attention should be given to advanced or follow-on systems to MERCURY. It is estimated that a staff of approximately 20 additional professional personnel should be built up during the next year in order that a year or more gap will not occur in NASA manned space flight operations at the conclusion of the presently planned MERCURY Program.* 84  Gilruth foresaw a total strength of some 900 by 1 July 1960, less than half of them working directly on Project Mercury. The rest would be divided among three other projects - a maneuverable manned satellite, a manned orbiting laboratory, and a manned lunar expedition - and a supporting program in biotechnology and human factors. The maneuverable manned satellite project accounted for 302 of the 485 new positions, showing which goal STG though should he pursued immediately after Mercury.85
During the same month, June 1959, Kurt Strass argued that the time had come to stop just thinking about these projects and to start actually designing one. He proposed forming a group to work out the preliminary design of "a relatively sophisticated space laboratory providing living accommodations for two men for two weeks," ready to fly by late 1962.86 Strass found a sympathetic ear in the chief of the Flight Systems Division (FSD), Maxime A. Faget, who appointed him to head a New Projects Panel within the Division.** It met for the first time on 12 August 1959, and Strass told his fellow Panelists they were there to plan a manned lunar landing through a series of graded steps, the first of which was to define "an intermediate practical goal to focus attention on problems to be solved, and thus serve to guide new technological developments."87
The panel floundered a bit, not quite certain of the direction it should take, but soon zeroed in on the design of an advanced spacecraft suited to the lunar mission, the first step on the road that led to the Apollo spacecraft. That still left a sizable gap in the manned space flight program, which a new engineering report by McDonnell Aircraft Corporation, prime contractor for the Mercury capsule, suggested some ways to fill. The panel decided to take a close look.88
The McDonnell report of September 1959, "Follow On Experiments, Project Mercury Capsules," was the result of a summer's work by a small advanced project group.*** 89 It proposed six experiments that might be conducted with practical modifications of the Mercury capsule, to explore some problems of space flight beyond those to be attacked in Project Mercury.90 The New Projects Panel found none of the McDonnell ideas wholly satisfactory but agreed that parts of the  first three "could be combined into a new proposal which could offer increased performance and an opportunity to evaluate some advanced mission concepts at the earliest opportunity."91
All three experiments dealt with spacecraft maneuverability and guidance. The first sought to achieve some control of landing by adding an external trim-flap device to the capsule, coupled with a simple radar guidance technique or, alternatively, with a more sophisticated inertial guidance system to reduce the capsule's dependence on ground facilities. The second aimed at maneuvering in orbit by adding to the capsule a special adapter to carry a propulsion system, with guidance provided by either a Mercury system or an inertial guidance system. The third experiment was designed to test the inertial guidance system that might be used with either of the first two experiments. The system - inertial platform, computer, and star tracker - would allow the capsule to guide itself toward an orbital rendezvous, to control its touchdown point more precisely, and to navigate on lunar and interplanetary missions. All three experiments used a modified one-man Mercury launched by an Atlas, with minimum changes.92 NASA's planners in 1960 and early 1961 aimed higher than just an improved Mercury spacecraft. In St. Louis, McDonnell proposed a 14-day space laboratory.
The panel saw the prospect of a useful test vehicle in joining an adapter-borne propulsion system to an inertial guidance system. Maneuverable in both space and atmosphere, a capsule so equipped might then be used to develop advanced system components, such as environmental systems for long-term missions, auxiliary power systems, and photographic reconnaissance. These were parts of McDonnell's suggested fourth and fifth experiments. The fourth was a 14-day mission, using an adapter to carry both a propulsion system and the extra supplies and equipment to support the extended time in orbit, with fuel cells substituted for batteries to supply electrical power. The fifth mainly involved adding a camera to the Mercury periscope system to allow the pilot to photograph Earth's surface from orbit.**** The panel asked for "authority to initiate this program to continue with the least possible delay" after the Mercury program.93
The time, however, was not yet ripe. The attractive possibilities of experimenting with a modified Mercury capsule paled in comparison with the far more exciting prospect of designing an advanced spacecraft for a trip to the Moon. When STG's top management met a month later, on 2 November 1959, it was the advanced spacecraft rather than the modified Mercury that they decided to pursue.# 94
 That was the story of STG planning for better than a year. Although engineers were still thinking about an improved Mercury, that thought took second place to work on a new lunar spacecraft.95 Lifting reentry was still seen as an important objective, a point stressed by NASA witnesses in budget hearings early in 1960, but not necessarily as part of the Mercury program.96 By April 1960, the central aim of advanced vehicle development had become "lunar reconnaissance." The possibility of a lifting Mercury received only passing mention, as advanced planning focused on a spacecraft able to orbit the Moon, "a logical intermediate step toward future goals of landing men on the moon and other planets."97 This was the program that officially became "Apollo" in July 1960. As then conceived, it did not go beyond circumlunar flight, although lunar landing was the ultimate goal.98
What was becoming clear was that any advanced Mercury program, such as lifting reentry, was likely to become a major undertaking in its own right.99 In March 1960, STG's summary of projected funding needs for manned space flight programs put the cost of a lifting Mercury project at over $34 million during fiscal years 1960 through 1962.100 STG did go on with its lifting Mercury plans into April 1960, getting as far as a preliminary specification for the reentry control system and plans to solicit contractor proposals for the system.101
Lifting reentry, in principle, had NASA Headquarters approval. Still lacking was a firm commitment based on a specific proposal with clearly defined costs.102 That commitment failed to materialize. In May 1960, Administrator Glennan's budget analysis team turned down STG's request for funds to pursue advanced technical development of Mercury-type capsules. Glennan conceded the probability of Mercury flights beyond the three-orbit mission then authorized, to avoid a break in manned space flights, if nothing else. But thinking about somewhat longer missions was one thing; approving a lifting capsule was something else.103
That decision put a temporary halt to STG efforts to improve Mercury. Mounting problems in the project itself, especially during the last quarter of 1960, kept STG busy, and such advanced work as time allowed was limited to Apollo.
NASA After Two Years
As 1960 drew to a close, NASA's manned space flight program was still limited to Project Mercury, but plans and hopes for a larger enterprise were rife. At the center of NASA's aspirations was a lunar landing program, endorsed by the Goett Committee in mid-1959 and  written into the agency's ten-year plan at the end of the year. This goal was framed on technical grounds, as a legitimate end in its own right and as the best means to focus further work on manned space flight after Mercury. Questions of politics, economics, and the other external forces that would decide whether the United States should actually undertake such a program played no part in the choice of the goal.104 NASA engineers were convinced that they could reach the Moon and that reaching the Moon made sense in technical terms. But the technical facts also forced NASA to settle for planning a lesser program for the 1960s. A landing on the Moon remained the long-range goal, but plans were scaled down for a partway effort, a trip around the Moon and back in Project Apollo.
NASA Ten Year Plan
First launching of a Meteorological Satellite
First launching of a Passive Reflector Communications Satellite
First launching of a Scout vehicle
First launching of a Thor-Delta vehicle First launching of an Atlas-Agena-B vehicle (by the Department of Defense) First suborbital flight of an astronaut
First launching of a lunar impact vehicle
First launching of an Atlas-Centaur vehicle
Attainment of manned space flight, Project Mercury
First launching in the vicinity of Venus and/or Mars
First launching of the two-stage Saturn vehicle
First launching of unmanned vehicle for controlled landing on the Moon
First launching of Orbiting Astronomical and Radio Astronomy Observatory
First bunching of unmanned lunar circumnavigation and return to Earth vehicle
First reconnaissance of Mars and/or Venus by an unmanned vehicle
First launching in a program leading to manned circumlunar flight and to permanent near-Earth space station
Manned flight to the Moon
 The main factor in this less ambitious program was the limited weight-lifting capability of existing boosters, as well as those expected to be ready for the 1960s. The real force of this restriction rested on the widely held assumption that a flight to the Moon would be launched directly from Earth's surface on a very large booster. Outside NASA, workers in the new field of astronautics, picking up a lead from early space-travel writers, had proposed rendezvous as an alternative to direct ascent. Within NASA, this idea was slow to take hold, although a few isolated voices supported it and grew louder. The pressure for change came mainly from the field. NASA's field centers, though under tighter rein than NACA's had been, nevertheless were far from being mere agents of Headquarters. The precise ordering of relationships between Washington and the field has, in fact, been a continuing source of tension and a factor in the frequent reorganizations that NASA has undergone. Policy and long-range planning have tended to center in NASA Headquarters, design and development at lower levels. But what goes on at one level has not always seemed to mesh with what goes on at another. Headquarters policy has sometimes appeared to be nothing more than a belated ratification of work already under way in the field. This is the way rendezvous entered the space program.
Some form of rendezvous in Earth or lunar orbit appeared to offer the prospect of making do with lesser boosters than the giant Nova. While simple in theory, however, orbital rendezvous might well present problems in practice. A program designed to test the technique was beginning to look like a prudent move. This pointed to another aspect of NASA activity during 1959 and 1960, and to a still smaller step between Project Mercury and a lunar landing. Suitably altered, the Mercury capsule might become the basis for a new program. Given a certain eager optimism, such changes might be seen as nothing more than an effort to improve the experimental machine and convert it to an operational model. By 1960, proving rendezvous techniques was beginning to emerge as a logical task for the improved Mercury.
Prospects for a larger program at the end of 1960, whether lunar landing, circumlunar flight, or even rendezvous development, were not, in fact, good. During the last quarter of the year, Project Mercury suffered setbacks that strained STG morale and raised questions about the American manned space flight program.105 The political climate was bleak. President Eisenhower rejected NASA's request for Apollo funds in the coming year's budget and leaned toward the view that Project Mercury was the only manned space flight program the United States needed. NASA's prospects under newly elected President John F. Kennedy seemed not much better.106 Policy, however, was one thing, technology another. NASA could, and did, pursue its technical planning. When the climate changed, NASA was ready.
The Transmutation of Mercury
 During January 1961, NASA's manned space flight program altered course. At the policy-making level in Headquarters, thinking shifted from lunar reconnaissance to lunar landing. This change was crucial, not only for the lunar program itself but also for what was to become Project Gemini; before 1961 was over that shift would provide justification for a rendezvous development program. In the field, the newly independent Space Task Group stopped talking about an improved Mercury capsule and began working on it. Plans for a lunar landing mission and work on an advanced Mercury proceeded through the summer of 1961 at different levels and varying rates. These separate paths converged in the autumn to give birth to a new program.
Whether these efforts would have borne fruit without a sharp change in the political climate is anyone's guess. The past two years had seen their share of false starts, dashed hopes, and aborted plans. But the climate did change. Within months after taking office, President Kennedy and his advisors found compelling reasons to support an American manned space flight program far larger than Project Mercury. One factor was certainly the renewed clamor about a space race between the United States and the Soviet Union. Informed opinion might discount Soviet accomplishments or stress American sophistication against Russian brute force; that smacked of quibbling to the American public, especially after 12 April 1961, when Cosmonaut Yuri A. Gagarin aboard Vostok I became first human being to orbit in space.  Two days later, the chairman of the House Committee on Science and Astronautics was not merely speaking for himself when he asserted, "My objective . . . is to beat the Russians." The President announced his decision on 25 May 1961, in a speech to Congress on "Urgent National Needs." He committed the United States to landing an American on the Moon before the end of the decade.1
NASA had long since begun to lay plans for lunar flights, although throughout 1960 it had tended to focus on flying around, rather than landing on, the Moon. A new direction in NASA thinking surfaced at the quarterly meeting of the Space Exploration Program Council (SEPC) on 5-6 January 1961. The council was a NASA device for smoothing out technical and managerial problems at the highest level. Its members were the heads of the field development centers and Headquarters program offices,* 2 with the Associate Administrator serving as chairman.3 The January meeting was the first presided over by Robert Seamans in his new assignment, and it marked a decisive turning point in the manned space flight program. The first day was devoted to manned lunar landing.
The meeting began with a series of presentations arranged by George Low, Chief of Manned Space Flight in the Office of Space Flight Programs, to provide "a 'first cut' at a NASA Manned Lunar Landing Program."4 Low, an early advocate of orbital staging techniques as an alternative to the Nova direct approach, made sure that the council heard about Earth orbit and lunar orbit rendezvous as well as direct ascent.** 5 The next step was setting up a study team to devise a more complete plan.  This the council did, naming Low its chairman. Unable to agree on the best approach, the council simply asked for "an answer to the question 'What is NASA's Manned Lunar Landing Program?'"6
The Low Committee began its work a week later.*** Low himself drafted its report, revised it on the basis of comments from other members, and submitted it to Seamans early in February.7 The report set out the two themes that came to dominate NASA lunar-mission planning throughout 1961. First, Low argued that both orbital operations and large boosters were going to be needed in the long run. NASA must include Nova-class boosters in the national space program, but "orbital operation techniques must be developed as part of the space program, whether or not the manned lunar landing mission is consider." Second, he insisted that, barring unforeseen problems, rendezvous "could allow us to develop a capability for the manned lunar mission in less time than by any other means."8
In Space Task Group, the question of rendezvous took a different form. It was seen as one of several classes of missions around which a follow-on Mercury program might be built. This was one of the subjects at a meeting on 20 January 1961 between Director Robert Gilruth and his chief lieutenants.**** Max Faget, aided by his Flight Systems Division staff, led the discussion and outlined hardware and booster requirements for several possible types of missions.9 Two broad classes came in for particular attention: one was labeled extended time in orbit, the other was rendezvous.
Extended time in orbit covered two possible missions. The first was an 18-orbit manned Mercury mission based on augmented capsule and environmental control systems. The standard Atlas but Gilruth suggested that the group think about using an Atlas-Agena. Atlas-Agena was a two-stage vehicle. The Atlas, which served as first stage, was a product of the Astronautics Division of General Dynamics Corporation in San Diego, California, and the Agena was built by the Lockheed Missiles & Space Company, Sunnyvale, California. Agena development began in 1957 under the Air Force Ballistic Missile Division.  An improved model, Agena B, with a restartable engine and larger propellant tanks, entered development in June 1959 and flew on 12 November 1960.10 Atlas might or might not have enough power to carry aloft the capsule modified for the mission; but if a primate were to pave the way for a manned mission of 7 to 14 days, then Atlas was clearly lacking. It could not lift the required weight.
Atlas was even more doubtful for rendezvous missions. Faget and his colleagues discussed two types, which differed chiefly in their targets. Both used Mercury capsules modified to make them maneuverable, but the target in the first instance was Saint; in the second, an as-yet-undeveloped space laboratory. Discussion centered on the need for a much "refined capsule with better operational and maintenance capabilities, better door, better wiring, possibly a bi-propellant control system, etc." All this meant weight, more than an Atlas could lift. But the basic objection to the rendezvous mission was that it "might be considered too hazardous for a one-man operation."11
Whatever their merits, all these possibilities were too vague. Before proposing a Mercury follow-on program to NASA Headquarters, STG had to be "more specific with regard to particular flights needed, funding, management, etc." This was the task assigned to Faget,# who had only a week to complete it before a scheduled visit to STG on 26-27 January by Abe Silverstein, head of Space Flight Programs in NASA Headquarters. The meetings with Silverstein resulted in a shift in focus to "the question of capsule redesign to speed up check-out and maintenance."12
With a good deal more work clearly needed, Gilruth turned to James A. Chamberlin. Canadian-born and trained at the University of Toronto and the Imperial College of Science and Technology in London, Chamberlin had been working in aeronautical engineering and design since 1939 for several Canadian firms. By March 1959 he had become chief of design for AVRO Aircraft, Inc., of Toronto, where he worked on the CF-105 Arrow, an advanced interceptor aircraft.13 When that project was canceled, NASA was able to recruit Chamberlin and several of his colleagues.14
Chamberlin joined STG in April 1959; by August he had become acting chief of the Engineering and Contract Administration Division.15 For the next year and half, he directed STG's technical monitoring of Mercury development and production. When, on 1 February 1961, Gilruth assigned him to work on an improved Mercury, Chamberlin remained titular chief of what had since become the Engineering Division  but turned over most of his organization's administrative, technical, and operational matters to his assistants, André J. Meyer, Jr., and William M. Bland, Jr.16 Chamberlin himself went to St. Louis in mid-February; during the next months he actually worked from an office in the McDonnell Aircraft Corporation plant two or three days a week.17
STG's change in status at the beginning of 1961 may have sparked its renewed pursuit of a post-Mercury program. Although located at Langley Research Center in Virginia, STG belonged administratively to Goddard Space Flight Center in Maryland. This clumsy arrangement served no very useful purpose, since the Space Task Group was largely self-directed in any case. So NASA Administrator Keith Glennan announced on 3 January 1961 that STG was henceforth an independent field element, charged not only with managing Mercury but also with planning and carrying out programs "in the general area of manned space flight."18 This was more hope than fact, however; Mercury was still the only approved program, and independence was largely formal. STG stayed at Langley, on which it still depended for much of its support, both technical and administrative.
The union with Langley was the next to go, for a number of compelling reasons: the threatened impact on Langley research of a full-fledged development effort, the strain of fitting a much expanded STG into already cramped Langley quarters, the chance to spread NASA more widely across the country, and the need to move before new programs had progressed to the point where moving would disrupt them.19 These reasons anticipated, rightly as it proved, the President's lunar landing decision. Where to move was settled during the summer of 1961, after a special committee visited 19 possible sites.## 20 Houston won the prize, and the booming space agency joined forces with the booming city.
That massive expansion, which saw the tripling of both the manned space flight program and the center in charge of it, had been well prepared. NASA's first two years had seen most of the relevant issues raised, many of the answers suggested. Nothing had been decided beyond recall, but the channels were carved into which later events flowed. In the first half of 1961, some channels broadened, others dwindled and vanished. Before the summer was over, a far larger, far more complex, and far more costly manned space Right program emerged. An enormous lunar project had joined Mercury and a third project stood in the wings, justified by the needs of Apollo but growing out of the technology of Mercury.
STG Plunges Ahead
 The report of the Low Committee early in February 1961 produced no immediate action. As outgoing Administrator Glennan had warned his colleagues in the January meeting of the Space Exploration Program Council, lunar landing was not something NASA could undertake on its own hook; so large and costly a program needed backing at the highest levels.21 In the uncertain political climate of early 1961, planning for a lunar landing remained temporarily in abeyance, though work on the Apollo spacecraft went ahead in STG. But renewed interest in rendezvous and orbital operations in NASA Headquarters, as shown in the Low report, led to a second inter-center meeting on rendezvous at the end of February. This time the site was Washington, instead of one of the field centers. The agenda reflected the changing nature of rendezvous research within NASA. Though Langley still dominated the discussions on rendezvous studies, Marshall took a full session to describe aspects of the rendezvous and orbital operations program it had under contract. This meeting saw the lunar orbit rendezvous idea introduced to NASA as a whole.22 Until then, it had been limited to Langley circles and NASA Headquarters.
Rendezvous and orbital operations also figured prominently in congressional hearings on NASA's proposed budget for fiscal year 1962 during the first months of 1961.23 The House Committee on Science and Astronautics, in particular, displayed a marked interest in the prospect of orbital rendezvous and scheduled a special hearing on the subject for May.24 NASA's budget included some $2 million for further rendezvous studies. This was much less than NASA had wanted, but the Bureau of the Budget had sliced $6 million from the agency's initial request. The House committee recommended the full $8 million and NASA did eventually get the money.25 In sharp contrast to the marked concern for space station logistics in 1959 hearings, the testimony in 1961 consistently stressed the role of rendezvous in mounting lunar and planetary expeditions and the broad value of rendezvous applications.26
While NASA spokesmen were telling Congress how important rendezvous was going to be, a working group in NASA Headquarters was drawing up guidelines for a full-fledged orbital operations development program. The resulting staff paper, ready in May, presented the case for the immediate "establishment of an integrated research, development and applied orbital operations program." Stressing the need for orbital operations in future space programs, the report urged NASA to set up "an aggressive program," coordinated with other NASA programs and with the Department of Defense, but separate from either. Such a program, the report concluded, would buy for the United States at a cost of roughly $1 billion three important skills:  the ability to intercept and inspect orbiting satellites, to support a space station, and to launch from orbit.
Bernard Maggin, who had arranged the first NASA rendezvous meeting a year earlier, headed the working group.* He sent copies of the report to the program office directors in NASA Headquarters and to the director of Program Planning and Evaluation. His request for comments, however, went unanswered.27 By early May, NASA knew that President Kennedy was ready to approve a lunar landing program. The decision for a speeded up and expanded program transformed the context of NASA planning and made the kind of program Maggin suggested seem far too modest.
In the meantime, James Chamberlin followed his own course. He had arrived in St. Louis in February convinced that his job was to redesign the Mercury capsule from the bottom up. This was a belief not widely shared. The common view had it that Mercury only needed to be improved. Chamberlin felt, and as engineering director of Project Mercury he was surpassingly well qualified to judge, that the Mercury design precluded simple upgrading.28 The Mercury capsule was merely a first try at a manned spacecraft. It clearly took too long to build, test, check out, and launch. The heart of the trouble was Mercury's integrated design, which packed the most equipment into the least space with the smallest weight. This could hardly have been avoided, given the limited weight-lifting capacity of the boosters available for the Mercury program. But integration also meant that reaching parts to test, repair, or replace was harder than it should be.
Chamberlin first met with McDonnell engineers to discuss the improved Mercury on 13 February. Little more than a month later, he had the chance to present some of his ideas to the head of Space Flight Programs, Abe Silverstein. On 17 March, Gilruth and his top-ranking staff journeyed to Wallops Island, Virginia, for a weekend retreat, where they were joined by Silverstein.29 Mercury problems took up some time, but the meeting's main purpose was to discuss advanced programs. This chiefly meant Apollo. Chamberlin did, however, have a chance to describe his approach to redesigning the Mercury capsule.
He had attended the meeting mainly to discuss Mercury's progress. But after Silverstein outlined a series of desirable future Mercury missions, ranging from the one- and three-orbit manned missions already planned to rendezvous development, Chamberlin launched into a largely impromptu blackboard lecture on the program's future, which he saw as very limited. The trouble with trying anything more  ambitious with Mercury than had been planned was that even these relatively modest goals could only be achieved at the expense of the most painstaking and arduous care in testing and checkout. This was not a manned spacecraft problem so much as it was a Mercury design problem. Drawing on his experience with fire control and weapons delivery systems for fighter aircraft, Chamberlin sketched a new capsule structure with its equipment located outside the cockpit in self-contained modules easy to install and check out. Although Chamberlin focused his remarks on capsule modification, he had obviously given some thought to a suitable mission for the new design. He had, in fact, prepared a brochure dealing with an audacious circumlunar flight for the improved Mercury, which Silverstein looked at and dismissed without comment.30
Both Silverstein and Gilruth, however, saw the need for changes along the lines Chamberlin had suggested. Gilruth asked Chamberlin to pursue the ideas in more detail with McDonnell, as the basis for specific proposals. Silverstein authorized STG to prepare a work statement to cover a McDonnell study of modifying the Mercury capsule for enhanced equipment accessibility. STG was also to place an order with McDonnell for parts to be used in several capsules beyond the 20 already contracted for. Looking back, Chamberlin was sure that was where it started: "As far as I was concerned, the meeting at Wallops was the initiation of Gemini."31
On 14 April STG and McDonnell signed an amendment to the original contract for the Mercury capsule. This amendment authorized McDonnell to procure so-called long-lead-time items - those parts that took longest to get - for six extra Mercury capsules. The parts and material so obtained would be used in what was now termed the Mercury Mark II spacecraft, once the design had been agreed upon by NASA and McDonnell. Specifically excluded from this procurement effort were capsule structure, ablation heatshield, and escape-tower systems, but all other capsule systems were covered up to a cost of $2.5 million.32
The design of the Mark II spacecraft was the subject of a second contract. After talks with STG, McDonnell submitted a study proposal on 12 April.33 McDonnell proposed to spend $126,385 for 9,000 hours of engineering study, with two objectives: first, to reduce the time needed to build and check out a Mark II capsule by improving the location of equipment and the way it was installed; second, by means of these changes to make the new capsule easy to modify to meet new program objectives. Capsule shape and heat protection were not to be altered, nor were capsule systems to be replaced or greatly modified. The focus of change was to be rearrangement; moving equipment from inside to outside the cabin and putting it in modular subassemblies, with special concern for escape, retrograde, and recovery systems.34 McDonnell was authorized on 14 April to proceed with the engineering study, and a contract for $98,621 was signed on 24 April.35
By then, the study was already well under way. Chamberlin began calling on others in STG to help him. The first was James T. Rose, a recent transfer to Engineering from Flight Systems Division.36 McDonnell created a small project group for the study, headed by William J. Blatz, with Winston D. Nold as chief assistant project engineer. Although they brought with them several engineers from McDonnell's advanced design section, the new group drew most heavily on Project Mercury, particularly a team led by Fred J. Sanders, for its staff.37 Chamberlin regarded Mercury experience as indispensable. "That was the point," he recalled, "to use and build on experience, to gain and not to start over again . . . without the benefit of the detailed hardware experience."38
The guiding idea shared by Chamberlin and his McDonnell colleagues was "to make a better mechanical design"; capsule parts would be more accessible, leading to "a more reliable, more workable, more practical capsule."39 The experimental Mercury capsule was to be transformed into an operational spacecraft. At this point, neither Chamberlin nor the McDonnell group were much concerned with the purpose such a redesigned capsule might serve. The subject arose, of course, as Chamberlin's lunar scheme shows, but it took a back seat. For the moment, the urgent question was strictly one of improving the engineering design. Working out the objectives for a program based on the improved capsule could wait.
Direct Ascent Versus Rendezvous
While Chamberlin, Blatz, and their co-workers were eyeing the Mercury capsule and seeing, as engineers always can, any number of ways to make it better, events in the upper reaches of NASA were moving during the spring of 1961 toward the conclusion that would eventually give the engineers their chance to put ideas into practice. Enough of a case had been made for rendezvous in the lunar program during the past year to make it seem worth a closer look. But President Kennedy's decision to call for a lunar landing before the end of the decade transformed the context of lunar mission planning.
When NASA planning had first focused on flight around the Moon rather than landing on it, rendezvous lacked any urgency. Orbital operations seemed a matter of expedience, a way of making do with smaller boosters than direct ascent demanded. Circumlunar flight, too, could be launched with smaller boosters, but without any need for rendezvous, and a lunar landing appeared to be a long way off. Nobody denied that larger launch vehicles would be an asset to the American space program,  and nothing suggested that building such vehicles would pose any special problem other than time and money. Rendezvous, on the other hand, was an unknown. How hard it might be, how dangerous, could not be predicted. Nobody denied that rendezvous could be a useful and important technique, but planning the lunar mission around it appeared unnecessarily risky. Under the circumstances, direct ascent could be defended as more prudent.
Kennedy's decision changed all that. Gone were the long stretches of time that had allowed the choice between rendezvous and direct ascent to seem less than urgent. NASA now had to select the method that offered the best prospect for meeting the deadline. Even before it was announced, but knowing that a decision was imminent, NASA began seeking the answer.
On 2 May, Associate Administrator Seamans formed a task group to explore "for NASA in detail a feasible and complete approach to the accomplishment of an early manned lunar mission."40 Most members of the ad hoc group came from NASA Headquarters, as did its chairman, William A. Fleming, then acting as Assistant Administrator for Programs.* 41 Fleming had been working closely with Seamans for several months and had, in fact, drafted the Seamans memorandum that created the task group.
The Fleming Committee had four weeks to size up the scope of the task that NASA faced. This was a tall order for so short a time, and the committee felt compelled to limit itself to one approach.42 It elected direct ascent as "the simplest possible approach - the approach of least assumptions and least unknowns."43 Rendezvous, much the biggest unknown, had no place in the lunar landing program, although it was "an essential program in its own right."44 Having dismissed rendezvous, the Fleming group devoted most of its effort to choosing between solid and liquid propellants for the first stages of Nova-class boosters.45 While this did permit the group to pinpoint some crucial decisions that needed to be made quickly - especially the importance of an early choice of sites for the large ground facilities the lunar mission required46 - it merely avoided the question of rendezvous versus direct ascent. Convinced, as Fleming later remarked, "that it was always possible to 'build something bigger and make it work,'"47 his committee saw no reason to base its study on a risky and untried alternative.
 Others in NASA were not so sure. On 19 May, while the Fleming Committee was still meeting, John Houbolt wrote Seamans from Langley deploring the state of the launch vehicle program and urging more serious attention to rendezvous. He denied any wish to argue for rendezvous against direct ascent but insisted that, "because of the lag in launch vehicle development, it would appear that the only way that will be available to us in the next few years is the rendezvous way. For this very reason I feel it mandatory that rendezvous be as much in future plans as any item, and that it be attacked vigorously."48
This was a viewpoint that Seamans, long a student of orbital rendezvous and openly receptive to such ideas since joining NASA, must have shared. On 25 May, he called on Don R. Ostrander, Director of Launch Vehicle Programs, and Ira H. A. Abbott, Director of Advanced Research Programs, to name "a group of qualified people . . . to assess a wide variety of possible ways for executing a manned lunar landing." Seamans wanted their report quickly, "at about the same time as the one under way by the Ad Hoc Task Group on Manned Lunar Landing." NASA Headquarters furnished none of the six members of this committee, led by Bruce T. Lundin of Lewis Research Center.** 49 Lundin regarded his committee as speaking for the field centers, in contrast to the Headquarters viewpoint expressed by the Fleming group.50 The Lundin report was ready by 10 June, a week before the Fleming report.
Although Lundin's committee discussed other matters, its main concern was to compare the several rendezvous schemes with each other. It pointedly excluded any specific comparison of rendezvous with direct ascent but noted two inherent advantages in rendezvous that promised an earlier manned lunar landing. One was the relative capacity of a rendezvous-based program to absorb increases in a payload weight, which meant that early decisions on booster design and development might not so critically affect the program. The other was the smaller size of launch vehicles required by a rendezvous mission, a size which would not call for the development of large new engines.51
Time limited the Lundin Committee to a brief qualitative survey, which could not compare in scope or detail to the elaborate quantitative assessment provided by the Fleming Committee.*** 52 Clearly, however, the choice between solid or liquid propellants in the first stage or  two of a Nova booster was too restricted; the proper alternative to direct ascent was some form of rendezvous. This proposition won unanimous agreement at a meeting between Seamans and the program directors.**** On 18 June, though only after considerable discussion, they decided to pursue two courses. Ostrander would form a team from NASA Headquarters and Marshall to define an overall plan for using orbital operations to achieve manned lunar landing. At the same time, the Fleming Committee study of direct ascent would be paralleled by an equally intensive investigation of the rendezvous and orbital operations approach.53
The first line of action under Ostrander produced a preliminary project development plan for orbital operations by mid-September.54 For the second, Seamans formed still another ad hoc group that was "to establish program plans and supporting resources necessary to accomplish the manned lunar landing mission by the use of rendezvous techniques" with as much rigor as the Fleming report. He named Donald H. Heaton, his former assistant who had become Assistant Director for Vehicles in Ostrander's office, as chairman of the new group.55
Heaton's group was about the same size as Fleming's, but its members were more evenly divided between Headquarters and the field centers.# Its findings, issued late in August, concluded that "rendezvous offers the earliest possibility for a successful manned lunar landing."56 Despite this parade of studies, as future events were to show, the issue had only been joined, not settled. But the view that rendezvous techniques were important enough to pursue "whether or not rendezvous is selected as an operating mode" for the lunar mission57 was clearly gaining strength. And this viewpoint was crucial to the fate of Mercury Mark II, which had in the meantime taken on a much more sharply defined form.
The Advanced Capsule Design
Chamberlin and Blatz were ready to report progress toward an advanced capsule design early in June 1961. Chamberlin had conceived his task in terms that diverged widely from what was generally expected. Adept at keeping his ideas to himself until they matured,  he was not much of a talker. As far as Space Task Group knew, at least officially, McDonnell was studying an advanced version of the Mercury capsule for just two reasons: to extend the capsule's lifetime in orbit to one day (or 18 orbits) and to make the capsule easier to check out and test before flight.58 The extent of the changes that Chamberlin and Blatz revealed to STG leaders on Friday afternoon, 9 June, took some of them aback.* Chamberlin explained that the primary aim "of the design was to increase component and system accessibility to reduce manufacturing and checkout time." That was no surprise. But to do it, he had packaged and relocated almost every capsule system. Those closest to Project Mercury tended to share Chamberlin's view that the Mercury capsule was inherently limited because of its design - making it better meant making it over. This was, after all, the heart of the case Chamberlin had presented at the Wallops Island meeting in March, and he had followed through along the lines he had then suggested. But others in STG, more distant from the daily problems of working with Mercury, were likely to assume that the capsule needed only relatively minor changes to improve it, not the nearly complete new design that Chamberlin offered.59Chamberlin later justified this approach in an enlightening lecture on the design philosophy of the Gemini spacecraft (which Mercury Mark II was to become).60 The main trouble with the Mercury capsule was that
most system components were in the pilot's cabin; and often, to pack them in this very confined space, they had to be stacked like a layer cake and components of one system had to be scattered about the craft to use all available space. This arrangement generated a maze of interconnecting wires, tubing, and mechanical linkages. To replace one malfunctioning system, other systems had to be disturbed; and then, after the trouble had been corrected, the systems that had been disturbed as well as the malfunctioning system had to be checked out again.61
Mercury designers had been preoccupied with solving such basic problems of manned space flight as reentry heating and human tolerance of both high acceleration and zero gravity, for "the sole purpose of placing a man in orbit in a minimum time." Thus they paid no great attention to making a convenient, serviceable spacecraft. That, however, was precisely what the new design offered. In it,
systems are modularized and all pieces of each system are in compact packages. The packages are so arranged that any system can be  removed without tampering with any other system, and most of the packages ride on the outside walls of the pressurized cabin for easy access. This arrangement allows many technicians to work on different systems simultaneously.62
The Mercury capsule, in contrast, could only be worked on from the inside, which meant, as a rule, only one person working at a time.
The new design attacked a number of other Mercury trouble spots. Perhaps the most troublesome was the sequencing system. Chamberlin argued that one of his chief motives for keeping systems in the new design separated was to avoid the endless complications Mercury experienced because so many sequentially controlled operations were built into it. Most of Mercury's flight operations could be controlled by the pilot, but safety demanded that they also be automatic, each complex series of events triggered by an appropriate signal and ordered through a predetermined sequence by a tangle of electrical circuitry.63 So complex was Mercury sequencing that Chamberlin recalled it as "the root of all evil and anybody that really worked on Mercury - that's all they talked about."64 The new design relied on pilot control, instead of merely allowing it and backing it up with automatic sequencing. The result was a much simpler machine; the 220 relays in Mercury, for example, were reduced to 60 in Mark II.65
What may have been the most complex sequencing of all was demanded by the automatic abort modes in Mercury, which depended on a rocket-propelled escape tower to pull the capsule away from the booster in an emergency during or just after liftoff.66 In Chamberlin's mind, "the sequencing of the escape system was one of the major problem areas in Mercury in all its aspects - its mechanical aspects in the first part of the program, and the electronic aspects later."67 What made this peculiarly frustrating was that the escape tower added hundreds of kilograms to the capsule's weight, even though it was essentially irrelevant to the function of the capsule itself; in a successful flight it was jettisoned shortly after launch. Yet its many relays and complex wiring, besides making it inherently untrustworthy, were major factors in prolonging checkout time. To make matters worse, the Mercury abort modes - NASA shorthand for the methods that allowed the pilot to escape when a booster malfunction threatened his life - were automatic. Some circumstances not actually calling for an aborted mission - including a malfunction of the abort system itself - could trigger one, as happened more than once in the Mercury development program.68
Artist's sketch of ejection seats propelling the astronauts to escape distance from a launch failure. They would be used in emergencies before launch (pad-abort) and in flight to about 18,000 meters altitude.
The new design put the pilot in an ejection seat and eliminated the escape tower.69 This change, if installed, excluded Atlas as a booster for the new capsule. Atlas propelled itself with liquid oxygen and a mixture of hydrocarbons called RP-1, a highly explosive combination if the booster broke up. No ejection seat had the power to kick a pilot  away from an exploding Atlas quickly enough, particularly if escape were not automatically triggered. Safety was thus a key reason for the escape tower and for its automatic features in Mercury. But Chamberlin had just become aware of a new booster that might relax these constraints.
A Drawing of the Titan II, built by the Martin-Marietta Corporation, as proposed to be adapted for manned space flight.
Its name was Titan II, and the Martin Company was developing it as an intercontinental ballistic missile for the Air Force and as a manned booster in the Air Force Dyna-Soar program.70 Albert C. Hall, general manager of Martin's Baltimore Division, had proposed it to Associate Administrator Seamans, an old MIT classmate, for a role in NASA's lunar mission. Although Seamans was skeptical, he arranged for Martin spokesmen to present their case at NASA Headquarters on 8 May 1961. The visit was strictly unofficial, since Titan II was an Air Force project. Any formal contact between NASA and Martin required Air Force sanction. Among those who heard about Titan II that day was Abe Silverstein, who saw enough in the new missile to ask Gilruth to look into the possibility of using it somewhere in the manned space flight program.71 Silverstein dismissed any thought of a role for Titan II in the lunar program.
To Chamberlin, however, Titan II looked very good for the improved Mercury. Weight was the most serious constraint in spacecraft design. An improved Mercury meant a heavier Mercury, since the price for packaged components was extra kilograms. This, in turn, meant that the new design called for a launcher more powerful than Atlas. Titan II had power to spare, its total thrust being almost two and a half times that of Atlas. Not only could it easily lift the heavier spacecraft, but it could also carry the redundant systems that would make it a safer booster for manned space flight. This, in a way, merely augmented what may have been Titan II's outstanding features - simplicity and reliability.72
Titan II ran on storable hypergolic propellants: a blend of hydrazine and unsymmetrical dimethyl hydrazine (UDMH) as fuel with nitrogen tetroxide as oxidizer. Because this combination is hypergolic - fuel and oxidizer burn spontaneously on contact - Titan II needed no ignition system. Since both fuel and oxidizer can be stored and used at normal temperatures - instead of the supercold required by the liquid oxygen of Atlas or Titan I - Titan II required no cold storage and handling facilities. The design and the lessons learned from Titan I combined to reduce the 172 relays, umbilicals, valves, and regulators in the first version of the missile to 27 in Titan II.73 This simplification struck a responsive chord in Chamberlin, who saw in it something to match what he had been trying to achieve in redesigning the Mercury capsule. Booster and spacecraft seemed almost to have been made for each other.74
Titan II's self-igniting propellants had still another advantage.  They reacted much less violently with each other than did the cryogenic propellants of Atlas or Titan I. In June 1961, there was still some question about whether a Titan II explosion would be sufficiently less violent, compared to Atlas, to permit the use of an ejection seat. Chamberlin was not yet ready to spell out his plans for using Titan II, but that was the way he was thinking. And his active distaste for escape towers made him eager to include ejection seats in his design.
Ejection seats not only promised to relieve a major source of trouble by getting rid of the escape tower, but they also furthered the concept of modularization, keeping each spacecraft system, so far as possible, independent. "The paramount objective in the program," according to Chamberlin, "was to dissociate systems." Ejection seats, in what he called "very happy coincidence that was fully realized at the time," also fitted in nicely with another design change, substituting paraglider for parachute recovery.75
STG had not displayed much active interest in Francis Rogallo's flexible wing concept after the initial flurry in early 1959.76 Rogallo and his co-workers at Langley had pushed ahead with their studies in the meantime. By mid-1960, they had convinced themselves that a controllable, flexible wing could carry a returning spacecraft safely to land, thus providing "a lightweight controllable paraglider for manned space vehicles."77 STG rediscovered the paraglider at the start of 1961 as a by-product of work on Apollo. A technical liaison group on Apollo configuration and aerodynamics met at Langley on 12 January.** In the course of describing his center's work for Apollo, the Langley representative mentioned the paraglider landing system: "The feeling at Langley is that if the paraglider shows the same type of reliability in large-scale tests . . . that it has achieved in small-scale tests, the potential advantages of this system outweigh other systems." Engineering design of large paragliders appeared to be no problem and would be demonstrated in manned and unmanned drop tests.78 Space Task Group engineers met informally with Rogallo and his colleagues in February, March, and April to explore the use of a paraglider in the Apollo program.*** The STG team was less than enthusiastic. They believed much work was yet to be done before the device  could be seriously considered as a landing system for Apollo. The biggest unknown was the deployment characteristics of an inflatable wing; no inflatable structure had ever been successfully deployed in flight. Other questions - how the paraglider was to be packaged, whether the pilot's view from the capsule would be good enough for flying and landing with it - were nearly as important and also largely unanswered. The STG team advised gathering at least six months of data before awarding any paraglider development contract.79 At the same time, however, McDonnell engineers were looking at a paraglider for the modified Mercury, and Marshall Space Flight Center had already let two contracts to study paraglider as a booster recovery system. The idea clearly had promise, and in May 1961 Gilruth decided to contract for further study.
Three contractors each got $100,000 for two and a half months to design a paraglider landing system and define potential problem areas.**** The best design was expected later to become the basis for a development contract to "provide the modified [Mercury] spacecraft with the capability of achieving a controlled energy landing through the use of aerodynamic lift."80 In fact, the design studies soon received a new name - Phase I of the Paraglider Development Program.81 Observed by a small technical monitoring group from STG, the paraglider design studies were under way before May ended.# 82 McDonnell engineers also maintained close liaison with paraglider work, independent though it was of the Mercury Mark II study contract.83 The redesigned Mercury, as presented by Chamberlin and Blatz to the Capsule Review Board in June, could he adapted to a paraglider landing system, once it was developed.84
One other significant innovation marked the new design, an enlarged overhead mechanical hatch, which would allow the pilots to get in the spacecraft more easily and to get out more quickly in an emergency. It was another way of making the new spacecraft a truly operational machine, one that could be entered and left like an airplane. Such a hatch was also needed if ejection seats were to be used. But it also had a special virtue that its designers were well aware of, though they did not talk about it. A large mechanical hatch would enable the pilot to leave and return to the spacecraft while it was in orbit and  thus permit what later became known as extravehicular activity, or EVA.85
The many changes proposed by Chamberlin and Blatz did not make the redesigned spacecraft a totally new machine. Though somewhat enlarged, it retained the fully tested and proved shape and heat protection of the Mercury capsule. It was still to be a one-man craft, and its designers expected to use mostly Mercury parts, packaged and rearranged but not otherwise substantially altered. The new design would not be much longer- lived in orbit than Mercury, 18 orbits (or one day) being the most the designers were aiming at.86 Nevertheless, members of the Capsule Review Board seemed staggered by the scope of the changes presented to them. They refused to accept the complete Chamberlin-Blatz package but agreed to reconvene after the weekend to decide if any of the new features might be worth pursuing.87
Chamberlin came back again Monday morning, since he was a regular member of the board, but Blatz had returned to St. Louis.## The board talked over the design of the ejection seat and hatch, simpler sequencing, better accessibility, and an 18-orbit capability. Each of these ideas had its own appeal, but most of them carried a price tag far too high to fit within the scope of the follow-on Mercury program STG was then thinking about, a program budgeted for less than $10 million in the coming fiscal year.88
Although reaching no clear-cut decision, the board still hesitated to endorse Chamberlin's plans in full. Instead, he was allowed to continue working on alternative approaches to an improved Mercury, while McDonnell studied "the minimum modifications that could be made to the present capsule to provide 18-orbit capability" and looked into "a larger retro and posigrade pack."89 This amounted to little more than reviving an early Mercury objective, once the ultimate goal of the program. Growing capsule weight and power requirements, as well as the limitations of the manned space flight tracking network, had forced STG to scrap the 18-orbit mission by October 1959.90 The idea lived on, however, in the form of a proposal to fit the capsule with its own rocket motors to provide the final increment of velocity needed to attain an orbit high enough to resist Earth's gravity for 18 revolutions.91 This was the idea the Capsule Review Board again endorsed at its meeting on 12 June.
Modification or Transmutation
The matter of a post-Mercury manned space flight program was far from settled in the Capsule Review Board meetings of 9 and 12 June.  Chamberlin was not giving up, and McDonnell, despite the board's injunction to limit its work to minor modifications, was still pressing for a more radical effort. At the beginning of July 1961, top STG officials were looking at an ephemeral "Hermes Plan," calling for a new Mark II design much along the lines proposed by Chamberlin and Blatz a few weeks before. This Mark II was contrasted with a minimally redesigned capsule for an 18-orbit mission, now termed Mark I. The question of Mark II design, as Gilruth's special assistant Paul E. Purser noted, was still very much "up in the air."92 Still unclear was the scope of a follow-on Mercury program. A choice in favor of the extensively redesigned Mark II would impose a far greater effort than the slightly altered Mark I.93
A McDonnell group led by Mercury manager Walter F. Burke attended a senior staff meeting at STG on 7 July to outline the company's studies of an advanced Mercury capsule that took three distinct forms. One version, the "minimum change capsule," involved not much more than cutting some hatches in the side of the capsule for better access. Although it could be ready to launch relatively quickly and cheaply (II months, $79.3 million), it had some obvious drawbacks. Better access only accented the capsule's cramped interior, and the hatches themselves weakened the capsule's structure and heat protection. As Chamberlin later remarked, "It was clear that this mod was too little to inspire any additional confidence in the design, and hence make it worth doing. Thus, the merits of the greater modifications became apparent."94 The second McDonnell advanced design, called a "reconfigured Mercury capsule," adhered closely to the Chamberlin Blatz proposal of June. It would take longer to build and cost more than the minimum change capsule (20 months and $91.303 million), but it might very well be worth the expense. And for another two months and $12.248 million, NASA might do even better with McDonnell's third version, a "two-man Mercury capsule."95
The notion of putting more than one man in a modified Mercury capsule was not new, having been suggested at least as early as January 1959.96 That idea had gone nowhere, but Faget revived the possibility at the review board meeting on 9 June 1961. Blatz recalled that, after he and Chamberlin had made their pitch, Faget's comment was, "If we're going to go to all of this trouble to redesign Mercury, why not make it a multiplace spacecraft in the process?"97 Faget's interest in a two-man spacecraft was prompted, in part, by the prospect of extra-vehicular operations. As early as March 1961, he had asked John F. Yardley, McDonnell's manager for Mercury operations at Cape Canaveral, to look into the possibility "of expanding Mercury into a two-man version" for this purpose.98 Others saw reason for a two-man spacecraft in the rigors of long missions. If the Mark II were to be in space for more than a few orbits, then having two men to share the strain  and support each other's activities made good sense.99 There was also a certain compelling logic in building a two-man spacecraft for a program falling between the one-man Mercury and three-man Apollo.100
NASA Headquarters seemed uncertain about the size of the changes STG was thinking about during July 1961. George Low told Associate Administrator Seamans and the Washington program directors on 6 July that McDonnell and STG were working on a minimally modified 18-orbit capsule. He reported that
McDonnell originally looked upon the 18-orbit capsule as a development of a new flight article with substantial increase in size and weight, and incorporating rendezvous capabilities. McDonnell has been advised, however, to proceed on the basis of minimal changes to the existing hardware and to approach design modifications on this basis.101
But a master plan for orbital operations, dated 19 July, included, besides four 18-orbit Mercury flights during 1963, eight one-man Mercury Mark II flights to be launched at two-month intervals - from October 1963 through December 1964 - and to perform rendezvous and docking tests in orbit.102
Sketch of the modularised systems in the two-man spacecraft.
Whatever confusion may have existed, however, was resolved before the end of the month. On 27 July, Abe Silverstein joined Gilruth and other STG leaders, as well as several astronauts, at the McDonnell plant in St. Louis. McDonnell engineers displayed quarter-scale models of four basic spacecraft configurations: an Eighteen Orbit MK I, a Minimum Change MK II, a Reconfigured MK II, and a Two Man MK II. Also on display was a full-size wood and plastic mockup of the cockpit for a two-man spacecraft - Astronaut Walter M. Schirra, Jr., sat in it and exclaimed, "You finally found a place for a left-handed astronaut!"* 103
Although the ideas for an advanced Mercury presented by the McDonnell study team were much the same as they had been 20 days earlier,104 the audience on 27 July now represented NASA Headquarters as well as STG. Silverstein had long been convinced of the importance of Mercury missions more ambitious than merely circling Earth three times. What he saw in St. Louis was apparently enough to tip the scales toward a decision that many in NASA were ready to welcome. On 28 July, during the second day of the St. Louis meeting, Silverstein directed McDonnell to focus all further effort to improve Mercury solely on the two-man approach.** 105 The choice had been made for a larger, rather than a smaller, follow-on Mercury program.  In what was to become a familiar pattern, that program had already grown far beyond its original bounds. The McDonnell study contract, the basis for the company's design work on advanced Mercury, had outlined a relatively modest effort. By the time that contract was signed, on 24 April, the work was well along. In just over three weeks, McDonnell requested and received a contract increase from $98,621 to $187,189.106 McDonnell efforts soon far surpassed that limit. By 6 August, the company had assigned 45 engineers to the study, and the original 9,000 engineering manhours called for in the contract had climbed to almost 23,000; added to that figure were 6,000 shop manhours for building and testing models not even mentioned in the contract. The estimated cost now topped $535,000.107
Since STG had agreed that advanced Mercury needed more study, McDonnell had not felt obliged to wait until its contract had been amended to provide the extra funds. The company spent its own money. This was the kind of initiative that earned the firm a good deal of respect in NASA circles. Where others refused to move without money in hand, McDonnell focused on the task and relied on the good faith of its customer to make up the cost. It was seldom disappointed. In this instance, the company proposed a new contract to cover the extra engineering study and shop work done since 19 June, when contract funds had been exhausted, and to pay its projected expenses through the end of September.108 The original contract and the new request together totaled over $670,000, nearly seven times the figure first approved in April. STG did not issue a new contract but, instead, amended the procurement contract to authorize the additional funds.109
A Technological Imperative
Before the end of July 1961, the joint efforts of Chamberlin, Blatz, and their co-workers in STG and McDonnell had produced the design of an advanced Mercury capsule, Mercury Mark II. Space Flight Programs Director Silverstein had endorsed it. Although the final verdict was not yet in, the larger program seemed to be in the works, something that could scarcely have been predicted when the year opened. The situation was transformed on 25 May, when the President asked the country to assume the burden and the glory of reaching for the Moon.
The metamorphosis of Space Task Group into Manned Spacecraft Center, followed by its move from Virginia to Texas, flowed directly from this decision. STG had been created solely to manage Project Mercury; as a single-purpose task force, it was outmoded. Project Mercury now became only the first step on the path that was to lead Americans to the Moon before 1970.
As always, the lunar mission, in whatever form, held center stage. This was just as true in Headquarters as it was in the field.  Although Washington's chief planning concern was the voyage to the Moon, research and development in the field focused on specific problems raised by a lunar mission and the hardware needed to surmount them. STG, of course, had Project Mercury to worry about; but when it had time to look ahead, what it looked at was the Moon. Even before the President's decision for a lunar landing, STG engineers were hard at work on the spacecraft that would ultimately carry men there.
Once a deadline had been set, the question of rendezvous as part of the lunar mission took on a new guise. By holding out the prospect of using smaller and thus more quickly developed boosters, rendezvous offered a chance to reach the Moon sooner than did a direct approach. During the spring and summer of1961, discussion of this promise became widespread, and support for some form of rendezvous mission gathered strength. Even those who objected to chancing a lunar mission on an unproved technique were quite willing to admit that the technique needed to be developed, if only for its intrinsic value in future manned space flight. The growing conviction of the need for rendezvous, still further bolster by studies during the fall of 1961, provided the framework for what became Project Gemini.
By the time NASA decided that it needed a rendezvous development program, a freshly designed spacecraft was on the drawing boards. Mercury Mark II was not so much the product of planning as it was of a kind of technological imperative, the ceaseless and unquenchable desire of working engineers to perfect their machines. Some features of Mark II did, of course, spring from thinking about the objectives of a program to follow Mercury. But most of the changes in the new design suggested improvement in the abstract, rather than means to defined goals.
When Chamberlin talked about the design, it was in terms of accessibility and convenience, serviceability and simplification, "a better mechanical design" that was "more reliable, more workable, more practical." These are qualities that can never be absolutely realized, though they may be endlessly pursued. During the first half of 1961, Chamberlin, Blatz, and the others pursued them far beyond the intent of those who had set them the task. By July they had reached a point where they were willing to pause, although, as the later career of Gemini was to show, it was not a point at which they could long rest content.
When Silverstein endorsed the two-man Mark II, its designers faced a new task. The gap between a spacecraft design, whatever its merits, and a manned space flight project was a wide one. Early in 1961, NASA Headquarters had set up a formal procedure for planning and carrying out new projects.110 The first step for such large and complex projects at Mercury Mark II now promised to be was a preliminary project development plan. This was the task to which Chamberlin and his colleagues now turned.
From Spacecraft to Project
 When August 1961 began, James Chamberlin, backed by the Space Task Group and McDonnell Aircraft Corporation, had produced the makings of a post-Mercury manned space flight program. The major task, rethinking the design of the Mercury capsule, was finished, although many details had yet to be worked out.1 A Mercury Mark II project had attained a kind of shadow being and had the support of Abe Silverstein, Director of Space Flight Programs in NASA Headquarters. Only NASA's highest echelon remained to be convinced.
So far, the working engineers in STG and McDonnell had been more concerned with an improved spacecraft than with larger goals. To give their ideas substance, they now faced the task of fitting the spacecraft within the framework of a NASA project. This meant finding those larger goals to justify the cost in time and money that turning concept into practice required. It also meant putting together more pieces; a project was more than a spacecraft.
More Than a Spacecraft
Neither Chamberlin and his staff nor the McDonnell designers had specified a booster for their improved versions of the Mercury capsule, although they had mentioned several prospects at one time or another and Chamberlin himself was more than a little taken with the Titan II. During June and July, STG Director Robert Gilruth and his staff had met often, but always informally, with Martin spokesmen,  chiefly James L. Decker, to talk about Titan II as the booster for the scaled-up Mercury.2
The first formal meeting came on 3 August 1961, when Decker briefed Gilruth and his colleagues on "A Program Plan for a Titan Boosted Mercury Vehicle."3 The Martin plan was decidedly optimistic. For just under $48 million, NASA could buy nine boosters, developed, tested, and launched, the first launch to be within 18 months.4 What made this proposal so startling was that Titan II was still mostly promise. Martin's contract with the Air Force to develop the missile was scarcely a year old (June 1960), and Titan II's maiden flight was almost a year in the future. But the company had reason to believe that rapid progress was likely.
For one thing, much of the work and expense of Titan II development would be provided by the Air Force missile program. For another, some of the design and testing of changes needed to convert the missile to a booster for manned space flight had already been done, and more could be expected, as part of the Air Force Dyna-Soar program. The same simplicity and reliability that so appealed to Chamberlin in the Titan II, augmented by the redundant systems its greater power permitted it to carry, likewise promised a quick and successful development program.5
By the end of July 1961, when Silverstein approved the two-man Mark II, STG was all but ready to put that spacecraft on Titan II. Many of the rough spots had already been smoothed away; Martin had been talking not only to STG but to NASA Headquarters and the Air Force. The formal meeting of 3 August simply confirmed a nearly accomplished fact. At a senior staff meeting four days later, Gilruth commented on the vehicle's promise, particularly the greater power that made it "a desirable booster for a two-man spacecraft."6
The choice of a Titan to carry Mercury aloft may have done some violence to classical mythology. The giants of Greek myth were far removed in time and space from the Roman god. Those who first named Atlas and Titan in the mid-1950s were thinking of the symbolism of power, strength, and invincibility, qualities no less appropriate when their missiles were turned to more peaceful uses.7 Yet, in scouring classical mythology to name their missiles, and setting a precedent that NASA followed, they tapped a vein of symbolism far richer than they knew. Just as Atlas, though he bore heaven and Earth on his shoulders, was but a puny shadow of the Titans themselves, so was the Atlas booster far less powerful than the Titan II that succeeded it. Titan II could carry men to new heights, allowing them to say with Isaac Newton, "If I have seen farther, it is by standing on the shoulders of giants."8 Titan might also help to underscore the living relevance of Newtonian science in an age dominated by Einsteinian relativity and quantum mechanics. For if "the 'sputniks' constitute[d] the first  experimental proof of Newtonianism on a cosmic scale,"9 then the spacecraft carried aloft by Titan, shifting its orbital path in response to the commands of its pilots, offered an applied demonstration of Newtonian orbital mechanics. Eventually Titan II would carry the renamed Mercury on its shoulders in flights that soared far beyond the limits previously attained by mankind and would allow them to see farther than they had ever seen before.
At about the same time that Gilruth was endorsing Titan II, Chamberlin was looking at Agena for use as a rendezvous target. On 8 August 1961, he made his first contact with the Lockheed Missiles & Space Company of Sunnyvale, California.10 The Agena was a highly successful second-stage vehicle that Lockheed had developed for the Air Force. In its then-current version, Agena B, it had flown for the first time in 1960. It was powered by a pump-fed rocket engine made by Bell Aerosystems Company of Buffalo, New York. Like Titan II, Agena used storable hypergolic propellants - in this case, unsymmetrical dimethyl hydrazine as fuel, inhibited red fuming nitric acid as oxidizer. The engine had a dual-burn capability; that is, it could be fired, shut off, then fired again.11 This feature, plus its impressive string of successes, gave Agena the look of a winner. It not only seemed reliable, but its extra power offered a chance to practice really large-scale maneuvers once spacecraft and target had docked.12
Chamberlin's talks with Lockheed about Agena as a rendezvous target reflected the new orientation of Mark II work, toward a project rather than a spacecraft. Rendezvous was now a matter of intense concern within NASA. Despite its great promise, as stressed by the several committees that had discussed the subject during the spring and summer of 1961, it was still an unknown. Whether rendezvous would be as simple and useful in practice as it appeared to be in theory was a question that Mercury Mark II might well be able to answer.
Of other questions looking for answers, one of the most pressing involved the effects of extended stays in space on the human body. Mercury might lay some fears to rest, but its short missions could not allay doubts about long-term space dangers. Those doubts would become crucial in the Apollo program. A trip to the Moon and back demanded at least a week, compared to the four and a half hours of the longest Mercury mission then scheduled. Here was another area that Mark II might explore. The large increase in payload weight permitted by Titan II and the greater size of Mark II would allow the spacecraft to carry the extra supplies and batteries or fuel cells to provide electrical power for a mission of one or two weeks.
The end of the first phase of the paraglider development program in mid-August, which proved the feasibility of the concept for recovery of manned spacecraft,13 pointed to still another part Mark II might play. Mercury came back to Earth's surface via parachute.  Uncontrolled return made the ocean the best landing field. But this meant that each landing was a major undertaking in its own right, with fleets of ships and aircraft deployed to ensure the safe recovery of pilot and spacecraft. This clearly would not do if space flight were ever to become a routine enterprise. Fitted out with a paraglider system, Mercury Mark II might show the way to controlled recovery on land.
These were all, however, only ideas that needed to be hammered into specific proposals with goals, costs, and timetables. This was the purpose of the preliminary project development plan that Chamberlin and his co-workers began to prepare early in August 1961. The focus of their effort now shifted from the engineering design of an improved Mercury to framing the program such a capsule might serve. McDonnell reoriented work under its NASA study contract toward "basic and alternate missions for the MK-II Spacecraft" and increased the number of engineers assigned from 45 to 74.14 At the same time, three McDonnell engineers, led by Fred Sanders, journeyed to Langley, where Chamberlin, aided by James Rose and several contracting and scheduling specialists,* was getting started on the preliminary plan for a new project, using the Mercury Mark II two-man spacecraft.15 The first result was ready 14 August 1961.
Reaching for the Moon
The "Preliminary Project Development Plan for an Advanced Manned Space Program Utilizing the Mark II Two Man Spacecraft"16 framed six objectives. They were to be achieved in 10 flights, the first in March 1963 and the rest to follow once every two months until September 1964. The first objective was long-duration flights, with men in orbit for up to 7 days, animals for up to 14. The two extended manned flights, scheduled third and fourth in the program, came first. Two animals flights were then to provide "completely objective physiological data which could not be obtained otherwise." These were to be the sixth and eighth flights, because the planners were not sure that some of the spacecraft components, especially the retrofire system, could be relied upon over so long a time; the required reliability would be shown in the earlier manned flights, when manual backup was available. Otherwise, the only purpose of the manned flights was to  test the ability of the crew to function in space for as long as a week. Russian Cosmonaut Gherman S. Titov completed his 17-circuit, 25-hour mission aboard Vostok II on 6-7 August 1961; although he complained of nausea, he proved that a man could last a day in space.17
A look at the Van Allen radiation belts was the second objective. The first flight was to be an unmanned test to make sure that spacecraft and booster would be compatible for manned missions, but it would also carry biological experiments. Titan II would boost the spacecraft into a highly elliptical orbit, 160 kilometers above Earth at its lowest point but 1,400 kilometers out at its highest and through the Van Allen belts to acquire data on radiation.
Controlled landing was the third goal, to be pursued on all seven manned flights. This meant that the pilot had to have some means of flying the spacecraft toward a relatively limited landing area. The most direct method was to offset the spacecraft's center of gravity to yield some degree of aerodynamic lift, using the attitude control system to roll the spacecraft during its flight through the air and thus control the amount and direction of lift to correct any errors in the predicted landing point. Controlled land landing also demanded some way to cushion touchdown impact. This was a harder problem, but one to which the paraglider seemed to promise an answer.
Rendezvous and docking stood fourth in the list of objectives. The fifth, seventh, ninth, and tenth flights in the program each required two launches, so the Titan II-launched Mark II could meet and dock with the Atlas-launched Agena B in orbit. The planners foresaw the major problem in the first rendezvous missions to be the size of the "launch window," the length of time during which a spacecraft could be launched to rendezvous with its target. The larger the launch window, the greater the difference in speed between spacecraft and target that had to be made good. That was beyond the powers of the spacecraft alone, but the difference might be made up, in part, by the target. Later, with more experience, the engineers expected to reduce the size of the launch window. Then the extra power provided by the target might find other uses, perhaps in "deep space and lunar missions with the target vehicle being used as a booster following rendezvous." The fifth objective was astronaut training, mainly a useful byproduct of the program.18
The plan stressed extensive use of vehicles and equipment on hand, altered as little as possible. The Mark II spacecraft retained what the Mercury capsule had proved, its aerodynamic shape, thermal protection, and systems components. Some changes were demanded by new goals. In the longer flights, crew members needed improved pressure suits, fuel cells to replace batteries, and more stable propellants than hydrogen peroxide in the attitude control system. Although Mercury carried none of the gear required for rendezvous missions,  planners expected to meet these needs with little or no modification of existing inertial platforms, radar, and computers; of the major requirements, only a rendezvous propulsion system was not on hand.
Other major changes were limited to ejection seats instead of Mercury's escape tower and the environmental control system, in essence two Mercury systems hooked together. Since everything else in Mark II differed little if any from the equipment flight-tested in Mercury, the engineers looked forward to only a modest testing effort in the new project. They guessed that it would cost only $177 million to develop, procure, and test eight Mark II spacecraft, two of which were to be reused.19
The Mark II planners were just as sanguine when it came to launch vehicles. Atlas-Agena B could be used almost as it came off the assembly line, at a cost to the program of only $38 million for the four required. Titan II demanded more in the way of changes, but the Air Force would bear most of the cost. The chief exception was lengthened second-stage propellant tanks to increase the payload by 300 kilograms. As a manned booster, Titan II promised to be so simple and reliable that only one extra feature was needed to leave all decisions to abort a mission in the hands of the pilots. That was a redundant guidance and control system. Titan II's most dangerous potential failing, and the only one that demanded an automatic abort system, was first-stage engine hardover. A malfunction in the guidance and control system could drive the gimbaled engines to their extreme positions - hard-over - their thrust vector then being directed at the farthest possible angle from the proper flight path, accelerating the booster away from the correct course in the region where it would be subjected to the greatest dynamic pressure. The danger lay in the possibility of the booster's breaking up before the pilots could react. By adding a second first-stage guidance and control system, the hazards of this failing were all but erased. Since the booster demanded little in the way of new parts, testing could be quite limited. The best estimate of the price of the boosters was $86 million.
The cost of the entire program from drawing board through the last flight came to $347.8 million. It would be managed by a project office that would also take charge of the rest of the Mercury program, the three-orbit flights already planned and the proposed 18-orbit mission using the minimum-change capsule. Forming the core of the new project office would be the 76 members of STG's Engineering Division, at the time chiefly engaged in Project Mercury and largely outside the mainstream of Apollo. The planners were careful to stress that the new office could be fully staffed to a total of 175 and the new program could be carried on without threat to other programs. Mercury would not be hindered, Apollo would not be interrupted.20
Should the proposed project meet with complete success,  the stage would then be set for the sixth objective, which might supplant much of Project Apollo. If the Mark II spacecraft showed itself able to support a crew for seven days or more and if rendezvous proved to be practical, then the advanced program based on the Mark II might "accomplish most of the Apollo mission at an earlier date than with the Apollo program as it is presently conceived." By taking full advantage of the new spacecraft and rendezvous technique, "it is a distinct possibility that lunar orbits may be accomplished by the interim spacecraft after rendezvous with an orbiting Centaur." This prospect was the subject of an appendix to the development plan.
Centaur was a second-stage vehicle then under development that would use high-energy liquid hydrogen as its fuel. If Centaur were inserted into orbit by Titan II, it would have enough power after docking to boost the spacecraft to escape velocity. The deep-space version of Mark II differed from the rendezvous type only in having backup navigation gear and extra heat and radiation protection, 270 kilograms more on a 2,900-kilogram spacecraft. The appendix explored two possible mission sequences. One simply added four flights to the ten in the Mark II program. The first two extra flights were deep-space missions, with Centaur boosting the spacecraft into an elliptical orbit with an apogee of some 80,000 kilometers to study navigation and reentry problems. The last two flights, scheduled for March and May 1965, were circumlunar, and the whole package added only $60 million to the cost of the basic Mark II program.
The alternative was an accelerated program, nine flights in all. The first three flights were the same in both programs - an 18-orbit unmanned qualification and radiation test, an 18-orbit manned qualification test, and a manned long-duration test. In the speeded up program, the fourth and fifth flights developed the techniques of rendezvous and docking with Agena B as the target. Centaur launched by Titan II then replaced the Agena for the rest of the program - two deep-space missions and two flights around the Moon. This faster program put the first Mark II in lunar orbit in May 1964 for a cost not much greater than the basic 10-flight program: $356.3 million versus $347.8 million.21
During the week after its release, the Mark II plan had STG buzzing.22 A second version of the plan came out just a week later, on 21 August. It differed from the first in only one notable respect. All mention of a lunar mission for Mark II had vanished, leaving behind only a circumspect suggestion that, "if a vehicle such as the Centaur were used as the rendezvous target, the spacecraft would then have a large velocity potential for more extensive investigations."23 Even this hint dropped out of later versions of the plan.
The appeal of going to the Moon with Mark II, however, was not so easily quashed.  After cutting circumlunar flight from the Mark II plan, Chamberlin revived the even more daring idea of using the spacecraft in a lunar landing program.24 The booster was Saturn C-3 and the key technique was lunar orbit rendezvous. The scheme involved a lunar landing vehicle that was little more than a 680-kilogram skeleton, to which a propulsion system and propellants were attached. Fully fueled, it weighed either 3,284 kilograms or 4,372 kilograms, depending on choice of propellants. The lighter version used liquid hydrogen, the heavier used hypergolic propellants. Total Earth-launched payload in this mission fell between 11,000 and 13,000 kilograms, one-sixth to one-fifth of the 68,000-kilogram payload then in prospect for the direct ascent lunar mission. The cost was low, $584.3 million plus the expense of two Saturn C-3 boosters, but the risk was high.
The flight plan for this lunar landing program derived from the speeded up circumlunar proposal appended to the Mark II plan of 14 August. The first two flights, in March and May of 1964, were to be unmanned and manned qualification tests of the spacecraft and Titan II. The next two flights put the spacecraft in orbit for extended periods of time. Three flights then developed and demonstrated rendezvous and docking techniques with Agena as target. The eighth and ninth missions had Centaur boosting the spacecraft into an 80,000-kilometer deep-space orbit. Next came three flights to test rendezvous between the manned spacecraft and the unmanned lunar landing craft in Earth orbit, culminating with the crew transferring from one to the other. Flights 13 and 14 had Centaur boosting the spacecraft to escape velocity for an early demonstration of circumlunar capability. Saturn was to launch the 15th flight, a Moon orbital mission. Men would land on the Moon in the final flight, slated for January 1966.25
When Chamberlin proposed this scheme to Gilruth's senior staff at the start of September 1961, he was the first in STG to offer a concrete plan for manned lunar landing that depended on the technique of rendezvous in lunar orbit.26 STG so far had seen little merit in any form of rendezvous for lunar missions, but it reserved its greatest disdain for the lunar orbit version. The Langley partisans of lunar orbit rendezvous had first put their scheme before STG on 10 December 1960, when they rehearsed what they planned to say to Associate Administrator Robert Seamans and his staff a week later.27 On 10 January, John Houbolt and some of his colleagues met with three STG engineers and tried to convince them that lunar orbit rendezvous belonged in the Apollo program. The response was reserved, the scheme dismissed as too optimistic.* 28
 Three months later, Houbolt was back for another briefing, this time supported by a printed circular on "Manned Lunar Landing via Rendezvous." It included one project called MORAD (for Manned Orbital Rendezvous And Docking), a modest two-flight effort to be completed by mid-1963, intended as a quick proof of the feasibility of rendezvous. A small unmanned payload would propel itself to a linkup with a Mercury capsule, its maneuvers under the control of the Mercury Pilot. The key project, however, was MALLIR (Manned Lunar Landing Involving Rendezvous). Chamberlin, who attended this briefing, had known about Langley's rendezvous work, but had not before heard about the lunar orbit version. He asked Houbolt for a copy of the circular and for anything else he had on rendezvous.29
Others in STG had yet to be convinced. Gilruth saw rendezvous as a distant prospect, not something for the near future. Mercury was proving so troublesome that rendezvous, however simple in theory, seemed very far away. He strongly insisted on the need for large boosters:
Rendezvous schemes are and have been of interest to the Space Task Group and are being studied. However, the rendezvous approach itself will, to some extent, degrade mission reliability and flight safety. I am concerned that rendezvous schemes may be used as a crutch to achieve early planned dates for launch vehicle availability, and to avoid the difficulty of developing a reliable NOVA class launch vehicle.30
This viewpoint was widespread in NASA, leading some to resist rendezvous, not because they believed it a poor idea but because it threatened to subvert another goal seen to be more important.
The efforts of Houbolt and his Langley colleagues to sell rendezvous in general, and lunar orbit rendezvous in particular, may have been frustrated less because their concept was faulty than because, as Chamberlin has suggested, "they were considered to be pure theorists with no practical experience." The major trouble with the lunar orbit rendezvous scheme may well have been that it simply looked too good to be true. Paper-and-pencil calculations did yield striking figures, but what looked good in theory might not stand up so well in practice. Chamberlin and his co-workers, although fully alive to the weight-saving features of rendezvous, stressed another aspect - it made a lunar spacecraft easier to design. Direct ascent posed a particularly thorny design problem because the spacecraft had both to land on the Moon and to reenter Earth's atmosphere. A rendezvous mission, however, allowed one design for a lunar lander, a second for a reentry capsule - a distinct spacecraft to meet the special demands of each of these  two most critical phases of the lunar flight. Chamberlin's group had, in fact, centered its work on a lunar-lander design, since reentry problems were already well in hand. Stressed as an answer to design constraints rather than a weight-saving expedient and sponsored by men with plenty of practical experience in Mercury, lunar orbit rendezvous in Chamberlin's plan for a Mark II lunar landing mission received its first serious hearing from STG.31
Toward the end of September 1961, Chamberlin's plan showed up as part of an "Integrated Apollo Program" STG presented to Silverstein and his staff at NASA Headquarters.  What "integrated" meant was adding a Mark II orbital rendezvous project to the Apollo program. Much of the presentation was drawn from the Mark II preliminary plan, but part of it was based on Chamberlin's lunar landing scheme of 30 August. Some of the figures were new: the lunar landing system, complete with propulsion unit and fuel, weighed little more than 1,800 kilograms, roughly half what the first version had. The cost now included the Saturn boosters for a total of $706.4 million, but the flight development plan had not changed.32
Silverstein proved to be no more excited by a Mark II lunar mission in September than he had been by an improved Mercury lunar mission in March. But he was willing to go along with the idea of a rendezvous development project. On 6 October, Silverstein asked for, and got, Associate Administrator Seamans' formal approval for the "preparation of a preliminary development plan for the proposed orbital flight development program." Seamans now granted STG sanction to begin talks with McDonnell on buying the Mark II spacecraft, with the Department of Defense on Titan II boosters and launch-stand alterations, and with the NASA Office of Launch Vehicle Programs on the Atlas-Agena.33
The Mark II project itself, however, had yet to be approved, even though Seamans remarked that "our present plans call for a Mercury Mark for test of orbital operations during 1963 and 1964."34 Still lacking was an approved project development plan. Such a plan, in fact, had yet to be submitted, although copies of Chamberlin's preliminary plan had been making the rounds of NASA Headquarters in search of comments. With his Mark II lunar landing scheme rejected, Chamberlin now set out to revise the Mark II plan and put it in shape for Seamans to sign.
Mercury Mark II Begins
Chamberlin finished the revised project development plan on 27 October 1961.35 The bulk of it followed the August versions word for word, although some new material appeared, some old ideas vanished, and some accents changed. Most striking was the greatly increased stress on the development of rendezvous techniques. Long duration retained first place on the list of objectives, but rendezvous had moved into second, with controlled land landing third, and astronaut training (still incidental) fourth.
Gone were the radiation study and the animal flights; no trace remained of a lunar mission, nor even of a deep-space sortie. The focus became developing the technique, rather than applying it. More of the text dwelt us, with several new paragraphs to describe in detail the special equipment needed for rendezvous navigation, maneuvering, and docking systems. A closing statement of expected  "Project Results," new in the October plan, clearly showed that rendezvous now had priority. The August plan ". . . . for an Advanced Manned Space Program Utilizing the Mark II Two Man Spacecraft" became, in October, a "Project . . . for Rendezvous Development."
The new flight plan also reflected the shift in focus. Although the total number of flights in the program only expanded from 10 to 12, the rendezvous flights doubled - from four to eight. The first flight had become strictly a qualification test of the unmanned spacecraft and booster, the spacecraft to be launched into a 160-kilometer circular orbit. An 18-orbit manned qualification was still second, followed as before by two extended manned missions, though these might now last up to 14 days. All other flights were designed to develop and test rendezvous techniques.
Logically enough, the October plan proposed a starting date of 1 November 1961, instead of 1 September. Two months still separated each flight from the next, the first now scheduled for May 1963, the last for March 1965. Program costs, however, climbed higher than only two more flights might suggest. The new figure was $529.45 million, more than one and a half times the August estimate. Two factors accounted for the seeming discrepancy. One was the new provision for spare spacecraft and boosters: 12 spacecraft rather than 8 (the first plan had called for 2 spacecraft to be re-used in later missions; the revised version planned for 3 spacecraft to be refurbished, but only as spares); 15 Titan IIs instead of 10, the extra 3 to serve as backups; and 11 Atlas-Agenas instead of 4, 8 to fly and 3 spares. The combined effect of these changes added $140.45 million to the programs costs. Most of the remainder of the increase came from a new $29 million item, "Supporting Development," for paraglider.36
STG forwarded the revised project development plan to NASA Headquarters on 30 October 1961.37 Its approval expected as a matter of course, Chamberlin got busy setting up the program. Since McDonnell was obviously going to get the prime contract for the Mark II spacecraft, the company ought to be told to organize itself for the effort to assign key people to the new program, and to make sure that the staff would be available.38 Chamberlin proposed to amend the letter contract between NASA and McDonnell that had authorized the contractor to procure long-lead-time items for Mark II.39 Chamberlin wanted the McDonnell effort tailored to making a general-purpose spacecraft. This meant that Mark II should not only be able to perform its assigned long-duration and rendezvous missions, but also that it ought to be easy to adapt for other missions. Two other design objectives were only slightly less important, both springing from the notion of Mark II as a truly operational spacecraft (in contrast to the chiefly experimental Mercury): it should be simple to test realistically on the ground, leaving actual flights free to focus on major goals  that could only be achieved in space; and it should be easy to checkout, so a faulty spacecraft was less likely to cause a mission failure. To achieve these goals, Chamberlin thought McDonnell had three central tasks to tackle at once: for systems inherited mainly unchanged from Mercury, utmost refinement; for new systems, engineering analysis; and for special problems, like the integration of a paraglider system, special study groups.40
Chamberlin himself formed a Mark II rendezvous group, whose five members were, by mid-October, already talking to people in Langley's Aerospace Mechanics Division about some theoretical aspects of rendezvous.* 41 They had also approached (and been approached by) prospective contractors about what equipment might be needed, which allowed them to rough out a set of guidelines for rendezvous development by 10 November 1961.42 The group then began a series of technical coordination meetings with McDonnell spokesmen in St. Louis, 14-15 November.
McDonnell engineers themselves had been looking at rendezvous for several months, and the meetings showed that company and NASA thinking had diverged sharply. McDonnell had assumed that the target would not be maneuverable and that control of the spacecraft during maneuvers could be either automatic or manual automatic or manual (or some mixture), the choice hinging on how much fuel the spacecraft could carry. The company, in other words, thought the spacecraft it was going to build should be the active agent in rendezvous. In contrast, Chamberlin's group from Manned Spacecraft Center (MSC; Space Task Group had changed its name on 1 November 1961) had approached the rendezvous system as a whole, spacecraft and target, and assumed a highly maneuverable target, with pilot control of the spacecraft and ground control of the Agena.
McDonnell's approach, which favored a combination of automatic and semi-automatic control, required a spacecraft target-tracking radar, and a digital computer and inertial platform for guidance, as well as a high-capacity propulsion system. MSC's preference for semi-manual control for the spacecraft - automatically stabilized but steered by the pilot - combined with target control under ground command stressed changes in the Agena rather than spacecraft equipment: a restartable engine, a data communication system to link the Agena to ground controllers, an optical tracking aid of some kind, a radar transponder, and an attitude stabilization system.
McDonnell and MSC decided to combine their approaches, fitting the spacecraft with the equipment the company believed necessary and  altering the Agena to conform to what MSC wanted. This "would allow the most flexibility in the choice of rendezvous techniques without equipment change."43
By mid-November 1961, McDonnell had completed most of the documents that spelled out the company's view of what should be in the expected contract with NASA to build the two-man spacecraft. The most important was a detail specification of the Mark II spacecraft, issued 15 November.44 The McDonnell design was deliberately conservative, notably in retaining both the launch escape tower and the impact bag used in Mercury.
McDonnell engineers who drew up the specification could not yet be sure that safety permitted striking the escape tower from the design. Still under study was what might happen if a Titan II exploded on the launch pad while the crew was aboard the spacecraft. Whether ejection seats could in fact propel the two men away from an exploding booster fast enough to outdistance the expanding fireball remained in doubt. Speed and range of the ejection seat were both critical. As a hedge, the Mark II design included the escape tower.
The presence of a Mercury-type impact bag in the specification was another cautious note. The Mercury capsule had an inflatable bag that served to cushion the impact of landing. Although the paraglider promised greatly reduced landing stresses, the designers felt that work on the concept was not far enough advanced to allow them to rely on it entirely. No one really believed a either the tower or landing bag was going to be necessary but, faced with drawing up a specification for Mark II, McDonnell engineers chose to put on paper something they knew would work.45
Planning for the second phase of the paraglider program, a two-part system research and development effort, had already begun. In Phase II, Part A, the contractor was to spend eight months in further study of the design concept, chiefly to settle on what configuration would yield the best performance. The second part of Phase II called for the as-yet-unnamed contractor to build a prototype paraglider landing system, to conduct a series of unmanned and manned flight tests, and to complete a final design. The third and final phase of the program would see a paraglider system in production and pilots being trained to fly it.46 On 20 November, North American received official word that it had been awarded the contract and was authorized to begin work.47
The same team that had monitored the paraglider design study for STG** now joined spokesmen for North American, Langley, and Flight Research Center to discuss putting Phase-II A into motion. They soon agreed that the half-scale models and full-size vehicle for  this phase should be based on the Mark II design. "Power requirements, control actuation, landing gear, etc., should be compatible with the MK II spacecraft, where MK II is sufficiently firmed up for this to be practical without delaying the full-scale test program." Most wind tunnel testing would be done by Langley, while Flight Research Center, at Edwards Air Force Base, California, was to take charge of flight testing, all under the aegis of MSC. Even at this early date, the interface - that useful term for the region where two or more things share a common boundary - between paraglider and spacecraft was beginning to pose questions: how the glider and its gear were to be stowed; how it was to be deployed, sequenced, and jettisoned; what kind of cockpit controls and displays it would need; and how it would fit with the emergency escape system.48
When Gilruth and Chamberlin visited NASA Headquarters in late November 1961 to see Associate Administrator Seamans and report on the Mark II program, they had a good deal to talk about. Spacecraft design was just about settled, paraglider development was beginning, and some basic approaches to developing rendezvous techniques had been decided. Although Gilruth's and Chamberlin's meeting with Seamans did nothing to dampen their belief that project approval was only a matter of time, that time was not yet. Seamans was not quite ready to take the final step. November had been a busy month In NASA Headquarters, and the turmoil had touched the Mark II project.
The Last Obstacles
One source of delay was the still unsettled question of the place of rendezvous in NASA planning. The key factor was the size of boosters. The persistent appeal of orbital rendezvous for many NASA and Defense Department planners was its promise (and, in 1961, only its promise) of making do with lesser boosters. Even they were a long way from ready; the most powerful in operation in the United States at that time, the Atlas-Agena, could only put about 1,800 kilograms in Earth orbit. The smallest payload required for a lunar landing mission, even with rendezvous techniques, was thought to be ten times that figure. This was a matter of concern to both NASA and the Department of Defense, leading them to form a joint Large Launch Vehicle Planning Group in July 1961 under Nicholas E. Golovin for NASA and Lawrence L. Kavanau for the Defense Department.* 49
 Golovin, technical assistant to Seamans, spelled out what he believed to be the group's central goal. "The primary basis for organizing information and preparing recommendations for a National Large Launch Vehicle Program will be the assumption that this program will provide vehicle systems for the attainment of a manned lunar landing and return during the fourth quarter of calendar year 1967 or before."50 The group worked from July through October, its efforts yielding a massive preliminary report in November.51
The team, often referred to as the "Golovin Committee," essayed a detailed, quantitative comparison of direct ascent with several forms of rendezvous-based missions, and each of the rendezvous missions with the others. A subcommittee under Harvey Hall, Chief of Advanced Development in NASA's Office of Launch Vehicle Programs, took charge of this phase of the study and asked each of three field centers to prepare a brief for one form of rendezvous mission. Marshall was to work on Earth orbit, Langley on lunar orbit, and the Jet Propulsion Laboratory (JPL) on lunar surface rendezvous. The lunar surface rendezvous scheme grew out of JPL's experience in the unmanned lunar exploration program. It proposed to automatically assemble unmanned modules on the Moon; this assembly would then serve as the return vehicle for a crew carried to the Moon via direct ascent from Earth. Hall's own office furnished data for direct ascent.** 52
By mid-September, preliminary analysis strongly supported some type of rendezvous over direct ascent as the best basis for a lunar mission, though no single rendezvous scheme had a clear edge over the others. The smaller boosters that could be used in such a mission would be ready sooner, which meant more flight tests and greater reliability for less money.53 When Hall reported to the full committee on 10 October, after the field center studies were in,54 lunar surface rendezvous was out of the running and direct ascent nearly so. The choice was narrowing to rendezvous in Earth or lunar orbit, with Hall's subgroup tending to favor some combination of the two.55
This view had the full, even vigorous, support of the committee as a whole.56 In its report, the Large Launch Vehicle Planning Group, after a detailed analysis of the rival schemes, found that orbital rendezvous promised the best chance for an early lunar landing, the lunar orbit version perhaps the quickest.57 Either form of rendezvous in orbit, or some hybrid of the two, would beat a direct ascent mission to the Moon, because the smaller boosters they needed could be ready sooner.58
Despite its elaborate quantitative analysis, the Golovin Committee  did not have the last word in the controversy over direct ascent versus rendezvous for an early manned lunar landing. Too many questions remained open, too many answers were equivocal, pleasing neither NASA nor Defense, and the committee had failed to produce the integrated national launch vehicle program it had been created for.59 So boosters remained the first order of business.
Early in November, Milton W. Rosen, author of NASA's first launch vehicle program in 1959 and Director of Launch Vehicles and Propulsion in NASA's new Office of Manned Space Flight, set up a working group to decide on a large booster program geared to manned space flight.*** 60 Drawing on the findings of the other committees that had been chewing on the problem since May, Rosen's 12-man group was able to submit its recommendations by 20 November.61
The intense two-week study centered on the technical and operational problems posed by rendezvous. The group decided that rendezvous looked good but preferred direct ascent for the lunar mission because rendezvous was still an unknown. That was something the group insisted had to be corrected. Rendezvous had too much promise, both generally for a broad range of future missions and specifically for an early lunar landing, to permit the techniques to go on being ignored. Prudence dictated planning based on direct ascent, but "vigorous high priority rendezvous development effort must be undertaken immediately."62
November 1961 also saw the structure of NASA revamped.63 Almost eight months had gone into a reorganization of the agency to handle a program the size of Apollo. Shortly after he took over the reins as NASA's second administrator, James E. Webb, at a retreat in Luray, Virginia, on 8-10 March 1961, met with his key people from Headquarters and the field centers. Webb stated that the three top leaders of NASA would act as a team in running the agency. He and Dryden would serve as co-equals and Seamans would function as the "operating vice-president," presiding over the daily affairs of NASA. Essentially, Webb said, Dryden would be concerned with "what to do" and Seamans with "how to do it."
After the retreat, the problems of getting Apollo defined, approved, and pieces of its hardware under contract, and to acquire land suitable for the erection of development, test, and operational facilities, gave rise to a surfeit of committees to study and recommend action on one phase of the program or another.  By September, however, Webb knew that NASA could no longer afford to wait on committees to convene and make recommendations. He needed decision makers at the program office levels. Moreover, the field centers seemed to be competing among themselves too much. So Webb, Dryden, and Seamans searched the country for someone who could come into NASA Headquarters and take charge of Apollo and the new Office of Manned Space Flight, an offshoot of the Office of Space Programs now to be a program office in its own right. Radio Corporation of America, which had earlier sent Robert Seamans to become NASA's Associate Administrator, now furnished the Director of Manned Space Flight in the person of D. Brainerd Holmes.64
The old program offices vanished. The four new offices - Space Sciences, Advanced Research and Technology, Manned Space Flight, and Application - were not the semi-autonomous bureaus their predecessors had been nor did they retain control of the field centers. They became less operating line offices, more advising staff offices. The field centers, including the new Manned Spacecraft Center, now reported to the Associate Administrator rather than to Headquarters program officers.
These changes furthered the cause of rendezvous but delayed the Mark II project. Seamans, a longtime supporter of rendezvous, won a stronger hand in NASA programming and a useful ally in Holmes. Silverstein, most powerful of the former program directors and foremost advocate of direct ascent, left Washington. His old office was gone, and, unwilling to accept the leadership of the new Office of Manned Space Flight, he instead assumed directorship of Lewis Research Center.
STG had reported to Silverstein's office. He himself favored the Mark II project, but he also knew that he was going to be leaving Washington after the reorganization. He was understandably reluctant to commit his successor to a large new program. Holmes, who arrived at NASA Headquarters in October, had little to do with the Mark II decision, anyway. The new order left that squarely in Seamans' hands.
Although the reorganization caused some delay, a larger obstacle loomed from another quarter. NASA still depended upon the Air Force for its boosters. In November 1961, smooth progress toward using a modified Titan II in the Mark II project hit an abrupt snag. John H. Rubel, Assistant Secretary of Defense and Deputy Director of Defense Research and Engineering, informed Seamans that the Air Force was now developing a
TITAN III Standard Launch Vehicle System. This vehicle is intended to serve as the single standardized TITAN vehicle to be used in support of both NASA and DOD programs as appropriate. We expect the design to meet any or all need which NASA may have for space application of the TITAN ICBM.
 Rubel asked Seamans to see that all NASA studies of Titan be routed through the Air Force Systems Command, which had just begun a design analysis as the first phase of the Titan III program.65
Titan III differed from Titan II chiefly in adding two very large solid propellant rocket motors. These motors, 3 meters across, were to be strapped to a core, a much strengthened Titan II, to become in effect the booster's first stage. Their firing would carry the booster aloft, where they would be dropped and the liquid propellant engines of what had been the Titan II first stage would ignite. The much more powerful Titan III was to replace Titan II as the booster in the Air Force's Dyna-Soar program. Its use in NASA's Mark II project might further justify its development.66
That the Air Force planned to develop Titan III as a standardized vehicle to meet both its own and NASA's needs for launching payloads  of up to 14 000 kilograms into low-Earth orbit came as no surprise to NASA. Seamans and Rubel had discussed the project, and the Golovin Committee had endorsed it and recommended launching Mark II with the Titan III core. NASA's response, at first favorable, had since cooled. By November 1961, NASA officials evinced little desire to adopt Titan III for any program, least of all Mark II.67 This may have been the real source of friction. NASA had expected to use a modified Titan II in the Mark II project, but Rubel's letter implied that the Titan III core was what NASA would get, like it or not. Not only was the reinforced core likely to be too heavy, but the central logic of the Mark II project demanded that it be done quickly because any delay raised the prospect of conflict with Apollo. Titan III development meant a major new program, which could hardly be completed in time to meet the tight Mark II schedule.68
The Department of Defense countered by claiming that the modifications NASA wanted in Titan II - lengthened tanks and redundant systems - also implied a new development program. This version of Titan II was now unofficially labeled Titan II-½. Efforts to resolve this impasse led to a top-level meeting of NASA and Defense officials on 16 November. They decided to recall the Large Launch Vehicle Planning Group expressly to study the place of Titan III in the long-term national launch vehicle program and to decide whether the Mark II project really needed Titan II-½.69 The order went out two days later, and the planning group reconvened on 20 November.70
When the Golovin Committee had finished its brief but intense study, Seamans and Rubel agreed that the Department of Defense should go ahead with Titan III. Titan II-½ they deemed unnecessary. The Mark II project could be adequately served by "TITAN II missiles, virtually unmodified"; the only changes to be permitted were those that mechanically adapted the booster to the spacecraft and others "specifically aimed at and limited to the marriage of payload and launch vehicle." Major changes in structure or tankage, or "the addition of new or the extensive modification of existing subsystems internal to the missile," were specifically excluded.71 Although NASA failed to get the lengthened tanks and redundant systems it wanted in Titan II, it did get Titan II. Until the day Rubel and Seamans made these recommendations, even that issue was in doubt. But, with the decision of 5 December, the last obstacle to the approval of Mark II vanished. And, as events were soon as show, NASA was not going to have to make do with "TITAN II missiles, virtually unmodified."
Seamans' approval of Mark II took the form of a note at the foot of a three-page memorandum from Holmes' Office of Manned Space Flight on 6 December, which offered a concise statement of Chamberlin's project development plan.  The statement identified the development of rendezvous techniques as "the primary objective of the Mark II project," with long-duration flights, controlled land landing, and astronaut training as "important secondary objectives." It went beyond Chamberlin's plan to point out that rendezvous would permit manned lunar landing to be achieved more quickly and that rendezvous took on special importance when it became part of the lunar landing maneuver itself, an oblique reference to the lunar orbit rendezvous scheme.
Holmes asked for $75.8 million from current fiscal year 1962 funds to start the project at once and promised a formal project development plan in short order. Seamans wrote "Approved" and signed it on 7 December 1961.72 The promised plan appeared the next day. Only the date on the cover and title page distinguished it from the plan of 27 October, copies of which now bore a large red "PRELIMINARY" stamp.73On 3 January 1962, NASA unveiled the first pictures of the new spacecraft and announced that it had been christened Gemini.74
Justification for Gemini
When Chamberlin and his co-workers in STG and McDonnell began to devise a program to fit the new spacecraft they had already designed, the choice of goals open to them was wide. How well and how long man could survive and function beyond the reach of the gravity in which the species had evolved and beyond the shield of air which had sheltered it from the harsh extremes of space had long been matters of concern. Project Mercury could not - and before May 1961 had not even started to - resolve these questions, and answers were essential before men ventured into deep space. The spacecraft's return to Earth was another concern. Landing that could be controlled and directed by the crew to an area more nearly on the order of an airport than the ocean-sized zones required by Mercury was clearly something to be worked for. Neither of these goals, however, was itself enough to justify a program for Mark II. Any post-Mercury program would support longer flights, and controlled landing was more convenience than absolute necessity. Rendezvous, however, presented quite a different picture.
The exciting potential of orbital rendezvous in future manned space flight had largely ceased to be a matter for dispute in NASA after the middle of 1961. Some planners still hesitated to endorse rendezvous techniques as the basis for a lunar landing mission in Apollo, but none denied its long-term importance. Theory and experiment alike suggested that guiding two spacecraft to a meeting in orbit ought to present no special problems, but until the technique could be demonstrated doubts remained. Should rendezvous prove to be as trouble  free in practice as it seemed to be in theory, then it might be worked into planning for the trip to the Moon and allow that journey to be mounted sooner and more cheaply. In late summer 1961, this prospect inspired Chamberlin to propose a program for Mark II that would beat Apollo to the Moon.
Chamberlin first proposed using rendezvous in Earth orbit to allow Mark II to circumnavigate the Moon and followed that up with an even more daring scheme based on rendezvous in lunar orbit to land men on the Moon. This succession reflected the trend of thinking in NASA as a whole. The last half of 1961 saw the technique of lunar orbit rendezvous gain growing support as a means to achieve early manned lunar landing. But Chamberlin was moving far more quickly than his colleagues. Perhaps the greatest defect in his plans was that they assumed the rendezvous technique itself to need no special work, that a few flights would suffice to prove the technique before going on to apply it to larger ends. This was an assumption not widely shared, and both plans were rejected for Mark II, although Chamberlin may well have blazed the trail for rendezvous in Apollo.
This still left the development and demonstration of rendezvous maneuvers as a proper goal for the Mark II project, and that became the basis for Chamberlin's revised plan. This fitted NASA's clearly growing inclination to see a place for rendezvous in its lunar mission. Pressure for a rendezvous development program of some kind was becoming intense. Thinking about lunar orbit rendezvous for Project Apollo could only make the matter seem more urgent. There might be some room for error in Earth orbit, where a failure need not mean the loss of the crew. But that margin did not exist in lunar orbit; sound and fully proved techniques would be crucial.
By late 1961, a rendezvous development program may well have become inevitable, and Mark II was not the only candidate in the field. Phase A of Project Apollo itself and Marshall's orbital operations development program were likely rivals. The Mark II project, however, had a clear edge: a spacecraft already designed and very nearly ready to go into production and a set of sharply defined and suitably limited objectives. When NASA decided late in 1961 that it needed a rendezvous development program, Mark II was there.
Organizing Project Gemini
 When Mark II was approved on 7 December 1961, much of the groundwork had already been laid. Aside from the paraglider, however, whose development was not directly tied to the Mark II project, none of the pieces was yet under contract. The Manned Spacecraft Center itself was not going to build spacecraft, booster, target, or paraglider. In line with the practice pioneered by the Air Force after World War II, NASA relied on private firms to develop and produce most of its hardware. The first priority, even before getting the project office fully in order, was putting the spacecraft under contract and making arrangements with the Air Force for booster and target vehicles.
The Prime Contracts
Because so much of the preliminary design work had been done, MSC had a letter contract for the spacecraft prepared by 15 December.1 Since it called for a "Two-Man Spacecraft" to be developed from "the present Mercury Spacecraft, retaining the general aerodynamic shape and basic system concepts," there was no question of seeking competitive bids. The choice clearly fell to the McDonnell Aircraft Corporation, which had not only developed and was building Mercury but had also been an active partner in drawing up the new design. The company's president, James S. McDonnell, Jr., signed the contract on 22 December.2
 The contract did spell out some major changes demanded by the broad goal of ending up with "a versatile general purpose spacecraft for the accomplishment of space missions of increasing complexity." There were, of course, more specific goals: 14 days in Earth orbit, controlled land landing, rendezvous and docking in orbit, and simplified countdown procedures. All this meant that the new spacecraft had to be larger to carry two men; include ejection seats; have an adapter section that stayed with the spacecraft in orbit to house stores and special equipment; carry systems that would allow it to be maneuvered and docked in orbit and to be controlled in flight and landing; and have its equipment packaged in modules, each independent of the others and located outside the cabin so they would be easy to reach while the spacecraft was being tested and readied for launch.3
Despite these changes, the two-man spacecraft was still viewed as an improved Mercury. The contract required McDonnell to outfit the new spacecraft chiefly with equipment that had already been developed so that in most instances expected changes were small. This permitted a much compressed schedule. McDonnell was to provide full-scale mockups of spacecraft and adapter within six months and of the target vehicle docking adapter (TDA) within ten. The TDA, though McDonnell-built, was to be mounted on the target; it carried the gear needed to connect spacecraft and target in orbit. McDonnell had 15 months to produce the first spacecraft, with others due every 60 days until 12 had been delivered. Because docking came later in the program, the contractor had 23 months for the first TDA.4
The new contract between NASA and McDonnell replaced the earlier contract that had authorized the company to procure long-leadtime items for extra Mercury capsules. Since it was a temporary device to cover expenses during the time it took to negotiate a final contract, the letter contract had a ceiling of $25 million. The final contract was expected by 20 April 1962.5
Although NASA could deal directly with McDonnell for spacecraft development, launch vehicles were another matter. Titan II and Atlas-Agena belonged to the Air Force, and the Air Force was clearly going to have to serve the new project in some role. Just what that role was to be, in fact, may have been the first question tackled after formal approval. On 7 December 1961, the same day that NASA Associate Administrator Robert Seamans approved the project, he and John Rubel, Assistant Secretary of Defense and Deputy Director of Defense Research and Engineering, issued a joint statement on "the division of effort between the NASA and the DOD in the development of space rendezvous and capabilities."
Seamans and Rubel agreed that the program belonged to NASA but that using the Air Force, in essence, as a NASA contractor could help the civilian agency achieve its goals and permit the Air Force  (and other Defense elements) "to acquire useful design, development and operational experience." The Air Force, acting as contractor, would see that NASA got its Titan II launch vehicles and Atlas-Agena target vehicles. (As in the case of the spacecraft, the nature of the project precluded any choice of vehicles to he used.) The Department of Defense also intended to provide launch and recovery support for Mark II missions (the project had not yet been named Gemini) and to help NASA in choosing and training astronauts. Making "detailed arrangements . . . directly between the NASA Office of Manned Space Flight and the Air Force and other DOD organizations" was the next step.6
This task was turned over to an ad hoc group that met for the first time on 13 December. Paul Purser, special assistant to MSC Director Robert Gilruth, headed the MSC contingent, and Colonel Keith G. Lindell led the Air Force team.* Group cooperation was so marked that a first draft of the plan was ready two days later.7 It was passed around in both NASA and the Air Force, and two weeks were enough to put it in final form as the "NASA-DOD Operational and Management Plan" of 29 December 1961.8
The plan assigned launch vehicle development - Titan II and Atlas-Agena - to the Los Angeles-based Space Systems Division (SSD) of the Air Force Systems Command. The set-up was simple for Titan II: SSD would simply act as MSC contractor. Like NASA, SSD itself developed and built nothing. Its role was to manage the "associate industrial contractors" who actually provided the vehicles, with help from the non-profit Aerospace Corporation of El Segundo, California, in general systems engineering and technical direction.9
Arrangements for Atlas-Agena added another organizational layer, however, because NASA was already using the vehicle in its unmanned space flight programs and there was a working Agena Project Office at Marshall Space Flight Center. NASA's newly created Management Council for Manned Space Flight** simply decided to let the Marshall office take care of Atlas-Agena for the manned program as well.  MSC, in other words, had to order the vehicles from Marshall, which, in turn, procured them from SSD.10
MSC set the guidelines for launch vehicle development and had the last word in any technical dispute, but the day-to-day direction of the work belonged to SSD. MSC was to be allowed only limited contact with SSD's contractors, watching but not touching. If MSC saw something that needed to be done, it told SSD, which would pass the word on to the contractor.***
The "Operational and Management Plan" assigned two other major functions to the Department of Defense, with SSD acting as agent. One required SSD to oversee the modification of launch facilities at Cape Canaveral, Florida, to meet the needs of the new program. The other involved SSD in the support of program operations - launching, tracking, recovery - along the same lines already worked out for the Mercury program.11
On 26 January 1962, the plan was endorsed as a working arrangement between NASA's Office of Manned Space Flight and the Air Force Systems Command by the heads of the two agencies, Brainerd Holmes and General Bernard A. Schriever.12 At the next step up the ladder, Seamans and Rubel were not so sure that everything had been taken care of. They had questions about the plan's provisions for Defense operational support and its failure to define in detail a pilot safety program, the astronaut selection and training process, and project scheduling and funding. These matters seemed less pressing, however, than getting on with the development of Titan II and Atlas-Agena. Seamans and Rubel decided to let the plan stand as an interim measure, until a better defined version could be worked out.13 That took another six months and largely confirmed the arrangements already in force.14
Contracting for launch vehicles was in motion even while NASA and Air Force spokesmen were framing the Gemini Operational and Management Plan. NASA Headquarters juggled its fiscal year 1962 research and development funds to come up with $27 million, which it allotted to MSC for Titan II on 26 December 1961. As soon as notice came that funds were on hand, MSC wired SSD that work on the Titan II could start. SSD told the Martin Company's Baltimore Division to go ahead on 27 December.15
In the meantime, the MSC group that was to take charge of Gemini was writing a formal statement of work for Titan II.  Ready on 3 January 1962, it went to SSD with a formal request to buy 15 launch vehicles for Gemini. Although it could hardly have been a surprise, Titan II now appeared to require many more changes than had been allowed in the NASA-Air Force agreement only a month earlier. The terms of the memorandum that Seamans and Rubel had signed on 5 December 1961 explicitly limited changes to the fewest needed to adapt the missile to its spacecraft payload. But that was not going to be enough. To fit Titan II for Gemini would require new or modified systems to ensure the safety of the crew during countdown and launch. This included specifically a system to detect existing or impending malfunctions and signal them to the crew. MSC also expected changes in Titan II to enhance the probability of a successful mission, though what these were to be was not spelled out. The Air Force had Martin Baltimore under letter contract by 19 January 1962.16
Putting Atlas-Agena under contract took longer, despite just as quick a start. The first steps had been taken before the Mark II project was approved. After its mid-November meeting with McDonnell,17 the MSC rendezvous group had been able to define what would be required of Agena in greater detail and to check back with Lockheed Missiles & Space Company, its builder, about how these needs might be met. The MSC group outlined its views on Agena requirements in a note on 19 December 196118 and requested that Lockheed be asked to assess Agena's role in a rendezvous mission. Lockheed responded on 26 January 1962 with a report on Agena systems related to rendezvous - propulsion, communications and control, and guidance - and some informed guesses about further development that might be needed.19
By the end of January, MSC had evolved a fairly clear idea of the rendezvous techniques it planned for Gemini20 and had prepared a statement of work for Atlas-Agena. This was forwarded to Marshall on 31 January, along with a request to buy 11 Atlas-Agenas. Atlas as launch vehicle for Agena was no problem, since it was already being used for just that purpose in other programs. But Agena needed a good many changes to adapt it to its rendezvous role - radar and other tracking aids, a restartable engine, better stabilization, more elaborate controls, and a docking unit were only the more important. Fortunately, time was not so pressing for Atlas-Agena as for the spacecraft and Titan II since it was not scheduled until later in the program. MSC wanted the first target vehicle delivered in 20 months, or about September 1963.21 MSC did not pay its first installment to Marshall for buying Atlas-Agena until early March 1962, and another two weeks elapsed before SSD told Lockheed to go ahead with Gemini-Agena development.22
By March 1962, all major Gemini systems - spacecraft, booster, target, and paraglider - were under contract.  This reflected the care and forethought that had gone into the project plan. It also mirrored the absence of any competition for major Gemini contracts. The project had been designed around an improved Mercury spacecraft, which made the company that built Mercury the only reasonable choice to receive the contract for Gemini. Of boosters powerful enough to lift the new spacecraft, only Titan could be ready in time for Gemini schedules. Atlas-Agena was the only likely target. And paraglider, the only major system to undergo the competition and elimination process and not really tied (on paper) into Gemini, had been under contract before the Mark II project was approved.
Running the New Project
Informal working arrangements and ad hoc groups had carried the Mark II project through its formative stages and handled the first steps in putting it under contract. But something more settled would be needed to oversee the future career of Gemini. By the end of December 1961, a Gemini Project Office was taking shape, though without official status as yet.23 Its first report,* issued on 5 January 1962, was little more than an educated guess at potential problems in meeting Gemini launch schedules. Original launch dates were revised, with the first flight optimistically set for late July or early August 1963 (instead of May). One notable, but unremarked, change spaced the first, second, and third launches only six weeks apart - mid-September for the second, late October or early November for the third - while the remaining flights remained at two-month intervals. Since hard data for real analysis did not yet exist, the report did little more than point up the need for placing subcontracts promptly.24
Setting up the project office was only part of the complicated task of reorganizing the Manned Spacecraft Center and moving it from Virginia to Texas. On 15 January 1962, Director Gilruth announced the formation of separate Mercury, Apollo Spacecraft, and Gemini Project Offices.25 The old Engineering Division was abolished, its staff divided between the new Gemini and Mercury offices. Chamberlin, former head of Engineering and prime mover of the Mark II project, took over as Manager of Project Gemini. Kenneth S. Kleinknecht, Gilruth's technical assistant, became head of the Mercury Project Office (then in the throes of trying to launch John Glenn into orbit aboard Mercury-Atlas 6, an event that took place on 20 February).26 Chamberlin's deputies separated - William Bland remained with the ongoing Mercury program and André Meyer moved into Gemini with Chamberlin.  Meyer recalled that he and Kleinknecht "split the Engineering Division in half. Just about as evenly as we could split it, put half the talent in one group and half the talent in the other group . . . just the two of us sitting across a desk and arguing - 'No, I don't want this man.' 'We want this man.'"
Gemini came out of these sessions with a roster of 44, Mercury with one of 42.** The 18-person staff of MSC's liaison office at the McDonnell plant in St. Louis, headed by Wilbur H. Gray, was assigned to Gemini but served both projects. Meyer took over as chief of project administration in the new office with a staff of 10. The other members of the project office were temporarily grouped in spacecraft management, launch vehicles integration, and flight operations support.27
The first members of what was to become the Gemini Project Office (GPO) arrived in Houston during December 1961; the transfer was largely complete by February 1962. Gemini was among the first MSC elements to be resettled in Houston, once it was fully divorced from Mercury. Meyer's chief task during this period was to recruit, interview, and hire people to fill out the project office, specifically seeking experts with at least ten years' experience in each of the essential disciplines required to manage work on both spacecraft and launch vehicles. This was the central function of the project office: to plan, direct, and coordinate all aspects of the Gemini program and, more specifically, to see that Gemini contractors produced systems that allowed the program to meet its objectives. GPO enjoyed a degree of autonomy that permitted Chamberlin to deal directly with McDonnell and Air Force Space Systems Division. He reported only to MSC Director Gilruth, and that was chiefly a matter of keeping Gilruth informed on the status of the project.28 One of Chamberlin's first concerns was choosing his key staff members. He had Meyer, but for his other two chief lieutenants he turned to the Astronautics Division of General Dynamics Corporation, in San Diego. When interviews with Duncan R. Collins and Willis B. Mitchell, Jr., convinced Chamberlin that these were the men he needed, he got NASA Headquarters to approve his choice, a necessary step because both Mitchell and Collins were appointed at salaries above civil-service levels - so-called excepted positions. Collins became spacecraft systems manager and Mitchell launch vehicle systems manager. Mitchell also took over most of the personnel and functions of "flight operations support" when that branch of the project office quietly disappeared.29
 When GPO officially settled in Houston in March 1962, the Manned Spacecraft Center was an organization without a home. Plans were under way for building a physical plant for the new center at the Clear Lake site south of Houston, but during most of its first two years MSC was housed in rented buildings (eventually a total of 13) scattered over much of the city and at Ellington Air Force Base, about halfway between Houston and Clear Lake. GPO, minus its manager, was installed in offices at the Houston Petroleum Center, a sprawling set of one-story buildings just off the Gulf Freeway. Chamberlin's desk was some distance away on the other side of the Freeway in the Farnsworth & Chambers building, which served as MSC's interim headquarters.30 Such mundane matters as getting from one office to another, phoning a colleague, or even finding a desk complicated life but scarcely slowed the pace of the program.
Coordination meetings between GPO and its prime contractors were already beginning.31 These meetings were Gemini's central management device. Chamberlin and Meyer set up six coordination panels, three for the spacecraft - mechanical systems, electrical systems, and flight operation - and one each for paraglider, Atlas-Agena, and Titan II. The panels provided a setting where design and engineering problems could be talked out and settled as they arose. They also helped to short-circuit such complex chains of command as might have slowed, for example, the target vehicle program, in which GPO had to deal with Marshall, the Air Force, and Lockheed - spokesmen for each sat on the panel and were able to resolve problems with far greater dispatch than might otherwise have been possible. Panel membership was not fixed, but shifted with items on the agenda for each meeting. But the essential experts were permanent, and outside help could be called in as needed.
Decisions reached at each panel meeting, usually once a week, were submitted to Chamberlin. They could be implemented only after he or Meyer had signed the minutes. This had the double advantage of letting those most familiar with the specific problems work out the technical details and, at the same time, keeping the project manager fully informed about what was going on. These coordination meetings remained the heart of the day-to-day decision-making process throughout Gemini's developmental phase. The number of panels grew as problems mounted and new areas needed closer attention. Later in the program, panels concerned mainly with development programs tended to give way to panels oriented more toward operations. At the same time, panels met less often, since there were fewer technical problems to reconcile as development faded into production and operation.32
GPO's function was to manage Project Gemini, not to build spacecraft or boosters.  That was the task of the contractors who, early in 1962, were gearing up for their part.
The Contractors Get Moving
Gemini management at McDonnell comprised six functional divisions corresponding, for the most part, to divisions within the company as a whole, each under a manager who reported to Walter Burke, company vice-president and general manager for spacecraft.* 33 The key position was that of the Gemini Engineering Manager. Robert N. Lindley, like Chamberlin, had found himself without a job when the Arrow project was canceled and had also moved from Canada to the United States. Unlike Chamberlin, however, Lindley found a place in industry.34 As engineering manager for Gemini, his central responsibility was the design and development of the spacecraft. This included not only the work that McDonnell itself was to do but also the specification and technical management of the effort to be farmed out to subcontractors. Under Lindley were three project engineers: Raymond D. Hill, Jr., had charge of electrical and electronic design, Fred Sanders of mechanical design, and William Blatz of design integration and testing.35
The first engineering task was to define the spacecraft as a whole and each major subsystem to conform to the job required by the terms of the NASA contract. Since the basic form and function of the vehicle had already been decided by the time the contract was awarded, the definition phase centered chiefly on refining details and was largely complete by the end of March 1962. The products of this effort were SCDs for each major spacecraft system. The SCD, or Specification Control Drawing, was not the simple document its name implied. Often running to several hundred pages, it set out precisely what McDonnell expected the final system to look like and to do. After each SCD was discussed and cleared with NASA, McDonnell sent it out to potential subcontractors for bids. With minor exceptions, McDonnell developed and built only the spacecraft structural shell and electrical system. All other major spacecraft systems were developed under subcontract, with McDonnell acting as supervisor and integrator.
Like so much else in Gemini, subcontracting plans were well along before the project received formal sanction.  McDonnell had convened a review board early in November 1961, at which procurement and engineering specialists began going over the spacecraft to decide which parts to buy.36 Within a week after James McDonnell signed the contract with NASA, his company was able to present MSC with a list of the major items it planned to procure rather than make and to propose a set of bidders for each item.37
This was the prelude to a January 1962 meeting between Chamberlin, Burke, and Gray to reach an understanding on a standard procedure for securing NASA approval in the company's choice of subcontractors.38 This could become a delicate matter, since a number of Gemini systems were to follow Mercury closely enough to suggest sole-source procurement - that is, asking only one company for a bid instead of seeking competitive proposals from several firms.
McDonnell awarded its first subcontract on a sole-source basis. It was for the development of the spacecraft environmental control system, which supplied the oxygen, regulated the temperature, and disposed of wastes for the crew. In broad terms, it was to be little more than two Mercury systems hooked together, so McDonnell simply selected the company that had developed the Mercury system, AiResearch Manufacturing Company of Los Angeles, California.39 NASA agreed, and McDonnell told AiResearch to go ahead on 19 February 1962.40
McDonnell's second subcontract set the pattern for those systems that had no real Mercury counterpart. The Gemini spacecraft was going to have to maneuver in orbit to achieve rendezvous, and this meant that it had to carry a propulsion system (called OAMS for Orbit Attitude and Maneuvering System). Besides letting a pilot steer the spacecraft, the OAMS also held the ship steady in orbit and, at the start of the mission, provided the power to push the spacecraft away from the spent second stage of the launch vehicle and to insert the craft into orbit - or, in case of trouble, to abort the mission. The complete OAMS had 16 small engines, which burned hypergolic propellants fed under pressure from one fuel (monomethylhydrazine) and one oxidizer (nitrogen tetroxide) tank. All engines were mounted in fixed positions and were run at fixed levels of thrust. Eight of the OAMS engines were rated at 111 newtons (25 pounds of thrust) and fired in pairs, allowing the pilot to pitch, roll, and yaw the spacecraft and so control its attitude. The other eight engines were rated at 444 newtons (100 pounds of thrust); two were oriented to fire forward, two backward, and two to each side. This was the maneuvering part of the system. In July 1962, the rated thrust of the two forward-firing engines was reduced to 378 newtons (85 pounds).
A second spacecraft rocket system, the reentry control system, was functionally distinct from the OAMS but used the same kind of engines,  so the same contractor would develop them. The reentry control system comprised two rings of eight 111-newton (25-pound) thrusters located forward of the crew cabin. Either of the rings alone could handle the job, but the function was crucial enough - holding the spacecraft attitude steady during its reentry into the atmosphere - to justify complete duplication.41
McDonnell decided that any of four companies might supply the OAMS and the reentry control system and asked each of them to submit a technical proposal. The prime contractor rated the bids and sent a survey team of engineering, quality control, and procurement personnel to grade each of the prospective subcontractors on resources and capabilities. North American Aviation's Rocketdyne Division in Canoga Park, California, won the highest combined rating. Although Rocketdyne's quoted cost was highest, it included an extensive test program unusually early in development, a feature that particularly impressed NASA, which made the choice. McDonnell told Rocketdyne to commence work on 26 February 1962.42
By the end of March, most of the major subcontractors had been instructed to proceed, and all had been selected by the end of May. The Air Force Space Systems Division, acting as NASA's contractor for Gemini launch vehicles, moved just as quickly. SSD set up a Gemini Launch Vehicle Directorate to manage booster development, naming Colonel Richard C. Dineen as director and Colonel Ralph C. Hoewing as deputy.** 43 General systems engineering and technical direction of development, with special stress on man-rating - making sure that Titan II was a safe and reliable booster for manned launches - was contracted to the Aerospace Corporation, which filled much the same role in Mercury for the Atlas booster. Aerospace set up its own Gemini launch vehicle program office under James A. Marsh.44
Gemini launch vehicle development was assigned to Martin's Baltimore plant, although the Titan II missile was developed and built in Denver. Baltimore got the nod chiefly to avoid any conflict between booster and missile work, although the decision did also help to sustain a facility that might otherwise have had to shut down.45 Bastian Hello took over as Gemini Program Manager, reporting directly to Albert Hall, Martin vice-president and general manager of one of the three Martin divisions located in Baltimore.
Martin did not set up a Gemini project organization as such. Rather, each of the nine functional departments in Hall's division  appointed a Gemini manager, who took charge of the program work in his area but remained in the normal departmental chain of command.*** Hello also had the help of a program manager at Denver, where the booster's propellant tanks would be built since the tooling required was too costly to duplicate in Baltimore, and a Martin-Canaveral program manager responsible for launch facilities and operations.**** Subcontracts played a much smaller part in the Martin than in the McDonnell scheme of things, largely because the booster differed much less from the missile than the Gemini spacecraft did from the Mercury capsule. For the most part, Martin could simply buy what it needed.46
Those systems that did need to be developed - engines, airborne guidance, ground computers - were not handled by Martin through subcontracts. Instead, they became the subjects of separate SSD direct contracts. The contract for propulsion systems went to Aerojet-General Corporation's Liquid Rocket Operations plant in Sacramento, California, in March. Two other major contracts followed later, one with General Electric in Syracuse, New York, to furnish the booster radio guidance system (the missile used inertial guidance), the other with the Burroughs Corporation of Paoli, Pennsylvania, to supply ground computers and implement launch vehicle guidance equations.47
The target vehicle for Gemini required even less in the way of special arrangements. Both Atlas and Agena were ongoing programs, already well established, and there seemed little need at the outset for anything more than fitting them to Gemini. The Agena Project Office at Marshall, headed by Friedrich Duerr, bought these vehicles for all NASA programs, and Gemini was simply another customer.# For the target as for the booster, SSD acted as NASA's contractor. Atlas-Agena programs were managed by SSD's SLV-3 Directorate, commanded by Colonel F. E. Brandeberry. The Directorate's Program Integration Division, under Major John G. Albert, took care of NASA Agena programs.## 48 SSD authorized Lockheed to proceed with Gemini Agena development on 19 March 1962, and Lockheed assigned Herbert J. Ballard to manage the Gemini program.49
At the time NASA was arranging to buy Agena for Gemini, the model in use was Agena B. Agena B was essentially hand tailored for  each of its missions, but the Air Force had decided to develop a more advanced Agena D, needing only to have the proper equipment modules installed to carry out any particular mission. On 10 May Brockway McMillan, Assistant Secretary of the Air Force for Research and Development, invited NASA to join in this program. This appealed to the engineers, but the managers hesitated for much the same reasons that had obtained in the case of Titan III. Agena D was a distinctly less ambitious effort than Titan III had been, however, and Duerr wired Albert on 11 June that Gemini would use Agena D.50
The Atlas for Gemini was also to be a standardized vehicle, the SLV-3. This improved version of the Atlas included many mechanical and electrical changes designed to make it more reliable, less troublesome. Its total engine thrust was upped by about 10 percent, mainly to offset the weight added by these changes.51 On 23 July Seamans notified Rubel that NASA would support the SLV-3 program and planned to use the standard booster in all NASA activities that required an Atlas. For its projected role in Gemini, Atlas needed nothing that resembled development. The Air Force bought it from the Convair Division of General Dynamics Corporation right off the production line in its San Diego, California, plant.52
The Paraglider Controversy
The one real exception to Gemini's smooth progress through its first half year was paraglider. Its development was a step ahead of the rest of Gemini, North American having been authorized to begin work on 20 November 1961, and the headstart may have accounted for the earlier signs of trouble.
Paraglider was controversial. Although GPO, and Chamberlin in particular, stoutly defended the concept, others in MSC had strong doubts. The Engineering and Development Directorate under Max Faget had been notably cool to the idea from the outset. The key question had been, and still was, "whether the deployment reliability of a single paraglider will equal that of a main and back-up chute system."53 The long-time efforts of Langley's Francis Rogallo, inventor of the paraglider, to sell his concept had been repeatedly countered by the argument that parachutes had proved they could be relied upon to recover spacecraft. Instead of wasting time on an untried concept, Faget's group favored efforts to improve parachute technology to permit land landing. They advocated using a new form of parachute that could be steered, with landing rockets to cushion the final impact as the spacecraft touched down.54
Another source of opposition to paraglider was the Flight Operations Division under Christopher C. Kraft, Jr. Questions of reliability here took second place to concern for the operational problems posed  by paraglider in the Gemini program. For Kraft's division, using paraglider and using ejection seats were two sides of the same coin: one required the other, neither was reliable, and both promised immense practical obstacles to the safe return of the astronauts.55 Kraft himself urged on Chamberlin, and later on MSC Director Gilruth, his objections to both systems.56
Paraglider critics found plenty of ammunition in North American's slow progress toward a working system. At first, paraglider development aim at landing system for manned spacecraft in general. Early in 1962, however, GPO decided that the program ought to be oriented explicitly to Gemini. North American faced a large new effort and a major delay, and not just because the Gemini spacecraft was much larger than the generalized model first planned for. The half-scale free-flight test vehicle would have to be redesigned to carry a flight control system, just as the full-scale model did. North American had to join with McDonnell to design a compatible landing gear system and check it out in a test program. And, finally, North American now had to develop and qualify emergency parachute systems for both half-scale and full-size test vehicles.57
This last demand, in particular, delayed North American, and it was mid-March before a subcontract for the emergency parachute system could be placed.58 Norbert F. Witte, North American's project manager for paraglider, planned to begin free-flight tests of the half-scale model toward the end of May. With its wing inflated and deployed before it left the ground, the test vehicle needed no emergency parachute. It would be towed into the air by a helicopter and released to fly under radio control. This series of tests would allow North American engineers to see how well the paraglider flew, how precise flight control could be, and whether the vehicle could flare - raise its nose to increase wing lift and drag and slow its rate of descent - just before landing.59
These were all questions that needed answers, but the most crucial was still whether or not the wing would deploy in flight. That had to wait for the emergency parachutes, since the test vehicles were too costly to risk without a backup system. Witte expected to have the half-scale emergency system tested by the start of June, when deployment tests could begin. The full-size emergency parachute would take longer but ought to be ready by mid-July. There still seemed to be a reasonable chance to complete this phase of the development program by September 1962.60
Timing was critical for paraglider development, since its place in the Gemini program depended upon its meeting the very tight launch schedule. Despite snags in the current phase of the program, Chamberlin decided that North American needed to get started on the next phase,  a 14-month effort to design, build, and test an advanced two-man paraglider trainer, to start a flight simulation program, and to design and develop a fully man-rated prototype Gemini paraglider landing system.61 That was in March 1962; by May the task was scaled down to require only the design of the prototype system, rather than its complete development. This was expected to reduce the time to five months from the date of the contract award.62
The project office still expected the paraglider to be ready on time, but warned in a 4 May schedule analysis that the program "will require close monitoring to prevent slippage." Paraglider was scheduled to be installed in the second Gemini spacecraft, which would be the first to carry a crew. The first spacecraft, since it was unmanned, was slated to come down by parachute. A prudent response to delays already incurred dictated that plans be laid for using a parachute system in the second spacecraft as well. By mid-June, GPO conceded that the paraglider would not be ready until the third flight.63
A Quick Smooth Start
Despite some doubts about the paraglider, Project Gemini was moving smoothly in the spring of 1962. GPO noted a certain tightness in launch vehicle schedules a might constrict the time needed to resolve any unexpected problems but concluded that close monitoring would help to bring the modified Titan II out on time. Late delivery of some components from McDonnell subcontractors threatened schedules for building the first two spacecraft, but the threat seemed modest. The target vehicle and its booster, Atlas-Agena, appeared to present no problems, even after a slow start, since a target was not needed until the fifth mission.64
Overall, August 1963 still seemed like a reasonable prospect for the first launch. But the ambitious timing of the second launch (the first manned flight in Gemini, earlier scheduled just six weeks after the first),65 was now adjusted to allow a more realistic three months and set for November 1963. The rest of the program held to an every-other-month schedule, the 12th and final flight to be in July 1965.66 From the viewpoint of the project office as it surveyed Gemini progress and prospects in its first half-year, there were no serious problems.67
Project Gemini had won approval in late 1961 over several competing rendezvous development proposals because its design was further along than those of its competitors and because its scope seemed to be limited enough to fit the relatively compressed span of time between the last flights in Mercury and the first mission in Apollo. That these reasons were valid appeared amply borne out by the rapid placement  of contracts during the first months of the project's official existence. Within a matter of six months, most major contracts had been awarded and a firm organizational framework had been established. Even Congress appeared unperturbed that NASA had embarked on a large new project with scarcely any advance warning to those expected to furnish the money for it. In doing so, NASA had not exceeded its authority. Although obliged to lay out its spending plans during budgetary hearings, NASA at that time received a single appropriation for research and development and was largely free to distribute the money as it saw fit. The $75 million in fiscal year 1962 funds needed to get Gemini started were provided simply by shifting money from one account to another inside NASA.68
In hearings early in 1962 on the upcoming fiscal year 1963 budget, NASA spokesmen felt no need to apologize for the new project. Quite the contrary: from Administrator James E. Webb on down, they described it in glowing terms, stressing its role in the development of rendezvous techniques and in extending the length of man's stay in space - but all within the context of a merely enlarged (or advanced) Mercury. This was, of course, a fair picture of the thinking that lay behind Project Gemini, and none of the listening congressmen challenged it.69
Chamberlin summed up the optimism that pervaded Gemini during its first half year in his monthly report on project office activities as of 28 May 1962. He saw no problems that might imply delays for the program, although "all elements of the schedule are extremely tight." There were no technical problems that contractors and project office could not handle. "As technical problems arise they are being assigned to capable organizations for solution with close project office monitoring to assure progress. No technical problems are particularly outstanding at this time."70
Despite its complexity, Project Gemini was meeting only success. The project office remained silent about any doubts it may have had that Gemini's objectives could be achieved on time.
Expansion and Crisis
As summer gave way to fall in 1962, the smooth progress that Project Gemini had enjoyed during its first half year roughened. Concern mounted over the steady expansion and rising costs of the project as a whole. Hopes for using much of Mercury's technology in Gemini eroded. One system after another became the subject of full-scale development, rather than modification or simple transfer from Mercury. The scope of launch vehicle development likewise grew far beyond first expectations. Costs kept climbing until they collided with an unexpectedly restricted budget toward the year's end.
These concerns were virtually unknown outside NASA. But the striking dual mission launched by the Soviet Union in August led some to wonder if the United States had any hope of flying the first rendezvous mission. Vostok III, piloted by Major A. G. Nikolayev, lifted off on 11 August, followed a day later by Lieutenant Colonel P. R. Popovich in Vostok IV. The two spacecraft came close enough to each other to spur some talk of rendezvous. With no means of maneuvering their spacecraft, however, the two cosmonauts could not match orbits or speeds. The Soviet Union had shown only that it could launch two spacecraft in quick succession, so there was still hope for the maneuverable Gemini spacecraft to achieve the first rendezvous, if it survived its troubles.1
Changing Plans and Rising Costs
Preliminary cost estimates from Gemini contractors began reaching the Gemini Project Office in March 1962.  These rough figures pointed toward a large but not yet clearly defined increase in the projected total cost of the program. Air Force Space Systems Division (SSD) discussed finances with the project office at the first launch vehicle coordination meeting on 1 March and furnished its first budget estimate for the program at a meeting in Houston later that month. Boosters now appeared likely to cost Project Gemini a good deal more than had been supposed. The development plan of December 1961 had assumed $113 million for modified Titan II launch vehicles. But the March 1962 figure was half again as much - something over $164 million.2
The statement of work for Titan II that SSD had received early in January called for more than the limited modifications first proposed. It required a malfunction detection system and other unspecified changes to improve the missile. Making sure that Titan II could safely launch manned spacecraft - referred to as manrating - was crucial, and it was going to cost money. A revised statement of work in mid-May 1962 spoke of "an adaptation of the Titan II ICBM," rather than "a development of the present Titan II ICBM," and spelled out the changes required in greater detail. They included not only a fully redundant malfunction detection system but also a backup flight control system; an electrical system with backup circuits for guidance, engine shutdown, and staging; inertial instead of radio guidance; and a new launch tracking system.3
The target vehicle likewise soon seemed to demand more than had first been expected. Even though Agena work was moving at a slower pace, by May the $88 million programmed for Atlas-Agena development in the December 1961 plan had climbed above $106 million.4
The project development plan had the Gemini spacecraft costing $240.5 million. This figure, like those for launch and target vehicles, could not have been more than an educated guess, with a natural bias toward guessing on the low side to make the program more palatable. But McDonnell's first formal cost proposal for the Gemini spacecraft still came as something of a shock. The first step in negotiations between the project office and McDonnell to convert the letter contract of December 1961 into a definitive contract was a series of technical meetings in Houston between 19 April and 24 May 1962, to make sure that both sides agreed on plans and specifications.5 McDonnell's "Gemini Spacecraft Cost and Delivery Proposal," prepared for these meetings, raised the spacecraft ante to $391.6 million.6
This new and higher estimate was based in part on McDonnell's more careful study of the cost of what the contract called for, in part on its enlarged view of what the program ought to include. The letter contract, for example, had mentioned the need for flight simulators and trainers as well as test spacecraft but included no specifics.  A new feature of engineering development for Gemini was to be the use of a number of test articles - spacecraft built for early static and dynamic testing - for want of which Mercury had sometimes been delayed. GPO admitted that building them might slow spacecraft construction at first but believed that the data they provided would more than make up for the temporary setback.7 McDonnell proposed four boilerplate spacecraft (metal models designed to be used chiefly in escape and recovery system testing) and four static articles (non-flying spacecraft to be used in structural tests). McDonnell also proposed to add to Gemini a test program that it had worked out in Mercury. Known as "Project Orbit," this entailed building an extra spacecraft and target docking adapter for an extended series of laboratory-simulated orbital missions "to investigate potential problems and to evaluate engineering changes generated during the life of the program."8
A major part of crew training for Gemini depended on simulating in great detail every aspect of a mission, to expose the astronauts before they left the ground to anything they might meet during a flight. The basic device was a flight trainer, a precise duplicate of the real spacecraft, in which crews could fly a complete simulated mission from launch through touchdown, seeing through its windows what they would see in flight, hearing the noises - even feeling the vibrations - they could expect. There were to be two flight trainers, one in Houston and the other at Cape Canaveral, each hooked up to mission control and remote displays to form a complete mission simulator.
Three aspects of a mission were outside the scope of the flight trainers. One involved the forces imposed upon the astronauts by high acceleration during launch and by rapid deceleration during reentry. These stresses could be matched on a man-carrying centrifuge. The project office planned to use the one at the Naval Air Development Center in Johnsville, Pennsylvania, its gondola fitted out with a mockup of the inside of the spacecraft. Maneuvering in orbit to rendezvous was the second aspect. This was to be simulated by a translation and docking trainer, in which the crews would practice techniques of rendezvous and docking.9 The third, extended weightlessness, was then beyond human ingenuity to imitate.
Training equipment and test articles together, increased in detail and enlarged in scope, came to just under $39 million in McDonnell's cost proposal. McDonnell also needed money to cover its roles in mission planning and launch operations support and for spare parts and checkout gear, to name only some of the more costly items. And all this aside from the expense of developing and building the spacecraft ($242.7 million), which alone exceeded the December budget ($240.5 million).10 Even at that, McDonnell's estimate was still little more than guesswork. Few of the company's subcontractors had yet provided any hard financial data. The chiefs of procurement and financial management  at MSC jointly deplored both the size of the McDonnell estimate and the lack of data on which it was based, a viewpoint that echoed Paul Purser's marginal note on SSD's interim financial plan for boosters in April 1962: "This is still up in the air. Attempts are being made to bring down these costs." 11
On 12 May 1962, in a review of Project Gemini for NASA Administrator James Webb, the Office of Manned Space Flight revealed for the first time the pattern of rising costs that was beginning to mark the program. Since the project development plan was issued, little more than five months earlier, Gemini's expected cost had climbed from $529.5 million to $744.3 million.12 Given the shaky data on which the new total depended, it could not be the last word. The program kept growing and technical problems began to appear, not all of them in areas where they had been expected.
Some Foreseeable Problems and a Surprise
As Project Gemini moved from design into testing during the spring and summer of 1962, problems multiplied, although not (with one exception) beyond what might be seen as the normal headaches of a large-scale research and development project. Those areas that demanded the longest step beyond current practice were those where trouble threatened. The paraglider program, with its early start, began running into marked delays in planning and design before the rest of Project Gemini. When actual testing began in May 1962, only two contract months remained to settle on the best design for a paraglider landing system.
The first task was qualifying an emergency parachute recovery system for the half-scale vehicle. North American began on 24 May with a successful drop test at the Naval Parachute Facility in El Centro, California, near the Mexican border. Two failures followed before a second success, on 20 June. What should have been the final drop to complete qualification failed on 26 June, when the vehicle's electrical system shortcircuited. North American shuttled the vehicle 260 kilometers back to its plant in Downey for a closer look, which revealed a design flaw. The company reworked the test vehicle and returned it to El Centro for another try, on 10 July, with no better luck. This time the drogue designed to pull out the main parachute failed to do so. After another round trip to Downey for changes, everything worked on 4 September. GPO agreed with North American that the half-scale emergency landing system was now qualified. But two and a half months had been lost.
The full-scale emergency system proved even harder to qualify. First came design problems, then the parachutes were late in arriving.  North American could not ship the test capsule to El Centro until 20 July. The Air Force's 6511th Test Group, which ran the El Centro test range, demanded a special test to be certain the vehicle's pyrotechnic devices were safe - that delayed the first qualification flight until 2 August. It was a success, but more delays followed - first bad weather, then the lack of a launch aircraft. The second drop, on 21 August, was marred by one of the three main parachutes breaking loose. Damage was only minor, as it was in the next test, on 7 September, when two parachutes failed. Efforts to correct this problem took over two months. On 15 November, some four months after the full-scale emergency recovery system was supposed to have been qualified, the fourth drop was a disaster. When all three parachutes failed, the test vehicle was destroyed as it hit the ground. Clearly the system could not be relied upon. GPO directed McDonnell to furnish North American with a boilerplate spacecraft for further tests at some later date.13
These problems, however disheartening, should not have cast any shadow on the concept of a paraglider. The emergency parachute systems were intended only to back up testing; they were not part of the Gemini landing system. Yet the pattern of delays, errors, and malfunctions that marked North American's efforts to qualify the emergency system proved to be symptomatic of a lingering malaise. Paraglider advocates knew that the program would be made or broken, so far as Gemini was concerned, by the success or failure of flight testing, and time was limited. North American had been chosen over Ryan and Goodyear because of its first-rate job in testing the design during the summer of 1961.14 But on 28 November, scarcely a week after North American received word to go ahead with paraglider development, NASA notified the company that it had been selected as prime contractor for the Apollo spacecraft. The impact on paraglider was catastrophic. North American froze the number of engineers assigned to paraglider, then allowed even that group to decline. The quality of work suffered as well, becoming, in the opinion of one NASA engineer assigned to the program, "abysmal."15
The pattern of trouble sketched in emergency system testing persisted when North American began testing the paraglider itself by flying half-scale models with wings inflated and deployed before they left the ground. Scheduled to begin in May 1962, these trials got under way in mid-August at Edwards Air Force Base, 100 kilometers north of Downey. North American's first try, on 14 August, got nowhere. Because a plug pulled loose inside the capsule, the wing, which was tied down for takeoff, failed to release after a helicopter had towed it to the proper height. The wing released too soon in the second try, three days later, although the capsule did go brief it into a stable glide. North American also achieved a stable glide in the third flight, on 23 August, but an erroneous radio command caused the vehicle  to come down too fast and suffer some damage in landing. The fourth flight was postponed twice, each time because someone forgot to charge the battery. Towed aloft on 17 September, the vehicle failed to release on command, voiding the test. Twice in a row, short circuits forced the contractor to call off the fifth flight test, the second time on 21 September.16
That same day, James Chamberlin, MSC Gemini Project Manager, ordered North American to halt flight tests of the half-scale paraglider. He expressed "growing concern" over "the repeated unsuccessful attempts of S&ID [North American's Space and Information Systems Division] to conduct satisfactory predeployed half-scale paraglider tests." Flights were not to resume until the contractor had reorganized its paraglider project and could spell out just what it intended to do about the test vehicle's electronics and pyrotechnics and the company's own checkout and inspection procedures.17
North American had already made some moves along the lines Chamberlin demanded. The paraglider effort was raised to the status of a major program, and George W. Jeffs was named Paraglider Program Manager on 1 September 1962. Norbert Witte, the former project manager, stayed on as Jeffs' assistant.18 Jeffs was something of a corporate troubleshooter, and he had the respect of the NASA engineers working on paraglider.19 This augured well for the future, but, in the meantime, a fully successful flight test had yet to be performed.
North American reworked the half-scale vehicle in its plant, then shipped it back to Edwards Air Force Base on 15 October for another try. A bad ground transmitter stalled matters for a while but, on 23 October, the fifth test flight was a complete success.20 Even with all its problems, the series of tests had met its main goal, showing that the paraglider was stable in free flight.21 But predeployed flight testing ended more than two months late, and the crucial deployment flight tests - spreading the paraglider wing in flight - had not even begun.
In the meantime, other problems were beginning to compete for the attention of the overworked project office. Like the paraglider, ejection seats had been a controversial innovation in manned spacecraft, and their development problems also gave critics an early opening. The reasons were much the same. Both systems were a long step beyond current practice, both presented test problems not clearly related to their final roles, and both were subject to changing requirements that imposed makeshift adjustments, further complicating matters.
Although ejection seats were widely used in military aircraft, they were designed to give pilots a chance to survive, not to guarantee that survival. Manned spacecraft levied more stringent demands. Most critical was the "off-the-pad abort mode." Before liftoff, the spacecraft perched some 45 meters from the ground atop a shell filled with potentially explosive chemicals, the Titan launch vehicle.  However rigorous the precautions, there was always the danger of some mischance setting it off. For a length of time that might stretch into hours before they were airborne, the crew would be aboard with no recourse, should that mishap occur, save their ejection seats. The Gemini seat had to be able to propel itself from a starting point 45 meters in the air in a trajectory stable enough to get clear of an exploding booster and high enough to allow parachutes to open. No existing seat could do that, and developing one that could was the crux of the Gemini effort.22
McDonnell chose Rocket Power, Inc., of Mesa, Arizona, to supply the rocket catapult (or rocat) for the Gemini escape system.23 For the seat itself, McDonnell turned to Weber Aircraft, of Burbank, California.24 As luck would have it, the Naval Ordnance Test Station at China Lake in the middle of California's Mojave Desert had earlier constructed a 45-meter tower for Sidewinder missile tests. This tower was admirably suited for simulated off-the-pad ejection (or, acronymically, Sope) tests.25 Kenneth F. Hecht, who left the ordnance test station in January 1962 to take charge of Gemini escape and recovery systems, set up a special working group to oversee seat development and qualification.* He was convinced, and in this he was seconded by those who knew most about ejection seats, that the key problem was finding ways to control the relationship between the rocat's line of thrust and the shifting center of gravity of the seat-man combination while the rocket was burning. Without this control, a trajectory of the proper height and stability could not be achieved. This was one of the reasons why Hecht insisted the tests be conducted with a dummy in the seat, rather than with a solid mass. He also knew that haste was vital, since the seat design could not be settled until the answers were in.26
The first Sope test came off on schedule 2 July 1962, followed by four more over the next month. All produced their share of problems and mechanical failures, each dealt with as quickly as possible to get on with the next test. None of these mechanical problems much bothered Hecht and his colleagues, because they had their eyes on the dynamic problem of rocket thrust and center of gravity. They were concerned with ejection at this point, not the complete escape sequence through recovery, and thought they were close to solving that key problem.27 From this viewpoint, the first five tests were a success. But if the goal were seen as a complete system with all parts working as they should in the final version, the tests left much to be desired. The seat seemed to be turning into a maze of makeshift fixes, and the personnel recovery parachute system (the crewman's landing device) had failed twice.
 At an extended meeting in Houston on 6 and 7 August, the total system viewpoint prevailed. Sope testing was halted until a complete design of the whole system was ready and the personnel parachute had been fully tested.28
A month elapsed before McDonnell was able to report on 6 September that seat design and testing were complete, clearing the way for a new round of Sope trials. Tests on 12 and 26 September went well but highlighted a set of problems with the rocket motor. Some were functional and some structural, but all affected, however slightly, the direction of thrust and so made accurate control impossible. Testing stopped again, pending the availability of the rocat in its final form.29 This delay was much prolonged, lasting well into 1963.
Other major Gemini systems seemed less troublesome. Through the summer and early fall of 1962, such problems as appeared could be, and were, regarded as nothing more than the routine hurdles in a large program. One possible exception was the fuel cell, which, like paraglider and ejection seats, was new to manned spacecraft and had aroused some debate, at least in its General Electric version.
The basic source of electrical power in the spacecraft was to be batteries. The weight of ordinary batteries, however, became prohibitive as missions increased in length. Something more was needed, and the choice was fuel cells. That choice was resolved in January 1962. After analyzing the merits and defects of competing approaches, Robert Cohen of MSC strongly recommended the General Electric fuel cell as lighter, simpler, and more generally suited to Gemini needs than other designs he had investigated.30
In a fuel cell, hydrogen and oxygen react to produce water and heat. The unique feature of the General Electric design was its use of a solid ion-exchanging membrane in which electrolyte and water were chemically bound; most other cells diffused gases into a liquid electrolyte. A separate stream of coolant condensed the water produced at the cell, then removed it through a series of wicks to keep the reaction going at a constant rate. This used little of the cell's own power, in contrast to the gas-diffusion cells that required a complex self-powered process of flushing with hydrogen, condensation, and centrifuging to remove the water produced. General Electric had devoted intense research to the design since 1959 and had already set up a fuel-cell facility, the Direct Energy Conversion Operation in West Lynn, Massachusetts.31 McDonnell shared Cohen's view and formally recommended General Electric for a subcontract, to which NASA agreed.32
Nonetheless, in early 1962 the General Electric fuel cell was still no more than a laboratory device, however promising.33 NASA Headquarters was looking into fuel cells for Apollo, which raised some questions about Gemini's choice of General Electric. The Office of Manned Space Flight's survey of General Electric alleged that the company was  understaffed, slow in getting started, and unlikely to meet Gemini schedules - all this in addition to what seemed to be an untested and questionable design concept.34 Cohen responded to these charges for GPO. He saw no reason to doubt that General Electric would meet its commitments: the company was adding to its staff and improving its effort, which had only begun with an order from McDonnell two and a half weeks earlier. More important, the much tested General Electric design was at least as far along as any other and was inherently simpler to boot.35 That settled the issue.
As development got under way, General Electric began to run into problems that seemed to suggest that theory had outpaced practice. The most serious in mid-1962 was how to achieve a satisfactory bond between cell membrane and frame. Solving these problems appeared more likely to tighten the schedules than to threaten the program as a whole. In any case, the worst appeared to be over by the end of August.36
During the last half of 1962, the paraglider's troubles probably posed the greatest threat to an approved Gemini objective, that of land landing, although ejection seats and, to a lesser extent, fuel cells were also worrisome. The paraglider was a major new system that demanded a large-scale effort. Ejection seats and fuel cells, though not so novel, were still major innovations in manned space flight. In all three cases, the novelty of the application and the advance beyond current practice imposed a greater development effort than required for other Gemini systems. Given that fact, the problems should have come as no surprise. A quite unexpected source of trouble loomed in another quarter. The suitability of Titan II as a launch vehicle for manned space flight came into question.
Responsibility for developing the Titan II missile belonged to the Ballistic Systems Division (BSD), like SSD a part of Air Force Systems Command. Titan II research and development test flights began on 16 March 1962, with a launch from the Atlantic Missile Range in Florida. In its first flight, Titan II displayed a disquieting characteristic. A minute and a half after it lifted off, while the first-stage engine was still firing, the missile began to vibrate lengthwise like an accordion about 11 times a second for roughly 30 seconds. This was not likely to bother a missile too much, but it implied real trouble for a launch vehicle with a manned payload. The steady acceleration of a booster like Titan II pressed a crewman to his couch with about two and a half times the force of gravity at that point in a normal flight. Bouncing at an extra two and a half gravities (+ 2.5g) could badly hamper a pilot's efforts to respond to an emergency, a matter of special concern in Gemini since the crew played so large a role in flying the spacecraft.37
Titan II's longitudinal oscillations quickly acquired the nickname "pogo stick," soon simply Pogo. Its cause remained unclear, how to get  rid of it a matter of guesswork. By July, Pogo was becoming a regular topic at MSC's weekly senior staff meetings, and BSD had formed a special Committee for Investigation of Missile Oscillations.** 38 The problem turned out to be surprisingly easy to solve for the missile: higher pressure in the first-stage fuel tank cut Pogo in half during the fourth test flight, on 25 July, although nobody was quite sure why.39
There were some ideas, however. Martin engineers thought the culprit might be oscillating pressure in propellant feedlines, analogous to the chugging of water in pipes, or "water hammer." This suggested the use of something like the surge tanks familiar as devices to stabilize pressure in the flow lines of hydroelectric plants and pumping stations. Martin proposed to install a surge-suppression standpipe in the oxidizer line of a later Titan II. MSC endorsed the plan, and BSD agreed. By the end of August, GPO was cautiously optimistic. The lowered Pogo level of plus or minus 1.25g achieved in the fourth Titan II test flight was still too high for manned space flight, but the water hammer analogy at least suggested an answer.40
GPO was also watching another problem. In two of its first four test flights, Titan II's second-stage engine failed to reach full thrust. The causes appeared to be different in each case and unrelated to one another. Just how serious this might be could not be foreseen. Much depended upon whether or not it recurred, and GPO adopted a wait-and-see stance.41
Project Gemini's technical problems in the summer and fall of 1962 might have aroused more concern if a far more serious threat had not intruded. The financial structure of the program began to totter. Two circumstances combined to produce a major crisis. On one hand, Gemini contractors were spending money at a much faster rate than the project office had expected. On the other, Congress was slow to approve NASA's appropriation for fiscal year 1963, which restricted the funds available to Gemini. However serious development problems might be, or become, they could always be resolved if there were enough money. But now the question was how to spread limited funds over an ever more costly program.
The Budget Crisis
The pattern of program growth and cost increase revealed during the spring of 1962 persisted, and with the same shortage of dependable information. To NASA's repeated pleas for more funding data, McDonnell regularly denied that any existed.  In mid-July 1962, three months after its first budget proposal, the company could still not provide a detailed forecast of program costs because "cost projections from suppliers and subcontractors are currently unavailable as purchase order values continue to change and negotiated costs have not been established."42 In August, when MSC and McDonnell began working out the final terms of the spacecraft contract, the contractor proposed a startling total of $498.8 million, double NASA's first estimate in December 1961 and more than $100 million higher than the company's own April 1962 proposal.43 Hard negotiation brought the new figure down to $464.1 million,44 but efforts to agree on a final price were suspended before the end of August because the whole Gemini program was in trouble.
Other costs were also on the upswing during the summer and early fall of 1962, though not as spectacularly as those for the spacecraft. SSD's March 1962 figure of $164 million for the launch vehicles  topped $170 million by September.45 Less than a month later, SSD submitted to NASA a formal revised budget of $172.61 million.46 Word reached MSC in July that the Atlas-Agena for Gemini now had a price tag of $12.3 million over its earlier total,47 and this despite the fact that NASA had deleted the three spares to cut the number of Atlas-Agenas on order from 11 to 8.48 A special briefing for NASA Administrator Webb on 28 September revealed that Project Gemini might cost as much as $925 million before it was over, 25 percent higher than Webb had been told in May it was going to cost and 75 percent more than MSC's first estimate.49
Such fast-rising costs would have been bad enough at any time. Now they presaged disaster, since Congress had not yet acted on NASA's appropriation for fiscal year 1963 (which began on 1 July 1962). Without an approved money bill, NASA was compelled to carry on under a joint congressional resolution that provided enough money to support projects at roughly the same level they had enjoyed the year before but not enough to cover increases.50 Gemini's status was all the more threatened because it had not even appeared in the 1962 budget. NASA had found enough money to get Gemini started, but that was a makeshift that could not support an ongoing program.
The bill that authorized NASA's funds was signed into law on 14 August, but the bill to appropriate that money was yet to come. Congressional action on NASA's 1963 appropriation was not completed until 25 September. The figure was $3,774,115,000, $113,161,000 less than NASA had asked for and $70,000,000 under the total authorized in August.51
This delay prevented the Office of Manned Space Flight in Washington from giving MSC the normal authority to spend money on the basis of the full year's budget. Instead, that authority was being granted on a month-to-month basis.52 Monthly funding brought anguished complaints from contractors, as expenses constantly threatened to outstrip the resources available to pay for them. By October, MSC was being bombarded with telegrams, each with urgent demands for full and quicker funding.53
Lack of an appropriation also prevented NASA from adopting a final financial operating plan (FOP) for fiscal year 1963. Each center prepared an annual FOP to be approved by NASA Headquarters for allotting funds at the start of the fiscal year.54 To meet the impending crisis, Associate Administrator Seamans imposed a ceiling of $1.51 billion on NASA research and development expenditures for the coming year. By this time, however, estimated funding needs for this purpose had already exceeded the figure first presented to Congress and now stood at $1.91 billion. Manned space flight chief Brainerd Holmes warned Seamans that current schedules could only be met by a supplemental appropriation from Congress. In the meantime, Holmes directed MSC to prepare two separate fiscal-year 1963 FOPs: one staying within the Seamans-imposed ceiling, the other geared to actual needs. For Gemini, this meant a limit of $234.1 million against a needed $299 million. Holmes predicted a severe setback to program schedules if the smaller budget prevailed: a three-month delay in the first launch and in the first long-duration flight, an extra ten-month wait for the initial rendezvous mission, and no paraglider before the third flight.55
Hopes for meeting the higher budget were dashed when President Kennedy rejected NASA's case for extra funding. Holmes notified MSC on 9 October that its funds for fiscal year 1963 would be limited to $660.1 million. He directed the center to prepare new schedules to reflect this limit, voicing the somewhat forlorn hope that the unavoidable delay of several months might be made good if "later developments make it possible for the Administrator to obtain a FY 63 supplemental."56
The new ceiling was $27 million less than MSC had planned for under the earlier Seamans ceiling. The situation was now critical. Already tight at the level of $687 million, a budget of $660 million was nearly crippling. And Project Gemini bore the full brunt. Upon first hearing of the newly reduced budget, MSC planned to split the $27 million cut between Gemini and Apollo. Washington, however, ordered Gemini to take all the losses. Wesley L. Hjornevik, MSC's Assistant Director for Administration, evaluating the situation for the senior staff on 19 October, saw no way out of this dilemma except to curtail Gemini sharply. "It appears", he glumly remarked, "that the consequent reduction to Gemini can only come by dropping paraglider, Agena, and all rendezvous equipment."
Further complicating matters was the rate at which Gemini was piling up costs, a rate much higher than expected. Hjornevik pointed out that the program seemed to be costing $15 million a month, rather than the planned $11 million.57 A budget memorandum that reviewed Gemini funding during the first quarter of fiscal year 1963 described as "an area of growing concern and one which can no longer be left unattended" the speed at which costs for spacecraft, paraglider, launch vehicle, and target vehicle were growing. The FOP could not "support acceleration of cost rates so projected by these contractors. Unless appropriate direction is given to the contractors to restrict this buildup or a Gemini reprogramming action is effected immediately then funding difficulties will commence during the second quarter."58
The project office had already moved to reprogram Gemini, to alter the course of the program and compel the contractors to  conform to the newly limited budget. Reprogramming was much more drastic in some areas than in others. Paraglider escaped almost untouched. McDonnell's spacecraft effort took some trimming but remained much what it had been. The launch and target vehicle programs, the Air Force portion of Gemini, endured the most far-reaching changes. Plans for testing the Gemini launch vehicle were sharply cut back. Target vehicle testing was even more drastically curtailed; for some months, in fact, whether Agena still had a Gemini role was an open question.
Realignment of McDonnell's work began first. Spokesmen from McDonnell and its subcontractors met in Houston at MSC on 24-26 August and again on 6-8 September. They agreed to limit the scope of development for some spacecraft systems and ground equipment.59 But MSC Director Gilruth told Walter Burke, McDonnell's spacecraft chief, not to do anything right away. When Gilruth talked to Burke on 8 September, the financial situation was still fluid enough to warn against too-hasty action. By the end of the month, however, prospects for any quick easing of the money crisis were fading. Burke flew to Houston to see Gilruth and Chamberlin on 28 September. Gilruth told Burke to carry out the earlier agreement on the revised scope of the program. Burke set his staff to work that same day on the necessary paperwork, wiring the subcontractors formal notice of their altered responsibilities and drawing up the required purchase order changes.60
Reprogramming at McDonnell in St. Louis was mainly a matter of making some adjustments. The company cut back its own and its subcontractors' quality assurance and reliability programs, reduced the number of published reports, decreased the number of spare parts to be maintained, trimmed the amount of engineering data and support required of subcontractors, and limited its support at Cape Canaveral. The net result of these changes was to slice $26 million from the $464 million that McDonnell thought its part of the project would cost, bringing the total down to $438.2 million.61
The largest savings in spacecraft development were to come through lessened testing by subcontractors. Teams from GPO spent much of October on two-day trips to major spacecraft subcontractors.* At each plant, they reviewed in detail the effect of various forms of  systems failures, plans for qualification and reliability testing, and test facilities required. In general, they agreed that reliability testing could be sharply curtailed at the expense of slightly increased qualification testing. Qualification tests ensured that something worked; they usually preceded reliability tests, which made sure that something worked consistently. Assured reliability could thus be gained from augmented qualification tests.62 Concerned by the way the program had grown, GPO also asked McDonnell for prompt notice of any future action that might affect contract costs or schedules.63
Spacecraft reprogramming was largely complete by mid-October, but the project office saw some further trimming possible in McDonnell's test program. After a review of its plans for structural tests of the spacecraft, the contractor concluded that one of the four programmed static articles might be dispensed with, and GPO agreed.64 The project office also suggested that Project Orbit might be canceled, a view McDonnell opposed. The dispute was eventually resolved with Orbit restricted to testing the spacecraft's heat balance and renamed "spacecraft thermal qualification test."65
Another casualty of Gemini's financial straits was a lately revived lunar landing scheme. This time the impetus had come from NASA Headquarters in the person of Joseph F. Shea, newly appointed Deputy Director for Systems in the Office of Manned S ace Flight. Shea wanted McDonnell to study using a Gemini spacecraft as a lunar logistics and rescue vehicle, a possibility also under study during that summer by the Space Technology Laboratories.66 The eight-week McDonnell effort explored the concept of a two-man command module, evaluated using a Gemini spacecraft to land two men on the lunar surface, and looked at the design changes needed for such a mission.67 Meanwhile, GPO computed the cost of buying extra spacecraft.68 McDonnell submitted its findings to NASA Headquarters in November 1962.69 Whatever chance the scheme may have had, however, vanished in the wake of Gemini's money problems, and the idea once again came to nothing.70
With the spacecraft taken care of by mid-October, the project office turned to launch vehicle programming. Limited funds compelled GPO to restrict 1963 costs to $59.28 million, some $10 million below its earlier plan and $18 million less than the $77.5 million SSD now claimed to need.71 Chamberlin wired Richard Dineen, SSD's chief of Launch Vehicle Development, on 19 October to apprise him of the new funding limits. GPO believed that Gemini's major goals might still be met despite shortage of funds. The key was a sharp cutback in testing, especially where it involved repeated engine firing.72 To Dineen, these changes seemed drastic, and he asked Chamberlin for a fuller explanation.73 Chamberlin insisted that there was no hope of more than $59.28 million for 1963, which meant the planned test program  had to be reduced and, in part, canceled. He asked Dineen for an early meeting to decide how to put these changes into effect.74 SSD still objected.75 Chamberlin persisted, wiring Dineen on 16 November that a meeting to review the launch vehicle test program was urgent and "should take precedence over other SSD/Aerospace/Martin/Aerojet Gemini commitments."76 The meeting finally convened on 27 November.
The proposed changes were indeed drastic. The revised engine program called for only 34 test firings, less than a fifth of the number originally planned. This would yield all the data needed at a saving of several million dollars, if effort were focused on thorough development and qualification to make sure each part worked and would keep on working.77 Sound engineering, in other words, made reliability a natural product of development and qualification. SSD and its contractors could scarcely quarrel with this view, but they tended to see reliability in more statistical term - a part was reliable if it failed no more than some very small percentage of the times it was tested. The issue was not merely philosophical. Proving reliability statistically meant more tests, more equipment, and more money.
What was true for engines was also true for other parts of the launch vehicle. Martin's reliability program was budgeted for $2.7 million, but the GPO approach, by concentrating dollars on qualification rather than on reliability testing, could cut that figure in half.78 Further study convinced Chamberlin that most of the planned prelaunch firings of the complete launch vehicle could also be safely discarded, and they were.79
NASA's budget crisis in the fall of 1962 never posed any real danger to Project Gemini itself. Work on spacecraft and launch vehicle was simply adjusted to meet an unexpected funding squeeze. Whether the Gemini that emerged from reprogramming would be the same project that had been planned, however, was another question. Tight money threatened to deprive Gemini of its chief objective, the development of orbital rendezvous techniques. For several months the role of Atlas-Agena in the program was in jeopardy, as NASA Headquarters debated dropping it, cutting it back, or keeping it with whatever slippage restricted funding entailed. The choice was not made any easier by the complex management structure of the target vehicle program. Two organizations, Marshall and SSD, stood between GPO and Lockheed, Agena's builder.
Word of tight budgets and a need to cut costs had reached Marshall's Agena Project Office by early October 1962 but was slower getting to SSD.80 The first firm notice that the Atlas-Agena program was to endure something more than a routine economy drive came on 23 October, when Chamberlin wired Friedrich Duerr, Agena systems manager at Marshall, "to reshape and reschedule the Atlas-Agena to conform to budget limitations.  MSFC is further directed to establish accounting procedures and funds expended monitoring procedures to assure that Agena development is prosecuted within the established fund limitations."
GPO had just completed a detailed study of changes that might be made in the Agena program to keep costs within budget limits. It concluded that $16.7 million could be sliced from the 1963 Atlas-Agena budget, dropping it from $27 million to $10.3 million.Chamberlin presented Duerr with the $10.3 million figure as a funding limit for fiscal year 1963, as part of an overall goal to reduce the cost of development by a third. For Agena, like Titan II, the savings were to be found mainly in less engine test firing and more built-in reliability. But Agena faced sterner sanction - no more money and all work stopped until reprogramming was complete.81
Duerr passed the word to the Air Force,82 although, as he informed Chamberlin, GPO's view of the savings that might be achieved was "optimistic" and the changes could only mean a long delay in the development program.83 Reprogramming began with a meeting in Houston on 25 October to discuss plans and schedules. What reliability meant emerged as the central issue, just as it did for Titan II. A second meeting, to agree on a specific plan, was set for 2 November.84
Before that meeting convened, however, the real need for Agena in the Gemini program was called into question. In mid-1962, NASA had decided in favor of the lunar orbit rendezvous scheme for the Apollo lunar landing. That tentative decision was confirmed on 24 October by the findings of a manned lunar landing comparison study.85 At a meeting of the Manned Space Flight Management Council six days later, Holmes raised the issue of Gemini objectives in light of this decision. Shea reviewed Gemini's aims and claimed "that all of these objectives appear to be possible of achievement without use of the Agena in the program." MSC Director Gilruth disagreed, and an inconclusive debate over the fate of Agena followed. Although he knew that time was running out, Holmes asked Gilruth to study the matter further.86
Meanwhile, the second reprogramming session convened at the Lockheed plant in Sunnyvale, California. The monthly spending rate under the Gemini-Agena contract had reached $2 million during October. The limit for November, however, was fixed at $650,000, and Lockheed was instructed to stay within it. Lockheed spokesmen protested, claiming that Bell Aerosystems, the engine subcontractor, could not produce engines for an October 1964 launch if funds were so restricted. Chamberlin told them they had no choice - they must find ways to stay within the fixed limits. Lockheed had a week to provide a rough cost estimate for the revised program to SSD, which would turn its findings over to Marshall's Agena Project Office, which, in turn,  would pass its findings up the line to GPO. A final meeting to coordinate the changes was scheduled for 20 November.87
Duerr reminded Chamberlin that limited funding was bound to cost time, perhaps as much as 14 months, in Agena development. Extra money - $12.7 million instead of $10.3 million for the current fiscal year would hold the loss to a less painful five and a half months.88 But even at that, it would still be "a maximum risk program. That is to say that the target vehicle program has been minimized and no allowance is made for contingencies that may arise which would adversely affect costs and schedules."89 Chamberlin knew as well as anyone that time was being traded for money, but his hands were tied. A financial operating plan for 1963 had yet to be approved. Whether Agena could even be kept in the Gemini program - and not the precise level of funding - was the crucial question.
At a meeting of MSC's senior staff on 9 November, Chamberlin strongly objected to Shea's claims at the Management Council meeting on 30 October. Shea, and others in NASA Headquarters, believed that rendezvous goals might be met by using a "piggyback" rendezvous package, carried aloft in the adapter section of the spacecraft and then ejected in orbit to serve as a stable but non-maneuverable target. Chamberlin dismissed the piggyback technique as inherently limited in contrast to the stabilized and maneuverable Agena. He also believed that the package would be far heavier than its proponents claimed. André Meyer, chief of GPO administration, figured its weight at 180 kilograms, twice the Headquarters estimate. If that were true, it could mean the end of paraglider. Meyer thought the package would cost as much as Agena, although without the problems and expenses of separate launches.90
MSC had been thinking along similar, but much more modest, lines. A study issued on 28 March 1962 had concluded that a piggyback rendezvous target could provide useful data. A month later, McDonnell had suggested testing the spacecraft rendezvous radar and maneuvering systems on an early Gemini flight with what it called a "Rendezvous Evaluation Pod (REP)." This was a small battery-powered module with a radar transponder, radar beacon, and flashing light, the whole package weighing about 30 kilograms and designed to give the pilots a chance to practice terminal rendezvous maneuvers with their spacecraft. In June, MSC had told McDonnell to go ahead with design and development. The REP would be carried on the second and third Gemini flights. Planning was largely complete by the end of 1962, with Westinghouse, the rendezvous radar subcontractor, responsible for components and McDonnell for the package and its ejection.91 This, however, amounted to little more than an experiment, intended to prepare for, not supplant, the Agena rendezvous missions.
 On 16 November, Wesley Hjornevik, chief of MSC administration, reported to the senior staff that a financial operating plan for fiscal year 1963 had finally been approved. Agena funding, however, had been withheld.92 Target vehicle reprogramming went ahead, with the final meeting on 20 November in Houston. Lockheed's new program was accepted. The major changes made reliability demonstration part of development and qualification testing, cut engine development testing to the bone, and trimmed production lead times to keep down 1963 expenses. This last meant chiefly that Lockheed was to work at a reduced level through the rest of calendar year 1962, then return to full effort on 2 January 1963. The program would be four months late, but its total cost could be as low as $44.1 million, $32.7 million less than estimated before reprogramming began.93
Gilruth outlined the revised Atlas-Agena plans to the Management Council on 27 November, with a sharp reminder that "it is very critical that a decision as to the inclusion of the Atlas-Agena in the program is reached soon if the Agena target schedule is to be maintained." Holmes promised a ruling by 10 December.94 Not only had the fate of Agena become a matter of public speculation, but lack of funds threatened to stop the target vehicle even before anything was decided.95
The decision came early but turned out to be only a stopgap: $900,000 for another month. This brought the total for fiscal year1963 to $4.9 million; the balance of the planned $10.3 million for Atlas-Agena remained in abeyance.96 Shea, who had proposed dropping Agena from Gemini, told a reporter that NASA was thinking about several alternatives to simplify the rendezvous concept, with a decision due shortly. He gave Agena only a 50-50 chance of staying in the program.97 Agena's fate was in the hands of a NASA-wide committee, which Shea himself headed. A thorough investigation, bolstered by the well-informed and forceful case presented by James Rose, the GPO member, decided the committee in favor of Agena. A wire from Washington on 21 December authorized MSC to spend the full $10.3 million needed for the reprogrammed Agena in fiscal year 1963.98
MSC also took over management of the Gemini Agena program. NASA decided to transfer all its Agena programs from Marshall so that that Center could focus on the Saturn launch vehicle for Apollo. Lewis Research Center in Cleveland, Ohio, assumed control of all NASA Agena programs except Gemini, which went to MSC.99 MSC, now dealing directly with SSD,100 took formal charge of the Gemini Atlas-Agena program on 14 January 1963, with active advice from the Marshall office for the next month and a half.101 Lockheed and SSD also adjusted their management relationships. The Gemini manager at Lockheed, Herbert Ballard, moved up a notch; he now reported directly to the head of Lockheed's Medium Space Vehicles Programs. SSD followed suit by upping the rank of its program manager from  captain to major; and Major Charles A. Wurster took over the reins.102
Since the only function for Atlas in Project Gemini was launching the target, its fate waited on Agena's. But Atlas, too, suffered in NASA's fall budget crisis. On 25 July 1962, NASA Associate Administrator Seamans had agreed to support Air Force development of a standard Atlas launch vehicle, SLV3.103 By the time the Department of Defense had drafted a formal Memorandum of Agreement and forwarded it to NASA on 21 August, NASA's funding outlook had so deteriorated that it could no longer contribute to the program. Seamans restated NASA's interest in SLV-3 development but declined to commit the roughly $10 million that was to have been its share of the cost.104
Reprogramming raised the possibility of using surplus Atlas boosters from the Mercury program in Gemini. Chamberlin asked SSD for an opinion. A report to the Atlas-Agena reprogramming meeting of 20 November was favorable. Chamberlin then asked the Atlas contractor, General Dynamics/Astronautics, for a formal proposal.105 The results made conversion look promising economically. Three converted Mercury boosters could be had for a net cost of $3.364 million, as opposed to $5.4 million for three new standard Atlases.106 But by the time those figures were submitted on 13 February 1963, Gemini's budget crisis was over, and NASA was back in the standard Atlas development program. In December, Seamans had formally committed NASA to pay its $10 million share.107
The Prospect for 1963
With reprogramming completed, Gemini's prospects looked reasonably bright as 1962 gave way to 1963. The crisis through which the program passed in the last quarter of 1962 was monetary, not technical. That crisis weathered, the technical problems looked less menacing as well. In his report to the Management Council on 18 December, Gilruth noted that Gemini still had a number of technical problems, but all, he judged, "are being actively pursued and none appear to be unresolvable."108
Gemini had lost time, though. The new Gemini program was chiefly a response to budget limits imposed from outside, compounded by sharply rising costs. Its immediate goal was cutting back expenses during the current fiscal year, and this meant slowing down the program. But a longer program, despite the curtailed and streamlined development that emerged from Gemini's fall crisis, was likely to cost more in the long run. Whether the total cost of the program would really rise, and how much, could only be answered with the passage of time.
 The effects of reprogramming on Gemini schedules were easier to define. Gemini was going to lose four months. The new date for the first launch was December instead of August 1963. It was now an unmanned suborbital qualification test. McDonnell had proposed in July 1962 an extra mission that it called Flight No. 0, a suborbital shot to precede the first planned mission. On 20 July, Burke and Chamberlin agreed to replace the planned unmanned orbital flight with the suborbital flight as the first mission (a slightly revised version of the Mission 0 plan). It was to be a ballistic test to investigate spacecraft heat protection, to integrate launch vehicle and spacecraft preflight and launch operations, and to obtain data on spacecraft structure and systems.109 All other launch dates were set back four months. The second flight - manned orbital qualification followed the first by three months, in March 1964, with the rest of the missions coming every two months until the 12th and last, now scheduled for November 1965.110
By December 1962, everything seemed to be under control again. But while the project office and MSC were wrestling with the hard tasks of fitting development work to the limited money available, NASA Headquarters found itself fending off quite a different threat - perhaps the least expected of all. The Department of Defense was making gestures toward taking over Project Gemini.
Challenge and Change
 Going into its second full year, the Gemini Project Office had just finished moving into new quarters. The office had been split between two sites, with project manager James Chamberlin at the Farnsworth & Chambers building (interim headquarters for the Manned Spacecraft Center) and the rest of the Gemini office across the Gulf Freeway in the Houston Petroleum Center. By December 1962, the office had doubled its original staff of 44 and outgrown its former space. Chamberlin and all of his people moved into the old Veterans Administration building on the edge of downtown Houston by 10 December, and the Gemini Procurement Office of MSC's Procurement and Contracts Division followed in March 1963.1
Putting all of Gemini under one roof no doubt helped as the program became more taxing. The early months of 1963 soon showed that many technical problems were far from resolved end that the question of money was not fully settled by the reprogramming efforts. But Gemini's first big worry of the new year had little to do with technology or funding. The Air Force had long been interested in orbital rendezvous and manned space flight, as reflected in its unmanned satellite interceptor project (Saint) and the maneuverable manned Dyna-Soar program. That interest now expanded to include Project Gemini.
"Blue Gemini" was the tag name for an Air Force manned space flight program to develop rendezvous, docking, and transfer for military purposes,  using Gemini-type spacecraft. The germ of the idea first surfaced in February 1962, during congressional hearings on the defense budget, as part of a far-ranging Air Force Space Plan for the development of military space technology over the next 10 years. The concept became firmer in June, when the Air Force Space Systems Division (SSD) began working on plans to use Gemini hardware as the first step in a new Air Force man-in-space program called Mods (Manned Orbital Development System), a kind of military space station with Gemini spacecraft as ferry vehicles. The term Blue Gemini first showed up in August as part of a more specific proposal to fly six Gemini missions with Air Force pilots in a preliminary orientation and training phase of Mods.2 Blue Gemini was neither clearly defined nor officially sanctioned. Air Force opinion was divided on the best approach to the goal of military manned space flight. Some, like Air Force Chief of Staff Curtis E. LeMay, wanted nothing to do with Gemini, fearing that entanglement in the NASA program might jeopardize Dyna-Soar. Others, like Major General Osmond J. Ritland, deputy for manned space flight in Air Force Systems Command, urged a more active Air Force role in Gemini, since Dyna-Soar would not fly for at least two years. Civilian officials in the Pentagon remained skeptical of any military man-in-space proposals, for much the same reason that had tended to block such efforts all along: the absence of any clear-cut military need for manned operations in space.3
By the fall of 1962, the situation was in flux. The Saint program suffered a sharp cutback in December, following cost overruns and schedule slippages. This made Gemini look even more attractive to those Air Force planners still convinced of the military importance of orbital rendezvous but now lacking a program to test their ideas. Techniques for rendezvous between remote-controlled machines, as in Saint, would differ from those suited for manned rendezvous, but manned work in space looked more exciting anyway. Dyna-Soar, a winged glider boosted into space by a Titan III to orbit Earth and fly back to an airfield landing, had lost much of its promise as a result of changes and delays. The exciting potential of such a program, when it took shape in the late 1950s, looked much less impressive by the end of 1962, especially in contrast to Gemini. No decision had yet been made in the Department of Defense, but the entire military manned space role was under review and forecasts of Dyna-Soar's extinction were rife.4
Meanwhile, the Air Force role in Project Gemini was limited to the one set out in the "NASA/DOD Operational and Management Plan" of December 1961, SSD acting as contractor to NASA for launch and target vehicles.5 The idea of Blue Gemini - a larger part for the Air Force in the program - had a good deal of support within NASA,  especially from MSC Director Gilruth. Gemini had been designed as an operational spacecraft, and the Air Force was the most likely customer. The Air Force could also be expected to pay for what it wanted, and Gemini could use an infusion of Defense funds. At a meeting in November 1962, Chamberlin and some of his staff described salient aspects of Gemini to a group of SSD representatives.* This meeting was intended to lay the groundwork for coordinating Air Force planning with MSC and to set up channels for future collaboration.6
NASA Administrator Webb and Associate Administrator Seamans visited the Pentagon for a talk with Roswell L. Gilpatric, Deputy Secretary of Defense, in an effort to convince Pentagon planners that an augmented role for the Air Force in Project Gemini was a good idea. Chance brought Secretary of Defense Robert S. McNamara to the meeting. His response to their offer was more than the two NASA spokesmen had bargained for; it took the Air Force by surprise as well. McNamara not only welcomed the idea of cooperation - he proposed merging the NASA Gemini program with the Air Force project and moving the combined effort to the Department of Defense.7
That was too much for NASA. W. Fred Boone, a retired admiral who had become NASA Deputy Associate Administrator for Defense Affairs on 1 December, took charge of building the case against Gemini's transfer to the Air Force. In NASA's view, not surprisingly, "the Gemini program should continue under the direction of NASA." The keystone of NASA's case was that Gemini was integral to the step-by-step climb from the first moves into space in Mercury to the final landing on the Moon in Apollo. Any delay in Gemini might delay the lunar landing. Increased Air Force participation "to further DOD objectives in space" was all right, but it must not hamper NASA in promptly carrying out the Gemini program.8
To support his position, Boone asked each of the NASA staff offices for a statement on the effects of an Air Force takeover of Gemini. The replies stressed the clear threat that such a move might disrupt NASA's manned space flight effort in general and the manned lunar landing program in particular. Beyond this most pressing danger, they feared nasty responses from outside NASA: increased criticism from a Congress already perturbed by signs of military influence in NASA programs; rising concern from a public disturbed by questions about the viability of a civilian space program; and growing disquiet in foreign nations about the United States being a peaceful explorer of space,  which carried the added threat that some countries might expel NASA tracking stations from their territories.9 After going over these arguments, Boone concluded:
It is in the national interest that the management of Project Gemini remain with NASA's Manned Spacecraft Center. A change in program management would seriously delay and substantially increase the cost of the manned lunar landing program. Any delay would reduce the chances that the United States will make a manned lunar landing before the Russians do.
A much better choice than giving Gemini to the Air Force would be to enhance the role of the Air Force within the framework that already existed.10
Just as surprised by the McNamara proposal as NASA was the Air Force, which shared NASA's distaste for a Gemini takeover, partly because it might jeopardize Dyna-Soar, partly because the costs of a few fully "blue" Gemini flights would far outweigh any foreseeable gains.11
NASA's arguments for keeping Gemini seemed convincing enough when presented to top Pentagon officials on 9 January 1963, bolstered as they were by the Air Force's unwillingness to take the program. McNamara and Gilpatric readily agreed not to press for transfer of Gemini. However doubtful the future role of military man-in-space, they thought the Air Force remiss in failing to accept NASA's offer of a larger part in Gemini. That was what McNamara now wanted as a formal pact between the two agencies; and he wanted it soon, before he began to present his case for the coming year's Defense budget to Congress on 21 January. Perhaps as much as $100 million in Defense funds could go to Gemini. McNamara's key idea was a joint management board to run the project and he promised to forward a draft agreement soon.
A jointly managed Project Gemini had no more appeal for NASA than an outright transfer. Boone dismissed the proposed board as "a completely unnecessary organizational appendage"12 even before he saw the promised draft. It arrived on Saturday, 12 January, and did nothing to soften Boone's judgment. Claiming that "both parties [DOD and NASA] consider that the national interest requires the program to be jointly managed," McNamara proposed an eight-man Gemini Program Steering Board to approve program and funding plans, to safeguard both Defense and NASA experimental objectives, and to resolve schedule and resource conflicts. Although GPO would report to the new board, project management would remain unchanged. Defense intended to pay for its enlarged role with money for current Gemini needs, as well as future board-approved changes.13
NASA's top management discussed the plan on Monday afternoon,  14 January, and Boone drafted a reply. McNamara's "joint management," in Boone's view, equaled "rule by committee," which "in this case would be ineffective, uneconomical, and in fact unworkable." Changing Gemini also threatened Apollo and might cost the United States its chance to win the space race. The proposed joint board also violated the Space Act of 1958, certainly in spirit and probably in letter. There seemed to be room enough for the Air Force in the current Gemini setup. If not, a joint planning and review (as opposed to management) board to advise the NASA Administrator ought to serve the purpose. Boone concluded by stating "NASA's strong interest in the Dyna-Soar program," hinting that NASA would endorse the Air Force project if Defense relaxed its demands on Gemini.14
NASA's revised version of the Defense draft altered enough words and accents to transform its meaning. Gone was any hint of "joint management." The steering board had become the Gemini Program Planning Board, limited to watching over a program of Gemini experiments. There was no mention of approving program plans or allocating resources. At most, the board could inform the NASA Administrator and the Secretary of Defense of such problems as planning defects or schedule conflicts. NASA repeated, and stressed, its claim to sole control of Gemini. GPO would not report to the board. The Air Force would be restricted to joining "in the development, pilot training, preflight check-out, launch operations and flight operations of the Gemini program to assist NASA and to meet the DOD objectives," just as it had been doing.15
The Defense Department accepted NASA's terms in a series of meetings between spokesmen for the two agencies over the weekend of 19-20 January. Willis H. Shapley, Deputy Chief of the Military Division of the Bureau of the Budget, arranged the meetings and prepared a series of notes designed to clarify the intent of the agreement proper and to distinguish it from some rumored proposals that had surfaced in the press. Aviation Week and Space Technology, for example, had reported in its issue of 10 December 1962 that NASA and the Air Force had agreed on a cooperative Gemini/Blue Gemini program: NASA would fund Gemini development and fly the first missions; the Air Force would fly copilots on one or two of the early missions and buy the last four or five Gemini spacecraft for its own flights plus a few extra beyond the twelve NASA had ordered.16
Shapley's notes mostly covered management relations between NASA, Defense, and the proposed Gemini Program Planning Board; but they also touched on funding and the domestic and foreign impact of the new arrangements. Gemini was not to be thought of as a joint program, but rather as a program serving common needs, with the Department of Defense paying for the military features, NASA in full  charge of the program, and the role of the board strictly advisory. Defense funds were to be used for nothing but the changes geared to military needs; the money was specifically not to be used to speed up the current NASA program nor to make up slippages and overruns. No major change in policy toward the Air Force role in space was intended, and the new agreement was to be presented to the public as the latest in a series of efforts to enhance cooperation and to avoid duplication between NASA and the Pentagon.
Webb signed the revised agreement and sent it, along with a slightly edited version of Shapley's notes, to McNamara on 21 January. The notes were not part of the formal document, but they helped fill out the record of understanding between the two agencies.17 The new pact was made public the next day. Webb and McNamara "joined in stressing the national character and importance of the Gemini project" and in their determination to see it "utilized in the national interest, and to avoid unnecessary duplication of effort in this area as in all others" - citing the agreements on the management of Cape Canaveral (also announced on 22 January) and on such earlier undertakings as Dyna-Soar and the national launch vehicle program as examples of similar cooperation.18
How a seemingly larger Defense role in Gemini might affect international opinion was the subject of still further concern. NASA assured the State Department that Gemini's goals remained unchanged, its peaceful scientific character unaltered. NASA still ran Gemini and planned to make Gemini's scientific data as widely available as Mercury's. The new agreement simply augmented military support of the same kind already known to the manned space flight program. Gemini was still open, NASA still managed it, and its foreign network stations would have no military personnel except medical.19
Although the NASA/Defense agreement of 21 January left NASA clearly in charge of Gemini, rumors of an Air Force takeover persisted.20 Real changes were small. The major innovation was the Gemini Program Planning Board, a strictly advisory body whose planning was to be confined to military experiments for Gemini flights. Its co-chairmen were Seamans for NASA and Brockway McMillan for Defense. McMillan was Assistant Secretary of the Air Force for Research and Development. Holmes and Boone were the other NASA members; and the Department of Defense named General Bernard A. Schriever, Commander of Air Force Systems Command, and Lawrence L. Kavanau, Special Assistant for Space to the Director of Defense Research and Engineering. The group held its first meeting on 28 February 1963 at NASA Headquarters in Washington.21 The board in this as in later meetings did attend to the place of military experiments in Gemini. But experiments did not remain its only concern, nor did they turn out to be the board's signal contribution to Gemini.
 The dispute between NASA and the Department of Defense about who was to have the last word in Gemini, whatever might be its long-range impact, agitated only the highest echelons. MSC engineers knew little of what was going on and, in any case, had their hands full with their own problems. Gemini reprogramming had slowed the rate at which money was being spent, but costs still spiraled upwards. Although stretching out the program was bound to offset immediate savings by larger total costs unless parts of the program were chopped out, the size of the increase soon surpassed anything that might have been expected. Meanwhile the revised program suffered from the growing severity of the technical problems that had afflicted it before and during the fall budget crisis. Paraglider testing and Titan II anomalies loomed largest.
Despite some talk about dropping paraglider from Gemini to meet fiscal constraints, paraglider development came through largely unscathed. While other major systems suffered more or less drastic cutback paraglider's budget expanded. By the end of 1962, contract changes and overruns had raised the price of the current phase of paraglider development from four and a half to over seven million dollars.22
North American Aviation, the paraglider contractor, was still having problems with flight testing. The success of 23 October 1962, which concluded the test series of a half-scale model launched with its wing already deployed, proved only a respite. The next step was trying to deploy the wing in flight. North American refitted the half-scale test vehicle at its plant in Downey, California, and shipped it back to Edwards Air Force Base for its first flight test, scheduled for 27 November. The all-too-familiar pattern of minor problems, mostly electrical, delayed the flight day by day until 10 December, and then the results were disappointing. The capsule tumbled from the helicopter, fouling the drogue parachute intended to pull the can in which the wing was stored away from the paraglider. Wing inflation intensified the tumbling and the emergency drogue parachute ejected too soon. When the capsule spun down past 1600 meters, the minimum recovery altitude, radio command detached the wing and allowed the capsule to descend on its emergency parachute.23
The next attempt, on 8 January 1963, after its share of delays, produced even worse results. There was no tumbling, but the storage can was late in separating; so the capsule was falling too fast when the wing started to inflate and its membrane tore. As the capsule fell below 1,600 meters, its wing not yet fully deployed, emergency recovery was ordered to no avail. The main parachute remained packaged, and the capsule crashed. Picking through the wreckage, North American  inspectors found that a squib switch in the emergency parachute's electrical system had misfired. That was not the only problem, but it was the most discouraging--the switch was a standard item, much used in the space program and not known to have failed in 30,000 successive firings. GPO warned North American to be sure everything that had gone wrong was corrected before trying again.24
A month later, North American reported to the paraglider coordination panel that five distinct failures had been spotted, studied, and fixed. The panel was convinced, but Chamberlin was not. After an extended meeting with George Jeffs, manager of the paraglider program for North American, Chamberlin decided to give the trouble plagued half-scale flight-test program another chance.25 Once again, the current crop of troubles had little impact on plans for the next phase of development, which covered the rest of flight testing, pilot training, and paraglider production. Part of Phase III, gearing up for production, was worked out and under way by 22 January. North American's proposals for the rest of the program were ready by the end of the month. GPO approved and, with the concurrence of NASA Headquarters, readied a new contract.26 But the Office of Manned Space Flight had second thoughts and stopped the procurement action "for the time being."27 The halt proved to be permanent.
The Gemini paraglider program foundered on North American's third attempt to deploy a half-scale wing in flight. Although the first two flights had been at least partial successes, the third, on 11 March, offered no comfort at all, The storage can failed to separate, so the wing could neither eject nor inflate. When the radioed command to deploy the emergency parachute produced no response, the second half-scale test vehicle joined the first as wreckage.28 Paraglider testing came to an abrupt halt.
Gemini's other major headache early in 1963, Titan II, posed a far greater threat to the program as a whole. There would still be a Project Gemini without paraglider, but not without Titan II. Despite some hopeful signs, the status of the launch vehicle remained very much in doubt. The central problem was still the lengthwise vibration, or Pogo, that bounced the vehicle while its first-stage engine was burning; but other technical problems began to compete for attention. Efforts to resolve them were coming up against a crucial disparity between Air Force and NASA goals in Titan II development.
The Martin Company's proposed answer to Pogo - a surge-suppression standpipe in the first-stage oxidizer feedline - was installed in the soon to be infamous Missile N-11, the eighth Titan II that the Air Force launched in its missile development program, on 6 December 1962. The supposed cure, far from damping the Pogo effect, raised it to +Sg, and the violent shaking induced the Stage I engines to shut down too soon.29 A rueful Robert Gilruth told his fellow members of  the Manned Space Flight Management Council that he saw one hope: "the fact that the addition of the surge chamber affected the oscillation problem may indicate that the work is being done in the right place."30
The next Titan II, launched on 19 December, carried no standpipes, but increased fuel-tank pressure, which had shown good results on some earlier flights, again reduced the Pogo level. This missile also featured oxidizer feedlines made of aluminum instead of steel, which seemed to have some bearing on the sharply lessened amplitude of oscillation. This was disconcerting, no reason for the effect being readily apparent. The Pogo problem clearly needed more study.31 In the tenth flight, on 10 January 1963, Pogo hit a new low of six-tenths the force of gravity (±0.6g) at the spot on the missile where a manned spacecraft would be located. This was getting close to the level tolerated on Mercury flights, roughly ±0.45g. But Gemini's astronauts were supposed to take a larger part than Mercury's in flying their craft into orbit. NASA's goal for the Titan II remained ±0.25g at most. Nonetheless, despite the still large gap between performance and goal, increased fuel-tank pressure had so reduced "POGO type oscillations" that Gilruth could say, "this now becomes a secondary problem."32
He may have been more concerned about another problem than he was optimistic about Pogo. Despite the low Pogo level on the tenth flight, the missile's second-stage thrust was only half what it should have been. On some earlier flights, the failure of second-stage engines to build up to full thrust had been blamed on Pogo. That now appeared doubtful. Another source of unease, and the one Gilruth now tabbed as the major problem, was the threat of unstable combustion in the second-stage engine. Static firing tests during January 1963 showed that the Aerojet-General motors might have trouble reaching a steady burn after the shock of starting.33
But this was as yet mostly surmise, and Chamberlin's concern still centered on Pogo, chiefly because he was not at all certain how far the Air Force Ballistic Systems Division (BSD), which was in charge of Titan II missile development, would go to meet Gemini's much stricter demands.34 His fears were confirmed on 29 January, when BSD's Titan Program Office froze the missile design with respect to devices for cutting vibration levels, since increased pressure in first-stage fuel tanks and aluminum oxidizer feedlines reduced Pogo below specifications for the missile air frame and systems.
This was an answer only for the missile. Tank pressures were nearing structural safety limits, and more pressure could not lower the vibrations much further, anyway. But the level was still too high for Gemini. BSD intended to keep looking for a way to achieve the lower value NASA wanted, but early in March, BSD decided that it could no longer accept the costs and risks of efforts to reduce the oscillations any further.35
 Chamberlin had no direct line to BSD, his only channel being through SSD. With BSD in charge of missile development and SSD of Gemini launch vehicles, NASA was largely a spectator. Chamberlin could do little more than appeal to SSD to intercede with BSD. Since there was no flight test program for the Gemini booster, the Titan II missile research and development program was the only chance to solve Gemini problems. But BSD was responsible for a weapon system, not a launch vehicle, and was understandably loath to risk the missile for the booster.
During March, therefore, Chamberlin spent a lot of time on the telephone, asking Richard Dineen, in charge of Gemini launch vehicle development for SSD, for help not only with Pogo but on the threatening combustion instability problem. Chamberlin hit hard on his long-standing demand for a rigorous qualification program but now stressed that qualification must be "followed by a suitable number of successful flight tests" to reach the required level of confidence in a booster for manned space flight. Me wanted to know what plans Dineen had for making sure that the Air Force test program would meet Gemini's needs, and Dineen promised a report in short order.36
Word of Titan II's troubles was slow to reach NASA's upper echelons. When James Marsh, head of the Gemini launch vehicle program at Aerospace Corporation, discussed the current status of the booster at a meeting of the newly formed Gemini Program Planning Board on 7 March, he was far from alarmist. Seamans got the impression that things were well in hand. A detailed redesign of the turbopump impellers in the first-stage engines would take care of the Pogo problem, according to Marsh, and the unstable burning in the second-stage engines was no risk to Gemini.37
 This view was rudely shattered a week later, when Seamans traveled with Secretary McNamara and a party of Defense officials to Houston for a close look at Gemini. He learned for the first time that MSC was now thinking of two unmanned flights, rather than one, cutting the number of manned missions to ten, the first delayed five months until August 1964. Trouble with Titan II was offered as the main reason for this drastic change in schedule, and combustion instability was cited as potentially a greater problem than Pogo. McNamara assured Seamans and MSC that Titan II would be fixed, but Seamans was still doubtful.38
This was only three days after the crash of the second half-scale paraglider test vehicle. The conjunction of the newly revealed impact of Titan II problems and the latest in the series of paraglider mishaps suggested that Project Gemini was in deep technical trouble. To make matters worse, Gemini had new money worries. The reprogramming effort of the last quarter of 1962 had slowed the rate at which Gemini was spending money but at the expense of stretching out the program. In the nature of things, a longer program was liable to cost more overall; when Holmes reported, early in February, that Gemini's total cost would reach $834.1 million, the figure was not too disturbing. That was about $60 million over the lowest estimate in September 1962 but well short of the $925 million that had then appeared to be a possibility.39
Just a month later, however, on B March 1963, MSC's revised preliminary budget for fiscal year 1964 reached NASA Headquarters, and it was a shock. Gemini's estimated total had shot over the billion-dollar mark. The new figures was nearly twice the cost first approved in December 1961 and almost $200 million higher than the figures Seamans and other NASA officials had been using as the basis for NASA's fiscal year 1964 budget request, most recently in House hearings earlier that week.40 So large an increase, coming on the heels of what had seemed to be a resolution of Gemini's funding problems, took NASA Headquarters by complete surprise. Chamberlin, as manager of Gemini on the field level, knew what was happening. But, waiting for an opportune moment to break the news, he was overtaken by events.
Unexplained cost increases combined with seemingly critical problems in paraglider and Titan II development to bring Chamberlin's tenure to an abrupt end.41 On 19 March, Gilruth relieved Chamberlin of his duties as project manager and assigned him to the post of Senior Engineering Advisor to the Director, cutting him off from any direct connection with Gemini. Charles Mathews took over as acting manager. He came to Gemini from the Engineering and Development Directorate, where he had recently added the job of Deputy Assistant Director to his work as Chief of the Spacecraft Technology Division. Mathews was a charter member of Space Task Group, having come  with Gilruth from Langley's Pilotless Aircraft Research Division. He had headed STG's Flight Operations Division until 17 January 1962, when he moved over to the Engineering and Development Directorate as chief of what was then called the Spacecraft Research Division.42
When Chamberlin left Gemini, an era ended. In the large and complex undertakings of modern high technology, one person can seldom be credited with so large a share in the shaping of a project as Chamberlin deserved for Gemini. Much of the ultimate success of the project had its roots in Chamberlin's brilliance as a designer and skill as an engineer, but so did some of the current harvest of troubles. The talented engineer can always see new ways to improve his machines, but the successful manager must keep his eyes on costs and schedules, even if that sometimes means settling for something good enough instead of better.
But perhaps in a deeper sense, Chamberlin can be seen as a victim of the way Gemini was created and funded. Approved as something of an afterthought in the American manned space flight program, absent  from NASA long-range budget plans, Gemini began with shaky finances. Crushing time pressure made things worse. Gemini, although in most ways just as sophisticated as Apollo, began later and had to finish its flight program much sooner than the lunar program. As Chamberlin later remarked, "we went ahead as fast as possible with whatever funding could be scrounged. . . . If Gemini were too late, there would be no need for it, and it would be canceled." In this setting, technical problems that might otherwise have appeared little more than routine assumed a more ominous guise.
Chamberlin's colleagues in and out of NASA deeply respected him as an engineer and designer but also saw his flaws as a manager and recognized the difficulties of the situation. His sudden and largely unexpected departure was thus not the blow to project morale that it might have been. The shock was also eased by the identity of the man who replaced him. Mathews was well known and widely esteemed. He took over a program that did seem to be in trouble.43
The shaky status of Gemini costs and schedules was the major factor in Chamberlin's ouster, and it was to those matters that Mathews first turned in his new role as acting program manager. An early move was a critical review of the Gemini flight program. This produced one quick decision: an unmanned mission would be flown in place of one of the manned flights; only 10 of the 12 Gemini flights were now to carry crews. This was largely a response to the stubborn problems in Titan II development. The first flight had been planned most recently as a suborbital ballistic shot to test spacecraft heat protection and validate spacecraft structure and systems. With launch vehicle status uncertain, however, this no longer seemed sufficient qualification for manned missions. Another question mark was the spacecraft itself, which did not seem likely to be ready in time.44 GPO had a new flight schedule to submit to Manned Space Flight Director Holmes by 11 April. It differed sharply in some key ways from earlier plans. The major change was that the first flight, still due in December 1963, was to be orbital, its primary objective the flight qualification of the booster. The spacecraft would serve chiefly as an instrument carrier, neither separating from the launch vehicle's second stage nor being recovered. Gemini's second flight, postponed from March to July 1964, was now what the first had been - a suborbital ballistic flight intended to prove the spacecraft could withstand high heating rates but also to qualify all launch vehicle and spacecraft systems for manned flights.
The first men to fly in Gemini now had to wait for the third mission, in October 1964, five months later than had been scheduled for  the third flight and seven months past the former date for the first manned flight. The mission was not only late, it was much reduced in scope. First planned for a full day, or 18 orbits, the mission now seemed likely to be no more than three orbits, mainly for systems evaluation.45 The three-orbit limit became official in mid-June 1963. This raised the question of what to do with the package that both of the first two manned spacecraft were supposed to carry into orbit to practice the final stages of rendezvous. Three orbits hardly seemed long enough. By the beginning of July, the rendezvous evaluation pod was cut from the first manned mission.46
The pod stayed on the fourth flight and second manned mission, scheduled for seven days in orbit during January 1965, three months after the third. This longer interval between launches was planned for the rest of the program. The two months that had been allowed no longer seemed time enough to check out machines and train crews. Another change in the flight program inserted a rendezvous mission between the two longer flights, so the fifth would be a rendezvous mission and the sixth would remain in orbit 14 days. The two long missions had been back-to-back, but this left little time to absorb the lessons of one such flight before launching another. The last six missions, each about three days long, all focused on rendezvous. The final flight was scheduled for January 1967, nearly two years after the date first approved in December 1961 and more than a year later than expected after reprogramming in late 1962. The new flight plan also reflected the uncertain status of the paraglider landing system, now scheduled only from the seventh flight on. Earlier spacecraft would rely on parachutes, and the first land landing was not expected until October 1965.47
NASA Headquarters approved the new Gemini flight plan on 29 April 1963.48 The lengthened schedule and spaced-out launches eased the pressure on Project Gemini in terms of both time and money. Technical problems and money shortages were the proximate cause of the changes, but throughout 1962 the shape of Gemini had been subtly shifting. Mercury technology proved less easy to transfer to Gemini than expected, partly for technical reasons - the planned coupling of two Mercury environmental control systems to provide for a Gemini crew, for example, went by the board as engineers tried and failed to convert the concept into detail specifications49 - but mainly because the image of Gemini had altered in the eyes of its makers. "Instead of being merely a transition between Mercury and Apollo," Gilruth told his colleagues in the Management Council on 30 April, "the Gemini program now actually involves the development of an operational spacecraft."50
Holmes spelled out what this meant in a lengthy memorandum to Seamans on 3 May. By building into Gemini the most up-to-date technology,  rather than merely modified Mercury equipment, "Gemini would have extensive and most useful applications in earth orbital space operations," even, ultimately, "as a resupply vehicle for future space stations," It would also produce a beneficial side effect: the new Gemini promised to be a much greater help to Apollo in such areas as systems development, preflight checkout, and mission training. None of this came cheaply, either in time or money, but Holmes argued it was worth it because "we have a much more valuable and worthwhile Gemini Program than could have been had if we had not taken advantage of our increased knowledge to develop and design the best spacecraft possible within the limits of our present technology."51
These were the arguments that NASA spokesmen used to explain the higher costs that Gemini had incurred in the past fiscal year and to defend their budget request for fiscal year 1964 to congressmen growing restive in the face of soaring NASA needs. Gemini, Holmes told the House Subcommittee on Manned Space Flight, was "much more than a big, overgrown Mercury."52 It had, said Webb, "what I would characterize as the potential for the first workhorse of the Western space world in very much the same way that the DC-3 airplane became a great workhorse of aviation for many, many purposes."53
How much of this was merely after-the-fact rationalization may be open to question, but whatever hopes NASA officials might have for using Gemini or helping Apollo depended on solving some urgent problems. Development of the new technology that was to transform Gemini was lagging. The most advanced spacecraft systems - propulsion, escape, and fuel cell - were running into trouble; the paraglider program had faltered; and, worst of all, the Titan II launch vehicle posed a question mark for manned space flight. Maybe Gemini would become a workhorse, and maybe that prospect was good reason to delay the flight program. But the many technical problems, Gemini's new acting manager admitted when interviewed by a leading trade journal, had already wrecked the old schedule.54
Attacking Paraglider and Titan II Problems
The most pressing worry when Mathews took charge of the project in mid-March 1963 was what to do about the trouble-plagued paraglider development program. Back-to-back failures, as North American tried to deploy the wing in flight, had destroyed both half-scale test vehicles. GPO had been funding paraglider on an interim basis since February, little money was left, and North American was ready to quit unless it got new directions. With neither time nor money enough to replace the two lost test vehicles, GPO had to work out a new test program with North American, using the hardware still on hand or almost ready - the two full-scale test vehicles slated for deployment tests,  the half-scale boilerplate left over from emergency parachute system qualification, and the paraglider trainer that North American was building.55
Spokesmen for North American and MSC met in Houston 27-28 March to discuss the options. Telephones in GPO, in the Gemini Procurement Office, and in North American were busy over the next two weeks as the main features of a revised test program were argued, talked out, and settled. The key decision was to divide the flight sequence in half and work through the problems of each phase separately before trying to demonstrate a complete flight from deployment through landing.56
Spreading the wing in flight was still the crucial problem, and it was to be tackled with the two full-scale test vehicles. The new test plan, however, was simpler than the old. As the vehicle dropped from a high-flying aircraft, its wing would inflate and deploy to convert its fall into a glide down to 3,000 meters. That ended the test sequence. Explosive charges would sever the cables that suspended the test vehicle from the wing, and the now wingless vehicle would descend to Earth beneath a large parachute. The rest of the flight sequence, gliding from 3,000 meters to a landing, was to be studied with two tow-test vehicles, modified versions of the paraglider trainer. Towed by a helicopter to the proper altitude and then released, this vehicle would be flown by a pilot down to the California desert. In the final stage of the program, Gemini static articles would be fitted with standard paraglider gear and flown through the complete flight sequence from deployment to landing.57
If everything went according to plan, the paraglider landing system could be ready for the seventh Gemini spacecraft. By the time McDonnell started building the tenth spacecraft, paraglider gear could be installed at the proper place on the production line.58
On 12 April 1963, Mathews outlined for North American what had to be done at once to put the new program into effect. The company was to stop all work on landing gear for the full-scale test vehicle, since it would now land via parachute, and to forget about trying to convert the half-scale boilerplate into a half-scale test vehicle. Instead, the boilerplate would be used as a tow-test vehicle to work out takeoff techniques needed later for manned flights. North American also had to qualify the new full-scale parachute system, which differed substantially from the emergency system - using three Mercury-type parachutes - that North American had tried hard to qualify, without much success, during the summer and fall of 1962. By the end of April 1963, North American had shifted gears and was working along the lines laid out earlier that month.59
The reoriented paraglider program was formalized in a new contract between North American and NASA on 5 May 1963 that also  closed out the earlier contracts. MSC and the contractor agreed on a year-long program (to May 1964) more tightly focused on the basic design of a workable paraglider system than the old had been, with such matters as flight training and production postponed until the design had been proved.60 NASA settled the earlier contracts with North American for $7.8 million and negotiated a $20-million price for the new effort that was intended to save paraglider landing for Gemini.61
Although doing something about paraglider was the most pressing problem Mathews faced when he took over Gemini, Titan II was the greater concern for the program as a whole. So far, Air Force efforts toward clearing up the troubles had been limited to what was needed to make its missile work. Nothing extra was yet being done to see that Titan II met Gemini's needs, although Bernard Schriever had assured Holmes that any Titan II problems that threatened Gemini would be taken care of.62 Pogo seemed to Mathews, as it had to Chamberlin, the most urgent, and Mathews, like Chamberlin, insisted that ±0.25g at the spacecraft was the highest level of vibration that NASA could accept. BSD, however, professed to be content with the g-level of ±0.6g already achieved, well below earlier levels as high as 5g. That was low enough for the missile, and BSD firmly refused to spend any more of its money to lower it further.63
GPO could do little to change BSD's stand, but Schriever, whose command embraced BSD, did have something to say about it. He ordered top officials of both BSD and SSD to his headquarters at Andrews Air Force Base in Maryland on 29 March 1963 to present a status report on Titan II problems related to its role as Gemini launch vehicle. Spokesmen for the major Titan II contractors - Martin, Aerojet, Aerospace, and Space Technology Laboratories - were on hand to discuss their efforts. What Holmes and the other NASA representatives Schriever had invited to the meeting heard was far from reassuring.
Brigadier General John L. McCoy, Director of BSD's Titan System Program Office, led off with an account of the two outstanding problems, longitudinal oscillation and combustion instability. Neither, he stressed, now threatened missile development. Trying to meet Gemini standards by changing any of the missiles still to fly in the development program was too chancy. McCoy's job was to develop a weapon system, which he objected to risking for Gemini.
The contractors argued that the problems were just about solved. Both Aerospace and Martin-Baltimore endorsed the optimistic view of Aerojet General's chief project engineer for Titan II engines, Alvin L. Feldman. Feldman pointed out that Pogo had already responded to increased fuel-tank pressure, and he saw even more promise in a combination of standpipes in the oxidizer lines and mechanical accumulators in the fuel lines. Unstable burning might be handled by modifying  the baffles on the injector that fed propellants to the engine or by starting the flow of propellants with some inert fluid.
A closed-door session limited to NASA and Air Force officials followed this open session. Here Holmes vented his frustration at the parade of numbers, statistics, and percentages on Titan II problems he had heard. The crucial point, he insisted, was that no one knew what caused either Pogo or unstable burning; without that knowledge, the booster could not be judged man-rated. Since the Air Force was now a bigger partner than before in Gemini, Holmes thought that Defense funds ought to pay a share of whatever the price might be to fit the launch vehicle to Gemini. But even if NASA had to pay the whole bill, even if Gemini had to face more delays, Holmes wanted these shortcomings corrected. Lieutenant General Howell M. Estes, Schriever's second-in-command, agreed. They decided on a joint development and test program expressly designed to bring Titan II up to Gemini standards, with Air Force Titan II money to get it started and the question of funding the rest to be referred to the Gemini Program Planning Board.64
Just three days later, on 1 April, McCoy was heading a new Titan II/Gemini Coordination Committee,* which, by 5 April, had drawn up a "Joint Titan II/Gemini Development Plan on Missile Oscillation Reduction and Engine Reliability and Improvement." It spelled out the work needed to cut Pogo levels to NASA standards and to reduce the incidence of combustion instability in the second-stage engines. It also outlined an "augmented engine improvement program" to clean up the design of the first- and second-stage engines and to enhance their reliability. McCoy's committee planned to direct the effort, with funds supplied by BSD's Titan System Program Office. The plan to improve and man-rate Titan II had two major restrictions: the weapon-system's flight test program was not to incur undue delays by waiting for Gemini items; and McCoy had the final say on if and when to fly Gemini improvements, with missile program objectives taking precedence.65
The Gemini Program Planning Board concurred in the plan a month later, on 6 May, and recommended that the Department of Defense pay for it, starting at once with current Defense emergency funds. This meant $3 million from fiscal year 1963 money and another $17 million from the next year's budget. The Air Force provided half the $3 million by the end of the month, with a firm promise for the balance.66
In acting on the Titan II plan, the board was moving beyond its charter, which called for it simply to decide what military experiments  should be carried on Gemini flights. Its roster of members, however, included Holmes and Schriever, as well as Seamans and McMillan, making it the logical group to coordinate a high-level attack on Titan II's problems. When the board submitted its recommendations to Secretary of Defense McNamara and NASA Administrator Webb on 29 May, no one was surprised that it covered not only experiments but the pursuit "with utmost urgency of" the Titan II improvement plan, using Defense funds and the missile test program.67 McNamara and Webb endorsed the board's findings. McNamara specifically agreed to pay for the program and directed the Secretary of the Air Force both to fund it and to flight-test the improvements in the missile program. In a memorandum to the board members, Webb stressed
the urgency we attach to the development of the Gemini Launch Vehicle. It is of the utmost importance that the cause of the present deficiencies in the Titan II be determined and remedial action accomplished as expeditiously as practicable . . . to eliminate the launch vehicle as a potential source of delay in the Gemini schedule.68
The delay was already more than potential, as attested by the major role Titan II problems had played in Gemini's new flight program. But further delays loomed ahead as the Titan II missile test program unexpectedly faltered during the spring of 1963 and threatened to undo the improvement plan before it had fairly begun. The 18th flight test of the Titan II missile was launched on 24 May 1963, It was only the 10th fully successful flight and the last for months to come.69
The next launch, five days later, produced a particularly disappointing failure. Martin, Aerojet, Aerospace, and Space Technology Laboratories had worked hard to confirm the hypothesis that Pogo during first-stage flight was caused by coupling between the missile structure and its propulsion system, the couple making an unstable closed loop. A study of year-old static-firing data led Sheldon Rubin of Aerospace to believe he had found the missing link in the analytic model; the partial vacuum produced by pumping caused hydraulic resonance in the fuel suction line. If valid, this finding would correct the two major shortcomings of prior analyses, which had failed to predict where oscillations ceased during flight and had wrongly predicted that oxidizer standpipes alone would suppress Pogo. Rubin's corrected model showed why Missile N-11 in December 1962 was less stable than other Titan IIs and how adding fuel accumulators as well as oxidizer standpipes would suppress Pogo. The missile launched on 29 May carried Pogo suppression devices for both oxidizer and fuel to test their combined effect. But, leaking fuel in its engine compartment, the missile burst into flame as it lifted off. Its controls damaged by the fire,  the missile pitched over and broke up 52 seconds later. In contrast to Missile N-11, the Pogo devices were absolved from any blame for the failures, but the flight ended too soon to provide any Pogo data and the problem remained unsolved.70
This setback was followed by another, on 20 June, in the 20th Titan II flight. This was purely a military test, the missile being launched from a silo at Vandenberg Air Force Base in California. First-stage flight was troublefree, with Pogo levels low enough (±.62g) to meet Air Force standards. But partial clogging of the tiny holes in the oxidizer injector of the second-stage gas generator caused thrust to fall off shortly after staging to about half the required value. The same thing had happened in two earlier tests; had the missile been carrying a spacecraft, its crew would have been forced to abort the mission.71
Back-to-back failures at this stage in the program compelled BSD to suspend Titan II flight testing. Only half the 20 flights so far launched could be called fully successful, and McCoy now faced the task of making good on at least 12 of the 13 flights still left him, to prove that Titan II was ready to join America's strategic deterrent forces. The missile had to come first, and McCoy again ordered a halt to any further attempts to lower Pogo levels as too great a risk to what remained of his test program. Although Major General Ben I. Funk, SSD commander, appealed McCoy's decision to Systems Command Headquarters, the whole question of Gemini-Titan development, and particularly of flight-testing a cure for Pogo, was once more unsettled.
A Clouded Future
In the aftermath of reprogramming, Gemini was buffeted by new crises. An offhand Defense Department bid to take over the program flustered NASA's top echelons briefly, but technical problems began taking on fearsome proportions early in 1963, with paraglider and Titan II looming as the greatest question marks. When the first months of 1963 also revealed that Gemini's money troubles had not been settled, the stage was set for a change of project managers. Charles Mathews replaced James Chamberlin as head of a faltering program. The framework was solid enough, a tribute to Chamberlin's engineering efforts, but costs, schedules, and administration were not. Mathews moved swiftly and smoothly to take these problems in hand. In short order, the status of the program was reviewed; its schedules, budgets, and objectives reassessed; and its revision outlined. By mid-1963, Gemini's managerial worries, both internal and external, had been at least temporarily resolved by a tightened organization, a lengthened schedule, and a modified program. But the major technical problems persisted and even worsened.
With many of the Gemini launch vehicle's parts still short of flight  status and with BSD firmly opposed to risking its own program to solve Gemini's problems, the prospect of meeting the December 1963 deadline for the first Gemini launch was dimming. NASA was no longer concerned simply with the status of the vehicle and the effect of specific problems like Pogo and unstable combustion on its chances of being ready in time. Although its promise had been great, Titan II's flight record was so poor that NASA was beginning to wonder whether it belonged in Project Gemini at all.72
The Darkest Hour
 The easing of Gemini's managerial problems by mid-1963 opened the way for a concerted attack on Gemini's technical problems. Even under new management, however, the last half of the year saw Project Gemini at its lowest ebb. The Gemini spacecraft, the Agena target vehicle, and, most seriously, the Titan II launch vehicle - each raised problems that threatened to overwhelm the program. This was to be Gemini's darkest hour, and it began with another dual flight that raised new fears of a Soviet victory in the race for first space rendezvous. On 14 June, Lieutenant Colonel V. F. Bykovsky orbited aboard Vostok V. Cosmonaut Valentina Tereshkova followed two days later in Vostok VI. The two passed within five kilometers of each other. Once again, however, there was a crumb of hope in the Vostok's lack of maneuvering capability. It was a faint hope.1
Titan II in Jeopardy
Gemini's biggest question mark in mid-1963 was the launch vehicle. Flight tests of the Titan II missile, suspended in June after two successive failures, had yet to produce results good enough to convince anyone that a booster derived from this missile was a safe bet for Gemini. To make matters worse, Brigadier General John McCoy, director of Titan programs for the Air Force Ballistic Systems Division (BSD), strongly opposed any changes in the missile to meet Gemini standards - and for sound reasons. He could not afford to risk the failure of the missile program for a chance to help Gemini.
 As the Titan II program faltered, NASA concerns mounted. The Gemini Program Planning Board persisted in its efforts to resolve the impasse between NASA and BSD. On 28 June, the board asked NASA to state the least it would accept for launch vehicle performance, the Air Force to describe its program in detail. Board co-chairman Robert Seamans, NASA's Associate Administrator, asked MSC Director Robert Gilruth for a precise statement of MSC standards for making Titan II over as the Gemini launch vehicle. The response, on 1 August, was a brief review of "Gemini Launch Vehicle Specifications and Requirements," which pinpointed the three major problem areas that made the Titan II unsafe for manned space flight - longitudinal oscillation (Pogo), dynamic instability of the second-stage engines, and detail design faults of Titan II engines. MSC insisted "that these problems must be satisfactorily solved and the solutions incorporated into the GLV prior to its use in the manned Gemini program."2
Every Titan II so far flown had displayed Pogo, although the level had varied, reaching a low of just over one-third the force of gravity (±0.35g) in the 17th test flight on 13 May 1963. This potential hazard to pilot safety prompted a survey of available data on human tolerance of such vibration, leading MSC to conclude that Pogo should be completely eliminated, or at least not allowed to exceed ±0.25g. A test program on the centrifuge at NASA's Ames Research Center in California, completed in July 1963, tended to confirm the validity of this stand; an MSC astronaut test program conducted immediately after the Ames tests provided even stronger support. Higher levels might be tolerable, but 0.25g still seemed a prudent upper limit. MSC preferred an experimental program to trace Pogo to its source and eliminate it but would settle for this bearable limit if proved on Titan II flights before the vehicle flew in Gemini.3
The second major problem, combustion instability, had not yet occurred in flight, but Aerojet-General's ground tests had revealed incipient instability during second-stage starting - that is, the initial engine-firing pulse could trigger uneven burning in stage-II engines. In a statistical sense, the engine was stable, since Aerojet-General could show that the instability rate was no more than two percent in ground tests. From a physical viewpoint, however, the engine had to be described as dynamically unstable, and that risk could not be accepted when human lives were at stake. Statistical reliability was not enough for a manned booster. Aerojet-General must develop and prove a dynamically stable engine before the first manned Gemini flight.4
The third major area of concern comprised a range of problems, each minor in its own right but significant in the aggregate. Of the 10 full or partial failures in the 20 Titan II test flights to date, Pogo could be blamed for only one, dynamic instability for none at all. The others resulted from small defects - a clogged injector, a failed weld, a broken line.  The central problem seemed to be "a real lack of understanding on the part of Aerojet of procedures and responsiveness to problems that must be associated with the development of engines for use in a manned launch vehicle."5
When several top-ranking MSC officials visited Aerojet's Sacramento plant in July 1963, they were dismayed at what they saw and concerned about a number of questionable practices in design, manufacturing, and quality control, in general, and several components - turbine idler gears, main fuel valves, turbine seals, and turbine manifolds - in particular. The Air Force Space Systems Division (SSD), NASA's agent for launch vehicles, had already spotted 40 engine parts that could be improved. MSC judged that most of these changes had to be made and the results confirmed in flight before the booster was committed to the first manned Gemini mission.6
The Gemini Program Planning Board heard NASA's report on launch vehicle performance standards on 5 August 1963, revised the wording slightly, and accepted it. With this statement as a basis, MSC and SSD were to arrange a formal agreement on the goals of reduced Pogo, a stable second-stage engine, and improved engines. They were also to agree on the programs needed to achieve these goals and the criteria for deciding when the goals had been met.7
Although Titan II itself was still a question mark, the managerial logjam that had so far prevented a concerted attack on its shortcomings as a manned booster now appeared to be breaking up. Major General Ben Funk, SSD Commander, told Gilruth on 8 August that Air Force Headquarters had approved the "augmented engine improvement program." Funk agreed that Aerojet's efforts left something to be desired, then outlined a series of steps he had taken to tighten up the firm's work. He had still another piece of good news. The decision to fly no more Pogo fixes on Titan flights had been reversed. The gas generator clogging problem that had marred the Titan II flight of 20 June seemed to have been solved, and the booster would soon be flying again. Missile N-25, scheduled for a September launch, would carry standpipes and accumulators to suppress Pogo.8
Aerojet-General began work on the improved engine program in September. That same month also saw a start on the Gemini Stability Improvement Program, or Gemsip, an effort to redesign the injector of the second-stage engine to overcome incipient combustion instability.9 When the Gemini Program Planning Board met again, on 6 September, MSC and SSD had agreed on the statement of "Gemini Launch Vehicle Specifications and Requirements for Major Titan II Problems" that the board had requested.10 It fully met NASA's demands. Things seemed to be moving at last.
Titan II, however, had yet to prove itself. Missile problems had already prompted NASA, earlier in 1963, to replace one of Gemini's  manned missions with a second unmanned flight. Still unsolved, they now forced NASA to plan yet another unmanned flight. On 12 July, Mathews told MSC's senior staff that GPO was thinking about backing up the first Gemini flight with an extra unmanned flight (making a total of 13 instead of 12) roughly midway between the first two scheduled missions, or about 1 April 1964. The proposed payload was a boilerplate capsule with instrumentation pallets like those in Spacecraft 1.11
At a meeting on 5 August, the Gemini Program Planning Board agreed to review the plan. The next day, Mathews wired Walter Burke at McDonnell to begin work on the adapter that would attach capsule to launch vehicle. NASA Headquarters approved the new mission and suggested calling it Gemini 1A, or GT- 1A.* Based on data from McDonnell and SSD, the project office figured the cost of the extra flight at around $2 million.12
William C. Schneider, Gemini Project Manager at NASA Headquarters, presented NASA's case for the extra flight to the planning board on 6 September. In essence, NASA wanted to guard against a failure of the first mission by planning a contingent mission, identical to GT-1, to fly before the scheduled GT-2. The board concurred, and Mathews wired Richard Dineen, SSD's Gemini launch vehicle overseer, to make sure that the second launch vehicle would be ready in time to meet the date for GT-1A. The new mission was strictly a backup, however, to be flown only if GT-1 failed to meet its objectives. The decision waited on the outcome of the first mission.13
For GT-1A, MSC diverted a boilerplate spacecraft being built for flotation tests by a local Houston contractor. Named Boilerplate 1A it arrived at the Center on 24 September, where the Technical Services Division began the task of making it flightworthy. Regular biweekly panel meetings started early the next month, and the rebuilt boilerplate was ready in mid-November. It left Houston via flatbed truck on 13 December, reaching Cape Canaveral three days later, there to have its wiring and equipment installed; the work in Houston had been limited to the structure. The adapter, built and instrumented by McDonnell, arrived at the Cape 27 January 1964. By then, however, the threat that had called forth the effort had largely dissipated, and little further work was done before GT-1A was formally canceled on 17 February.14
That cancellation reflected a striking turnaround in Titan II prospects from their lowest ebb during the summer and fall of 1963. BSD resumed the flight test program on 21 August. Although the flight itself was a success, NASA suffered another setback.  This missile was the first of five planned to carry the Gemini malfunction detection system, crucial for Gemini because it was to provide spacecraft pilots with the data they needed on existing or impending booster problems during launch. BSD had agreed to fly the system "piggyback" - installed, working, and reporting to ground receivers and recorders, but not otherwise acting on the missile. The system flown on 21 August suffered a short circuit 81 seconds after liftoff and provided no further data.15
Titan II's next launch, on 23 September, did little to dispel the gloom. A guidance malfunction threw the missile out of its planned trajectory. Since the missile was guided inertially and the Gemini booster used radio guidance, this had no direct bearing on Gemini. That was small consolation, however; Pogo reached plus or minus 0.75g, very nearly the worst since the disastrous flight of Missile N-11 in December 1962.16
The heart of the matter was foot-dragging by BSD on the question of flying Gemini fixes. Once again, the planning board took a hand. It decided to replace the agreement between MSC and SSD of 6 September with a more authoritative Memorandum of Understanding between the co-chairmen of the board, Seamans of NASA and Brockway McMillan, Under Secretary of the Air Force. The board directed NASA to submit another statement of requirements for the Gemini booster and the Air Force to provide a development plan, complete with costs and schedules, for dealing with Pogo, combustion instability, and engine improvement. The board specifically asked the Air Force for a schedule of all remaining Titan II flights, with a plan for flight-testing changes to reduce or eliminate Pogo and unstable burning.17
The meeting of the board took place on 11 October 1963. Four days later, the flight-test question was finally resolved. General Bernard Schriever, a member of the board as well as commander of Air Force Systems Command, called a meeting in Los Angeles of BSD, SSD, and Titan II contractors. Schriever himself firmly supported an active program to clean up launch vehicle problems. Of special concern was whether to follow through with plans to fly Missile N-25 with oxidizer standpipes and fuel accumulators. Aerospace, backed by Space Technology Laboratories, argued strongly for the planned flight, especially since engine ground tests begun in August had confirmed fuel-line resonance as the culprit in the failure of Missile N-11 and shown that fuel accumulators would solve the problem. They carried the day, winning the crucial decision to proceed with the test flight of N-25 as planned. Funk planned to see his BSD counterpart regularly and arranged for meetings between the two project managers, Dineen and McCoy, to make sure that there was no more backsliding.18
Later events were to prove that this time the question had, indeed, been settled.  Meanwhile, however, only the test flights could show that more determined management was the answer to the technological problems. Titan II was still in trouble, and the weekly status reports that Seamans was getting from the Air Force Systems Command after mid-September reflected a promising beginning but little more.19 Some thought was even being given to dropping Titan II from the Gemini project altogether. The Propulsion and Vehicle Engineering Laboratory of NASA's Marshall Space Flight Center began to study the desperate expedient of substituting the Saturn I launch vehicle for both Titan II and Atlas.20
Paraglider on the Wane
Work on the reoriented paraglider program of May 1963 got off to a quick start. Before the end of the month, North American Aviation was working out techniques for launching a tow-test vehicle from the ground. This preliminary effort, which involved first a car-towed half-scale vehicle and then one towed by helicopter, was designed to show what the paraglider would do during towing and liftoff and to work out proper towing techniques, all this to prepare for that part of the new test program in which a pilot would fly the test vehicle from an altitude of 3,000 meters to a landing. NASA's Flight Research Center also conducted a series of tow tests, the whole effort being completed in mid-October 1963.21
If Gemini were forced to use parachutes instead of the trouble-plagued paraglider for landing the spacecraft, the landing sites would shift from land to sea.
May 1963 also saw North American begin work on the other phase of the new test program, testing the deployment sequence with the full-scale test vehicle. Since this phase of testing called for the test vehicle to land by parachute, the first step was to qualify a parachute recovery system, one standard Gemini parachute backed up by a second. North American got off to a smooth start. Two drops of a small bomblike test vehicle on 22 May and 3 June showed that the system's two small stabilization parachutes worked. The contractor quickly began testing the full system on a boilerplate test vehicle. A minor malfunction marred the first drop on 24 June, but three good tests followed in July, with only one more needed to prove the system. What was to have been the final drop, on 30 July, brought a crucial setback. Both main and backup parachutes failed, and the boilerplate crashed.22
The company wanted to get on to the next phase of testing and argued that the failure could be safely ignored, partly because North American believed it knew how to correct the problem partly because further tests would require a new boilerplate and mean a delay in the program. The logic was sound enough, but GPO feared that, although the immediate problem might be easily corrected, its root cause - the instability of the vehicle - might produce other, and worse, problems.  GPO and North American agreed on two further drop tests. McDonnell furnished the new boilerplate, which North American, on the basis of spin-tunnel tests, modified to provide a more stable suspension system. That took time; over three months elapsed before the next drop, on 12 November 1963. Everything worked, and another test three weeks later confirmed the result; the parachute recovery system was at last qualified for full-scale vehicle deployment tests.23
Proving the parachute system was not the only source of delay. Design engineering inspections of the full-scale test vehicle on 1 August and the tow-test vehicle on 27 September produced the normal share of required changes. Wind tunnel tests of North American's first full-scale prototype wing at Ames Research Center in October yielded too little data and had to be repeated in early December. So it was late November before the contractor could deliver the first tow-test vehicle to Edwards Air Force Base to begin its manned program and mid-December before the two full-scale vehicles arrived.24 With almost two thirds of the time available under the new contract exhausted, North American had yet to begin the major flight-testing portion of the program.
By the fall of 1963, the status of paraglider in Gemini was once more in jeopardy only partly because of North American's troubles. The inflated frame used in the paraglider design was being challenged by advocates of what seemed to be a viable alternative - an all-flexible gliding parachute, the so-called parasail. This device offered a lift-to-drag ratio ranging from 0.9 to 1.2, lower than paraglider's but still enough to provide worthwhile range and control. It was further handicapped by its relatively high rate of descent, which required landing rockets to cushion impact with the ground. But, overall, parasails matched conventional parachutes closely enough to promise a reasonably quick and relative cheap development of a reliable device for land landing.
The gliding parachute had, in fact, competed with the inflated-frame paraglider design back in 1961, when the choice of a land-landing technique for what was then the Mercury Mark II project was being made. Although rejected for Mark II, the concept persisted as the subject of a modest research and development program at MSC.25 As paraglider faltered, parasail seemed more attractive. Project Gemini's new manager, Charles Mathews, was more receptive to parasail - or less committed to paraglider - than James Chamberlin had been. Supported by MSC Director Gilruth, Mathews called on GPO for another look at parasail. In April 1963, after the second half-scale test vehicle had crashed but before the future of the paraglider program was decided, he asked McDonnell to study changing Gemini's landing system from paraglider to parasail.26
While McDonnell pursued its study, MSC's Flight Operations Division  and Systems Evaluation Division continued testing a parasail system and pressing for its adoption. Paraglider still had highly vocal backers, however, who denied that its problems involved anything more than sequential details that would have to be ironed out for any recovery device, even conventional parachutes. Claiming that paraglider development had been known from the first to be a hard task, they objected to dropping it after so much of the work had already been done.27 The lines were drawn here they had been in 1961: Flight Operations Division and the Engineering and Development Directorate still opposed paraglider; most of the project office and the prospective pilots, supported by Flight Crew Operations, favored it.
When McDonnell finished its study early in September 1963, the issue was carried to NASA Headquarters. The company's informed guess at the cost of a parasail and landing-rocket system for the Gemini spacecraft was $15.7 million, with a good chance to be ready for Spacecraft 7. When the parasail proposal was informally presented to NASA Headquarters on 6 September, it was rejected. Dropping paraglider on the verge of flight testing, leaving nothing to show for all the time, money, and effort already spent, was out of the question. The alternative, going ahead with parasail development as something to fall back on if paraglider failed, was ruled out for lack of funds to support both tasks at once.28
Although reprieved, the paraglider program did not come through unscathed. High-level talks between MSC and NASA Headquarters produced still another reorientation of the program.* The paraglider landing system program was stripped of all other objectives, leaving as its only goal proving paraglider's technical feasibility - which meant primarily showing that the wing could be inflated and deployed in flight to achieve a stable glide - with the accent on staying within the $16.1 million budgeted for fiscal year 1964. Until that goal had been met, there was to be no further work on a prototype system for Gemini, much less on production. Gilruth insisted on a clear understanding that paraglider might still fly on Gemini if the flight tests succeeded, that paraglider's future in Gemini had not been foreclosed.29 The implication of foreclosure was nonetheless there.
Under orders from MSC, North American ceased its efforts to keep the full-scale test vehicle fitted with the latest Gemini equipment. MSC also directed McDonnell to stop all testing related to installing the paraglider, to design parachute versions of all Gemini spacecraft, and to plan on putting paraglider in the last three, the last two, or  only the last spacecraft. Nothing of paraglider was to remain in the spacecraft except the option to put everything back if the flight testing succeeded. Parachutes had, by late 1963, displaced paragliders as the planned means of recovery through the ninth mission. Paraglider landing was still listed for the last three Gemini flights, but some planners, SSD Commander Ben Funk among them, assumed paraglider would not be included in the tenth mission, either, "and probably will not be carried on any of the twelve flights."30 The very fact of paraglider's doubtful status had already begun to close off any real chance to fly in Gemini, whether it proved itself or not.
A common feature of spacecraft development, and always a matter of concern, seems to be an innate tendency toward weight growth. Gemini was no exception. A complete paraglider landing system weighed almost 360 kilograms more than a conventional parachute recovery system. Once paraglider's place had been questioned, that difference was seen as a bonus and was simply used up. Experiments, for instance, began to encroach on as yet unfilled space allotted to paraglider, especially after January 1964, when the Manned Space Flight Experiments Board was formed. Gemini's planners were beginning to look on paraglider as an extra demand on the payload budget, already pushing the limits set by the booster. If paraglider were to be restored, some other mission objectives would have to give way.31 In other words, even if North American succeeded in showing that paraglider worked, that could no longer guarantee an attempt to fly the system in Gemini. Everything rested on the outcome of North American's upcoming effort to deploy the wing on the full-scale test vehicle in flight; although success could not ensure a place for paraglider, failure would surely bar it.
Spacecraft Systems Become More Troublesome
Work on the systems that made up the Gemini spacecraft was moving along well in early 1963. Design had largely been completed, and developmental tests were starting.32 In some instances, this revealed unexpectedly hard problems. Three systems, in particular - fuel cell, propulsion, and escape - began to emerge as potentially critical areas. As a group, these systems called for the largest advance beyond existing technology. Each was essential to a major Gemini objective, each was new to the manned space flight program, and each resisted efforts to resolve its problems.
The Gemini fuel cell that supplied electrical power to the spacecraft consisted of three stacks connected to form a battery section. Each stack was made up of 32 cells between the end plates. This is a sketch of a fuel cell stack and its location in the spacecraft adapter section.
A major innovation in the Gemini spacecraft was the substitution of fuel cells for conventional batteries as the prime source of electrical power during flight. McDonnell had subcontracted the development of this system to General Electric (GE). By the end of 1962,  GE had completed facilities at its Direct Energy Conversion Operation in West Lynn, Massachusetts, to produce fuel cells. GE had also surmounted the first serious development problem: leakage of oxygen through the cell's ion-exchange membrane, which proved to be largely the result of mechanically induced stresses rather than an inherent design weakness.33
A schematic of the principle of its operation.
Solving this problem, however, exposed another. With leakage controlled, fuel-cell test units working over longer times showed degraded performance. The cause appeared to be contamination of the membrane by metal ions from the fiber glass wicks that removed water produced by the operation of the cell. Leaks in the tubes that fed hydrogen to the cell were a second source of test failures. Both problems demanded design changes. Dacron cloth replaced fiber glass wicks, and a titanium-palladium alloy supplanted pure titanium tubing, which had proved susceptible to cracking. Slow delivery of both materials, as well as the necessary redesign, began to affect schedules. Dacron produced its own problems: the new wicks touched the membrane, drew off electrolyte, and impaired cell function. Thinner wicks were an easy answer.34
The test failures, design changes, and revised production techniques combined to delay the fuel-cell program. GPO began looking for ways to increase the rate of fuel-cell production and to install fuel cells at a later point in spacecraft assembly. A visit to GE in May 1963 convinced both GPO and McDonnell that the current program was unrealistic; schedules allowed too little time for testing and failed to provide for contingencies or troubleshooting.35 Throughout the spring and summer of 1963, McDonnell and GE kept juggling test and production units, trying to meet ever less tenable schedules, as slippage in the fuel-cell program mounted.36 These efforts were complicated by further development problems.
The project office was far from certain that fuel cells would be ready on schedule, even when GE began shifting its main effort from engineering and development to making fuel-cell stacks on the production line.37 On 27 August 1963, GPO asked McDonnell for an engineering evaluation of batteries for electrical power in Spacecraft 3, the first man-carrying ship, scheduled for October 1964; the fuel cells were to remain aboard to be used only on a test load for purposes of flight qualification. When and if proper operation was confirmed, they might then be hooked into the spacecraft main electrical system. McDonnell had a plan for dual installation of batteries and fuel cells ready within a month.38 Mathews then requested a design study of substituting batteries for fuel cells in all seven spacecraft planned for two-day rendezvous missions.39
NASA Headquarters also took action.  George E. Mueller, NASA's new Deputy Associate Administrator for Manned Space Flight, arranged for three senior engineers from Bell Telephone Laboratories* to visit the GE plant to assess the status of the fuel-cell program.40 Rumors were already circulating that fuel-cell problems might force NASA to limit all Gemini missions to two days.41 GE experiments had shown that Gemini fuel cells had an operating life of 600 hours in theory, but a number of factors, among them the high operating temperatures imposed by a newly redesigned cooling system, had reduced that figure to less than 200 hours in practice.42 Fuel-cell problems were never conceptual. As a source of electrical power for long-term orbital missions, no one doubted that cells had a solid edge over batteries. The rub came in trying to convert that concept into hardware to meet Gemini specifications - essentially a matter of nuts and bolts, compounded to some extent by managerial shortcomings. This was clearly pointed up in the findings of the Bell experts, who toured the GE plant on 29-30 October 1963.
Their key tasks were to spot the development problems that remained and to answer two questions: Could GE solve these problems? What were the contractor's prospects of meeting Gemini production schedules? The team pinpointed technical matters of fuel-cell structures, materials, and the like, as exemplified by uneven current distribution because of poor contact between membrane and catalyst or catalyst and rib. The Bell engineers thought that GE could solve these problems, given enough time. Whether there was time, however, was something else; the team suggested that NASA might want to think about a backup program. GE was already six months late. Despite its stated intent to make up the lost time, GE would be doing well to maintain the current schedule. The Bell recommendations, like those put forward a little later by McDonnell in a survey of possible fuel-cell changes to meet Gemini operational needs, were restricted to narrow technical considerations.43
Fuel-cell production came to a halt on 26 November, as two GE task groups tried to resolve persistent engineering and manufacturing problems. Testing of the stacks on hand continued, but GE could build no new ones until a thorough study had revealed the causes of poor fuel-cell performance.44
Still fearing that fuel cells might not be ready for Spacecraft 3, Mathews instructed Walter Burke to alter the spacecraft's electrical system to accept either batteries or fuel cells as power sources when the spacecraft reached Cape Canaveral. By mid-December, convinced that the fuel-cell system could not be qualified in time, GPO opted to fly  the first manned mission with batteries. But Spacecraft 2 would be fitted with both systems, chiefly to afford a chance to qualify the fuel-cell reactant system. The reactant supply system was a distinct development. The system, subcontracted to AiResearch, stored and fed to the cells the hydrogen and oxygen they ran on.45
There was still little reason to believe that fuel-cell problems could be resolved even for later Gemini flights. On 20 January 1964, Mathews asked Burke to begin work on a battery-operated system for Spacecraft 4. Switching from fuel-cell to battery power for these two spacecraft cost Project Gemini almost $600,000.46 The GE task groups having completed their intensive six-week search for the causes of the problems, a meeting was scheduled in Houston on 27 January 1964, between NASA and its contractors to review fuel-cell status and to decide what to do about it.47
Although some missions might have to be curtailed, the Gemini spacecraft could carry men aloft without fuel cells by using conventional batteries. No such easy answer existed for the escape system. Any effort to replace it with something else would not only be difficult but far more costly. In the spring of 1963, some thought the change would be worth whatever it cost. MSC's Flight Operations Division revived a proposal to replace ejection seats with an escape tower, the system used in Project Mercury. Doubtful that the seat could be qualified in time and skeptical of its value as an escape device in any case, chief of Flight Operations Christopher Kraft urged Gilruth to start a backup program to see, at least, if an escape tower could be used for Gemini.48
Gemini Project Office, seconded by the astronauts and Flight Crew Operations, still believed that Gemini ejection seats could be made to work. Hard-to-solve problems were only to be expected in the development of so advanced a system.49 Things were, in fact, starting to look up. Simulated off-the-pad ejection (Sope) tests had been suspended in the fall of 1962 until all system components were ready and the complete escape sequence, including recovery of dummy astronauts, could be demonstrated. The system had also grown more complex; it now included a device - a hybrid of BALLoon and parachUTE called a ballute - to prevent an astronaut from spinning during free fall if he had to eject from an altitude much higher than the 2,000 meters at which his personal parachute was set to deploy.50
When Sope testing resumed on 7 February 1963, the results were disappointing from the standpoint of proving the complete escape sequence - the ballutes failed to inflate and release and the personal parachute did not deploy properly. But, in the view of Kenneth Hecht and his colleagues in GPO who were in charge of escape-system development, the test marked a real breakthrough. They had been convinced that the key problem was dynamic, the relationship between rocket-motor thrust vector and the shifting center of gravity of the seat-man combination.  Analysis of the data from the test revealed that they had been overlooking a significant factor in their calculations - the tendency of the ejecting mass to tip as a result of its inertia when it left the end of the guide rails. With that factor accounted for, the key problem was solved. "The remaining technical problems," Hecht later recalled, "were in debugging the details of a very complex design."51
That, however, was no small order. Measures were taken to ensure that the personal parachute would deploy at the low dynamic pressure associated with off-the-pad aborts. McDonnell and Weber engineers also cleaned up the makeshift additions to seat design that had piled up in the course of development. But the complete escape sequence still had to be proved. All that took time. The new package was given its final checkout on 22 April 1963.52 Three weeks later, on 15 May, Sope testing was under way again, with heartening results.  The last four tests in the series of 12, which had begun in July 1962, were almost flawless, only an insignificant failure of part of the test gear marring the final test, on 16 July. The development phase of pad ejection testing was now complete.53
Still unfinished, however - indeed, scarcely begun - was a second series of development tests, sled-ejection tests. These were not so novel as the Sope tests, being in common use for all ejection-seat development. They simulated ejection at high dynamic pressures - as might be met in an escape during first-stage booster firing. In the Gemini tests, conducted at the Naval Ordnance Test Station in California, two ejection seats were mounted side by side in a boilerplate spacecraft carried on a rocket-propelled sled running on tracks. Known as the Supersonic Naval Ordnance Research Track, it was, obviously, called "Snort." But the delays met in Sope tests, compounded by the reprogramming of late 1962, slowed the sled program.54
This may have been just as well, because the test vehicle was badly damaged in its first run, on 9 November 1962. This was not an ejection-seat test. The test station needed a trial run to confirm its data on sled performance and structural soundness. It got what it wanted, but a rocket motor broke loose and smashed into the boilerplate, starting a fire. Although both boilerplate and sled needed a lot of work, GPO foresaw no delay in the sled-test program itself, since other factors had already required it to be rescheduled, leaving ample time for repairs.55
Flawless Sope tests on 15 and 25 May 1963 showed that the new seat design was working and sled tests could begin. A dynamic dual ejection on 20 June was a success, followed by a second good run on 9 August. That turned out to be the last test in 1963. The seat system went through still another redesign, this time to provide for the automatic jettison of backboard and egress kits.56 A more serious problem, and one that persisted, had little to do with the system itself. Testing was continuously hampered by shortages and slow delivery of parts, particularly the pyrotechnic devices that were crucial to so many of the system's functions.** 57
Although fuel-cell and escape systems had begun to look troublesome in 1962, the thrusters on which the Gemini spacecraft relied for attitude control and maneuvering in orbit and for control during reentry seemed at first to present no special problems.  The subcontractor for both these systems, Rocketdyne Division of North American, focused its research effort on developing an engine of 111 newtons (25 pounds of thrust) able to perform within specification for five minutes of constant burning. McDonnell and Rocketdyne engineers assumed that a thruster design able to meet that standard could also sustain the pulsed, or cyclic, firing that would be called for in practice. They also thought that a working, 111-newton-thruster design need only be scaled up to meet the performance demanded of the 445-newton (100 pound-thrust) maneuvering thrusters. They were wrong on both counts.58
The schematic shows the arrangement of the thrusters on the Gemini spacecraft; the inset shows a cutaway of a thruster.
Then Rocketdyne began running into trouble in steady-state thruster firing. Early tests of the small thrusters showed they tended to char through their casings and to fall off sharply in performance within little more than a minute of continuous firing. When this problem was fixed early in 1963 by a makeshift strengthening of the throat region of the thruster, which allowed it to attain a full five minutes of firing and more, Chamberlin was cautiously optimistic about having qualified units ready to be installed on time.59
The maneuvers possible with various thruster combinations.
That hope suffered a setback when Rocketdyne turned to pulse testing and found that pulsing thrusters burned out their ablative liners far more quickly than identical thrusters firing continuously. Char rates - the speed with which thrust-chamber liners burn up - were one and one half times greater in pulsed firing, and thrusters were failing as their lining material was exhausted and their casings burned through. Such expedients as oxidizer to fuel ratio lowered (from 2.05:1 to 1.3:1) to reduce chamber temperatures and thus char rates, thickened ablative linings, and shortened firing times (for some thrusters) could only alleviate, not solve, the problem. In May 1963, Rocketdyne had neither completed the design of the reentry control thrusters nor fired the attitude thruster through a full pulsed duty cycle. The company had fallen three months behind schedule in delivering the thrusters and other parts of the system to McDonnell for Spacecraft 3, and development testing was equally laggard.
To make matters worse, new tests revealed that the larger maneuvering thrusters could not be simply enlarged versions of the attitude engines. Rocketdyne had, so far, done very little work on the maneuver thrusters, partly because of its focus on the smaller model and partly because it had been slow to provide test hardware and facilities. During April 1963, testing of the larger OAMS thrusters had ceased altogether. The new findings now compelled the company to reactivate that test program at once.60
Rocketdyne made one design change after another in an effort to put together a thruster that worked, with no striking success. By July 1963, McDonnell was willing to accept a version of the attitude thruster that could not be ready until Spacecraft 5.  Relaxed test requirements and less stringent performance standards - lower oxidizer to fuel ratios, shorter firing times, and reduced thrust ratings and specific impulse for all engines - helped a little, but grounds for real optimism were slight.61 As the summer of 1963 drew to a close, no small OAMS thruster had achieved a full mission duty cycle. A few larger OAMS thrusters had, but too few to be sure and with too small a margin of life beyond the duty cycle. The reentry control thrusters looked a little better, largely because of the lesser demands placed on them. They had to function only for a relatively brief time during reentry and could be expected to run dry before burning through.62
Even the reentry thrusters, however, hardly inspired confidence. Stabilizing the spacecraft at subsonic speeds during the last phase of reentry, from roughly 15,000 to 3,000 meters, had been intended as one function of these motors. (The other, and more important, was to hold the spacecraft in the correct attitude for retrofire to control the angle of reentry and thus to prevent either too steep or too shallow a flight back into Earth's atmosphere.) But, in September 1963, GPO decided that the thruster problems were severe enough to warrant seeking another way to steady the spacecraft. Since the first six Gemini spacecraft were then slated for parachute recovery, GPO decided to add a drogue parachute to the system for this purpose. Development testing of the parachute recovery system had finished in February, and qualification testing was well advanced. Mathews ordered a halt to these tests on 3 September and directed McDonnell to add the drogue.  The first hope, that the new system could be ready for Spacecraft 2, did not survive a close look at the effort required. It was slated instead for Spacecraft 3, the first manned spacecraft; Spacecraft 2 would fly with the non-drogue version.63
Rocketdyne, still struggling to meet the 232.5 seconds of pulse operation required of the small attitude thrusters and the 288.5 seconds demanded on the larger maneuvering thrusters, received a jolt in October 1963 from a McDonnell warning that thruster life would have to be doubled or tripled. Astronauts flying simulated missions used the thrusters even more strenuously than they were designed for, and there seemed to be no choice but to widen the margin of performance. Several months elapsed before the new demands were settled at 557 seconds of pulse operation for the small thrusters and 757 seconds for the larger ones. In the meantime, however, thruster testing at Rocketdyne ground to a halt, and the program threatened to founder. No end to development testing was yet in sight, and the start of qualification testing was a long way off. During November and December, Rocketdyne undertook an intense study of the basic features of small ablative rocket engines; McDonnell began work on an alternative design, cooled by radiation rather than ablation; and GPO was thinking seriously about the drastic step of starting qualification tests before development tests were completed.64
A New Headache
Despite its key role in Gemini, the Agena target vehicle had received far less attention from GPO during 1962 and early 1963 than other parts of the program, chiefly because time seemed more than ample. Since it was not scheduled into the flight program until the fifth mission, Agena started with seven months more lead time than the spacecraft and Titan II, and that margin more than doubled as a result of the reprogramming crisis of late 1962 and the revised flight schedule of April 1963. By the spring of 1963, although still slated for the fifth mission, Agena's maiden flight was not expected until April 1965, 13 months later than originally planned and trailing the first Gemini mission by almost a year and a half.65
That was just as well, because Agena development had moved very slowly. Agena's two propulsion systems, primary and secondary, were subcontracted to Bell Aerosystems Company in Buffalo, New York. The primary system was built around the Bell Model 8247 engine, into which were pumped storable, hypergolic propellants: unsymmetrical dimethyl hydrazine as fuel, inhibited red fuming nitric acid as oxidizer. Its rated thrust was 71,000 newtons (16,000 pounds), and it helped push Agena into orbit (the main boost coming from the Atlas launch vehicle) as well as powering later orbital changes.
 The major change in the new engine from the standard model on which it was based was in the starting system. Solid-propellant charges, or "starter cans," in the standard model fed high-speed gas to start the turbine which pumped propellants to the engine. Since these cans could not be reused, the number of times the engine could be restarted was limited by the supply of extra starter cans that could be carried. Gemini required an engine that could start at least five times, and Bell proposed to meet this demand by switching to a liquid propellant starting system. Liquids were stored in rechargeable pressurized tanks, which fed them to a gas generator where they were converted to gas and transmitted to the turbine. MSC approved the change in September 1962.66
Like the primary system, the secondary propulsion system was a modification of a system already in use. Several Agenas had carried an auxiliary propulsion system to permit small adjustments of orbits. Two major changes set off the new model, 8250, from the former system: the new secondary propulsion system was modularized instead of having its parts scattered at various sites in the vehicle, and stainless steel bellows were used in place of Teflon bladders to expel propellants from their storage tanks. The Gemini-Agena secondary system comprised two identical modules, separately mounted but fired in unison. Each module was self-contained, with propellants, pressurized nitrogen to operate the bellows, controls, plumbing, and two thrusters. The larger of the two thrusters, rated at 890 newtons (200 pounds), was intended chiefly for minor orbital adjustments, and the smaller 71-newton (16-pound) thruster for orienting the Agena just before the primary propulsion system fired. MSC had approved the modified secondary propulsion system in August 1962.67
Bell had just started its test program when, in the fall of 1962, Gemini's budget crisis struck. While Agena's role in Gemini was under fire, development stopped. But when the smoke lifted, Agena was still very much a part of the program. Contract negotiations between SSD, as NASA's agent, and Lockheed Missiles & Space Company, the prime contractor, began in January 1963.68 Testing of Agena propulsion systems could now begin. When it did, Gemini confronted a major new problem area.
By April 1963, Bell had completed a development version of the primary propulsion system, test-fired it, and shipped it to the Arnold Engineering Development Center (an Air Force test facility in Tullahoma, Tennessee) for a series of tests to prove that the engine would restart at the pressures and temperatures it would meet in Earth orbit. Tests began on 3 May and continued over the next two months with few surprises, although two problems did emerge. One involved the turbine, which tended to spin too fast. The other trouble spot was the  latch-type gas generator valve that controlled the flow of propellants from the start tanks to the gas generator. These valves sometimes opened when they should have stayed closed, failed to open on command, or stuck open. SSD reported to MSC's Atlas/Agena panel that both problems were being closely studied.69
Bad luck rocked the program on 15 July, however, when the two problems combined. The valve failed during a test, calling for an emergency shutdown of the engine. A mistake in the choice of shutdown procedures spun the turbine out of control and destroyed the turbopump assembly. That was the end of testing at Tullahoma. Bell planned to finish the series in its own plant in Buffalo, once the problems had been corrected.
The turbine was fairly easy to fix by adding an electronic circuit to monitor its speed and shut it down automatically if it started spinning too fast.70 But the gas generator valve was not so simply fixed. The failure on 15 July was not its first. A new design was clearly called for. Bell set out to improve its latch-type valve, but how good even an improved version could be was a real question. Bell also went to work on an alternative design, solenoid operated rather than latch-type. Tests over the next few months lent weight to the view that a solenoid valve was not only inherently more reliable but also reduced the complexity of the engine as a whole.71
These advantages, and the still unanswered questions about the latch-type valve, swayed a meeting at the Bell plant on 15 November. The participants decided to switch to solenoid gas generator valves in the Gemini-Agena primary propulsion system and forget about latch-type valves. But development had been much delayed. Preliminary flight-rating tests had been scheduled to begin in September. Switching to the new valves would cost four months and postpone the start of these tests until January 1964.72
Problems and delays also cost money. Negotiations in January and February of 1963 had set the price (including Bell's fee) of primary system development at $4,771,030. The price tag for solving the turbine problem would be about $300,000. Total costs kept going up, especially after the valve design proved hard to resolve. Toward the end of August, the money actually being spent began to exceed that predicted. By late October, Bell's guess at the cost of completing the program had climbed to $6.177 million, which Lockheed thought was at least $300,000 too low.73
Agena's secondary propulsion system developed along the same lines. The new stainless steel bellows produced delays and rising costs. Negotiated cost and fee was $4,395,811; by the time that figure was settled in May, Bell was already asking for an additional $500,000 for the bellows. Scarcely a month later, actual spending was passing predicted  expenses as bellows and tanks required still further design work and more testing. In mid-October, Bell's best estimate for the secondary system was $4.63 million, while Lockheed forecast $5.2 million.74
Growing engine costs were only part of a trend that brought the Gemini-Agena program to another critical pass in the late summer and fall of 1963. Other program costs were also rising, and the comfortable schedule cushion with which Agena had emerged in the revised program of April had eroded. Shortly before NASA Headquarters sanctioned the revised program, Lockheed estimated the cost for its work at roughly $50.4 million, with $17 million needed for fiscal year 1964.75 After meetings in May and June to settle details of the new schedule, Lockheed reported its projected total cost as $53.285 million, but SSD had set its sights even higher. NASA's Air Force agents wanted $37.2 million in fiscal-year 1964 funds for Atlas-Agena, with $26 million of that earmarked for Lockheed's Agena contract. GPO protested. Mathews thought that was too much money in view of the stretched-out schedule and wondered if the program could be completed at any reasonable cost with money being spent at that rate. He warned SSD that such spending could not be allowed.76 When SSD replied on 10 September 1963, current demands were down but the price of the total program was up again, to $57.46 million for Agena and $103.555 million for the entire Atlas-Agena program.77
As costs rose, schedules slipped. One source of delay was attempted improvements. The first Agena D programmed for Gemini was AD-13. Meanwhile, however, the Air Force had started a program to improve the standard Agena, the first of which was to be the AD-62 model. The improved version, unlike the earlier model, came equipped with Bell's 8247 engine, which Gemini needed anyway. Since there seemed plenty of time, Lockheed's contract was amended to replace AD-13 with AD-62 as the first Agena for Gemini, at a cost of two months. Another month or more vanished when the Air Force decided to put the restartable Bell engine in AD-71, rather than AD-62, and GPO agreed to take that one. Work on test facilities at Lockheed was slower than expected, adding to the slippage, and development problems in the propulsion systems threatened to delay the program still further.78
The Gemini Project Office was less than happy with the course of events, its manager least of all. Mathews was concerned about rising costs, of course, but he was just as concerned with the dearth of information that was reaching him through the filter of SSD. With the Air Force running the Gemini-Agena development program for NASA, Mathews could only plead with his agent to exert more control. Not only was GPO being bypassed in the process that approved changes Lockheed wanted to make, but the project office was not always even told what these changes were. Mathews observed, with good reason,  that such decisions as switching from AD-13 to AD-62 (and later AD-71) for the first Gemini-Agena were bound to cause program delays. He urged SSD to think twice about any further changes "considering the deleterious effects that improvements can have."79
SSD, however, was not really much better informed than GPO about Lockheed's changes. Mathews' protests about the lax and shallow control SSD imposed on Lockheed highlighted the gulf that divided NASA from the Air Force on the administration of government contracts. The Air Force preferred to accept Lockheed's record in filling past contracts as proof of its competence. The government was, in essence, paying for Lockheed's expertise. Pressing for too many details of funding technology might hinder progress, cutting into the contractor's flexibility without adding much to its prospects for doing the work. To the Air Force, NASA's demands for detailed technical and financial data seemed at best superfluous, at worst harmful. What NASA wanted, of course, was real control of the program, and that demanded precise and thorough information. Lockheed was merely a case in point. The conflict between NASA and the Air Force over how tight a rein the government needed to exercise spanned the whole range of contract management. For NASA, it was a basic and never-ending problem.80
In an effort to bring the Gemini-Agena program into line, Mathews dusted off and sent to Charles Wurster, SSD's chief of Gemini-Agena engineering, a formal statement of work that dated back to July 1963. Such a document was needed, in any case, since there had been no formal work statement since Marshall Space Flight Center had left the picture. The new statement diverged most sharply from the old in the stress it laid on schedules and management. GPO insisted on tight control of all contractors, chiefly by using the system of coordination panels to keep close watch on what was going on. GPO also wanted the last word on any changes, with none to be approved until that office was satisfied that it had every piece of relevant data. So widely did NASA and Air Force viewpoints diverge that it was 18 months and 15 versions of the work statement later, in March 1965, before MSC and SSD finally agreed.81
NASA also planned to bring the Aerospace Corporation into the target vehicle program in a role analogous to that it already held in the launch vehicle program, general systems engineering and technical direction. The official end of Mercury in June 1963 had freed a number of experienced engineers for other work. Wurster suggested, and Mathews agreed, that Aerospace had something to contribute to Gemini Atlas-Agena program, especially in view of the work it had done with Mercury's Atlas launch vehicle. Also in favor of the plan was a chance to impose a degree of technical continuity via Aerospace across all phases of Gemini being carried out under Air Force contracts.82
 Even if these measures worked, however, they would take time to show any effect. In the meantime, the Gemini Atlas-Agena program was in trouble, with engine development lagging badly, funding and schedules still changing for the worse without much warning. By the end of 1963, most of the time that had seemed so ample in the aftermath of the revised Gemini flight program just eight months before had vanished. The schedule for completing Agena development and for building the first target vehicle now had no slack, and any further problems threatened to delay the first rendezvous launch.83
The last half of 1963 witnessed Project Gemini beset by technical problems that stubbornly resisted solution. No major Gemini system - whether launch vehicle, paraglider, spacecraft, or target vehicle - could confidently be judged ready to fly. These months, in which the approved Project Development Plan of December 1961 had scheduled Gemini's first four flights, became instead a time of troubles; even the revised schedule of April 1963, which called for a first flight before the end of that year, proved beyond reach. And as if to underscore those troubles, the Soviet Union showed that it still held the lead in the space race; 1 November 1963 saw the launch of Polet I, a new spacecraft planned "for use in manned orbital rendezvous flight." Although unmanned, it "described complex figures in space" that shifted its first nearly circular orbit to a highly elliptical 1,437- by 343-kilometer orbit.84
Yet, throughout these months that seem so trying in retrospect, the enthusiastic engineers and technicians, both in government and industry, sustained optimism that transcended the hard facts.85 Part of that optimism might be chalked up to experience. The pattern of rising costs, sagging schedules, and tough problems was a familiar one at the cutting edge of aerospace technology. Then, too, although the precise nature of Gemini's problems could not have been predicted, they did arise where they were expected - in those systems that demanded the greatest advances beyond current technology. That the escape system, for example, should be hard to develop and qualify scarcely came as a surprise. It had to meet standards far more stringent than had ever been imposed on ejection seats before, and the general nature of the problems to be met could be, and were, foreseen.86
Initial schedules and cost estimates tend to be based on the most optimistic assumptions, the completely troublefree development of many complex systems. And these estimates depend on guesswork when new technology is involved - informed and reasoned, to be sure, but guesswork nonetheless. Rightly or wrongly, an organization like NASA assumes that Congress, the source of the money to make things go,  prefers fast, cheap programs: the shorter the time and the lower the price, the better a program's chances for support. But there is another, perhaps more weighty, reason for planning optimistically. If time and money are provided for contingencies, then they tend to be used simply because they are there. On the other hand, starting with the strictest limits and yielding further increments of time and money grudgingly may well produce the optimum achievement of the desired goal.87 In reality, most of Gemini's troubles in 1963 and later were the product of careful planning and design, credited to the program's first manager, James Chamberlin, that got the project off to such a quick and promising start. This auspicious beginning encouraged NASA to move toward a more ambitious program, to push Gemini closer to its design limits. Problems that might have looked only mildly worrisome in the context of the original Gemini concept took on a more threatening guise when the margin for error had been much reduced.
For a variety of reasons, then, Gemini workers were more confident than a backward look at the difficulties may seem to warrant. But the problems were real; and their gravity should not be downgraded even though, in almost every instance, they responded finally to efforts to resolve them.
 The faith that sustained Project Gemini's managers and workers through the dark days of 1963 was not misplaced. Even before the year was over, some of the hardest problems had begun to yield. Gemini's prospects were far brighter by the spring of 1964 than they had been in the fall of 1963. There was still much work to be done, and not every effort at problem-solving was crowned with success. The project that stood on the verge of proving itself in the spring of 1964 was not the same project that had begun two years and more before, nor even the same project that emerged from the budget and managerial crises of late 1962 and early 1963. But most of what its founders had set out to prove had survived, and what had been lost could be balanced with what had been gained.
On 1 November 1963, "Program" replaced "Project" in the title of the office that directed Gemini. This change reflected its responsibility for the program as a whole, and not merely for the spacecraft. Since that had been true from the outset, the new name did no more than underwrite a reality that already existed. MSC Director Robert Gilruth announced it as part of a major reorganization designed to strengthen both Gemini and Apollo now that Mercury was over.*  Mercury's manager, Kenneth Kleinknecht, joined Gemini as deputy manager under Charles Mathews. Kleinknecht brought with him about a third of his former staff.1
On the same day, 1 November 1963, an important realignment of NASA Headquarters also went into effect, and for much the same reason: Project Mercury's demise was a chance to reassess the agency's management structure. James Webb, Hugh Dryden, and Robert Seamans had become dissatisfied with the November 1961 reorganization. Headquarters had failed to secure the strong program direction over Apollo that Webb had wanted. When hardware development problems continued to mount, with attendant escalating costs and slipping flight schedules, something very definitely had to be done. Moreover, having a program the size of Apollo, along with all the other programs NASA was pursuing, made it difficult for one man - Seamans in this case - to serve as "general manager" over day-to-day affairs. In 1961, Webb had needed decision makers at the program level, but in 1963 he needed this talent, armed with the proper authority, at the administration level to unify the agency, provide direction to the field centers, and lessen some of the autonomy the latter had held onto so tightly. The major change involved putting the field centers under Headquarters "Associate Administrators" for special activities - George Mueller for Manned Space Flight, Homer Newell for Space Science and Applications, and Raymond L. Bisplinghoff for Advanced Research and Technology - rather than under the Associate Administrator as they had been. Mueller, who had replaced Brainerd Holmes as chief of manned space flight, now took charge of both the program and the centers carrying it out - MSC, Marshall Space Flight Center, and Launch Operations Center. Mueller also set up a Gemini Program Office in Washington,** chiefly as a device to oversee Gemini and to bring together in a single group all those in NASA Headquarters whose work related to Gemini. William Schneider had taken over a tiny liaison office of seven people from Colonel Daniel D. McKee earlier in the year. Now he headed a program office seven times that size. Several months would elapse before the effects were felt in Houston.2 In the meantime, some of Gemini's most severe technical problems were at last beginning to respond to hard work in the field.
Titan II Makes the Grade, But Not Paraglider
What had been Project Gemini's greatest concern - whether Titan II could function as a booster for manned space flight - was soonest laid to rest.  Titan II Missile N-25 was launched 1 November 1963 from the Atlantic Missile Range, the 23rd in the series of test flights conducted by the Air Force Ballistic Systems Division (BSD). It furnished the first real proof that Titan II would do for Gemini. Missile N-25 was equipped with the standpipes on its oxidizer lines and mechanical accumulators on its fuel lines that the revised theory had predicted would suppress the severe length-wise bouncing (Pogo) that threatened Titan II's role as a manned booster. The November flight proved it worked. The devices installed in fuel and oxidizer feedlines reduced Pogo to the lowest level ever in a Titan II flight, only one-ninth the force of gravity (±0.11g), and for the first time well below the ±0.25g that NASA insisted marked the upper limit for pilot safety.3
The Gemini Program Office had no way of forecasting that the next five months were to see the Titan II test flight program produce an unbroken string of successes. But, knowing that standpipe and accumulator had worked on Missile N-25, GPO inferred that the theory behind installing these devices had been confirmed and acted quickly, sure that the Pogo problem had been solved. On 6 November, GPO decided to procure several sets of the suppression devices for Gemini launch vehicles. The soundness of that action was soon confirmed. Titan II launches on 12 December 1963 and 15 January 1964 both carried the oscillation dampers and both met NASA standards. The 15 January flight, added at Aerospace urging, proved the devices effective even with reduced fuel-tank pressures. This was all the more heartening because raised tank pressures had lowered Pogo levels in some earlier missile flights.4
While Titan II was proving itself in flight, NASA and the Air Force completed their nearly year-long efforts under the aegis of the Gemini Program Planning Board to fix standards for the Gemini launch vehicle. NASA's final statement, on 15 November 1963, rehearsed its long-stated demands: longitudinal oscillations during powered flight must be no greater than ±0.25g, incipient combustion instability must be eliminated, and all known design shortcomings and anomalies revealed in Titan II ground and flight tests must be corrected. On the same day, BSD and SSD (Space Systems Division) of the Air Force Systems Command issued a plan to prove in flight their program to reduce Pogo and improve engines. These two documents, along with the earlier Air Force plan for cleaning up Titan II problems, answered the board's request of 11 October 1963 for data on  which to base a formal Memorandum of Understanding between NASA and the Air Force.5
What NASA required and how the Air Force planned to respond were discussed for the last time at the board meeting of 3 December. The board accepted the NASA specifications as reasonable, the Air Force plans to resolve the problems and verify the results as technically feasible. Then the co-chairmen of the board, Brockway McMillan for the Department of Defense and Robert Seamans for NASA, signed the formal "Memorandum of Understanding on Certain Design Requirements for the Gemini Launch Vehicle."6 No further managerial obstacles blocked the way to a man-rated Gemini launch vehicle.
The compound of jurisdictional disputes and technological problems that had made the launch vehicle the single biggest question mark in the Gemini program until late in 1963 vanished almost overnight. By mid-January 1964, Titan II no longer seemed a concern. After the missile's third success with Pogo suppression gear, on 15 January, Seamans was convinced "that the currently completed flight demonstrations of POGO fixes indicated a qualitative understanding of the problem and its solution and provided sufficient confidence to go ahead with the Gemini program." Another sign of the times was the end of the weekly Titan II status reports Seamans had been getting from Air Force Systems Command because, "based on the successful resolution and flight verification of the axial oscillation fix (Pogo) on missiles N-25, -29, and -31, the primary requirement, for which this weekly report was originated, has been satisfied."7
Pogo had not, of course, been the only problem, although it was the greatest. Still to be resolved was the potential instability of Titan II's second-stage engine, which Aerojet-General had begun to tackle in October 1963 with Gemsip, the Gemini Stability Improvement Program, focused on working out a new design for the propellant injectors. Gemsip ended 18 months later with complete success, having cost the Air Force about $13 million. NASA spent $1.45 million to install the changes in the last six Gemini launch vehicles. The first six flew with the old-style injectors, which NASA later defended on the somewhat specious grounds that no instability had shown up in a Titan II flight. That was essentially a statistical argument of the kind earlier rejected as a basis for man-rating. NASA found a better reason for going on with the flight program. Aerojet engineers knew that any number of techniques might be used to reduce starting shocks, the major trigger for unstable burning. Very early in Gemsip, they found that a certain minimum pressure in the cartridges that started the motor eased the problem. Temperature conditioning - keeping the start-cartridge temperature above a critical value - proved even more effective. This was the finding that chiefly convinced NASA that Titan II's second-stage engine was safe enough for manned missions,  although only Aerojet's redesigned injector finally provided a dynamically stable engine.8
NASA's third concern about Titan II had been just how reliable some engine parts were. This was less a matter of design than of the general standards of manufacturing and quality control observed by Aerojet-General. The Air Force, however, saw potentially dangerous weaknesses in design that demanded the development of new parts, an effort that got under way in September 1963 as the Augmented Engine Improvement Program. NASA deemed improved engines nice but not vital (as damped Pogo and stable second-stage engines were) for Gemini. This was just as well, because the engine improvement program produced small results for the $11 million it cost the Air Force: some minor design shortcomings corrected, welding techniques improved, and better assembly methods adopted. NASA did buy one product of the program for Gemini, redundant shutdown circuitry, at a cost of $1.5 million. But the rest of the hardware developed under the program looked more risky than what it was intended to replace. The Air Force canceled the program in November 1964.9
Looking back, NASA officials had nothing but praise for the hard work put in by the Air Force and its contractors to man-rate Titan II for Gemini even while they were trying to prove it as a missile. As George Mueller reported to NASA Administrator James Webb:
In the broad view of this booster program where a military vehicle, the Titan II, was selected prior to its development and a program of man-rating carried out actually in parallel with the flight test and acceptance of the military versions, we have, I believe, a unique situation. It is unique not only in technical complexity but also in management relations and control. . . . [T]his collaboration between two demanding users has produced an unusually reliable military launch vehicle . . . [and] a man-rated launch vehicle with a remarkable record of success. . Configuration management is not a new term but the detailed application of the Air Force to the GLV [Gemini launch vehicle] development is a model of its kind and a significant contribution toward improved management of all major programs, in DOD and in NASA. We have seen major improvements in electrical circuit design, in electrical soldering and welding techniques, in assembly procedures and in test specification.10
This picture of a smoothly meshed team moving from success to success, although true enough for the last six months of the program, slighted the obstinate technical and managerial problems that had to be surmounted before the happy outcome was reached.
Even in retrospect, the record of Titan II research and development flights was spotty, especially in view of the high promise that had induced NASA to choose it for Gemini in the first place.  Only 22 of the 32 flights that comprised the test program would have succeeded in launching a Gemini mission. Based on Titan II flight tests, in other words, every third or fourth Gemini mission would have been abortive; this does not include the Pogo that rattled missiles during first-stage flight without compromising Air Force test objectives. This picture was, nevertheless, far brighter than it had been in mid-1963 - half the 20 tests flown by 20 June would have been failures on Gemini. The concentration of all 10 unsuccessful flights in the earlier part of the program, however, may have held the greatest promise. The unbroken string of 12 nearly flawless flights that concluded the Titan II test program strongly implied that the missile's problems had, in fact, been solved. With Pogo reduced to tolerable levels by techniques that accorded with theoretical analysis, the threat of combustion instability eased by an operational expedient, and a series of successes to show that other troublesome areas had been cleared up, Titan II could be judged man-rated in the early spring of 1964. This judgment seemed amply confirmed by Gemini-Titan 1, launched 8 April 1964,* the day before the last flight in the missile's research and development test program and well before men were first scheduled to ride the Titan.11
The striking vindication of Titan II in the final months of 1963 had no parallel in the paraglider program. Paraglider's only chance to regain a place in Gemini hinged on the outcome of North American's new series of deployment flight tests with the full-scale vehicle. A full-scale wing was to be uncased and inflated in midair, to prove it could support the vehicle in stable gliding and maneuvering under radio control. Each of the planned 20 tests was to end with the wing cut loose at 3,000 meters and the test vehicle landing by parachute. The parachute system was qualified on 3 December 1963, clearing the way for flight testing of the full-scale vehicle to begin on 22 January 1964. The first test did nothing to dispel doubts about paraglider; the second test, on 18 February, was also a failure.12
That same day, George Mueller told the House Subcommittee on Manned Space Flight that the paraglider "is not presently scheduled on the . . . Gemini spacecraft."
"Will it be used at all in the Gemini program?" one of the Representatives wanted to know.
Mueller replied, "That will depend upon the development status of the paraglider which we will evaluate next spring. It will also depend upon the needs for a paraglider for precise landing of the Gemini spacecraft which we are developing now with the Air Force."
Further probing revealed that paraglider could be ready for the tenth Gemini mission, particularly if the Department of Defense lent  its support - this from George Low. But, he added, "we have no money included [in] 1965 or beyond for the paraglider under the assumption we will not go into production."13
NASA's public position was that, while land recovery appeared to be both desirable and feasible, it was riskier than water landing. Crew safety, the paramount concern, dictated the proven mode of safer landing for all 12 Gemini flights.14 The risks of land recovery were real enough, needless to say, but they had been just as real in 1961 when NASA decided to adopt land landing as a major Gemini objective. Toward the end of winter in early 1964, however, the means to that end, a paraglider landing system, had yet to achieve a level of performance great enough to rely on. After nearly three years of work, there was still no certain answer to the key paraglider problem - how to unship and inflate the wing from a two-tonne spacecraft plunging downward through the atmosphere. The risk that loomed so large early in 1964 was perhaps not so much land landing as paraglider landing.
Paraglider still had ardent defenders in NASA, and the decision to strike it from Gemini was not yet final.15 But NASA was ready to drop the paraglider, the more so since the system might still fly in another version of Gemini. In the spring of 1963, under the auspices of the Gemini Program Planning Board, the Air Force had begun laying the groundwork for its own Gemini program. Gemini B/Manned Orbital Laboratory (Gemini B/MOL). The Air Force X-20 orbital glider, still often called by its former name, Dyna-Soar, had been canceled in December 1963, a victim of low priorities and lagging development. Some X-20 funds were diverted to the new MOL program, which projected two men in a modified Gemini spacecraft launched by a Titan III. In orbit, the crew would transfer to a separately launched laboratory for two to four weeks, after which they would return in their spacecraft.16
Air Force planning had progressed far enough by January 1964 to require a formal agreement between NASA and the Air Force in the form of a memorandum signed by Seamans for NASA and Harold Brown for the Air Force.17 Although Gemini B/MOL would not be officially approved until August 1965 and design work was only beginning, NASA saw a chance to save paraglider. On 17 March 1964, George Mueller asked the Air Force for "an expression of the DOD interest in this capability," whether for Gemini B/MOL or any other program. Six weeks later, having concluded that paraglider development had too many problems to warrant putting it in the new program, the Air Force discounted any prospect of joining in paraglider development and threw the problem back to NASA: "Should the NASA qualify and demonstrate the paraglider in the NASA Gemini program, consideration would be given to its application to the Gemini B/MOL."18 By then, however, it was too late.
 North American's further efforts to fly the full-scale test vehicle produced a string of failures, each distinct in detail but united in a single root cause, "an inability to adequately predict the wing loads of flexible structure[s]." The fifth failure in a row, on 22 April, was the last straw. The next day, William Schneider, NASA Headquarters Gemini chief, informed George Mueller that he planned to transfer what was left of the paraglider program to Flight Research Center and to spend no more Gemini money. A week later, the program office in Houston began cutting back paraglider work and phasing the program out of Gemini. Early in May, GPO and North American agreed to run the rest of the flight-test program with the equipment and money already committed. Paraglider was dead as far as Gemini was concerned, although a public statement of its demise waited until 10 August.19
Ironically, North American achieved its first full-scale test vehicle success on 30 April, the day after phasing it out of Gemini began. In fact, the worst was over. Before the end of 1964, North American flew 19 more tests for a total of 25, 5 more than originally planned. By July, the deployment sequence was no longer giving much trouble, although a stable glide after the wing inflated was harder to manage. The last three flights, however, displayed the complete sequence without flaw.20
The last full-scale test vehicle flight was on 1 December 1964. Two days later, NASA told North American there would be no more money for flight testing, but equipment on hand might be used, if the company cared to spend its own money. North American seized the chance to complete the other major portion of the May 1963 program - working out landing techniques with a piloted tow-test vehicle. Tow-testing had begun during the summer. On 29 July, a helicopter had towed the vehicle up to a height of a few hundred meters, around the test area, and back to a safe landing. A free flight followed on 7 August, but the vehicle went into a series of uncontrolled turns, forcing the pilot to bail out. North American attacked the problem with dispatch and came up with an altered wing design. On 19 December, a pilot flew the tow-test vehicle through the complete test to a safe landing.21
NASA had long since decided to dispense with paraglider for Gemini, however, and that was irrevocable.** 22  The system's shortcomings, or at least North American's slowness in coming up with answers, account chiefly for paraglider's failure to survive in Gemini. But the immediate reason for the abrupt action in the last week of April 1964 to kill what remained of the Gemini paraglider may have had more to do with money than with technology.
Money and Management Problems Again
Gemini's chronic budget ills were marked from time to time by acute episodes. The crisis of late 1962 had scarcely subsided before the project reeled under a new round of cost increases. By 8 March 1963, the program's total price tag stood at just over $1 billion. NASA's projected budget for fiscal year 1963 had been $232.8 million after the impact of reprogramming had been assessed; actual expenditures topped $289 million. The pattern repeated in fiscal year 1964, with a planned budget of $383.8 million exceeded by $35 million. By 2 March 1964, NASA expected to spend over $1.2 billion on the program.23 These increases reflected, in part, Gemini's changing scope and the technical problems that somehow proved harder to solve than anyone had expected. They also reflected, perhaps inevitably in so large and complex a program, mistakes, errors of judgment, and mismanagement, though Gemini appears to have suffered less from those ills than other programs of comparable size. Swelling costs were, for whatever reason, evident throughout the program.
NASA and McDonnell had finished negotiating the Gemini spacecraft contract in February 1963, settling on a total cost plus fixed fee of $456,650,062. This figure was not so firm as it then seemed. At the end of 1963, McDonnell estimated total spacecraft costs at upwards of $612 million. Something less than half the difference could be ascribed to approved changes in the program, as exemplified by the $2.7-million price for adding drogue stabilization to the parachute recovery system, though this change was itself prompted by development problems with reentry thrusters. Much of the balance derived from cost overruns on major Gemini subcontracts, with thrusters by Rocketdyne and fuel cells by General Electric the chief culprits. The new year brought no relief. In March 1964, when NASA estimated the total cost of Gemini at $1.2203 billion, the spacecraft accounted for $667.3 million.24
Launch vehicle budgets were equally ephemeral. The billion-dollar estimate of March 1963 had included $240 million for the Gemini booster. As the year wore on, Air Force Space Systems Division found the situation "extremely fluid. Costs were constantly increasing and changes were being approved so fast it was difficult to keep track of them. . . .  Engine problems were causing late deliveries and increasing costs." When SSD completed its first comprehensive review of the Gemini budget in January 1964, it felt obliged to revise the cost upward to $296 million. Just two months later, after another hard look at launch vehicle costs, SSD claimed to need $324 million. This was the same month, March 1964, when NASA was counting the booster's share of a $1.2-billion Gemini budget as $281 million. Toward the end of the month, Gilruth warned Major General Ben Funk, SSD Commander, that MSC's 1964 booster money had been exhausted. With three months of the fiscal year still to go, the $46.9 million allotted looked as if it would fall $30 million short of expenses. Gilruth was much concerned about funding in the coming two years and asked Funk to take another look at his needs. Funk replied with an estimate of $332 million that included $75.3 million for fiscal year 1965, $8.4 million higher than NASA had planned.25
Inexorably rising costs plagued target vehicle as well as launch vehicle development, and for much the same reasons: technical problems compounded by the fact that NASA and the Air Force simply did not agree on how a development program ought to be managed. NASA wanted more control than the Air Force thought wise to impose. NASA efforts to promote its view during late 1963 had availed little, and Mathews' communications with SSD grew more caustic. On 5 February 1964, he scored Bell and Lockheed (and, by implication, SSD) for the sorry job being done on Agena engine development. Costs had "continued to increase even at this late date to a level far beyond that considered reasonable by this office." The excuses offered were, in Mathews' view, worthless:
The emphasis which BAC [Bell Aerosystems Company] has placed on the fact that the development effort was to be one of minimum cost has apparently led them to a belief that sound technical judgment was no longer required or that minimum cost eliminated its use. The GPO does not consider this argument valid or useful.
The fault was as much Lockheed's as Bell's. Mathews believed that -
the costs quoted by BAC and submitted by LMSC [Lockheed Missiles & Space Company] are excessive or unjustified in many areas. Moreover, these costs have increased and are continuing to increase with apparently little financial hazard to BAC and only after-the-fact recognition by LMSC. . . . GPO must express dissatisfaction with LMSC and BAC management of these programs.26
Engine development costs were only part of the problem. The first "firm" budget for the Gemini Atlas-Agena program was ready in September 1963. SSD projected a total cost of $103 million, with Agena's  share as $57.5 million. By March 1964, NASA was prepared to spend $137 million for the program, $93 million on Agena alone. The $37 million programmed for Agena in fiscal year 1964 was almost exhausted, although that figure was $2.4 million higher than Lockheed had, in September, claimed to need. Mathews termed the situation "critical" and demanded a complete explanation in writing for the discrepancy between current costs and the September projections. GPO once again saw, in "the contractor's frequent increases in the estimated costs," signs of "a serious need for improvement by the contractor in proper planning and cost control." Mathews warned SSD and Lockheed that "lack of adequate cost control places this program in real jeopardy."27
Ironically, at the same time that Mathews was urging SSD to get Lockheed under control, the contractor was finding that it needed still another $2.5 million in 1964 funds, a request that was duly passed along to GPO on 4 April. Lieutenant Colonel Mark E. Rivers, Jr., who had just replaced Major Charles Wurster as chief of Gemini-Agena engineering for SSD, saw signs of sloppy management in the new Lockheed request, which appeared to be based on small changes that had piled up unnoticed over several months.28
This, then, was the setting in April 1964 when North American, for the fifth time in a row, failed to deploy the paraglider wing in flight. Mounting costs in all phases of Gemini development had stretched the 1964 budget to the breaking point, and the trend was still upward. Paraglider had been budgeted for $16.4 million in 1964, but that would be the last of the money. Keeping paraglider meant finding new funding or cutting back other parts of the program. In the money budget as in the weight budget, once paraglider's status became doubtful, its place was preempted. Against this confluence of forces - technical, operational, and budgetary - paraglider could not stand.
Whether the target vehicle program could survive was also a question. In late April, budget pressures forced Mathews to discuss with his staff some desperate measures. Paraglider, Atlas-Agena, and even one of the planned Gemini missions were on the chopping block. Once again, however, MSC was able to reprogram funds to save the full 12-flight program and, via Agena, the rendezvous objective, if not paraglider and land landing.29 One of the factors that may have made Agena's place in Gemini shaky in April 1964 was a new round of technical problems that had cropped up earlier in the month.
Bell's efforts to complete development testing of Gemini-Agena propulsion systems during 1963 had produced spotty results and many delays, which had, in turn, postponed the start of preliminary flight rating tests of these systems. Scheduled to begin in June 1963, testing of the main engine had been put off until January 1964 but began only on 6 February. Still another two weeks elapsed before the  secondary system began its tests on 17 February. Both programs soon ran into trouble.30
Main engine testing proceeded with only minor problems through the first week in April. In the following week, however, the test program encountered what proved to be a six-week delay when the test unit's fuel and oxidizer start tanks failed. These tanks were stainless steel canisters with bellows inside them to push the propellants that started the main engine. Visible lengthwise cracks in their outer shells allowed the gas that was supposed to force the propellants from the tanks to escape. The steel in the shells had corroded. Tanks with a new heat-treated steel shell replaced the defective tanks, and testing resumed in May. But the tests, which should have ended in April, ran into late June. Alarmed by the threat of increased cost such a failure implied, GPO demanded a complete written account of the causes and effects, a point of special concern being "indications that subcontractors may have failed to process materials in a manner essential to the proper operation of components being developed."31
Agena's secondary propulsion system, like the main engine, started preliminary flight-rating tests smoothly, then ran into trouble early in April. Failure of a propellant valve, however, imposed only a minor delay. A harder problem emerged later in the month during high temperature firing, when the wall of a thrust chamber burned through after 354 seconds. While well beyond the 200 seconds regarded as the system's longest useful life in orbit, it fell below the specified time of 400 seconds. Bell installed a new thrust chamber and finished the tests - in mid-August instead of the scheduled mid-June. The failure, however, needed to be explained, and that meant more tests. Bell planned a series of six tests over two weeks, beginning early in September. Test-cell problems hampered the work, which did not end until mid-November and then after only four tests. The four were, however, enough to spot the problem - elevated propellant temperatures - and to show that it would not affect the system's performance in orbit.32
Bell's slow progress in its test program delayed Lockheed's testing. Because of the scope of changes in propulsion systems required to adapt the standard Agena D for Gemini, Lockheed planned a series of static firings using an Agena skeleton fitted out with propulsion and propellant systems at its Santa Cruz Test Base in California. Lockheed received the propulsion systems from Bell in February and March and had the test assembly at Santa Cruz by the end of March. Checkout problems and Bell's cracked start tanks in April held up the testing. Lockheed returned the main-engine start tanks to Bell, but they were not replaced until mid-May. Other minor problems delayed the first firing until 16 June. Once under way, however, the test program moved quickly to an end on 7 August 1964 with no further mishaps.  Post-test analysis confirmed that the propulsion systems had come through in fine shape.33
In the meantime, doubts about the Agena's ability to perform its mission had been growing. On 15 April 1964, SSD suggested flying a non-rendezvous Gemini-Agena mission to bolster confidence. GPO dismissed this scheme but accepted an alternative recommendation that one target vehicle be assigned the role of development test vehicle. This would be helpful for troubleshooting malfunctions and testing changes and would also allow further development testing, should the need arise. The plan was approved in May and the first Gemini Agena target vehicle, GATV-5001, was to be the test vehicle. AD-71, the first standard Agena D for Project Gemini, had been accepted by the Air Force on 30 April and transferred to the final assembly area at the Lockheed plant, where it was being converted to GATV-5001. Despite its new role, GATV-5001 was expected to remain in flight status until GPO decided otherwise, although GATV-5002 was now tentatively scheduled for the first rendezvous mission. GATV-5001 was not likely to fly unless GPO later opted for a non-rendezvous mission. So GPO canceled one of the eight Atlas boosters then under contract as Agena launch vehicles, saving the program $2.15 million.34
A Set of Breakthroughs
The three spacecraft systems that had caused the most trouble in 1963 - escape, fuel cell, and thruster each enjoyed a sharp change of fortune as the year turned. Problems that had resisted the best efforts of NASA and contractor engineers for so many months suddenly yielded. All the answers were not in yet, but by the spring of 1964 the prospect that any of these systems might fail to meet Gemini needs had largely vanished.
Escape system development trials had come to a halt in August 1963 as the system went through another series of design changes and some of its key parts, particularly pyrotechnics, remained hard to get. Active testing resumed on 22 November, with the first in a projected series of about 30 drops of the ballute, which had been added to the crew parachutes for the sake of high-altitude stability. The first 10 tests, which involved both men and dummies and used a ballute 91 centimeters (36 inches) in diameter attached by a single riser, ended on 9 January 1964. In each case, the subject spun too rapidly on the riser.* This was solved by raising the ballute diameter to 122 centimeters (48 inches) and using two-point suspension.  Fourteen more drops over the next few weeks, the last on 5 February, confirmed the changes, and the ballute was ready for its qualification tests.35
Only two days later, sled-ejection development trials also came to an end. Testing had resumed with the fourth run, on 16 January, and ended with the fifth, on 7 February. Everything worked in both tests. Since simulated off-the-pad and ballute development tests had already been completed, the successful 7 February test brought the development phase of escape-system testing to a close.36 Neither fuel cell nor thruster was so far advanced.
Fuel-cell production had stopped in late November 1963, as a pair of GE task groups sought to resolve the system's stubborn engineering and manufacturing problems. Within six weeks they had finished their work, which furnished the basis for turning the program around. Everyone involved in the fuel-cell program gathered in Houston on 27 January 1964 to review development status and decide what to do about it. All agreed that the system needed redesigning. The current PB2 model was to be discontinued; the units already built were to be used for limited testing and to be carried in Spacecraft 2 to gather data and help qualify the reactant supply system. All future cells were to be the new P3 design, and they were to be installed in every spacecraft beginning with the fifth.37
Major changes in the new model reflected the narrow technical nature of the problems: dams (or baffles) were added to improve hydrogen distribution; the water collection wick was removed from each cell; and the orifice of the hydrogen feed tube of each unit was restricted so that any stoppage caused by water clogging could be cleared. Other changes included adding Teflon to the electrode to cut the loss of active material from the membrane and an anti-oxidant to the membrane to slow the rate of polystyrene breakdown. Tests had also suggested that the crucial problem of short operating life might respond to reduced temperatures. When further tests confirmed this finding, the coolant supplied to fuel cells was adjusted for lower temperatures.38
Although fuel-cell problems were largely technical, GE decided the program could be better managed. It reorganized the Direct Energy Conversion Operation to work solely on the Gemini fuel-cell program. Roy Mushrush, the new manager, had a background as corporate troubleshooter for GE. He arrived on the scene with a blank check on the company's resources for whatever help he needed. Mushrush was seconded by Frank T. O'Brien as Gemini manager. Both men impressed a NASA visitor with their enthusiasm, and morale throughout the plant remained high despite the shakeup.39
The fuel-cell program was still a question mark, and no one could be fully certain that the system would be ready in time for Gemini. But in the early spring of 1964, the program's technical and managerial  problems seemed to have been taken in hand, and prospects were a good deal brighter than they had been. By the end of May, GE had finished switching to the P3 design and had started a broad test program.40
Rocketdyne's thruster development program was also turning a corner. So far, attempts to improve performance had been little more than stopgaps, centered chiefly on cutting the engines' thermal load by dropping the ratio of oxidizer to fuel. But lower working temperatures and longer engine life were being achieved at the expense of combustion efficiency and specific impulse. This was one of three major topics discussed at a review of thruster problems in Houston on 23 December 1963. Rocketdyne was directed to cut the current oxidizer to fuel ratio of 1:1.3 still further, if that could be done without harm to good starting and stable burning.
Study of another expedient was also approved: shifting the sidefiring thrusters to align them more closely with the spacecraft center of gravity and so reduce demands on the smaller attitude thrusters in holding spacecraft attitude during lateral moves. Development of this small engine was the least hopeful aspect of thruster work - no one really understood what its design ought to include, and tests produced large and hard-to-explain variations. No attitude thruster had yet shown itself able to fire through a complete mission duty cycle without failure.
A third decision, of greatest impact on grew out of the 23 December review. André Meyer, chief of GPO administration, had been urging a change in the design of the ablation material lining the thrust chamber. A newly developed parallel-laminate material showed promise as an answer to thruster-life problems. Meyer wanted the laminates oriented nearly parallel to the motor housing, instead of perpendicular as before. His efforts to convince both McDonnell and Rocketdyne to make this change had been resisted because of its expense, but now, strongly backed by MSC Director Robert Gilruth, the idea was accepted and an engine to test the concept was ordered built.41
The thruster picture brightened perceptibly over the next month. Further tests confirmed that reduced oxidizer-to-fuel ratios prolonged engine life, bringing the maneuvering thrusters within sight of their required mission duty cycles. The performance of the smaller attitude thrusters also improved, though not as much. By mid-January 1964, NASA Headquarters felt sanguine about the prospects for Gemini's big thrusters but saw little hope for so happy an outcome to the development of the smaller thrusters. There was strong support for a study of a radiation cooled engine as a backup.42
Meanwhile, Rocketdyne's efforts during the last two months of 1963 to work out the basic problems of small ablative engines had also borne fruit. A search through the files uncovered a research report on  the problem of heat flux in small engines and an answer in the technique of "boundary-layer cooling." The injector of a maneuvering thruster was modified to spray about a quarter of its fuel down the walls of the thrust chamber before firing. On 25 January 1964, Rocketdyne tested the engine through its full mission duty cycle without failure, its liner charring only to a depth of little more than a centimeter (one-half inch). A second thruster produced the same results. Since the lining of the flight weight engine was twice that thick, the margin seemed ample. Buoyed by these results, GPO, after a meeting at the McDonnell plant in St. Louis on 13-14 February, ordered McDonnell to have boundary-layer cooling designed into the larger thrusters in time for Spacecraft 5.43
The smaller attitude thrusters did not respond as well to boundary-layer cooling, although it helped. A modified injector, combined with an oxidizer-to-fuel ratio of 0.7:1, allowed one small engine to survive a 570-second firing on 15 February with some of its liner intact; in earlier tests with the same ratio but without the injector, the liner had not lasted beyond 380 seconds. Two flight-weight engines with the new injector and lower ratio lasted for 435 and 543 seconds. Another change made these results look even better. Canting the lateral engines to direct the thrust vector closer to spacecraft center of gravity (as suggested at the 23 December meeting) was shown to reduce the thruster life needed to less than 400 seconds.44
By mid-March 1964, thruster development and qualification appeared likely to be completed in time, though without much leeway to handle any new problems and with performance that was still marginal. In April, that status was transformed. Thrust chambers lined with laminated ablative material oriented almost parallel (at an angle of only 6 degrees) to the motor housing achieved dramatically better performance. The first modified attitude thruster endured 2,100 seconds of burning without failure on 14 April, a fourfold increase over the best prior test. And the next day, a maneuver thruster with boundary-layer cooling and the 6-degree wrap fired for 1,960 seconds, the test ending only when fuel was exhausted. Just as striking was the first test of a lateral thruster with the new wrap: 3,049 seconds of firing time without failure. George F. MacDougall, Jr., Deputy Manager of Program Control in GPO, reported the results to the MSC senior staff as "a major breakthrough."45
Convinced that the answer had been found, GPO lost no time. Within two days after the first tests of the small and large thrusters, McDonnell and Rocketdyne had orders to replace 90-degree with 6-degree wraps in all thrusters and to see that the new thrusters were' installed in the orbital attitude and maneuvering systems of all spacecraft beginning with the fifth and in the reentry control systems of all spacecraft as soon as possible. By 1 May, however, Spacecraft 5 looked  too early for a complete set of new engines. Instead, all its attitude thrusters would have the modified injector and 6-degree wrap, but only the aft-firing maneuvering engines would feature the new design. The less critical lateral- and radial-firing engines would be the old model. All thruster designs were now frozen, with further testing limited strictly to qualification.46
Rocketdyne was by no means home free, but the worst of the spacecraft propulsion systems' technical problems did appear to be over by the spring of 1964. The fuel cell also seemed to be in good shape. Gemini's escape system, already through its development test program, may have looked best of all. As later events were to show, the promise was not quite that easy to fulfill. But none of these three most stubborn systems was slated for the first Gemini spacecraft which McDonnell had been building in its St. Louis plant.
Toward Gemini-Titan 1
The primary objective of the first Gemini mission, as it emerged from the revised flight program of April 1963, was to prove the Titan II able to launch the Gemini spacecraft and put it into orbit within the constraints imposed by manned space flight. To gather and report data were the spacecraft's main functions. Spacecraft 1 was, therefore, unique among the products of the Gemini assembly line in St. Louis in being largely without standard spacecraft systems. For the most part, it carried dummy equipment and ballast to match normal weight, center of activity, and moment of inertia. Structurally, however, Spacecraft 1 differed from later models in only one important respect. Since mission plans did not call for the spacecraft to be recovered, the heat-shield simply completed the structure. Four large holes bored in the ablative material ensured the total destruction of the spacecraft when it plunged back into the atmosphere.
Working equipment was mounted on two special pallets (much like the "crewman simulator" used in Project Mercury) located where the crew would be in later flights. Spacecraft 1 carried two active Gemini systems: a C-band radar transponder and related gear to help ground radar keep track of the spacecraft, and three telemetry transmitters to return data to Earth. Data were to be gathered by a set of special instruments that measured pressure, vibration, acceleration, temperature, and structural loads.47
McDonnell began testing Spacecraft 1 on 5 July 1963, with plans to have it at Cape Canaveral by mid-August. The first phase of spacecraft systems tests centered on making sure that each working piece of equipment functioned properly. Many parts did not, bringing testing to a halt on 21 July. The instrumentation pallets had several defects, especially in their electrical circuits and in their response to vibration.  Other problems included a transmitter and a radar beacon that had to be returned to their makers to correct out of specification performance. With these matters taken care of, testing resumed on 5 August and proceeded smoothly to the end of the first phase on 21 August.48
Four days later, McDonnell workmen mated the major spacecraft modules. The now fully assembled vehicle was ready for the second phase of systems tests, checking its overall working and the compatibility between the mated sections. It was now slated to arrive at the Cape on 20 September. During the first half of the month, tests alternated with leftover manufacturing tasks, which slowed things down, but not seriously. All systems performed well during the last half of the month, as the spacecraft was vibrated to simulate a launch, then transferred to the altitude chamber for simulated flight tests under orbital conditions. A complete integrated systems test on 30 September concluded the testing.49
A good share of the program office and a sampling of the rest of NASA were on hand the next day to watch Spacecraft 1 as it rolled out of the test area in the McDonnell plant. Throughout the morning, McDonnell experts lectured their NASA guests on the spacecraft, the status of each of its parts, and the results of testing. After lunch, the NASA party retired behind closed doors to ponder the fate of the spacecraft. The McDonnell staff gathered late in the afternoon to hear the decision. Spacecraft 1 had been accepted for shipment to the Cape.50
When it arrived on 4 October, it entered a new round of testing. GPO had decided early in the program that Gemini preflight checkout would conform to the Mercury pattern, even though the two-man spacecraft had been designed to render that kind of repeated testing unnecessary. Plans called for the spacecraft to be broken down to its major modules, each of which was retested to the subsystem level. After being put back together again and passing a series of integrated tests culminating in a simulated flight, the spacecraft was to be transferred from the industrial area to the launch complex.51
Spacecraft 1, lacking most of Gemini's normal systems, was much easier to check out than later models; by the evening of 12 February 1964, the task was finished. The next step was a formal Preflight Readiness Review of spacecraft status, both physical and functional. Gemini Manager Charles Mathews and a team of engineers from Houston and Cape Kennedy* conducted the review on 18-19 February,  finding nothing that would prevent the spacecraft from being moved to the launch complex nor that seemed likely to delay the launch.52
The launch vehicle was not ready for mating, so Spacecraft 1 waited until 3 March before its transfer to complex 19. While the spacecraft waited, minor work continued, especially on the spacecraft shingles. These beryllium shingles were part of the heat protection structure and covered the external surfaces of the two forward modules - the rendezvous and recovery canister and the reentry control system. A fully acceptable fit was not, in fact, achieved until after the spacecraft had been mated to the launch vehicle.53
Building and testing the first Gemini launch vehicle was not as easy as getting the spacecraft ready, because GLV-1 had the same role as the later boosters in the program. Just as McDonnell had been building spacecraft despite hard-to-resolve problems in some spacecraft systems, the Baltimore division of Martin- Marietta had been building launch vehicles for Gemini, even during the long months when the Air Force and its contractors were struggling to make Titan II reliable.**
Titan II was built around its propellant tanks, one for fuel and one for oxidizer in both the first and second stages. Martin's Denver division, which held the missile contract, provided the tanks for Gemini boosters as well and shipped the set for GLV-1 to Baltimore in October 1962. After a lengthy series of tests, with special attention to welded joints to be sure they were both strong enough and leakproof, the tanks were ready for formal inspection in mid-February 1963.*** Only three passed. The second-stage oxidizer tank was cracked. It was returned to Denver and replaced by the tank intended for GLV-2, which reached Baltimore on 1 March.54
By 21 May, the first Gemini launch vehicle was fully assembled and ready to begin testing as a unit. A check for wiring continuity revealed a short circuit in the second stage where a wire's insulation had been cut through by a defective clamp. When inspectors found several other clamps with the same defect, every one of the more than 1,500  wiring-harness clamps in GLV-1 was removed, all wiring inspected, and a new set of clamps installed.55
When electrical continuity had been confirmed, the first stage was erected in Martin's new Vertical Test Facility on 2 June, the second a week later. This facility was a tower 56 meters high, adjoined to a three-story blockhouse fitted with test and checkout equipment, or AGE****, matching the AGE at complex 19 in Florida that would later ready GLV-1 for launch. The tower and blockhouse inside the Martin plant were designed to provide test data and to be compared with data gathered during checkout at the Cape.56
The first phase of the test program, subsystem functional verification to make sure that each of the vehicle's subsystems was working, began on 16 June. These tests went more slowly than planned. For one thing, the second stage had been late going up, partly because of electrical problems and partly because its engine arrived late. For another, minor troubles cropped up - hydraulic tubing that was not fully cleaned, solder flux that had boiled from a pinhole in a joint and gummed a gyroscope. By the end of June, subsystem testing had fallen about two weeks behind schedule, a source of concern but as yet no threat to the launch planned for December 1963. The functional verification tests lasted until late July, when a review of the data by SSD and the Aerospace Corporation found GLV-1 ready for the next phase of testing.57
GLV-1 began combined systems tests on 31 July with a series of tests designed to uncover any interference between the vehicle's several electrical and electronic systems. Five systems failed to meet standards after the first round of testing. Efforts to correct the problems - mainly by adding filters and grounds to Age and airborne circuits - produced results, though slowly. Only after the sixth test, on 5 September, was all interference cleared up. The launch vehicle's last hurdle was a combined systems acceptance test (CSAT), which included a complete launch countdown, simulated engine start, liftoff, and flight, and ended with the simulated injection of the spacecraft into orbit. After several practice runs in conjunction with the electrical-electronic interference testing, Martin conducted the formal CSAT on 6 September, then presented both the data and the vehicle to the Air Force on 11 September for acceptance.58
For the next week and a half, the Vehicle Acceptance Team, headed by SSD's Colonel Richard Dineen, met at the Martin plant in Baltimore. SSD, NASA, and Aerospace inspectors explored the vehicle  and studied its manufacturing and test records. This detailed inspection disclosed severe contamination of electrical connectors throughout, as well as a broken idler gear in the turbopump. These defects, plus the fact that 42 major components had yet to achieve documented flight status, forced the team to reject GLV-1. Failing to pass this type of inspection on the first try was not unusual, but it meant another long delay before GLV-1 reached the launch site.59
SSD and Aerospace members of Dineen's team also conducted a First Article Configuration Inspection (FACI) of GLV-1, with far more encouraging results. FACI had been a standard Air Force procedure since June 1962, a kind of audit of the actual product - as compared to engineering design - to provide a baseline for later products under the same contract. No SSD launch vehicle had ever made the grade on its first try, but GLV-1 did. Such defects as contaminated electrical connectors or broken gears, which barred its acceptance for Gemini, did not reflect discrepancies between design and product.60
No sooner was the inspection over than Martin technicians began to set things right. Armed with magnifying glasses, they searched every one of the 350 electrical connectors aboard GLV-1 for traces of contamination and found 180 needing to be cleaned or replaced. All flight control equipment that had produced transient malfunctions during CSAT was removed and analyzed. Defective units were replaced and wiring harnesses reinstalled. At the same time, Martin tried to complete documentation of failure analyses and qualification of flight hardware. This extensive reworking of GLV-1 invalidated most of the earlier test results. Martin's plan for an informal retest of problem areas only was rejected in favor of a full-scale repetition of CSAT. Subsystems testing and a preliminary acceptance test were finished by 2 October.61
The second formal acceptance test of GLV-1 ran on 4 October, uncovering little that needed to be corrected. Dineen's team reconvened at Baltimore on 9 October and took only two days to complete its work and decide that GLV-1 could be shipped to the Cape. The team was scarcely enthusiastic about the vehicle. Much work remained to be done on GLV-1, but it could be done at the Cape, and there at least GLV-1 could be helping to check out the launch complex itself.62
On 26 October 1963, GLV-1's two stages, each strapped to an eight-wheeled trailer, were towed to the Martin Airport, next to the plant, and rolled through the rear loading door of a huge C-133B cargo aircraft provided by the Military Air Transport Service. A four-hour flight brought the two stages to Florida. Still on their trailers, they were rolled from the aircraft into the hands of Joseph M. Verlander's Martin-Canaveral crew, who towed them to Hangar H to be unpacked, inspected, and fitted with the gear (such as lifting rings) required to erect them. There they remained, under guard, over the weekend.  On Monday morning, 28 October, the trailer bearing the first stage reached complex 19.
At the launch complex, the Martin crew trundled the first stage up the long ramp to the launch vehicle erector, which rested on its side parallel to the deck of the test stand. The trailer rolled through the large door (the roof when the erector was standing) and stopped a meter and a half (five feet) from the other end. The crew secured the stage, removed the trailer, and closed the roof-door. A 150-horsepower electric motor then winched the 127-tonne (140-ton) erector upright, a process that took several hours. The trailer-borne second stage arrived at the launch pad a day later. Ordinarily, the next step was mounting the second stage on the first, but GLV-1 was slated for a special static firing test in mid-December, the sequenced compatibility firing of both stages. So stage II was placed in the second-stage erector, a smaller structure used only for checkout or static firings, and the two stages were cabled together. After checking to be sure there was no interference, Verlander's team applied electrical power to the two stages standing side by side on 13 November.63
Work at the Cape on GLV-1 was already a week behind schedule. Problems in Baltimore had pushed the launch date from December 1963 to February 1964. Another two-month delay now threatened. Mathews announced himself "greatly concerned with the present situation regarding the Gemini Program at the Atlantic Missile Range." Four distinct groups - SSD, the Air Force's 6555th Aerospace Test Wing (in charge of all Cape launches), Martin-Baltimore, and Martin-Canaveral - were testing and checking out the launch vehicle, with no formal understanding on how responsibilities were to be divided among them. Clarification was not long in coming; but meanwhile matters had become so confused that two distinct Launch Test Directives had surfaced. To make things worse, NASA people at the Cape complained about lack of access to technical data from the contractors. Poorly meshed working groups compounded other problems - a time-consuming review of the official work plan, procurement snags, and, most serious, questions of compatibility between booster and AGE - which extended the planned number of working days to get GLV-1 ready for launch from 86 to 118. By 22 November 1963, Mathews had to tell Seamans that even the already late 28 February 1964 launch date was likely to drop back to 1 April although GPO was working hard to improve the prospect.64
In one move to help resolve management problems, Mathews united the several coordination panels that had been dealing with Titan II and related areas into a single Gemini Launch Vehicle Coordination Committee with six standing panels.#  All panels were to meet at the same time every third week, then report to the parent committee, which would decide what action was to be taken. That should mean no more delays caused by uncertain authority, duplicated effort, or conflicting decisions.65 Mathews and GPO launch vehicle manager Willis Mitchell also took steps to make good some of the time already lost. The Martin crew switched from two 8-hour to two 12-hour shifts a day. Checkout problems persisted, however, and the scheduled sequenced firing slipped from 20 December 1963 to 3 January 1964. Although a February launch of GLV-1 seemed out of the question, Mathews still hoped to launch by 17 March.66
But the problems refused to end. The combined systems test scheduled for l3 December was twice postponed and finally completed on New Year's Eve. Lack of compatibility between the booster and its support systems in complex 19, as well as a faulty turbopump assembly that had to be returned to Aerojet-General, were the major causes of delay. Next was the so-called wet mock simulated flight test, a complete countdown that included filling the propellant tanks; it was voided on 3 January by procedural errors after propellants had already been loaded. The test was called off two and a half hours before the simulated launch, although the count went on until T-30 (30 minutes before launch) to see if any other problems turned up and to give the operations crew some practice. Another try, on 7 January, was a success.
The countdown for sequenced compatibility firing was now set to begin, but a three and a half hour delay was imposed by contaminated oxidizer. Then, during the countdown, a malfunctioning first-stage propellant valve caused the test to be called off 20 minutes before firing. A second try, on 14 January, had to be canceled because unusually cool weather had chilled the engine start cartridges below the 275 kelvins (35°F) specified as the lower limit be Aerojet-General to prevent combustion instability. At last, on 21 January, the third attempt overcame some minor problems and delays to show the whole sequence of fueling, countdown, ignition and shutoff commands, guidance control, and telemetry. First-stage engines fired for 30 seconds and cut off. The second-stage ignited and fired for 30 seconds, halted by radio signal from the ground computer as in real flight. Sequenced compatibility firing proved that the engines delivered the required thrust and gimbaled properly. This static firing, the only one performed on a Gemini launch vehicle, met all prelaunch standards.67
 With static firing finally out of the way, the ground crew could now begin getting the booster ready for the spacecraft. That meant putting the second stage on top of the first, which was scheduled for 27 January. But post-firing cleanup found a defective rotor in one of the turbopump assemblies. Shipped to the West Coast for repair, it returned to the Cape on 29 January. Then a missing seal held up its reinstallation until 7 February.
The launch crew did not wait for the new seal; the turbopump assembly could be put back in the second stage after it was erected. On 31 January, they removed the stage from the small erector and secured it in the launch vehicle erector, which was then winched upright. The upper stage was gently lowered onto the first, and the two were bolted together. GLV-1 had assumed its final form. Before the spacecraft could be mated to the booster, there were still subsystem functional verification tests (like those done earlier in Baltimore) to be conducted. Although these tests were supposed to start on 14 February, lack of spare parts and questions about failure analyses imposed another week's delay. Once testing began on 21 February, however, it went smoothly to verify the launch vehicle's readiness for full systems testing by3 March.
On that day, Spacecraft 1 arrived at the launch complex to be installed in the spacecraft erector support assembly in a controlled-access "white room" atop the launch vehicle erector.68
Tightening Launch Schedules
The revised flight program of April 1963 had projected the first manned mission, Gemini 3, for October 1964. But as 1964 approached, that prospect was dimming. The first Gemini flight was held up by the late delivery and protracted testing of its booster, and Spacecraft 2 was falling behind schedule at the McDonnell plant. Efforts to install spacecraft test and checkout equipment at the launch site in Florida moved slowly enough to suggest that time might be too short there as well. The already certain delay of the first mission, added to the all-too-likely chance that the second would also be late, made the prospects for launching Gemini 3 in 1964 look poor.69
At a meeting on 13 November 1963, the Gemini Management Panel* decided that the program's current schedule needed rethinking. The key question was just how much spacecraft and booster testing had to be repeated at the Cape to ensure a successful mission. Two panel members, MSC Gemini Program Manager Charles Mathews and  Space Systems Division launch vehicle chief Richard Dineen, set up an ad hoc study of work plans and schedules aimed at seeing men in orbit via Gemini before the end of 1964. Mathews reported the findings to the panel at its next meeting, 13 December 1963. Gemini 3 could he launched in November 1964 by cutting down spacecraft testing at the Cape that merely repeated work already performed in St. Louis and by better integrating the entire checkout effort. Launch-vehicle testing was already fairly well meshed between Baltimore and the Cape and needed only to be smoothed out.70
Spacecraft checkout procedures were altered sharply "to get a complete working spacecraft out of the McDonnell plant." All testing in St. Louis, along with whatever manufacturing tasks were left after systems testing began, was to be modeled on Cape practice. This meant that the McDonnell test crew had to be retrained. John J. Williams, Assistant Manager for Gemini of MSC Florida Operations,** took a Launch Preparation Group of 200 people, drawn from both NASA and McDonnell, to spend nearly nine months in St. Louis. They thoroughly revamped the testing process, training the St. Louis crew and actually checking out the second and third Gemini spacecraft. About half the group returned to the Cape with Spacecraft 2 in September 1964, and the rest stayed until Spacecraft 3 was ready in January 1965. The retrained McDonnell crew took over when Spacecraft 4 began systems testing. Basic to the new process was cutting down on repeated testing. Once a subsystem had been tested, it would take its proper place in the spacecraft and stay there. No longer was the spacecraft to be taken apart after it reached the Cape, tested, and put together again. Systems were to be rechecked, of course, but only as part of the complete spacecraft, not as individual pieces.71
The booster offered fewer problems in meeting Gemini schedules. Aside from efforts to speed up work on GLV-1, already at the Cape, the only major step was to strike flight readiness firing from the test program planned for the first three launch vehicles. With spacecraft checkout streamlined and booster testing smoothed out, GPO looked forward to getting back in step with the April 1963 schedule, even though the first flight was now going to be about three months late. The eight months that had been allowed between the first two flights was cut to five, with Gemini 2 only a month behind schedule, in August instead of July 1964. By then keeping to the three months between later flights, the first manned mission could be launched in November, a month late, but still in 1964.72
* MSC Director Robert Gilruth had formed the panel in October 1962 to deal with managerial and technical problems. It brought together the heads of the organization in charge of Gemini - from NASA, the Air Force, and major contractors.
** On 30 March 1964, Gilruth announced that the Preflight Operations Division had become an autonomous unit known as MSC Florida Operations. Directed by G. Merritt Preston, the group would perform much the same duties as it had in Mercury. The only major change would be the participation in testing at McDonnell.
A Taste of Success
 While Gemini's first spacecraft and launch vehicle were moving toward their mating on complex 19 at Cape Kennedy, the Gemini Program Office itself was coping with another kind of move. The permanent home of the Manned Spacecraft Center at Clear Lake, though not quite finished, was ready to be occupied. GPO began shifting its desks from the old Veterans Administration building in downtown Houston to the new campus-like setting near Clear Lake on 6 March 1964. Shortly after the transfer had been completed, Program Manager Charles Mathews announced a reorganization of GPO. Major changes reflected the growing stress on schedules and testing as Project Gemini poised on the verge of its first flight. Project Administration changed its name to Program Control.* Scott H. Simpkinson left Mathews' staff to take charge of a new Test Operations Office dealing with reliability and quality assurance as well as test planning and evaluation.** Launch Vehicle Integration became Vehicles and Missions, divided into vehicle development and mission planning offices, plus a  new integration office to keep tabs on spacecraft/launch vehicle and spacecraft/target interfaces.*** The Spacecraft Management Office simply changed its name to the Spacecraft Office.**** The Houston-based strength of the program office had now reached 117; GPO also maintained representatives at Martin in Baltimore and Lockheed in Sunnyvale, California, as well as resident manager's offices at McDonnell in St. Louis and Kennedy Space Center at the Cape.# This was the organization that, with only minor changes, saw Project Gemini through to its end.1 Before that happy end, however, there was the more immediate matter of Gemini-Titan 1.
The First Flight
By 3 March 1964, spacecraft and booster were at last together on launch complex 19 at Cape Kennedy. The series of tests that showed all booster systems were working had just been completed, and the spacecraft had been hung on a tripod in the "white room" atop the launch vehicle erector. This room, with its four levels and 4.5-tonne  (5-ton) crane to hoist the spacecraft, was sealed off from the outside world and maintained at a constant temperature of 295 kelvins (72°F) and a constant relative humidity of 50 percent, to provide a controlled environment for the spacecraft and the upper stage of the booster. Next to the erector was an umbilical tower 31 meters high. Its seven booms supported 31 cables and lines to spacecraft and booster, feeding electrical power, propellants, and other needs until the moment of launch. Gemini-Titan I was scheduled to lift off on 28 March 1964.2
A premate systems test on 4 March confirmed the spacecraft ready for mating the next day, when the spacecraft-to-launch-vehicle adapter would be bolted to the booster's upper stage. The effort was delayed briefly when a McDonnell worker dropped his wrench on the dome of the oxidizer tank just below the spacecraft. A plastic sheet protected the dome, but the impact produced a scratch 0.95 centimeter (0.375 inch) long and 0.0038 centimeter (0.0015 inch) deep in the steel surface, just 0.16 centimeter (0.64 inch) thick at the point of impact. The area was burnished to the depth of the scratch and tested to confirm that the metal was still solid.3
After the spacecraft and launch vehicle had been mechanically mated, they also had to be connected electrically. But first the booster's status had to be checked in a combined systems test. That was slated for Sunday, 8 March, to be followed by three electronic-electrical interference tests between 9 and 13 March, to make sure there was no serious incompatibility. Minor problems delayed the booster combined systems test until Tuesday, and interference testing did not start until Thursday, 12 March.4
The first try at an interference test had to be scrubbed, and that cost another four days. On Monday, 16 March, however, the test went off without any trouble, prompting the crew to run through the second test at once. The attempt went awry through a procedural error. Another try, on Thursday, 19 March, brought bad news. Some amplifiers in the circuits that controlled the boosters tandem actuators (which shifted the engines to alter flight path) showed noisy outputs. A special dry run the next day produced the same problem, and the third interference test had to wait until the trouble was resolved. There was some question about how that was to be done, which was settled on Tuesday 24 March, when Martin troubleshooters pinpointed the problem - in the test equipment. Another test, on Wednesday, confirmed the finding. A conference that evening concluded that the data from the dry run the previous Friday met the intent, if not the precise format, of interference testing. The test equipment was removed that night.5
But the tests had taken almost two weeks longer than planned, forcing the launch to be postponed to 7 April 1964. Things now began to move more smoothly. On Friday, 27 March, a combined systems  test and simulated flight produced no serious problems.6 The following Tuesday, 31 March, all the nonflight parts that GLV-1 had carried to the Cape were replaced and Pogo gear installed. GLV-1 was scheduled to have its tanks filled with propellants that night as part of a complete countdown exercise, the wet mock simulated launch.
At 9 p.m., as shift workers were clearing the area for the start of tanking, someone saw smoke pouring from a switch at the pad. A burnt-out transformer and switch motor forced the test to be suspended, since there were no spares on hand and the switch performed a crucial function. It automatically transferred the launch complex to auxiliary power if commercial power failed. Safety demanded that the launch area be deluged with water in case of propellant leak; a power loss would leave that system inoperable for about 30 minutes if the automatic switch were not working. Workmen found a spare transformer at 1:18 Wednesday morning and installed it, but a new motor was harder to locate. One was finally borrowed from the blockhouse since that system could be run by hand.7 But another day had been lost.
Propellant loading resumed just before 10 Wednesday night and finished four hours later. The countdown began at 5 o'clock Thursday morning, but now came weather trouble. The Cape was under an "atmospheric inversion," a blanket of warm air above cooler air near the ground, which would block the upward dissipation of toxic fumes in case of accident. The count was held from 7 to 8:30, when the inversion started to break up. Ground crews then removed the propellant lines leading to the booster tanks and the count resumed. It followed its normal course until three minutes before launch, T-3, when a minor problem (quickly corrected) required the count to be recycled to T-5. Five minutes later, at half-past noon, the count reached T-0, the moment when the booster's first-stage engine would have ignited in a real launch. The test was a complete success, free of spacecraft problems and marred only by a minor procedural error in the launch vehicle countdown. After a vibration test of GLV-1, the tanks were drained of propellants, a five-hour process finished at midnight.8
The Spacecraft Flight Readiness Review Board* convened Friday afternoon, 3 April, in the conference room of the Engineering and Operations Building, headquarters for MSC's Florida Operations. A check of items left open from the preflight review of 18-19 February  showed that everything had been taken care of except a circuit breaker not yet fully qualified. It was close enough, however, for McDonnell to certify it flightworthy, a judgment the board shared. Only two new problems had cropped up since the earlier review, both easily corrected. The board judged all systems ready for flight, pending the outcome of the final systems test, a simulated flight scheduled for 5 April. When the simulated flight went off without a hitch on Sunday, Spacecraft 1 was ready for its mission.9
Flight readiness of the launch vehicle was reviewed Saturday afternoon. The Air Force reported two problems, one of which turned out to be nonexistent. The other involved a missing report of the results of an analysis of a failure in the secondary autopilot. The report was still absent on the eve of flight, but a phone call confirmed that the problem had been analyzed. After the simulated flight on Sunday, Walter Williams convened the Mission Review Board. Spokesmen for every group involved in the mission reported everything ready - "all systems 'go.'" At noon, Williams announced that NASA was "proceeding toward a launch not earlier than 11:00 a.m. Wednesday, April 8."10
The final decision for launch came on Tuesday morning. At 7:30, 7 April, SSD's Status Review Team for GLV-1 met, took a last look at the launch vehicle, and agreed it was ready to go. That recommendation was passed on to the Flight Safety Review Board at 9:00 a.m. The board approved GLV-1 for flight and committed it to launch, with lift-off set for 11 the next morning.11
Preparations for the final countdown were already under way. The first part of the planned 390-minute split countdown started before dawn on Tuesday. That 60-minute segment ended at 5 a.m., when the count was held for 23½ hours to prepare the spacecraft for final countdown, install and hook up pyrotechnics, run some launch vehicle tests, and load propellants. GLV-1's tanks were topped off at 4:10 Wednesday morning, with about 75 people from Martin, the Air Force, Aerojet-General, and Aerospace on hand. Thirty systems experts from McDonnell and MSC arrived at the blockhouse at 4:30.The hold ended right on time, an hour later, and final countdown began at 6 a.m. or T-300. No flaw marred the entire five-hour process.
One second after 11 o'clock Wednesday morning, 8 April 1964, the booster's first-stage engine ignited. Of this one-second discrepancy, a joking Williams later remarked to a roomful of reporters, "There must be something wrong with the range clock." Four seconds later, the 136-tonne (156-ton) vehicle lifted from the pad on that curiously lambent flame so distinctive of Titan II's hypergolic propellants.12
Within moments, Gemini-Titan 1 vanished into the hot Florida sky, beyond reach of human senses but not electronic sensors. Telemetered data flowed back to mission controllers at the Cape, telling  them that the launch was as nearly perfect as it looked. Two and a half minutes after liftoff, the 118 tonnes (130 tons) of propellants in its first stage exhausted after driving Gemini-Titan 1 64 kilometers high and 91 kilometers downrange, GLV-1's first-stage engines cut off. The second-stage engine flared into life, and the four bolts that had held the two stages together exploded as they were designed to, cutting the spent first stage loose from the still-accelerating second stage and spacecraft. Five and a half minutes after launch, the second- stage motor stopped, its 27 tonnes (30 tons) of propellants gone. Now 1,000 kilometers downrange and 160 kilometers high, coasting at a speed of 7,888 meters (25,879 feet) per second, Gemini Spacecraft 1, with the second stage of GLV-1 still attached, was in orbit.13
Everything had gone beautifully. Purists might cavil at an excess 7 meters (24 feet) per second launch-vehicle speed that propelled the spacecraft into an orbit reaching out 320 kilometers instead of the programmed 299 kilometers. But they could scarcely deny the handsome achievement of the main goals - proving that the booster could do its job and that combined with the spacecraft its structure was sound. "There's no question these objectives were met," Walter Williams observed to the press shortly after launch.** The nearly flawless performance of the launch vehicle elated its sponsors, prompting one of them, Major General Ben Funk of SSD, to call it "just completely a storybook sort of flight."14
The mission of Gemini-Titan 1 was much shorter than its actual trip. Only the first three orbits were part of the flight plan. When Spacecraft 1 passed over Cape Kennedy for the third time, about 4 hours and 50 minutes after launch, the first Gemini flight came to a formal close. The spacecraft had been expected to orbit Earth for three and a half days. Because of its slightly higher than planned orbit, it actually stayed up for nearly four days. During that time, the Manned Space Flight Network,*** a round-the- world system of tracking stations controlled from Goddard Space Flight Center in Maryland, followed the vehicle by radar. On Sunday, 12 April, during its 64th pass, the steadily slowing spacecraft plunged back into the atmosphere, ending its career in flames over the South Atlantic, midway between South America and Africa.15
 NASA Associate Administrator Robert Seamans commended "the Air Force for its most successful Launch Vehicle Program."16 So fine a performance of the first mission augured well for those to follow and surely enhanced the prospect that Gemini astronauts would be in orbit before the end of the year. But the glow of accomplishment soon faded before the hard work yet to be done. While the launch vehicle was now qualified for manned missions, the spacecraft was not. Despite the gratifying success of Gemini-Titan 1, and some real progress on troublesome spacecraft systems, there was no time to rest on laurels. The target vehicle for Gemini's later missions was still a very large question mark, and Gemini's chronic money woes were far from settled. For all of that, Gemini's future in the spring of 1964 must have looked much brighter than it had only a few months earlier.
Postscripts and Prospects
So bright, in fact, did the future seem that the long dormant idea of using the Gemini spacecraft for a lunar mission stirred again. George Mueller, NASA's Associate Administrator for Manned Space Flight, had some reason to be concerned about the outlook for Project Apollo in the spring of 1964. Only a few months earlier, plans for manned flights using Saturn I had been canceled, leaving Gemini as the only possible system for manned orbital flights during the next two years or more. Mueller wanted to know if a Gemini lunar mission could be flown. If it could, then a contingency plan was to be prepared for a Gemini flight around the Moon in case Apollo suffered a serious setback. A review of past studies strongly suggested that the idea was feasible and that McDonnell should be asked to conduct a more detailed study.* 17
But that was not to be. During a tour of the plant in Louisiana where Saturn rockets were built, Wernher von Braun, Director of Marshall Space Flight Center, told a journalist that Gemini might be able to fly around the Moon, but only as "a possible project to salvage this country's prestige if the manned lunar goal proves impossible." Whether this was intended to squelch an Apollo rival, the effect might have been predicted. The same factors that had blocked the idea before still held. NASA had too much invested in Apollo - too much money, time, and prestige - to really think about Gemini to the Moon. Funds, in any case, were tight. On 8 June, Seamans told Mueller there would be no money for study contracts. "Any circumlunar mission  studies relating to the use of Gemini will be confined to in-house study efforts."** 18
But that was never more than a side issue. In mid-1964, the first task was still Project Gemini, however attractive the prospects of a more ambitious program might seem. The outstanding performance of Gemini-Titan 1 and the qualification of the Gemini launch vehicle were most cheering portents. When the Gemini Management Panel met a week after the mission, on 15 April, a comfortable optimism suffused the group. The current work schedule called for the second flight toward the end of August and the third in mid-November, with almost a four-week cushion in each instance to handle unforeseen problems.19
This bright outlook darkened in the late summer before a series of natural disasters. First lightning, then hurricanes, conspired to abuse the second Gemini launch vehicle on complex 19 at Cape Kennedy and to delay its flight long past the scheduled time. Even had the weather been perfect, however, McDonnell's difficulties in getting Spacecraft 2 ready to fly might have compromised the schedule.
Late deliveries - notably of thruster systems from Rocketdyne and fuel-cell stacks from General Electric - had slowed construction of the spacecraft during 1963. Parts had failed tests that had to be passed before they could be installed in the spacecraft; modifications meant further delays. Spacecraft 2 could not begin its systems tests until 13 January 1964.20
The Spacecraft 2 Design Engineering Inspection (DEI), earlier set for November 1963, had been postponed in the face of these delays until February 1964. MSC formed a permanent DEI board 31 January 1964 to make sure that the spacecraft as a whole and each of its parts would do what they were intended to that the spacecraft could, in fact, be expected to achieve its assigned objectives. Normally, the DEI for each spacecraft would fall between the end of manufacturing and the start of systems testing, but the DEI for Spacecraft 2 was a little late. The nine-member board convened at the McDonnell plant on 12 February.*** Also present for the two-day meeting were 50 experts from  GPO and McDonnell, as well as another 50 observers from other MSC offices, NASA Headquarters, and the Air Force. The board looked over the hardware and studied the records to see that each part either matched design specifications or was the subject of a proper waiver. A long list of minor discrepancies ended up as 22 mandatory changes, 4 conditional, and 10 to be studied.21
The first phase of spacecraft systems tests went slowly, as problem after problem turned up; troubleshooting them, working out the required changes, and testing the results all took time, adding to the delays. By mid-April 1964, Spacecraft 2 had become the "pacing item" for the second Gemini mission, a dubious honor held by the launch vehicle before the first flight. Getting the spacecraft ready was now the crucial factor in meeting the scheduled launch date.22 This was not altogether a surprise. Spacecraft 1 had been little more than an instrumented shell, but GLV-1 had been a launch vehicle in every sense of the term. The Martin crews working on GLV-2 were going over ground they had already surveyed, but Spacecraft 2 was the first fully equipped ship to go through the McDonnell plant and its slow progress reflected its novel status.
After the modules of the spacecraft had been mated, the second phase of systems tests began, on 3 July. Further problems hampered testing into the next month.23 Whatever delay might have resulted, however, became purely academic after mid-August, when Florida weather dealt the first of a series of time-consuming blows to GLV-2.
GLV-2 and the Elements
While spacecraft testing floundered past snag after snag, GLV-2 had been moving briskly through its test program despite some rough spots. At the outset, the second-stage oxidizer tank was found defective, and a new tank had to be built. Since the first-stage tanks were not yet ready, the delay was inconsequential. Martin-Baltimore received all four tanks from Denver on 12 July 1963. Engines were late in arriving from Aerojet-General, but testing went ahead with nonflight first-stage engines. By the end of January 1964, GLV-2 had completed its horizontal test program. Early the next month it was standing in the Vertical Test Facility; and, after two weeks of modification work, functional verification tests of subsystems began on 21 February.24
GLV-2 finished these tests by 13 April, in roughly two thirds the  time taken by the first booster. Another week saw it through electrical-electronic interference tests and three preliminary combined systems acceptance tests (CSAT), an effort that had cost GLV-1 over a month. The formal CSAT was run on 22 April with no trouble, and the results were approved by the Vehicle Acceptance Team the following week. The dummy engines still had to be replaced, which took a month. By mid-June, GLV-2 had been inspected and formally accepted for the Gemini program. Since spacecraft work was lagging, the booster's transfer to the Cape was postponed so Martin crews in Baltimore could complete some of the modifications that would otherwise have been made by the Martin-Canaveral team.25
Workmen loaded the booster aboard an Air Force C-133B aircraft on 10 July 1964. By noon the next day, both stages had been unloaded and secured. Working a two-shift, five-day week, Martin's Cape crew expected to have GLV-2 ready for Spacecraft by mid-August. Everything proceeded routinely through July and into August, with only minor problems causing small delays. This was of no moment, since the spacecraft was still in St. Louis. Its shipment, scheduled for 1 August, had been postponed for three weeks; it could not now reach complex 19 before the first week in September. The Martin crew nevertheless prepared for the final test of the booster before its mating with the spacecraft and were almost through by 17 August.26
But that Monday a severe thunderstorm pounded Cape Kennedy. About half an hour before midnight, lightning struck complex 19. There was no visible damage to the blockhouse, erector, or rocket, but that proved nothing about the status of the electrical and electronic gear. Whether GLV-2 was fit to fly was a real question. NASA labeled the event an "electromagnetic incident" and demanded a thorough investigation. Inspectors from Martin, Aerospace, and the 6555th Aerospace Test Wing found no signs of any physical damage, but they did locate a number of failed parts, mostly in the ground support equipment. This suggested that the complex had not taken a direct hit but rather had suffered the electromagnetic effects, or induced static charges, of a nearby lightning strike. A test order issued on 20 August set the task: To "re-establish confidence in all [launch vehicle], AGE, . . . and Facility Systems, and to determine that all degraded equipment is replaced and appropriate reverification tests are successfully completed." The next day, Gemini manager Mathews flew in from Houston for an "Incident Status Meeting." A three-man steering committee was appointed to oversee the efforts of Air Force, Aerospace, and Martin work crews.* 27
 Two weeks seemed ample to put things back in order. Most subsystems would have to be retested, and all booster systems, test equipment, and facilities would have to be checked out. Any equipment that might have been affected had to be repaired or replaced. After some consultation, NASA agreed that no airborne units with semiconductors ought to be retained. Once new units were installed, testing could begin again as though the vehicle had just arrived at the Cape.28
Before the work was finished, however, Hurricane Cleo belied the forecasts and brushed the Cape on Thursday, 27 August. The Martin crew had time to get the second stage down and under cover, but the first stage remained upright, lashed in place with the erector lowered. Cleo's winds were well below the upper limit that the booster was designed to withstand. With the weather still bad on Friday, the second stage stayed in storage over the weekend. On Monday, the Air Force was getting ready to launch its first Titan IIIA from the next complex, which hampered work on pad 19 for most of the day. By 3 o'clock the next morning, however, the Martin crew had stage II back in place atop the first stage. Further work was delayed by the countdown on the nearby pad, which ended at 10 a.m., Tuesday, when the Titan IIIA blasted off. GLV-2's repeat of subsystems functional verification tests began on Thursday, 3 September.29
By then, MSC was just about ready to give up on GLV-2. The Center proposed dropping it from the program and moving each of the other launch vehicles up a notch. GLV-3 would launch Spacecraft 2, and the flight program would lose one mission. The Air Force, strongly seconded by the launch vehicle contractors, urged NASA to stick with GLV-2. A thorough review of the effects of both lightning and hurricane, the measures taken to counter them, and the test results had convinced the Air Force and its contractors that GLV-2 was still as sound as ever. Their case was solid enough to convert the skeptics. An Air Force spokesman concluded: "Based on technical considerations, Martin-Marietta Corporation, Aerojet-General Corporation, [and] Aerospace Corporation recommend fly GLV-2. In addition, SSD has reviewed cost and schedule considerations and concludes fly GLV-2." NASA agreed, and the work went on.30
Testing had scarcely begun, however, before Nature intervened a third time. Cleo had struck only a glancing blow, but Hurricane Dora was aiming straight for the Cape. As Dora approached on 8 September, Martin workers raced to get both stages of GLV-2 down and safely under cover in a hangar. Wednesday was a day of waiting as Dora passed by. On Thursday, Dora was no longer a threat, but Hurricane Ethel was heading for the Cape and due to arrive by the weekend. GLV-2 stayed under wraps. By Monday, 14 September, the danger was past, and GLV-2 was back in place before the end of the day. The rest of the week was largely given over to replacing semiconductor  units and to a thorough inspection of booster and launch complex. Testing resumed after the weekend, on 21 September.31
That was the day Spacecraft 2 finally arrived at the Cape. The second phase of systems testing at St. Louis had lasted through August and into September, with frequent interruptions for the receipt and installation of a number of pieces of flight equipment.A simulated flight on 15 September completed testing. A Spacecraft Acceptance Review Board headed by Charles Mathews had already gone over the spacecraft to make sure it was ready for the final simulation.** The board met again on 17 September and decided that Spacecraft 2 was now ready for delivery. It was shipped to Florida the following Monday, 21 September.32
GLV-2's misfortunes during August and September 1964 forced NASA to forego its goal of a manned Gemini flight before the end of the year, as a rueful Mathews informed the Gemini Management Panel on 29 September. The second flight was now set for mid-November 1964, the third for the end of January 1965. There seemed no need to alter planned dates for the later Gemini missions, although the schedules would have to be tightened. Once again, Gemini's slowness was highlighted by a Russian first. On 12 October, the Soviet Union orbited Voskhod I. The three-man crew flew in a "shirtsleeve" environment (flight coveralls rather than space suits) and all remained in the spacecraft to a land landing (previously only Yuri Gagarin was believed to have stayed with his vehicle until it landed, the others leaving the spacecraft and coming down by parachute).33
GLV-2 began an expected two weeks of subsystems tests on 21 September, with the combined systems test that preceded spacecraft mating scheduled for 6 October. Spacecraft 2 should have taken only 11 working days in the hangar area before it joined the booster at the launch complex on 25 October. Once again, however, work on the booster went smoothly, but the spacecraft lagged. GLV-2 completed subsystems tests and the premate test on schedule. In another week the launch vehicle finished electrical-electronic interference tests, the last step before it was ready to receive the spacecraft. While the launch vehicle was being tested, so was the worldwide tracking network. From 9 to 16 October, Goddard and MSC put the tracking stations through their paces.*** 34
 The spacecraft, however, had yet to arrive at the pad. Work had gone well enough the first week, but trouble cropped up in getting the thrusters ready for a static firing test. After firing, the system had to be flushed and purged, another delay. By 10 October, Spacecraft 2 was already eight days behind schedule; it lost another two days while pyrotechnics were installed. Spacecraft 2 was ten days late when it reached complex 19 on Sunday, 18 October, and settled in the tripod in the white room an hour before noon.35
Attempts to run the spacecraft premate systems test brought new problems. As one was solved, another appeared; and it was 27 October before the test was complete. The final step before the spacecraft was joined to the launch vehicle was a premate simulated flight, run in two parts. Despite more than one discrepancy revealed by the test, the spacecraft was mechanically mated to its booster by noon Thursday, 5 November.
After the mating Martin conducted tanking exercises on the launch vehicle to check calibration, to see whether or not the launch crew could load the tanks accurately with the equipment on hand, and to train for launch loading. The Martin crew found some differences between the data gathered from calibration and what they thought they had loaded. This led to a series of tanking exercises throughout the program and set up "a new family of people, called the Wednesday Evening Tanking Society and the Thursday Evening Tanking Society - the WETS and the TETS."36
The troubled course of testing and checkout now smoothed. Over the next month, any problems that showed up were handled quickly, as Gemini 2 ticked off the milestones on its way to a 9 December launch: electrical interface integrated validation, 9 November; joint guidance and control test, 12 November; joint combined systems test after electrical mating, 17 November; wet mock simulated launch, 24 November; spacecraft final systems test, 28 November; simulated flight test, 3 December; and launch precount, 7 December.37
Setback and Success
Loading propellants aboard GLV-2 began in earnest on Tuesday, 8 December, an hour before midnight and finished shortly after three o'clock in the morning. The final countdown started an hour later. It went smoothly, though not quite so smoothly as the first Gemini countdown - there were three holds for a total of 41 minutes.  The count reached zero at 11:41 Wednesday morning, and the first-stage engines ignited. One second later, a signal from the master operations control set shut down the engine. Flight controllers in the Cape control center observed that the launch vehicle had lost hydraulic pressure in its primary control system and had switched over from primary to secondary guidance and control. Within the blockhouse, technicians began to power down the spacecraft and, at three minutes before noon, Flight Director Christopher Kraft officially canceled the flight.38
The proximate cause of the shutdown was the command from the master operations control set, an automatic response to an automatic function - the switchover from primary to secondary flight control during the 3.2 seconds between ignition and liftoff. After the engines ignited, the launch vehicle remained bolted to the stand until thrust built up to 70 percent of maximum. During that time, a switchover in the control system was an automatic shutdown order. The GLV-2 switchover followed automatically when the booster's malfunction detection system sensed the pressure drop in the primary hydraulic system. GLV-2, in other words, spotted its own hydraulic failure, responded by switching over to its secondary system, and then, because it was still on the ground, commanded its engine to shut off.
Having saved itself, GLV-2 stood poised on the pad - a giant question mark. Why had its primary control system failed? The answer was quick in coming. Unexpectedly high pressure in one of the hydraulic lines had burst the aluminum housing of a servovalve, letting the hydraulic fluid leak out. This valve controlled one of the booster's four tandem actuators, the devices that moved the thrust chambers to steer the vehicle in flight. Why the valve housing had failed was a lesson in the folly of unneeded "improvement." At some time during development, someone had decided that the walls of the housing were twice as thick as they needed to be; a third of a centimeter of aluminum was ample to meet design pressures. No one, however, thought to test the actual pressure the housing would have to withstand, nor was any impulse test, as such, included in system qualification. More likely than not, one or another Titan II had suffered the same sort of hard start, but the stouter housings that remained standard in the missile could survive such a pulse while the lighter structural shell in the Gemini booster could not.39
When GLV-2 shut down, Spacecraft 2 posed something of a problem. Launch crews knew what to do with a ready-to-go booster, since they dealt with one after the mock launch that was a regular feature of launch vehicle checkout. There was no comparable background for the spacecraft, however, and that led to some hasty improvisation. Aside from its propellants, the spacecraft fairly bristled with pyrotechnic devices, all armed for flight. Should one of them explode, the results might be catastrophic.
 Draining the booster of propellants took first priority, so Wednesday had passed and Thursday was well along before the main part of spacecraft "safing" was complete. One particularly ticklish operation remained, however - pulling the pyrotechnics from the isolation valves that barred propellants from the spacecraft thrusters until time to fire. The problem was complicated by the fact that the explosive cartridge was not a replaceable unit, and the whole valve assembly had to come out. But this might allow propellants to reach the thrusters or to spill their highly noxious chemicals over the workers. The makeshift answer was to freeze the propellant lines. After one or two false starts - no one was quite sure how to do the freezing - copper tubing was wrapped around the lines (which were packed in dry ice), liquid nitrogen was run through the tubing, and the whole thing was sprayed with CO2.* That worked, and the valve assemblies were replaced over the weekend.40
There was really not much that could be done with the spacecraft over the next few weeks besides making sure it remained in flight status, and nothing much could be done with the launch vehicle until new actuators arrived.** A product of Moog Servocontrols, Inc., the tandem actuators had been taken back to the vendor's plant in East Aurora, New York, for extensive tests. Then the actuators had gone to Martin-Baltimore for further testing. The lightweight servovalves had to be redesigned. Work was further curtailed by the holidays. A messenger reached the Cape with the four new parts on 6 January 1965. They were installed at once and testing resumed, focused mainly on the flight control system. The new round of launch preparations went quickly; by Thursday, 14 January, the last major test was complete. Reviews of spacecraft and launch vehicle gave both a clean bill of health, and launch was set for 9 o'clock Tuesday morning, 19 January.41
The countdown began two hours past midnight. It was almost flawless, although it did produce one disappointment. Spacecraft 2 had been slated to carry six fuel-cell stacks of the old model P2B, left over after the design had been updated early in 1964. Despite their known defects, flight testing them with the reactant supply system seemed like a good idea, but only on a "non-interference with flight" basis and with a dummy load, since electrical power would actually be supplied by battery. The six stacks assigned to Spacecraft 2 had behaved erratically  since they were first installed in St. Louis. When they acted up during the abortive countdown on 9 December and threatened to delay the launch, they were scratched from the mission. Only one stack proved to be still operable; it was activated on 18 December, then shut off and left alone until the next launch attempt. An hour and a half after the countdown started on 19 January, hydrogen intake to the stack was blocked by a stuck valve. Two hours of work left troubleshooters faced with breaking the spacecraft wiring to correct the problem. Since that would have meant a hold in the countdown, the attempt to activate the stack was called off, and the fuel cells were not operated on Gemini 2.42 Aside from the fuel-cell problem, the countdown produced only the most minor anomalies an preplanned two-minute hold.
At four minutes after 9 Tuesday morning, Gemini 2 began the last unmanned flight in the Gemini program. GLV-2 hurled the spacecraft 3,430 kilometers across the South Atlantic through an arc that peaked 160 kilometers above the ocean's surface. The spacecraft endured the most severe heating Gemini was ever likely to meet as it plunged back into the atmosphere, its heat protection proved, its structural integrity uncompromised, and all systems working. It dropped into the South Atlantic on its parachute about 18 minutes after launch, bobbing in the water for an hour and a half until it was picked up by the U.S. Navy's aircraft carrier Lake Champlain.43
Some small question marks dotted the mission, but overall it looked quite good. The postflight news conference was a scene of quiet jubilation, with pats on the back for everyone involved. Nothing earth-shaking turned up in the detailed study of the recovered spacecraft - only minor scratches, chars, corrosion from exposure to sea water, just about what might have been expected - nothing that would in any way militate against the forthcoming launch of Gemini 3, the first to carry men aloft.44
Down to the Wire
While most eyes had been focused on Gemini 2 at Cape Kennedy, work on still-to-be-resolved development problems continued elsewhere. Two spacecraft systems indispensable for Gemini's first manned mission - thrusters and ejection seats - remained question marks through most of 1964, and a third - fuel cells - though not slated for Gemini 3, was as yet unqualified. What may have been the largest question of all centered on the Gemini Agena, which throughout 1964 fell further behind schedule.
In April 1964, Rocketdyne seemed at last to have solved its major problems in developing workable thrusters for Gemini, but misgivings persisted. When the Jet Propulsion Laboratory approached Rocketdyne about developing a small engine for the Surveyor spacecraft, Mathews protested.  He argued that the company was still a year away from having the Gemini orbital attitude and maneuvering system and reentry control system on a sound footing, and that the main reason the work had improved was the belief that it would get no more NASA small-engine contracts until Gemini work was almost done. Workloads in the California plant were heavy, as shown by the large demands for overtime, and the original $30-million contract had ballooned to over $74 million, of which almost $36 million was an overrun.
Despite the enormous infusion of effort and money, Rocketdyne had failed to maintain schedules and deliveries. Engines for Spacecraft 2, for example, due in February 1963, arrived on in January 1964, and "the delivered products leave much to be desired." Mathews thought it "quite evident that all three interested parties, the Gemini Program Office, the Surveyor Program, and Rocketdyne, will benefit through the selection of a vendor other than Rocketdyne," since the added work could only hamper Gemini without contributing much to Surveyor.45
This concern was echoed by manned space flight chief George Mueller;* in a memorandum to his counterpart in the Office of Space Sciences, which had charge of the Surveyor program, he urged that Rocketdyne be denied the contract. MSC Director Gilruth also acted, setting up a special committee to survey Rocketdyne's Gemini program. After hearing some harsh committee findings on 5 August 1964, Rocketdyne's president promised that whatever NASA wanted would be done. Gilruth sent him a long list of recommendations a week later. Some changes were already under way even while the committee was meeting, and more followed, including a reorganization of Rocketdyne's Space Engine Division.46
Among the recommendations was a full-scale NASA audit of Rocketdyne's business management practices and Space Engine Division operations. It was a large undertaking, and a report was not ready until April 1965. Its findings revealed a badly managed program. Having "grossly underestimated the magnitude and complexities" of its Gemini subcontract, Rocketdyne had been slow to set up a sound organization. As a result, budgets were poorly controlled "and operations were inefficient," producing "significant cost overruns and delays." Not only had outright overruns very nearly doubled the cost of the program, but, of the 358 engines that should have been delivered by November 1964 under the original contract terms, only 167 had actually been received. Frequent personnel changes at top levels reflected the  program's weak management, as did the company's complete inability to provide records showing the reasons for technical problems, what action they prompted, or what impact each problem had on costs and deliveries. The auditors recommended "that Rocketdyne's fee under the Gemini subcontract be adjusted."47
When this report was released in the spring of 1965, the worst was already over. Rocketdyne's performance had, in fact, begun to improve markedly in mid-1964, although as late as October Gilruth still thought an alternative source for thrusters might be a good idea. McDonnell received the first long-duration attitude maneuvering thrusters in October 1964, just five months after the new design had been released to production. By the time the audit report was issued, both the attitude and reentry control systems had been fully qualified in their Spacecraft 3 version. How greatly things had changed was shown most clearly when the long-life thrusters, not expected to be ready before Spacecraft 5, were actually installed in Spacecraft 4.48
Qualification of the Gemini escape system, like that of the spacecraft rocket systems, was essential before astronauts could be committed to a mission. Rapid progress early in 1964, which saw the development test program concluded, augured well, as did a good start on dynamic proof-testing. A preliminary sled-ejection test on 4 June 1964, to see if hatches and hatch actuators functioned properly under abort conditions, went off without a hitch. Qualification testing began on 1 July with a sled run to simulate conditions of maximum dynamic pressure after an abort during the powered phase of launch vehicle flight. Once again, everything worked.49
The same problem that had delayed development testing, one that had little to do with seat design, again brought the test program to a halt. Some of the pyrotechnic devices on which escape-system operation depended failed to arrive. The result was a four-month gap after the July run. In the meantime, NASA had decided to go ahead with a new test series. Sled and tower tests had been the only dynamic simulations planned for the system. Neither, however, could show the system working through its entire sequence as in a high-altitude abort. That became the purpose of a plan to eject the system from a high-flying F-106, worked out at a meeting between NASA, McDonnell, Weber Aircraft (the maker of the system), and the 6511th Test Group at El Centro, California, on 12 June. The first test, intended merely to show that the seat would work with the airplane, was set for September with the F-106 on the ground. Two flights, using production escape systems, were to follow, with the whole series to be finished in a month. Once again, however, lack of pyrotechnics caused delays. Enterprising engineers borrowed some from the ejection seat in North American's paraglider tow test vehicle, enabling them to run the ground test on 15 October. But nothing more could be done for three months.50
 Enough pyrotechnics were on hand for another sled run on 5 November, which revealed a flaw in seat design. An instant after it had been ejected, one of the seats suffered a structural failure of its armrest and side panel that stopped the separation and recovery sequence. Seat and dummy smashed into the ground, strewing wreckage for 140 meters along the track. The hard question now was whether or not the test program had to be revised. The answer was no, provided the reworked seat structure performed well in a test approximating the most severe conditions for which the system was designed. In a sled run on 11 December, it did just that. The system came through with flying colors, bringing that part of the qualification program to an end.51
It was perhaps just as well that Gemini 2 had been so long delayed. By the end of 1964, only one of the four major parts of escape-system qualification had been completed. Still to be conducted were simulated off-the-pad ejection (Sope), personnel parachute, and high altitude ejection tests. All three resumed in January 1965, when pyrotechnics at last began to arrive.
 First to get under way, on 11 January, was parachute testing. Four dummy drops and 12 live jumps from low altitudes over the next month turned up only minor problems. High-altitude testing followed.52 In the meantime, On 16 January (a year and a half after Sope development tests ended) Sope qualification testing began. Shortage of pyrotechnics had again been the chief culprit in the delay. The first try failed. One seat worked, but the catapult on the right-hand seat fired too soon and exploded when the seat jammed against the still partly closed hatch. Almost a month passed while all hatch actuators were modified and the results checked out. Both the redesigned actuators and the escape system proved themselves in flawless Sope tests on 12 February and 6 March.53
High-altitude ejection was the last test program to resume but the first to finish. Nothing went wrong in the first test, an ejection at 4,780 meters at mach 0.65 on 28 January. Two weeks later, however, in a test at 12,000 meters at mach 1.7, the aneroid device that was supposed to trigger parachute deployment failed, although everything else worked. That device also failed to deploy the ballute on 17 February, in the first high-altitude live jump, forcing McDonnell and Weber engineers to redesign the aneroid-controlled firing mechanism. Although the aircraft ejection test did not have to be repeated, since being ejected from the F-106 did not cause the failure, the parachute test program did have to be revised. That meant an extra 10 dummy drops and 5 live jumps, which began on 2 March. The final jump, on 13 March, qualified the personnel parachute system and completed the qualification of the Gemini escape system as a whole.54 And not a moment too soon. The launch of the third Gemini mission, the first to carry a human cargo, was only days away.
The demand for fuel cells was not so pressing in late 1964 as for thrusters and ejection seats, since Spacecraft 3 and 4 were already being converted to battery power as a result of earlier problems. GE's redesigned fuel cell, the P3, had not at first lived up to its promise. Test sections performed erratically, their outputs tending to decay under load and their lives falling far short of requirements. This prompted NASA Headquarters to ask GPO on 10 July to provide a backup battery-power module in case fuel cells were not ready for the fifth Gemini mission. This was a drastic step, since Gemini 5 was slated for seven days; a battery installation to handle so long a mission meant a severe weight penalty and a narrow limit on what might be achieved during the flight. One of the main reasons for putting fuel cells in Gemini had been to ease constraints on such lengthy missions. GPO directed McDonnell to work out with Eagle-Picher, the battery subcontractor, a plan for a backup system.55
Early in August, GPO enlarged the scope of the study, asking McDonnell to cover the effects of substituting batteries for fuel cells in  all two-day rendezvous missions, of using Agena-supplied power in a combined long-duration and rendezvous mission, and of such changes on the fuel-cell program itself. McDonnell found the feat possible but costly, especially in weight. At a meeting on 14 August, Mathews and Burke decided to provide Spacecraft 5 with a combined system of batteries for the peak loads and fuel cells for basic power needs. If most of the experiments planned for the mission were discarded, Spacecraft 5 would only weigh 30 kilograms more with its battery-augmented system. NASA Headquarters sanctioned the change on 1 October.56
The combined system reflected GE's success, finally, in pinpointing the sources of fuel-cell shortcomings. GE engineers found that the life of test stacks declined as electrical load and the temperature of reactants rose. The greater the load - the amperage drawn from the stack - or the higher the inlet temperature, the shorter the stack's life. With a constant load, a change of only 17 kelvins (30°F) in reactant temperature - 313 kelvins (103°F) instead of 330 kelvins (133°F) - more than doubled stack life, from 125 to 290 hours. Holding the temperature constant and varying the load produced similar results. With batteries to handle peak loads, a major factor in truncated fuel-cell life might have been countered.57
These findings were based only on analysis of prior test data. Now GE revised its test program to see what effect lowered inlet temperatures and reduced loads actually had on test stacks. The results confirmed the premise. Two test units under a steady three-ampere load with reactants at 297 kelvins (75°F) lasted 1,100 and 800 hours. Further tests produced equally encouraging results at various levels of load and temperature under normal and abnormal conditions. All difficulties were not yet out of the way, but those that remained were largely matters of detail.58
Concern about "the rapidly rising costs of the General Electric fuel cell development program, coupled with the lagging development," persisted for a while; but, significantly, that worry was expressed in a memorandum never sent.59 The Gemini Program Office in Houston retained some doubts about fuel-cell prospects through the early fall of 1964, urging NASA Headquarters to allow batteries to replace fuel cells in Spacecraft 6 to ensure meeting the prime objective of that mission, rendezvous with an Agena target vehicle. Headquarters demurred until 6 November, but then granted the change.60
That decision stood, Spacecraft 6 eventually flying with battery power. In the meantime, however, the response of fuel-cell test units to lower temperatures was so marked during late summer and early fall as to convince both NASA and its contractors that the power system for Spacecraft 5 need not be augmented by batteries. That change was therefore canceled on 18 December 1964.  The Gemini fuel cell completed its basic qualification test program in May 1965, three months before it flew in the fifth Gemini mission.61
Agena was still further down the line, and its lagging pace showed no signs of speeding up during 1964. Project Gemini received its first Agena D at the end of April 1964, but nearly five months passed before it was converted into GATV-5001, the first Gemini Agena Target Vehicle. Lockheed completed that effort on 24 September and transferred the vehicle to the systems test complex, where cabling it up for preliminary vehicle systems tests began the next day. Not too surprisingly, testing did not run smoothly.
The hardest and most stubborn problems centered in Agena's command and communication (C&C) system - the electronic devices for tracking the vehicle, monitoring its subsystems, and passing commands to the vehicle in orbit. Because of Gemini's unique demand for rendezvous and docking, Lockheed had to design and prove a new C&C system for the Gemini Agena. The new design struck GPO as very good, a judgment confirmed by a special consultant group from Stanford Research Institute, which recommended only minor changes. During testing in October, however, parts of the system started acting up. Troubleshooting got GATV-5001 through its testing, but it seemed all too likely that the C&C system suffered from basic defects in its mechanical and electronic design. The question became, as Mathews later recalled, "Should we live with what we had, or should we back off and completely redesign the configuration?" When the problems persisted, the Air Force insisted on redesign, and Lockheed finally initiated a "Ten Point Plan for C&C Equipment" in February 1965.62
In the meantime, GATV-5001 had emerged from its preliminary tests in November 1964 and gone to Lockheed's Santa Cruz Test Base for a round of captive-firing tests. First, however, the target docking adapter had to be installed. This was the unit, built by McDonnell but carried aloft by Lockheed's Agena, to which the spacecraft would attach. When Lockheed workers hoisted the adapter into the test stand and tried to mate it with the Agena, they found it did not fit. After some struggling, they managed to get the two physically hooked together, but the wiring failed to match. The captive firing had to be postponed until January.63
The test on 20 January 1965 simulated a full two-week mission. It included related firings of both primary and secondary propulsion systems, with operational data transmitted to telemetry stations at the test site and at Lockheed's Sunnyvale plant. The propulsion systems worked well, but the C&C system again had problems. One part, the programmer time accumulator, jumped erratically, picking up almost eight extra weeks. Shipped back to Sunnyvale on 1 February, GATV-5001 lost three weeks while Lockheed tried to fix the capricious timer.  A makeshift fix allowed GATV-5001 to move on to the next phase, electromagnetic and radio-frequency interference tests, while engineers continued their efforts to diagnose and cure the jumping timer. By 23 February, when the interference tests began, GATV-5001 was more than a month behind schedule.64
Interference tests ended 9 March, but the vehicle stayed in the anechoic chamber for another week while Lockheed checked out its answer to the erratic timer and to a telemetry synchronization problem that had also cropped up. On 18 March, GATV-5001 moved to the systems test complex for a planned six days of "minor" modifications: filters were to be installed in the command controller (another part of the C&C system) and the forward auxiliary rack (which supported the target docking adapter and housed most of the C&C gear) was to be aligned. These two tasks proved to be more than minor. The first eventually required a complete redesign, the second extensive machining. The result was another lost month. By the end of March, GATV-5001 was 66 days behind schedule.65
Final systems testing got under way on 9 April and ended with a simulated flight on 6 May. On 27 May, the Air Force and Aerospace team found GATV-5001 formally unacceptable for Gemini, since FACI (first article configuration inspection) from 10 to 26 May had shown that it was not flightworthy. SSD took the vehicle anyway, but conditionally. Lockheed was expected to correct all defects; some were merely matters of paperwork, but others, like propulsion and C&C systems qualification, were major efforts. GATV-5001 was then flown to the Cape on 29 May, to be used as a development test vehicle.66
In the meantime, the first Atlas booster for Gemini had joined the program on 1 December in San Diego. It had then been shipped by truck to Cape Kennedy, a six-day trip. It was erected on complex 14 a week later, to help in checking out the launch pad and ground support equipment. Finished with that by 11 February, the Atlas was moved to a hangar, there to be modified and stored until GATV-5002 arrived.67
A Vote of Confidence
On Tuesday afternoon, just a few hours after the launch of Gemini 2, the program received another vote of confidence. Although the second launch had been long delayed, the nature of the delays in no way cast doubts on Gemini itself; NASA and its contractors decided that Gemini missions should he launched at two-month intervals, instead of the three-month cycle then planned.
In September 1964, the Air Force had not only convinced NASA that GLV-2 ought to fly, but also proposed to speed up the program by launching every two months. Although the Vertical Test Facility  at Martin-Baltimore had been designed to handle two launch vehicles at once, only one of these test cells was working. The Air Force suggested opening the second cell to speed up launch vehicle deliveries. SSD Commander Funk assured his Gemini colleagues that the Cape crew could handle launches only 60 days apart.
LeRoy E. Day, Headquarters Gemini Test Director, took charge of a task force to canvass spacecraft, launch vehicle, and target vehicle contractors about the practicality of the plan. A two-month study convinced Day and his group that it could be done. Although NASA's checkout crew at Cape Kennedy expressed a measure of skepticism based on their experiences in Project Mercury and the opening stages of Gemini, the Gemini Program Office had more faith. GPO had, in fact, been thinking of less time between launches when it imposed revised test and checkout procedures in St. Louis and at the Cape early in 1964. When Day presented his findings to Gemini's top echelon on 19 January 1965, they bought the plan and wanted it put into effect by the fifth mission. This vote of confidence in Gemini was founded on a technological judgment, and in that sense it was fully justified. Later events were to show that fitting astronaut training into the shorter schedule was a harder task, although it produced no problems that could not he surmounted.68
As 1965 dawned, Project Gemini had cleared most of the hurdles in its path. The past year had seen its last serious development problems overcome. Agena was perhaps not as far along as it should be, but there was plenty of talent at hand to put that in order. The repeated setbacks suffered by GLV-2 could only be seen as acts of God, not defects in technology. That could not be said of its failure on 9 December, but little more than a month of hard work was needed to put matters right. The second Gemini mission, on 19 January 1965, almost matched the first, on 8 April 1964, in the quality of performance. Gemini's spacecraft and launch vehicle had been proved. All that remained, the last hurdle, was sending men aloft. Although the publicly scheduled date for Gemini 3 was the second quarter of 1965, Charles Mathews told the Gemini Management Panel shortly after the flight of Gemini 2 that late March looked like a good bet.69
The Last Hurdle
 On 13 April 1964, the Monday after the flight of Gemini-Titan 1, the men and women of the press gathered in the auditorium at the Manned Spacecraft Center to learn who would be the first to fly the Gemini spacecraft. Robert Gilruth, Director of the Manned Spacecraft Center, introduced the four astronauts assigned to Gemini 3, the prime and the backup crews. Commander of the first team was Virgil I. Grissom - "Gus." His crewmate was John W. Young. Backing up the mission were Walter M. Schirra, Jr., and Thomas P. Stafford.1
The stocky, crew-cut Grissom, an Air Force major,* was an old-timer in NASA's manned space flight program, one of the original seven Mercury astronauts picked five years earlier. He already had a quarter of an hour of spacecraft flying time as passenger on the suborbital flight of Liberty Bell 7 in July 1961, Project Mercury's second manned mission, and would therefore be the world's first two-time space flyer. Young, his crewmate, was a younger man and a newer astronaut; a Navy lieutenant commander, he had been one of the nine pilots selected for the space program in September 1962. Schirra, like Grissom, was one of the Mercury seven. Born in 1923, he became the old man of the astronauts corps when John Glenn resigned early in 1964. In October 1962, Schirra had ridden Sigma 7 (the fifth manned Mercury spacecraft) through six orbits in the penultimate Mercury mission.  Stafford, Schirra's co-pilot in the backup crew, was an Air Force major who became an astronaut at the same time as Young.** 2
Gilruth voiced NASA's "high hopes of flying by the end of the year," 1964,3 leading America back into space after an 18-month hiatus. Those hopes foundered in the storms that lashed Cape Kennedy during the summer. When the launch vehicle for Gemini 2, after passing so smoothly through test and checkout, betrayed the mission in December, even Gemini's unmanned prelude remained unfinished at year's end. But the opening quarter of 1963 saw the success of Gemini 2 in January and then, scarcely two months later, Grissom and Young in orbit aboard "Molly Brown." With that, Project Gemini had clearly advanced a long step beyond Mercury and opened a new era in manned space flight.
The Men for Gemini 3
Within a week after they had been publicly assigned to the mission, the Gemini 3 astronauts were busy training for it. All astronauts were in training from the time they joined NASA, but for Grissom and Young, Schirra and Stafford, the focus now shifted to a specific mission. Their first assignment was the Gemini mission simulator at the McDonnell plant in St. Louis. This training complex included a flight simulator that matched the inside of a Gemini spacecraft and provided its riders with almost all the sights, noises, and shakings they should meet in a real flight, from prelaunch to postlanding. Because astronauts varied in size* and missions differed in goals and onboard tasks, no two spacecraft were identical, and the mission simulators had to be altered and updated for each flight. But the simulator in St. Louis had not yet been engineered to an exact replica of Spacecraft 3, so the 36 hours that Grissom and Young spent in it over the next two months, as well as the 34 that Schirra and Stafford flew, were devoted mainly to learning general systems and operations.4
 On 10 July 1964, McDonnell workmen began taking the simulator apart to ship it to Houston, there to be set up to match Spacecraft 3. The second Gemini mission simulator was already at the Cape, although not yet updated for Gemini 3. That was supposed to have been done by mid-July, but it was not finished until October. Final checkout took the better part of a month, and the Gemini 3 crews could not begin flying simulations in Florida before 9 November.5
But no such hangup ever left the astronauts with time on their hands. On 10 and 11 May, all four were in St. Louis to review a mockup of the cockpit. In the months that followed, they kept a close eye on their ship, watching as it passed through its series of tests and inspections in the McDonnell plant. They also joined in the testing itself. During the second phase of systems tests in October and November, Grissom and Young spent more than 14 hours in the cockpit, 9 of them while the spacecraft was undergoing altitude chamber tests. Schirra and Stafford were not far behind, with 8 cockpit hours.6
During July and August, the four Gemini 3 pilots (and all their fellows) were in Dallas for a training program on the moving-base abort simulator created by Ling-Temco-Vought, Inc. This device projected the Gemini 3 launch profile in striking detail, complete with such cues as noise, vibration, and a wide range of motions that might be caused by one launch anomaly or another. The trainees also learned how to deal with any number of booster or spacecraft systems malfunctions.7
Throughout their training, the prospective spacemen also kept their more mundane flying skills intact. Each managed to average 25 hours a month in the cockpit of an Air Force jet. They also put in more than 200 hours apiece in innumerable briefings, three of them formal affairs that lasted two days each at Houston, St. Louis, and Cape Kennedy, the others an ongoing series of informal systems familiarizations that were part of each training activity. Periodic reviews of mission plans, physical examinations, fittings for flight suits, sessions on experiments to be carried on the spacecraft and on biomedical aspects of the mission, and any number of other operational matters helped fill the hours to overflowing.8
In October 1964, the Gemini 3 crews tackled still another aspect of training, practice in getting out of their spacecraft after it landed. The three-part program began with a review of egress procedures in the Gemini mockup at the McDonnell plant, then moved to the flotation tank at Ellington Air Force Base, just up the road from the Manned Spacecraft Center. The tank was a king-size swimming pool, where the crews rehearsed (both with and without space suits) climbing in and out of a boilerplate spacecraft that was either floating or submerged.9 Grissom and Young completed the third phase of this training in emergency egress from a floating spacecraft during February 1965.  They rode a boat out into the Gulf of Mexico, where a model spacecraft was dumped into the water. Then, fully suited, they went through the postlanding checklist and practiced getting out of the spacecraft and into their one-man life rafts. The crews also took refresher courses in parachute landing that month.10
During November and December 1964, the four crewmen spent part of their time in Johnsville, Pennsylvania, at the Naval Air Development Center, the site of a man-rated centrifuge run by the Aviation Medical Acceleration Laboratory. The first phase of centrifuge training had taken place in July and August 1963, when Gemini controls and displays had been evaluated and all the astronauts had been spun through acceleration profiles for launch and reentry. For pilots not yet assigned to a mission, the second phase simply provided more of the same. But for the crews of Gemini 3 and Gemini 4,** it was an important part of mission training. They worked in pressure suits, and the others trained in shirtsleeves. Grissom rode the centrifuge for 9½ hours, Young for 11 hours; Schirra and Stafford spent only a little less time in the centrifuge than the prime crew.11
When the mission simulator at Cape Kennedy had been updated to match Spacecraft 3, both crews began working in it off and on for the next four months. During that time, Grissom put in more than 77 hours flying his mission on the ground, rehearsing every phase of his planned flight again and again, not only when everything went right, but also when something went wrong.*** Young put in even more time than Grissom, over 85 hours, in the Cape simulator. Schirra managed to get in 43 hours, Stafford 54.12 In January 1965, Grissom and his fellow crewmen were back in Dallas for more work on the abort simulator, this time focused on how best to deal with each type of booster or spacecraft malfunction. By the time this training was over, Grissom had run through 225 aborts and Young 154; Schirra and Stafford each totaled only slightly less than Young.13
When Spacecraft 3 arrived at complex 19, the crewmen resumed their active role in spacecraft testing. Sandwiching this exercise between trips to Houston for egress and parachute training, Grissom and Young still managed to spend almost 19 hours in the cockpit, beginning with the premate flight test on 14 February and ending with the final  simulated flight on 18 March. Schirra and Stafford got in more than 14 hours of cockpit time. Altogether, the prime crew had logged 33 hours in their spacecraft before the final launch countdown began, and the backup crew had spent 22 hours.14
Nine months of grueling work were ready to pay off. By February 1965, Grissom was sure that "We're ready to go." NASA agreed. Rumors already put Gemini's first manned flight earlier than the officially announced April or May. And NASA Administrator James Webb, speaking at Nebraska Wesleyan University in Lincoln, hinted that the launch might come in late March.15 The men were ready, and the machines very nearly so.