Chapter 3

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 “appendix-roved” 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.