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John C. Houbolt was for a long time a lonely advocate for lunar orbit rendezvous. (credit: NASA)

“Do we want to get to the Moon or not?” (part 2)

Dr. John C. Houbolt and the decision for lunar orbit rendezvous

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Colonel Donald H. Heaton was about to get more than he perhaps expected. And he would not be alone.

Houbolt sat down at his typewriter and began to compose what is arguably one of the most significant and professionally risky documents in the history of NASA.

On October 31, Houbolt’s committee issued their version of the “minority report”: Manned Lunar-Landing through Use of Lunar-Orbit Rendezvous.1 Houbolt was the primary author of this book-length, two-volume monograph. The forward contains Houbolt’s initials, along with the following paragraph: “The significant advantage brought out by this procedure is the marked reduction in escape weight required; the reduction is, of course, a direct reflection of the reduced energy requirements brought about by leaving a sizable mass in lunar orbit, in this case, the return capsule and return propulsion system.”

Critical time was evaporating for settling the mode argument. Although John Houbolt knew the problems with Direct Ascent, his view regarding Earth Orbit Rendezvous was more nuanced: he was not averse to the idea of launching multiple rockets to assemble a vehicle in space. It was that landing and launching a large, heat-shielded ship to and from the Moon’s surface would require even more launches than Lunar Orbit Rendezvous would ever require. More launches would be like a chain with more links—if any link ruptured, the whole chain would split apart. Likewise, a lunar landing mission that would depend upon two or three launches would collapse if any single launch failed. Three launches tripled your odds of failure.

Houbolt sat down at his typewriter and began to compose what is arguably one of the most significant and professionally risky documents in the history of NASA. He decided to advance his arguments in writing under his own letterhead. And not to his boss, Robert Gilruth, who was not sympathetic to rendezvous. Instead, he directed the letter to the man whom he had spoken to personally about LOR, and who had the power to do something about it. He wrote his letter to the Associate Administrator of NASA, Robert Seamans.

November 15, 1961

Dear Dr. Seamans:

Somewhat as a voice in the wilderness, I would like to pass on a few thoughts on matters that have been of deep concern to me over recent months…I fully realize that contacting you in this manner is somewhat unorthodox; but the issues at stake are crucial enough to us all that an unusual course is warranted…2

Houbolt’s tone was cautious at first. It did not remain that way for long.

…it is conceivable that after reading this you may feel that you are dealing with a crank. Do not be afraid of this.

After telling Seamans what he should not be afraid concerning cranks, Houbolt continued:

The thoughts expressed here may not be stated in as diplomatic a fashion as they might be, or as I would normally try to do, but this is by choice and at the moment is not important. The important point is that you hear the ideas directly, not after they have filtered through a score or more of other people, with the attendant risk that they may not even reach you.

At this point, Houbolt went through a recounting of how NASA had arrived at its present mode stalemate, with a recounting of how Lunar Orbit Rendezvous had been submitted to committee after committee, then summarily discounted. He recited the foundations of this indecision as a partial byproduct of the agency’s present booster dilemma—here Houbolt’s stated an optimistic (and unrealistic) estimate that LOR could be accomplished “by means of a single (Saturn) C-3, its equivalent, or even something less.” (The Saturn C-3 that von Braun’s team had on the drawing boards, with its two first stage F-1 engines, would have been drastically underpowered for such a job.)

The greatest objection that has been raised about our lunar rendezvous plan is that it does not conform to the “ground rules”. This to me is nonsense; the important question is; Do we want to get to the moon or not?, and, if so, why do we have to restrict our thinking along a certain narrow channel. I feel very fortunate that I do not have to confine my thinking to arbitrarily set up ground rules which only serve to constrain and preclude possible equally good or perhaps better approaches.

Houbolt continued with a dismantling of some of those ground rules, one of them being the requirement for the Apollo Command/Service Module with its three-man crew execute the lunar landing: “If two men can do the job, and if the use of only two men allows the job to be done, then why not do it this way?” He laid out arguments for a lightweight lunar lander by way of analogy: “Figuratively, why not go buy a Chevrolet instead of a Cadillac? Surely a Chevrolet gets one from one place to another just as well as a Cadillac, and in many respects with marked advantages.”

He released months of frustration in portions of the letter:

I have been appalled at the thinking of individuals and committees on these matters. For example, comments of the following type have been made: “Houbolt has a scheme that has a 50 percent chance of getting a man to the moon, and a 1 percent chance of getting him back.” This comment was made by a Headquarters individual at high level who never really has taken the time to hear about the scheme, never has had the scheme explained to him fully, or possible (sic) even correctly, and yet he feels free to pass judgment on the work. I am bothered by stupidity of this type being displayed by individuals who are in a position to make decisions which affect not only the NASA, but the fate of the nation as well.

After covering topics that ranged from “PERT chart folly” to the impracticality of a Direct Ascent to the moon by way of Nova, Houbolt devoted space to dismissing problems that could arise over a shortage of money. He did so by explaining what NASA Administrator Webb’s job was.

If this is the situation, then the answer is simply that’s why we have Webb and his staff. That is why he was chosen to head the organization, this is one of his major functions to ask the question, do we want to do a job or not?

Houbolt concluded by lauding Lunar Orbit Rendezvous and its champions at the Langley Field Center that had stood with him through months of opposition.

Give us the go-ahead, and a C-3, and we will put men on the moon in very short order - and we don’t need any Houston empire to do it.

In closing, Dr. Seamans, let me say that should you desire to discuss the points covered in this letter in more detail, I would welcome the opportunity to come up to Headquarters to discuss them with you.

Respectfully yours,
John C. Houbolt

Nine pages, single-spaced, with attachments. Houbolt mailed the letter and waited.

Yes, he admitted to Holmes, Houbolt probably should have followed proper channels in arguing for his ideas. But those ideas appeared robust and well-reasoned.

In all, he waited just over two weeks. The reply from Seamans was four paragraphs. Within a single page, Seamans thanked Houbolt for his letter. He assured him that his findings “deserve serious consideration” and that he appreciated “the vigorous pursuit of your ideas.” His confidence, however, rested in the belief that “we are approaching the question of Manned Lunar Landing fairly and frankly and that all views are being carefully weighed in our continuing studies.” He concluded by promising to forward the material to Brainerd Holmes “for his evaluation and recommendations.”

If Seaman’s letter landed with a dull bureaucratic thud, it was drowned out by what happened when Houbolt’s letter hit Holmes’ desk. D. Brainerd Holmes had just been hired by NASA as the Director of the Office of Manned Space Flight.3 While he was sympathetic to the idea of rendezvous, he was decidedly not happy with the approach Houbolt had taken by executing an end-run around proper channels. Holmes responded by continuing to roll the information downhill: he forwarded the letter he received from his boss (Seamans) to the next person down the chain, George Low, NASA’s Chief of Manned Space Flight.

Low read Houbolt’s letter carefully. Yes, he admitted to Holmes, Houbolt probably should have followed proper channels in arguing for his ideas. But those ideas appeared robust and well-reasoned. Not only should they be seriously considered, Low went so far as to recommend that Houbolt be added to Holmes’ staff in Washington.4

Joe Shea

In fact, a change to Holmes’ staff in 1962 finally tipped the scales irrevocably toward Lunar Orbit Rendezvous. But that change had nothing directly to do with Houbolt, who remained at his position at Langley. Instead it centered on a man hired in January as NASA’s new Deputy Director For Systems Engineering, Joe Shea.5

Although the 35-year-old Shea already had a lengthy history in aerospace (he had done wonders in rescuing the inertial guidance systems on the Titan II ICBM project), he came to his brand-new position in NASA knowing almost nothing about the great mode debate. Regardless, Holmes hired him to bring a fresh set of eyes to the problem, and wrest a solution from it once and for all. Shea’s background as a man who could wrap his mind around both engineering and managerial issues made him a promising candidate to not only clarify the mode problem, but to also bring harmony between the field centers (whose members often hated each other) under the authority of NASA Headquarters in Washington (whom the centers often hated even more).6

After Shea took the job, Holmes decided to begin his education by promptly routing the Houbolt letter to his new deputy for an evaluation of its validity and usefulness.

Unlike so many who had come before him who remained mired in the gauntlet of turf warfare, Shea realized that, when it came to the utility of LOR, he didn’t know what he didn’t know… yet. He made up his mind to learn, and that meant learning whatever he could about all three modes. With the same talent that Shea had exhibited in linking his management and engineering skills, he also intuitively grasped the intrinsic linkage between booster development and mode selection and that both matters had to be decided upon together. Soon.

During initial briefings from Holmes and Robert Seamans, Joe Shea learned in his new job that NASA did not know how it was going to reach the Moon. However, the briefings did reaffirm how the agency could reach it, and that the mode for reaching it would likely involve rendezvous (indeed, NASA made a key decision for rendezvous on January 9 by committing to the development of the “Saturn C-5”, which would permit a rendezvous mode but precluded the development of a Nova booster for Direct Ascent.)7 Moreover, Shea clearly gathered from Seamans that Lunar Orbit Rendezvous—based largely on the letter from Houbolt—deserved a renewed consideration, despite its perceived unknowns.

Shea left those meetings with a few basic inclinations. For one, he was leery of Direct Ascent and the illogic of going down the engineering path to the immense Nova booster. On the other hand, Earth Orbit Rendezvous seemed to make a good deal of engineering sense. And Lunar Orbit Rendezvous? He thought Seamans was right: the data they had made it attractive. In fact, Shea wondered why so many within NASA had harbored so much animosity towards it.

“Look, what’s going on here? Why haven’t you been thinking about this thing longer? Looks pretty good to me.”

Shea decided to find out from the source. In January, he made arrangements to visit the Langley Center to privately discuss LOR with John Houbolt. Additionally, he decided to gauge the institutional reaction to Houbolt’s ideas by arranging for him to present a briefing to himself and several senior representatives of the former Space Task Group—reformed in November 1961 into a new field center known as the Manned Spacecraft Center to be based in Houston—including Houbolt’s previous nemesis, Max Faget.

Houbolt took his place at the head of the conference room and launched into his explanation of, and advocacy for, Lunar Orbit Rendezvous. After the conclusion, Shea turned to the assembled audience of NASA managers. “Look, what’s going on here? Why haven’t you been thinking about this thing longer? Looks pretty good to me.”8

The room stirred.

LOR, it became clear, seemed like a good idea to them too.

Perhaps it was Shea’s directness in simply asking the question, but it was also likely the addition of time and thoughtfulness amongst the room’s listeners that drew them to surprise Shea with their answers. And in truth, some of those people within the old Space Task Group had felt sympathy for rendezvous all along—they just weren’t ready to hang the entire lunar program, and the astronauts’ very lives on a rendezvous that would take place around the Moon instead of the Earth. And Max Faget still harbored doubts around Houbolt’s weight-savings numbers as unrealistically optimistic (a concern that he was later proved right about, as evidenced by Houbolt’s letter to Seamans where he insisted that the entire combined spacecraft could probably be boosted on a three million pound thrust Saturn C-3).9 But time had played its part: the Langley engineers had attended Houbolt’s briefings, and they had their private, informal chats with him in hallways and lunchrooms. And eventually, over time, the logic behind the use of a specialized lander to reach the Moon had pushed their minds from closed to open.

Joe Shea was quickly acquiring enough knowledge to pass from troubled ignorance to informed uncertainty. He wasn’t sure which mode was the correct one, but he had learned that Lunar Orbit Rendezvous deserved the same attention given to Earth Orbit Rendezvous and its huge, all-in-one Apollo spacecraft. Upon his return to Washington, he conferred with Holmes about the next, critical step in finally determining NASA’s lunar mode: the commissioning of an independent (and hopefully unbiased) study, one that could be evaluated by Headquarters and not on the turf of any particular field center (the Manned Spacecraft Center was getting ready to commission their own study, and Shea was determined to control the process and move first.) The study, at length and in detail, would be used to evaluate the many open questions pertaining to the two front-running rendezvous modes and how they would affect both Apollo spacecraft and Saturn booster development.

In March, one more stroke of irony played out in the form of an old player in the mode drama. On the first of that month, Headquarters granted a contract to Vought to weigh the benefits of Earth vs. lunar rendezvous in a lunar landing mission. Having gone nowhere with their original MALLAR studies the year before, they would now be called upon to help NASA make up its collective mind regarding the best use of rendezvous to reach the Moon.10

Shea would not make it an easy task for them. After a month of work, critical questions arose pertaining to the old problems of weight, specifically whether a single Saturn C-5 with its five F-1 engines would have the capacity to lift the Apollo Command/Service Module and a lunar lander. A single launch vehicle would be a major asset that Lunar Orbit Rendezvous alone could leverage, but the work done by Vought Astronautics continued to point out that Houbolt’s weight estimates regarding the lander were far too optimistic. Were they off by a margin sufficient to rule out using the Saturn C-5?

Joe Shea told them to go back to the drawing board to update the numbers. Politically, he and Holmes felt that whichever rendezvous mode was selected, agreement and commitment had to be reached between Headquarters and the two critical field centers involved in the Apollo program: Houston’s Manned Spacecraft Center and Wernher von Braun’s Marshall Space Flight Center. To get their buy-in, Shea asked for their updated research studies, and for those studies to be presented in a round of meetings to summarize the debate. He then placed a milestone on the flow chart for Holmes—he promised that a preliminary recommendation for a mode would be reached in the middle of June.11

The decision

In the end, there were many factors in the mix: weight, the launch vehicle (or vehicles), and money. But in the final analysis, it was the use of a small, purpose-built lunar landing module that made Lunar Orbit Rendezvous the mode NASA chose for executing a landing on the moon by the end of the decade.

At the press conference, Brainerd Holmes spoke of the continuing need for research into all three modes because “all are feasible.” In reality, there was no going back.

An upwelling of considered engineering opinions started to flow in the same direction, pushing the collective arguments away from the illogic of any mode that did not include the use of a dedicated landing vehicle. Arthur Vogeley, who was a key member of the Space Task Group and was intimately involved in the mode debates, recalled the final tipping point for LOR very clearly: “The business of eyeballing that thing (an Apollo Command/Service Module with its landing stage) down to the Moon really didn’t have a satisfactory answer. The best thing about LOR was that it allowed us to build a separate vehicle for landing.”12

In the 1980’s, Max Faget—one of John Houbolt’s original antagonists—expressed himself on the matter:

“…we found ourselves settling into a program that was not easy to run, because so many different groups were involved. In particular, we were concerned about the big landing rocket, because landing on the Moon would, of course, be the most delicate part of the mission. The landing rocket’s engine, which would be controlled by the astronauts, would have to be throttleable, so that the command-and-service module could hover, and move this way and that, to find a proper place to touch down. That meant a really intimate interface, requiring numerous connections, between the two elements… Accordingly, we invented a new proposal for our own and von Braun’s approach. It involved a simpler descent engine, called the lunar crasher… It wouldn’t be throttleable, so the interface would be simpler, and it would take the astronauts down to a thousand feet above the lunar surface. There it would be jettisoned, and it would crash onto the moon. Then there would be a smaller, throttleable landing stage for the last thousand feet, which we would do, so that we would be in charge of both sides of that particular interface.”13

He reminisced about how he and others agonized over how to get an Apollo Command/Service Module onto the lunar surface in one piece by augmenting couches and windows that faced straight up with a custom, down-facing “porch”: “the porch would have to be jettisoned before liftoff from the moon, because it would unbalance the spacecraft. It was a mess… No one had a winning idea. Lunar-orbit rendezvous was the only sensible alternative.”14

Many years have passed since 1961, and the men of the Space Task Group had differing and often conflicting memories of who supported LOR at that time and who did not (Houbolt later commented that the notion that he had widespread support within the STG in 1961 was “baloney.”) But clearly there was a gathering conviction in 1962 within its successor organization, the Manned Spacecraft Center, that LOR was the way to put a man on the Moon and return him safely to Earth. The problem now was convincing Wernher von Braun and his people at Huntsville, and the men at NASA Headquarters in Washington, to go along with it too.

Throughout early 1962, von Braun’s group was still holding out for EOR, including its prodigious number of Saturn launches and the hope of supporting a space station in earth orbit. But on June 7, 1962, the director himself turned the tables on his own center. In a briefing for Joe Shea at Marshall, von Braun gracefully conceded the following:

“We at the Marshall Space Flight Center readily admit that when first exposed to the proposal of the Lunar Orbit Rendezvous Mode we were a bit skeptical—particularly of the aspect of having the astronauts execute a complicated rendezvous maneuver at a distance of 240,000 miles from the earth where any rescue possibility appeared remote. In the meantime, however, we have spent a great deal of time and effort studying the four modes [Earth-orbit rendezvous, LOR, and two Direct Ascent modes, one involving the Nova and the other a Saturn C-5], and we have come to the conclusion that this particular disadvantage is far outweighed by [its] advantages....”

“We understand that the Manned Spacecraft Center was also quite skeptical at first when John Houbolt advanced the proposal of the Lunar Orbit Rendezvous Mode, and that it took them quite a while to substantiate the feasibility of the method and finally endorse it.”

“Against this background it can, therefore, be concluded that the issue of ‘invented here’ versus ‘not invented here’ does not apply to either the Manned Spacecraft Center or the Marshall Space Flight Center; that both Centers have actually embraced a scheme suggested by a third source.... I consider it fortunate indeed for the Manned Lunar Landing Program that both Centers, after much soul searching, have come to identical conclusions.”15

The formal announcement from von Braun came as a surprise, particularly to many of those at Marshall who were still proponents of EOR. After June 7 they were not disposed to differ from their director. Marshall was now on record: Lunar Orbit Rendezvous was the preferred mode for reaching the Moon. And it was accompanied by von Braun’s invocation of the imperative of time, and that a decision must be made by July 1. That put the ball squarely in NASA Headquarters’ corner for a final decision in three weeks.

By this time, the committee within NASA Headquarters that was responsible for a formal recommendation on the preferred mode for Apollo was known as the Manned Space Flight Management Council. Having been persuaded by personal briefings from John Houbolt and from the findings coming out of Marshall, on June 22 the Council made a formal recommendation in favor of LOR.

“Congratulations, John. They’ve adopted your scheme. I can safely say I’m shaking hands with the man who single-handedly saved the government $20 billion.”

NASA Administrator James Webb had been in favor of Direct Ascent for quite some time. By July, both the ticking clock and the weight of engineering opinion had shifted the center of gravity for the mode preference irrevocably toward LOR. On July 11 Webb, Robert Seamans, Brainerd Holmes, and Joe Shea sat before the press at NASA Headquarters in Washington. The formal announcement was made: while NASA would continue studies related to Earth Orbit Rendezvous and Direct Ascent with NOVA, NASA would “base the next phase of its planning, research and development, procurement and space flight program on the use of the advanced Saturn (C-5 configuration) to accomplish the initial manned lunar landing and recovery, using the lunar orbit rendezvous procedure as the prime mission mode.”16

press conference
The NASA press conference where it was announced that Apollo would go to the Moon by way of Lunar Orbit Rendezvous. (From left to right) James Webb, Robert Seamans, Brainerd Holmes and Joseph Shea. (credit: NASA)

At the press conference, Brainerd Holmes spoke of the continuing need for research into all three modes because “all are feasible.”17 In reality, there was no going back. NASA was committed: the Apollo program, along with the harnessed power of America’s economic and engineering talent, would risk the entire endeavor of a manned landing on the Moon before 1970 on the strategy of Lunar Orbit Rendezvous. In retrospect, few would argue that the decision was the wrong one. And even with the mode decision having been reached in July of 1962, meeting the landing goal by 1970, to quote Wellington after Waterloo, “was a near run thing.” The advantage that Holmes and others foresaw of only having to manage one “additional development”—a lunar landing module—precipitated so many difficulties that the Lunar Module did not make its piloted debut, after months of delay, until March 1969. But EOR and Direct Ascent, with their new technologies of tanker stages and/or in-orbit refueling techniques and/or NOVA launches would have worsened that situation by many factors. Holmes, Shea, and even von Braun knew it. In the end, the findings went into their conclusions, not the other way round.

On the day of NASA’s July press conference, a man by the name of Ed Garrick found himself in Paris gazing at a newspaper. Within was an article about NASA and their announcement, which Garrick read with some interest. Lunar Orbit Rendezvous: Garrick knew the term. He’d heard it many times, he knew of the frustrations surrounding it, especially those frustrations and risks suffered by those pushing it. Garrick had leant an ear many times over the previous months as his very bright and rather hard-headed employee, John C. Houbolt, risked his career by briefing, arguing and persisting. Without Houbolt, Garrick thought, NASA would have figured things out eventually. After a few years or so.

Garrick picked up the paper. He took it with him as he went to meet Houbolt before he undertook a series of briefings for a NATO committee on a subject that was his specialty: aerodynamic turbulence. Garrick greeted him. He shook his hand, and showed him the newspaper.

“Congratulations, John. They’ve adopted your scheme. I can safely say I’m shaking hands with the man who single-handedly saved the government $20 billion.”18


  1. John C. Houbolt, et al, Manned Lunar-Landing through Use of Lunar-Orbit Rendezvous, National Aeronautics and Space Administration, Langley Research Center
  2. John C. Houbolt, Letter to Seamans
  3. AmericaSpace, “NASA 'Space Planner' Brainerd Holmes Dies,” January 14, 2013. 14.
  4. Hansen, Enchanted Rendezvous, page 35
  5. NASA Johnson Space Center Oral History Project. “Biographical Data Sheet: Joseph Francis Shea.”
  6. Charles Murray and Catherine Bly Cox, Apollo: The Race To The Moon. p 134-135
  7. NASA. The Apollo Spacecraft - A Chronology. Part 3B.
  8. Apollo: The Race To The Moon p 134-135
  9. Ibid., page 128
  10. Brooks and Grimwood, Chariots for Apollo, Chapter 3, page 78
  11. Ibid.
  12. Arthur W. Vogeley interview, Hampton, VA ,July 17, 1989
  13. Hansen, Enchanted Rendezvous, page 37
  14. Henry S. Cooper, “We Don’t Have To Prove Ourselves,” The New Yorker, September 2, 1991
  15. Hansen, Enchanted Rendezvous, page 39-40, “Concluding Remarks by Dr. Wernher von Braun about Mode Selection for the Lunar Landing Program Given to Dr. Joseph F. Shea, Deputy Director (Systems) Office of Manned Space Flight,” 7 June 1962
  16. LOR press conference information
  17. Ibid.
  18. Hansen, Enchanted Rendezvous, page 40