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Brown's Lunar Exploration Working Group Michael's Paper on a "Parking Orbit" The Feelings Against Lunar-Orbit Rendezvous The Space Task Group's Early Skepticism President Kennedy's Commitment |
The LOR Decision In the months following Houbolt's second letter to Seamans, NASA gave LOR the serious consideration for which Houbolt had been crusading. To the surprise of many inside and outside the agency, the darkhorse candidate became the front-runner. Several factors worked in its favor. First, there was growing disenchantment with the idea of direct ascent because of the time and money necessary to develop the huge Nova rocket. Second, there was increasing technical apprehension over how the relatively large spacecraft demanded by Earth-orbit rendezvous would be able to maneuver to a soft and pinpoint landing on the Moon. As Langley's expert on the dynamics of rendezvous, Art Vogeley, explained, "The business of eyeballing that thing 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."110 The first major group to favor LOR was Bob Gilruth's STG. During the critical months of the Apollo mission mode debate, this group was harried not only with planning for the first Mercury orbital flight but also with packing and leaving for its new home in Houston. Once the STG's engineers started closely examining the problems of landing a spacecraft on the Moon and had the analysis confirmed by industry, they, too, saw the wisdom of the staged approach built into LOR. It possessed a certain elegance of economy that was absent in the other schemes. During an interview in the late 1980s, Houston's Max Faget recalled the details of how the Manned Spacecraft Center finally became convinced that LOR was the right choice. By early 1962, "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," as well as between Houston and the Lewis Research Center. "Accordingly, we invented a new proposal for our own and von Braun's approach. It involved a simpler descent engine, called the lunar crasher, which Lewis would do. 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." But at that point, Faget and his colleagues in Texas "ran into a real wall." Initially, their thinking had been that the landing would be done automatically with radar and instrument control. But the astronauts, along with a growing number of NASA engineers (primarily at Langley), began to argue that the astronaut-pilots were going to need complete control during the last phases of landing and therefore required a wide range of visibility out of the descending spacecraft. How to provide that visibility "with a landing rocket big enough to get the command-and-service module down to the lunar surface and wide enough to keep it upright" was the problem that Houston began tackling in early 1962, and they found out quickly that they could not solve it. "We toyed with various concepts," Faget remembers, such as putting a front viewing-porch on the outside or a glass bubble on top of the command module similar to the cockpit of a helicopter. But all of the redesigns had serious flaws. For example, "the porch would have to be jettisoned before lift-off from the moon, because it would unbalance the spacecraft." "It was a mess," Faget admitted. "No one had a winning idea. Lunar-orbit rendezvous was the only sensible alternative."111 Houbolt's role in the STG's eventual "conversion" to LOR cannot be described without upsetting someone—or at least questioning the correctness of some key player's memory. Faget, Gilruth, and others associated with the Manned Spacecraft Center believe that Houbolt's activities were "useful," but hardly as vital as many others, notably Houbolt himself, believe. "John Houbolt just assumed that he had to go to the very top," Gilruth has explained, but "he never talked to me." It is Gilruth's belief that LOR "would have been chosen without Houbolt's somewhat frantic efforts." The "real work of convincing the officials in Washington and Huntsville," he says, was done "by the spacecraft group in Houston during the six or eight months following President Kennedy's decision to fly to the moon." In other words, they were the ones who sold it, first to Huntsville and then, together with von Braun, to NASA headquarters. Houbolt's out-of-channels letter to Seamans was thus irrelevant.112 Houbolt believes that the STG's version is self-serving "baloney." He talked to Gilruth or his people many times; they never told him that they were on his side. If Gilruth or some other influential officer in the leadership of the space program had just once said to him, "You can stop fighting. We are now on your side; and we'll take it from here," then, Houbolt says, he would have been satisfied. But they never said anything like that, and they certainly did not "during the six or eight months" after Kennedy's speech. In fact, their words always suggested the opposite. It was not until early 1962, as seen in the prodding from Joseph Shea, that the STG gave any indication that it, too, was interested in LOR.113 Significantly, the outsiders or third parties to the question of Houbolt's role in ultimately influencing the STG's position tend to side with Houbolt. Bob Seamans remembers nothing about the STG showing anything but disdain for LOR during 1961.114 Nor does George Low. To the best of his recollection, "it was Houbolt's letter to Seamans that brought the Lunar Orbit Rendezvous Mode back into the picture." It was only after the letter that a group within the STG, under Owen Maynard, began to study LOR. According to Low, "the decision was finally made" about the lunar-landing mission mode "based on Houbolt's input" and on the results of the systems engineering studies carried out at the behest of Shea's Office of Manned Space Flight Systems, "Without a doubt," in Low's view, the letter Houbolt sent to Seamans in November 1961 and the discussions at headquarters that it provoked "were the start of bringing LOR into Apollo."115
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