John Houbolt: The Unsung Hero of the Apollo Moon Landings
by William F. Causey
Purdue Univ. Press, 2020
hardcover, 374 pp., illus.
Later this month, NASA is expected to announce awards of contracts for its Human Landing System program to develop a human lunar lander for the Artemis program. Several companies will likely get contracts for initial studies, with NASA later selecting one or two for full-scale development. But, whether they involve lander components being aggregated at the lunar Gateway or a single lander docking directly with an Orion spacecraft, they all share something in common: they will all use a version of lunar orbit rendezvous (LOR) like that pioneered in the Apollo program.
But, 60 years ago, lunar orbit rendezvous was far from the clear choice for landing people on the Moon. As NASA was beginning planning for sending humans to the Moon, the idea of two spacecraft performing a rendezvous in lunar orbit—something yet to have been done in Earth orbit—looked to be too difficult and risky. Yet, thanks in large part to the advocacy of a single NASA engineer, John Houbolt, LOR was the approach NASA adopted, and used successfully.
Houbolt is not quite the “unsung hero” in the subtitle of William Causey’s book about him and his advocacy for LOR: he’s widely acknowledged in the space community today for his efforts, and even at the time of the Apollo 11 landing was invited to the launch and to Mission Control for the landing as a VIP. To the broader public, though, Houbolt is largely unknown, an oversight that Causey seeks to rectify in this book.
Houbolt grew up in the Midwest with an interest in flight and, after graduating with an engineering degree from the University of Illinois in 1942, joined the staff of NACA’s Langley Memorial Aeronautical Laboratory (now NASA’s Langley Research Center) in Virginia. He worked on a variety of aeronautical topics there, like high-speed aircraft. He later earned a doctorate in an unconventional way: with a Rockefeller Public Service Award, he went to the Swiss Polytechnic Institute in Zurich in 1957, skipping the classwork and writing up a dissertation in a matter of months.
While Langley hosted the Space Task Group, NASA’s original human spaceflight effort that resulted in the Mercury program, Houbolt was not part of that group. However, he and others at Langley were intrigued by spaceflight and various issues. Houbolt was particularly interested in the challenge of rendezvous, becoming an expert in the orbital mechanics of spacecraft rendezvous.
By 1960, thoughts turned to the challenge of sending humans to the Moon. The leading idea was “direct landing,” with a rocket launching a spacecraft that directly went to the surface of the Moon and then returned. That, though, made the spacecraft large, which in turn made the rocket that launched it large. A colleague of Houbolt at Langley, Bill Michael, proposed launching the spacecraft to a parking orbit around the Moon and sending a smaller spacecraft to the surface, and asked Houbolt if that made sense.
Houbolt was immediately converted to the idea. “The thought struck my mind, ‘This is fantastic. If there is any idea we have to push, it is this one!’” he later wrote. “I vowed to dedicate myself to the task.” And he did, pushing the idea at every opportunity, including a briefing at NASA Headquarters in December 1960 where Max Faget famously stood up and shouted, “His figures lie!”
Even without Faget’s outburst, LOR was not a major contender at the time. The direct landing approach remained the favorite, along with one that involved two launches, rendezvousing in Earth orbit. Houbolt persisted in his advocacy of LOR, though. He is best known for writing a letter to Robert Seamans, NASA associate administrator, in November 1961 laying out the case for LOR, a missive that, by short-circuiting the agency’s hierarchy, bordered on insubordination. Causey notes in the book that this letter, which started with the line, “Somewhat as a voice in the wilderness,” came six months after an earlier letter he sent to Seamans on the same topic.
Houbolt’s persistence, and the weight of his arguments, gradually won over others at NASA, including vocal critics like Faget. While the direct landing approach had been preferred, it relied on the development of a massive new rocket called Nova, which increasingly looked like it would not be ready in time to meet Kennedy’s goal of a lunar landing by the end of the decade. (As Houbolt wrote in his second letter to Seamans, “Why can’t we think along the lines of deriving a plan to fit a booster, rather than derive a booster to fit a plan?”) Earth orbit rendezvous required two launches of Saturn V boosters in quick succession, something that even Wernher von Braun came to realize would be difficult to pull off.
Most Apollo histories record the date when NASA made the decision to use LOR to be June 1962, when von Braun accepted LOR at the end of a meeting on the topic at the Marshall Space Flight Center. But Causey notes that the White House science advisor Jerome Wiesner remained opposed to that approach even after the decision, calling LOR “the worst mistake in the world” the same day that NASA held a press conference to announce its choice of that approach. That argument continued through memos and White House meetings and even during a visit by Kennedy to Marshall, where von Braun and Wiesner debated it in Kennedy’s presence, just out of earshot of the press pool. By November 1962, though, Wiesner had given up and quietly accepted LOR.
John Houbolt: The Unsung Hero of the Apollo Moon Landings is not a complete biography of Houbolt’s life: it ends once the decision for LOR is secured, with Houbolt leaving NASA shortly thereafter for private industry. It is, though, a detailed examination of the discussions at NASA in its first years about just how it was going to get astronauts to the surface of the Moon and back, and how one man, Houbolt, played a key, if often unheralded, role in that effort.