Bob Gilruth: Architect of Mercury, Gemini, and Apollo

During the 50th anniversary of the Moon landing, the astronauts and mission controllers will certainly be celebrated, but the key NASA managers who created and led the early U.S. human space program may not be. I recently highlighted the career of one of them, Abe Silverstein, and in this essay I feature Robert R. “Bob” Gilruth (1913-2000), who, more than anyone else, created the Mercury, Gemini, and Apollo programs and the Houston center that managed them. 

Gilruth, a shy and sometimes taciturn aeronautical engineer from Minnesota, was thrilled to join the Langley Laboratory in Hampton, Virginia, in early 1937. It was the primary and original research center of the National Advisory Council for Aeronautics (NACA), the predecessor of NASA. There he quickly became an expert in flight test instrumentation, putting rigor into investigations of the handling characteristics of new airplanes. During World War II, he moved into research on the cutting edge of the new aeronautics: transonic and supersonic flow. After the war, he created and led the Pilotless Aircraft Research Division, which launched rockets from Wallops Island on the Eastern Shore of Virginia—a NASA launch facility to this day—to test the aerodynamics of high-speed aircraft and missiles. 

Not long after the Space Race broke out in fall 1957, he was called to Washington, along with several other up-and-coming NACA leaders like Silverstein, to examine how to transform the agency into the National Aeronautics and Space Administration. As his Langley group was already studying what it would take to put a human in orbit, Gilruth was appointed to head the Space Task Group (STG). He began with only 45 people and the daunting challenge of Project Mercury, which aimed to put an American in space before the Soviets. Under Gilruth’s superb leadership, STG expanded massively, chose the first seven astronauts in 1959, and began flying “boilerplate” test capsules that same year. It moved on to launching chimpanzees and humans on suborbital trips into space by 1961. But once again, America was bested by the Soviet Union, which sent Yuri Gagarin on one orbit around the Earth on April 12, 1961. On May 5 of that year, Alan Shepard became the first American in space when a Redstone rocket launched his MercuryFreedom 7 spacecraft over 100  miles high and 300 miles downrange from the launch site at Cape Canaveral, Florida. 

Gagarin’s flight provoked the new President, John F. Kennedy, to ask Vice President Lyndon Johnson to find a space program that could potentially beat the Soviets. Bob Gilruth was naturally one of those who were consulted by Johnson and NASA Administrator James Webb about what to do. On May 25, Kennedy proposed to Congress that the United States accept the challenge of “landing a man on the Moon and returning him safely to the Earth” by the end of the decade. Even though Gilruth had been part of the consultations, he was “aghast” when he heard the speech, as he contemplated such an ambitious schedule – NASA was still months away from even orbiting an astronaut. 

The relentless, exhausting pace of the space program got even more intense in winter 1961/62, as STG struggled to pull off that feat while simultaneously building up Project Apollo and moving to Houston, Texas. Kennedy’s Apollo decision led to a quintupling of the agency’s budget in four years, and necessitated many new NASA facilities, of which Houston’s Manned Spacecraft Center (MSC) was the most prominent. Gilruth was naturally its founding director. After multiple delays, on February 20, 1962, MSC finally sent John Glenn on three orbits around the Earth. When the President decorated Gilruth at the White House, along with Glenn and others, the MSC Director was overcome with emotion, but was characteristically unable to say much or take any credit. 

In the midst of all this, Bob Gilruth was also farsightedly pushing for a program to bridge the gap in capability between the Mercury and Apollo vehicles. Another spacecraft was needed for Earth-orbit experience in rendezvous and docking, spacewalking, and long-duration spaceflight. In December 1961, NASA approved Project Gemini, which carried out ten crucial and successful missions in 1965 and 1966. Gilruth was also a key supporter of the mission control concept of Christopher Kraft, who eventually succeeded him as the director of MSC (which, after 1973, became known as Johnson Space Center.

Kraft was featured on the cover of TIME magazine in 1965, as was the most famous NASA manager, Wernher von Braun, years earlier. Gilruth, the maestro of Houston, remained almost unknown to the American public. 

When a launch pad fire killed the first Apollo crew, including Mercury veteran Gus Grissom, on January 27, 1967, it hit Gilruth very hard. He was a father figure to many of the astronauts and was especially close to the first groups. Like many other key NASA leaders, he also felt personally responsible for the Apollo spacecraft’s many flaws, and thus for the three astronauts’ deaths. Although he was as thrilled as everyone else on the team by the outstanding successes of 1968 and1969, most notably the lunar firsts of Apollo 8 and 11, as flights went on, he began to feel that the agency was gambling with the lives of the astronauts. That feeling was crystallized by the near-disaster of Apollo 13 in April 1970. Gilruth was not sorry when the agency cancelled the last two landings, 18 and 19, mostly to save the money as public support for the space program fell. He left MSC in late 1972, shortly before the last mission, Apollo 17, and retired in early 1973. 

Bob Gilruth was one of a half dozen NASA leaders most critical to landing humans on the Moon only eight years and two months after President Kennedy proposed it. He thus richly deserves to be remembered as we celebrate Apollo 11 today.  

Michael J. Neufeld is a senior curator in the Museum’s Space History Department and lead curator for Destination Moon, a new exhibition that opens in the National Mall Building in 2022, and for Destination Moon: The Apollo 11 Mission, a travelling exhibit featuring the command module Columbia.