John Yardley, who died on June 26th aged 76, was one of that remarkable band of engineers who made it possible, through the mobilisation of American industry, to create a space programme capable of landing men on the moon.
It was an achievement that meant welding together a vast range of disparate commercial, and usually competing, organisations that ordinarily might be expected to collaborate only under the exigencies of war.
John Yardley's career was a brilliant illustration of how this was achieved: he directed the teams that built the capsules for the initial Mercury and Gemini missions, was involved in all NASA's manned space flights for almost two decades, and was management supremo for the development of the US re-usable space shuttle.
He belonged to a generation of highly-motivated managing engineers who moved between industry and government jobs. This mobility provided a transfer of knowledge and expertise in high technology that would normally have been discouraged in the competitive world of industry; the result was the phenomenal growth of the US space industry.
He was born in St Louis, Missouri. His father was a baseball player, but John Yardley was more attracted to building model airplanes than to sport. A US navy ensign from 1943-46, he graduated in aeronautical engineering from Iowa State College with the wartime class of 1944, and took a master's degree in applied engineering from Washington University, St Louis, in 1950.
He began his career as a structural and aeronautical engineer at the McDonnell Aircraft Corporation in St Louis, in 1946, becoming chief strength engineer 10 years later.
After the Soviet Union launched the first artificial satellite, Sputnik, in 1957, aeronautical engineers were galvanised into designing spacecraft instead of aeroplanes. Even so, the US aerospace industry was still a fledgling when, in May 1961, President Kennedy set the goal of landing an American on the moon by the end of the decade.
John Yardley's career in the space programme began in 1958 as project engineer for the design of the one-man Mercury capsule, which carried Alan Shepard into sub-orbital flight in 1961, making him the first American in space. Fourteen years later, John Yardley could still recall: "I never felt such a thrill in my life as that flight of Shepard's."
In the early 1960s, he was transferred to Cape Canaveral, Florida, to manage launching operations for the Mercury and Gemini spacecraft, and, in 1964, took over as technical director for the two-seater Gemini flights, which gave American astronauts more time in orbit in preparation for the moon assault by the Apollo mission. As NASA's associate administrator for manned space flight from 1974-81, he carried responsibility for development of the space shuttle, earning a formidable reputation as a trouble-shooter.
He was also known for Yardley's law, "Pretty is what works." It was his response to a visitor who described the Mercury space capsule as looking like a wastepaper basket; the reply now belongs to the legion of wisdoms that originated in the American space industry and have passed into the vocabulary of technology folklore.
After the Apollo moon landings, he took charge of the McDonnell Douglas work on the Skylab space station that was launched in May 1973. In a working life of 10 months, it demonstrated that crews could survive in space much longer than previously thought possible, and restore damaged and faulty equipment. It effectively marked the end of the first chapter of US manned spaceflight.
John Yardley then became president and general manager of McDonnell Douglas's space-shuttle contract, but the seat was scarcely warm before he was offered the greater challenge of overall responsibility for the space shuttle at NASA. He was charged with getting the shuttle project, which was running behind schedule, on track for its first launching in 1981.The space shuttle, Columbia, duly made its maiden flight that April.
Speaking about his anxieties before the event, John Yardley said: "The things that you have to be careful about are the unknowns, things that have never happened before. A new engineering gremlin could crawl out of the woodwork, one nobody could have predicted."
Shortly after the shuttle's inaugural success in 1981, John Yardley returned to McDonnell Douglas. He retired as senior vice-president in 1989, and is survived by his wife of 55 years, Phyllis, four daughters and a son.
John Finley Yardley: born 1925; died, June 2001