The SR-71 Blackbird
The joint NASA-Air Force YF-12 research program lasted 10 years (1969-1979) and produced a wealth of data on materials, structures, loads, heating, aerodynamics, and performance for high-speed aircraft.
Two YF-12s were flown in a joint Air Force-NASA research program at the NASA Flight Research Center (after 1976, the NASA Dryden Flight Research Center) between 1969 and 1979. A third shared plane, piloted primarily by the Air Force, was lost to an in-flight fire in 1971.