Beginning in 1946, two XS-1 experimental research aircraft (later redesignated X-1s) conducted pioneering tests at Muroc Army Air Field (now Edwards Air Force Base) in California to obtain flight data on conditions in the transonic speed range. These early tests culminated on October 14, 1947, in the first piloted flight faster than Mach 1.0, the speed of sound.
The XS-1 was the first high-speed aircraft built purely for aviation research purposes. The model was never intended for production. The XS-1 was designed largely in accordance with specifications provided by the National Advisory Committee for Aeronautics (NACA) [now National Aeronautics and Space Administration], paid for by the Army Air Forces, and built by Bell Aircraft Inc. The XS-1 #2 (serial number 46-063) was flight tested by the NACA to provide design data for later production high-performance aircraft.
The research techniques used in the X-1 program became the pattern for all subsequent X-craft projects. The NACA X-1 procedures and personnel also helped lay the foundation of America's space program in the 1960s. The X-1 project defined and solidified the post-war cooperative union between U.S. military needs, industrial capabilities, and research facilities. The flight data collected by the NACA in the X-1 tests then provided a basis for American aviation supremacy in the latter half of the 20th century.
As a result of the X-1's initial supersonic flight, the National Aviation Association voted its 1948 Collier Trophy to be shared by the three main participants in the program. Honored at the White House by President Truman were Lawrence "Larry" Bell for Bell Aircraft, Captain Charles E. "Chuck" Yeager for piloting the flights, and John Stack of NACA for the NACA contributions.
The sharing of this award exemplified the partnership among the three participants that had led to this significant aviation milestone. Further testifying to the partnership between the NACA and the Air Force (as the Army Air Forces [AAF] became in September 1947) in the latter part of the program was a statement by Major General Albert Boyd, who had headed Wright Field's Flight Test Division and then the Air Force's flight test unit at Edwards:
The combination of talents served two purposes. First, the accelerated USAF program permitted a rapid exploration of the capabilities of the X-1 to the highest speed attained; and, secondly, the detailed NACA program provided the comprehensive data needed to develop complete envelopes of aircraft performance which might reveal unsatisfactory flight characteristics at some intermediate point. When considered separately, each program was a notable contribution to flight research, however, when combined, the results stand as a monumental tribute to both the USAF and the NACA since the sonic barrier monster was not only completely licked, but a blow-by-blow account of its defeat was recorded for future use.