EDWARDS AIR FORCE BASE, Calif -- A three-way NACA-USAF-USN Memorandum of Understanding, “Joint Project for a New High Speed Research Airplane,” was signed, opening the way for the X-15 program.
Despite the fact that it is one of the most celebrated experimental aircraft ever flown, most historical writings have always had a rather peculiar blind spot regarding the X-15 program. The citation for the 1961 Collier Trophy, for example, noted that the vehicle had made "invaluable technological contributions to the advancement of flight." It also commends "the great skill and courage" of its test pilots. In his letter nominating the program for the award earlier that same year, NASA Deputy Administrator Hugh L. Dryden struck the same general themes, albeit in greater detail:
To the X-15 Research Airplane Team, the scientists, engineers, technicians, and pilots of the National Aeronautics and Space Administration; the Department of Defense; and North American Aviation, Incorporated for the conception, design, development, construction, and flight operation of the X-15 research airplane, which contributed valuable research information in the supersonic and hypersonic speed regime up to the fringes of space, and who have thereby made an outstanding contribution to American leadership in aerospace science and technology and in the operation of manned space flight.
These two features —an outstanding piece of machinery, flown by exceptionally brave and proficient pilots— still stand as the primary legacy of the X-15. Certainly, all of this fame is well-deserved. Considering its technical achievements, as well as its contribution to knowledge about the upper atmosphere, hypersonics, high-altitude piloted flight, and so on, the X-15 clearly stands as one of the most successful research programs in the history of aviation. Similarly, the men who flew the craft into the fringes of space at six times the speed of sound proved themselves time and again to be extraordinary individuals. These elements of the program have been recognized repeatedly, with the X-15 and its members receiving sixteen awards in addition to the Collier Trophy.