342376main_E-6682_full

NASA Flight Research Center (now NASA Armstrong Flight Research Center) research pilot Joseph A. Walker flew the first NASA flight in a North American X-15 rocket aircraft, tail number 56-6670. He reached Mach 2 at 48,630 ft. It was the ninth flight of the program; the preceding eight flights had been flown by Scott Crossfield for North American Aviation as part of the acceptance process.