13 April 1960: Major Robert M. White, USAF, made the first flight of an X-15 by an Air Force test pilot.
Carried aloft by a Boeing NB-52A Stratofortress, serial number 52-003, the first of three X-15 hypersonic research aircraft, 56-6670, was airdropped at 0915 above Rosamond Dry Lake. Major White ignited the two Reaction Motors XLR-11 rocket engines and with a burn time of 4 minutes, 13.7 seconds, the X-15 accelerated to Mach 1.9 (1,254 miles per hour/2,018 kilometers per hour) and reached 48,000 feet (14,630 meters). Both numbers were slightly short of the planned Mach 2.0 (1,320 miles per hour/2,124 kilometers per hour) and 50,000 feet (15,240 meters).
After 8 minutes, 52.7 seconds, Bob White and the X-15 touched down at Edwards Air Force Base.
Over the next 32 months Bob White made 16 flights in the X-15. He was the first pilot to fly faster than Mach 4, Mach 5 and Mach 6. He flew it to Mach 6.04, 4,093 miles per hour (6,587 kilometers per hour) and set a Fédération Aéronautique Internationale (FAI) altitude record of 314,750 feet (95,936 meters), for an altitude gain of 82,190 meters (269,652 feet).¹
White was one of three pilots awarded astronaut wings for his flights in the X-15.