Fifty-seven years ago this month, USAF Major Robert M. White flew the North American X-15 hypersonic research aircraft to a record altitude of 314,750 feet (51.8 nautical miles). In doing so, he became the first X-15 pilot to be awarded USAF Astronaut Wings.
The North American X-15 was the first manned hypersonic aircraft. It was designed, engineered, constructed and first flown in the 1950′s. As originally conceived, the X-15 was designed to reach 4,000 mph (Mach 6) and 250,000 feet. Before its flight test career was over, the type would meet and exceed both performance goals.
North American built a trio of X-15 airframes; Ship No. 1 (S/N 56-6670), Ship No. 2 (56-6671) and Ship No. 3 (56-6672). The X-15 measured 50 feet in length, had a wing span of 22 feet and a GTOW of 33,000 lbs. Ship No. 2 would later be modified to the X-15A-2 enhanced performance configuration. The X-15A-2 had a length of 52.5 feet and a GTOW of around 56,000 lbs.
The Reaction Motors XLR-99 rocket engine powered the X-15. Small, but mighty, the XLR-99 generated 57,000 pounds of sea level thrust at full-throttle. It weighed only 910 pounds. The XLR-99 used anhydrous ammonia and LOX as propellants. Burn time varied between 83 seconds for the stock X-15 and about 150 seconds for the X-15A-2.
The X-15 was carried to drop conditions (typically Mach 0.8 at 42,000 feet) by a B-52 mothership. A pair of aircraft were used for this purpose; a B-52A (S/N 52-003) and a B-52B (S/N 52-008). Once dropped from the mothership, the X-15 pilot lit the XLR-99 to accelerate the aircraft. The X-15A-2 also carried a pair of drop tanks which provided propellants for a longer burn time than was possible with the stock X-15 flight.
The X-15 employed both aerodynamic and reaction flight controls. The latter were required to maintain vehicle attitude in space-equivalent flight. The X-15 pilot wore a full-pressure suit in consequence of the aircraft’s extreme altitude capability. The typical X-15 drop-to-landing flight duration was on the order of 10 minutes. All X-15 landings were performed dead-stick.
On Tuesday, 17 July 1962, Bob White flew his 15th X-15 mission. The X-15 and White had already become the first aircraft-pilot duo to hit Mach 4, 5 and 6. On this particular day, White was at the controls of X-15 Ship No. 3. It was the 62nd flight research mission of the X-15 Program with a target maximum altitude of 282,000 feet.
At 09:31:10 UTC, X-15 Ship No. 3 was launched from the B-52B mothership commanded by USAF Captain Jack Allavie. White lit the XLR-99 and pulled into a steep climb. His hypersonic steed rapidly gained altitude. Burnout of the XLR-99 occurred 82 seconds after ignition; 2.0 seconds longer than planned. At this point, White was traveling at 3,832 mph or Mach 5.45. Following an uneventful climb to apogee and a expertly-flown reentry, White touched-down safely on Rogers Dry Lake at 09:41:30 UTC. His reaction to the entire experience was succinctly expressed when he exclaimed, “Boy, that was a ride!”
The extra impulse provided by the longer-than-planned burn of the XLR-99 rocket engine drove White’s X-15 more than 32,000 feet higher than planned. The resulting apogee of 314,750 feet established a still-standing FAI world altitude record for piloted aircraft. The occasion also marked the first time that the X-15 flew higher than 300,000 feet. For flying beyond 50 statute miles (264,000 feet), Bob White received USAF Astronaut Wings; the first X-15 pilot to be awarded such.
Bob White piloted the X-15 a total of sixteen (16) times. He was one (1) of only twelve (12) men to fly the aircraft. White left X-15 Program and Edwards AFB in 1963. He went on to serve his country in numerous capacities as a member of the Air Force including flying 70 combat missions in Viet Nam. He returned to Edwards AFB as AFFTC Commander in August of 1970.
Major General Robert M. White retired from the United States Air Force in 1981. During his period of military service, he received numerous decorations and awards including the Air Force Cross, Distinguished Service Medal, Silver Star with three oak leaf clusters, Legion of Merit, Distinguished Flying Cross with four oak leaf clusters, Bronze Star Medal, and Air Medal with 16 oak leaf clusters.
Bob White was a true American hero. He was one of those heroes who neither sought nor received much notoreity for his accomplishments. He served his country and the aviation profession well. Bob White’s final flight occurred on Wednesday, 17 March 2010. He was 85 years of age.