X-51A Sets Air-Breathing Hypersonic Record

The fourth and final mission of an X-51A Waverider test vehicle last week set the record for the longest ever air-breathing hypersonic flight, announced Air Force Research Lab officials. The May 1 flight over the Pacific Ocean was “a full mission success,” said Charlie Brink, the Air Force’s X-51A program manager, in the service’s May 3 release. The X-51 vehicle traveled more than 230 nautical miles in slightly more than six minutes off the coast of southern California, states the release. A B-52 starting from Edwards AFB, Calif., carried the X-51 aloft, releasing it at approximately 50,000 feet in altitude. The X-51’s rocket booster accelerated the vehicle to Mach 4.8. The vehicle then separated from the booster, whereupon its supersonic combustion ramjet engine ignited and propelled the vehicle to Mach 5.1 at 60,000 feet, according to the release. After its fuel supply was expended, the vehicle glided until it splashed down in the water. “I believe all we have learned from the X-51A Waverider will serve as the bedrock for future hypersonics research and ultimately the practical application of hypersonic flight,” said Brink. (Wright-Patterson report by Daryl Mayer) (See also Boeing release and X-51A Falls Short in Third Flight.)