May 01, 2013

The fourth and final mission of the Boeing X-51A WaveRider unmanned hypersonic vehicle sets the record for the longest ever air-breathing hypersonic flight. The X-51A traveled more than 230 nautical miles in slightly more than six minutes off the coast of southern California. A B-52 starting from Edwards AFB, Calif., carried the WaveRider aloft, releasing it at approximately 50,000 feet in altitude. The X-51’s rocket booster accelerated the vehicle to Mach 4.8, when the X-51 separated and ignited its supersonic combustion ramjet engine to propel itself to Mach 5.1 at 60,000 feet.