On June 11, 1951, the Douglas D-558-II Skyrocket, flown by company test pilot Bill Bridgeman, set new unofficial airplane speed and altitude records at Edwards Air Force Base, California, with a speed estimated at more than 1,200 mph and an altitude estimated at 70,000 feet. The Skyrocket was a single-seat, swept-wing research aircraft powered by both a turbojet engine and a rocket motor.