Waverider Set to Surf Again

The Air Force’s second X-51A Waverider experimental hypersonic air vehicle is set to fly at the end of the month, aiming for speeds in excess of Mach 6, said Charles Brink, Air Force Research Lab’s X-51A program manager. “We plan to go fly the same profile that we tried to fly last time. . . . We met about 80 [percent] to 90 percent of our flight-test objectives and the [upcoming] flight will be to see if we can repeat the same success and move out further in the Mach regime,” Brink told reporters Tuesday during a teleconference. The X-51 is dropped from a B-52. An attached rocket is designed to fire for roughly 30 seconds before jettisoning, propelling the air vehicle to a speed where its supersonic combustion ramjet can engage. During the flight of the first X-51 last May, the initial sequence was successful before an anomaly forced termination at 143 seconds. Though the first test multiplied the standing scramjet flight record 10 times over, AFRL’s goal for the upcoming mission is a “nominal demonstrator flight of 240 seconds,” said Brink. Boeing and Pratt and Whitney Rocketdyne supply the X-51.