By Marina Malenic
The Air Force hopes to fly a hypersonic vehicle at Mach 6 for a record of four minutes next week, officials said yesterday.
The X-51 WaveRider reached Mach 5 when it flew for the first time in May 2010–at 143 minutes the longest flight of a supersonic combustion ramjet engine, or scramjet (Defense Daily, May 28, 2010).
“We definitely hope it will go longer next time,” said Charlie Brink, program manager with the Air Force Research Laboratory at Wright-Patterson AFB, Ohio. The second test is planned for March 22, Brink said during a Pentagon roundtable for bloggers and reporters.
As in last year’s test, the vehicle will be launched from a B-52 bomber flying over the Pacific Ocean Point Mugu Naval Air Warfare Center Sea Range. An Army Tactical Missile (ATACMS) solid rocket booster will then accelerate the vehicle before its own Pratt & Whitney Rocketdyne SJY61 engine ignites.
Pratt & Whitney is a division of United Technologies [UTX].
According to Brink, last year’s test flight was aborted early due to a faulty seal that allowed hot gases to build up inside the vehicle instead of being expelled through the back nozzle. He said Pratt & Whitney and vehicle prime contractor Boeing [BA] are making some changes to the nozzle interface to make it “much more robust,” potentially preventing the temperature and pressure buildup. He stressed that there was “no indication of sloppy workmanship or anything like that,” but that “the interface was not as strong or dimensionally tight as we thought.”
Pentagon officials have said they are studying the use of hypersonic weapons in applications such as Prompt Global Strike, a precision missile that could hit any target on earth within two hours. Brink said plans to weaponize the X-51 “is not currently in the program of record,” but future iterations of the design could move in that direction.
“We are going to work on the technologies that are in the X-51 to start transitioning those technologies to a more weapons-friendly design,” he said.
The program has produced four Waverider test vehicles and has $250 million in funding. The government’s contract with Boeing and Pratt & Whitney is worth $220 million, according to Brink, with the remainder going toward various testing expenses.
Hypersonic technology has potential applications in the fields of high-speed weapons, intelligence, surveillance and reconnaissance and space missions. Hypersonic speed describes velocities upward of Mach 5, or five times the speed of sound.