A third Boeing X-51 hypersonic test vehicle will fly shortly, a senior company official says.

"We're planning to fly another vehicle shortly," says Joe Vogel, Boeing's hypersonics director. The test vehicle will fly as soon as the government gives its assent. "It'll be this year."

That would be the missile-like test vehicle's third flight. Two earlier tests successfully demonstrated hypersonic flight, but the air vehicles did not fly for as long a duration as was expected.

"I consider it successful," Vogel says of the truncated previous flights.

Vogel notes that the first flight set a world record for duration at hypersonic speed while the second flight ended with a controlled landing into the ocean.

There is also a fourth test vehicle available to the programme. If the third flight proves to be completely successful, that remaining test article could be used for materials testing or testing different flight profiles, Vogel says.

Boeing is working on the supersonic combustion ram jet, or scramjet, with the Defense Advanced Research Projects Agency (DARPA), US Air Force Research Laboratory and Pratt and Whitney Rocketdyne.

If successful, the endeavor could yield new missiles, aircraft and space-launch vehicles, Vogel says. A flight from New York to Los Angeles could take less 39 minutes at Mach 5, he adds.

Source: Flight International