By Associated Press PUBLISHED: 22:37 EST, 3 May 2013 | UPDATED: 02:39 EST, 6 May 2013 An experimental unmanned aircraft developed for the U.S. Air Force went hypersonic during a recent test off the Southern California coast, flying at more than five times the speed of sound. The Air Force said Friday the X-51A WaveRider flew for more than three minutes under power from its exotic scramjet engine and hit a speed of Mach 5.1. The test on Wednesday marked the fourth and final flight of an X-51A by the Air Force, which has spent $300 million studying scramjet technology that it hopes can be used to deliver strikes around the globe within minutes.
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Craft could fly from London to New York in an hour
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WaveRider flew for more than three minutes under power from its exotic scramjet engine and hit a speed of Mach 5.1
The @placeholder traveled more than 230 miles in six minutes, making it the longest hypersonic flight of its kind.