Ultra-Fast Test Craft Crashes

It was supposed to be a step toward ultra-quick military strikes and maybe even passenger planes that could zip from coast to coast in under an hour. Instead, an unmanned hypersonic test craft crashed into the Pacific today shortly after being released from a B-52 bomber, reports AP. The Air Force craft, called an X-51A WaveRider, was designed to reach 3,600mph, but a faulty control fin prevented its "scramjet engine" from activating, according to the report. Mach 6 will have to wait, though Wired notes that this is the third such test failure, and "this time could be the last." (More Air Force stories.)