Hypersonic Aircraft Doesn't Fly

The Air Force's unmanned craft had to be destroyed during a test

A hypersonic aircraft launched by the Air Force Tuesday spiraled out of control and was destroyed before it could reach its goal of speeding to 4,600 mph, Pentagon officials said Wednesday.

The third test of the X-51A Waverider was launched Tuesday off the California coast from a B-52 modified bomber aircraft and was to fly for 300 seconds, reaching hypersonic speeds of Mach 6, but only flew for 16 seconds, according to the Air Force.