The Pentagon\'s latest test of hypersonic flight has a 25-foot unmanned vehicle trying to fly for 300 seconds at more than 4,500 mph, the U.S. Air Force said. The science fiction-like speed of Mach 6 is equivalent to an aircraft to flying from New York to London in less than an hour, CNN reported Tuesday. If all goes as planned, the latest test of the platypus-nosed X-51A Waverider will end with a dive into the Pacific Ocean Tuesday. X-51A sports an engine with virtually no moving parts and uses oxygen from the atmosphere for fuel. Dan Wasserbly of the military analysis publication IHS/Jane\'s said the military could use such an aircraft in two realms. \"They could use it to develop cruise missile-like weapons that could reach a target on the other side of the plant in minutes instead of hours, as well as developing aircraft which could put a quick-reaction force on a far-off battleground within hours instead of days,\" Wasserbly said. The Air Force and the Pentagon aren\'t saying much about the X-51A except that it was conceived in 2004. The kind of speeds X-51A is able to reach cannot be achieved with current jet-powered technology.