The Defense Advanced Research Projects Agency says an unmanned experimental aircraft lost contact with ground control on its second test flight. The Falcon HTV-2, designed to glide down from the upper atmosphere at 20 times the speed of sound, was launched from Vandenberg Air Force Base in California. The first part of the launch did go well. DARPA said they managed to collect some valuable information. This plane is able to fly anywhere in the world in less than 60 minutes.