US military loses contact with hypersonic aircraft
US military scientists lost contact with an unmanned hypersonic experimental aircraft on its second test flight, officials said.
The Falcon Hypersonic Test Vehicle 2 (HTV-2) successfully separated from its rocket but lost contact shortly into its “glide phase”.
The plane is designed to travel at Mach 20, or 20 times the speed of sound …. http://www.bbc.co.uk