Make that 0 for 2. An unmanned hypersonic glider developed as part of U.S. defense research was lost Thursday after being launched atop a rocket and taking off to fly on its own. The experimental craft was designed as part of a U.S. military initiative to create technology that responds to threats at 20 times the speed of sound or greater. It was the second of two flights for Falcon Hypersonic Technology Vehicle-2, and contact was also lost with the first mission. During that flight the HTV-2 returned nine minutes of data, including 139 seconds of aerodynamic data at speeds between 17 and 22 times the speed of sound, DARPA said. No further details of the lost craft have been reported.