We have talked about the DARPA HTV-2 hypersonic glider that has been in testing before. The goal of the program is to be able to create a weapon that can strike anywhere on the planet within a few hours. The first test flight resulted in the loss of the HTV-2 about nine minutes into the flight and the aircraft was never found. The second test flight failed in the same phase of the flight. The second failure was further into the flight and was caused by different issues than the first flight failure according to DARPA.