This will mark the second space mission for the Air Force's X-37B space plane program — but the first for this particular plane. It is the second X-37B spacecraft built for the Air Force by Boeing and carries the name Orbital Test Vehicle 2, or OTV-2.Scramjet propelled hypersonic bombers are not that far away. The US won't need aircraft carriers anymore... Or pilots either!(...)
...The vehicle was originally developed as part of a NASA project that was shifted to the military when funding ran dry.(link)