The launch culminates the project's long and expensive journey from NASA to the Pentagon's research and development arm and then to a secretive Air Force unit. Hundreds of millions of dollars have been spent on the X-37 program, but the current total has not been released. Built by Boeing's Phantom Works, the 11,000-pound craft is 9 feet tall and just over 29 feet long, with a wingspan of less than 15 feet. It has two angled tail fins rather than a single vertical stabilizer. Unlike the shuttle, it will be launched like a satellite, housed in a fairing atop an expendable Atlas V rocket, and deploy solar panels to provide electrical power in orbit.
The Air Force released only a general description of the mission objectives: testing of guidance, navigation, control, thermal protection and autonomous operation in orbit, re-entry and landing. The mission's length was not released, but the Air Force said the X-37B can stay in orbit for 270 days.