The X-37 will be NASA’s first X-vehicle demonstrator to operate during both the orbital and re-entry phases of flight. The robotic space plane, which is a 120 percent scale derivative of the Air Force's X-40A, will play a key role in NASA’s effort to dramatically cut the cost of putting payloads into space.

The X-37 will be ferried to orbit by the Space Shuttle or an expendable launch vehicle where it will be deployed.  The vehicle will then remain in orbit for up to 21 days and perform a variety of experiments before re-entering the atmosphere and landing on a conventional runway.  The design requirement for the vehicle is 20 flights and landings, but only two are currently scheduled by NASA.

The X-37 will demonstrate 41 advanced airframe, propulsion and operations technologies that can support various launch vehicle and spacecraft designs. A major focus of the X-37 will seek improvement of today’s spacecraft thermal protection systems. The systems now in use are fragile and expensive to maintain.

The X-37, which is being built by The Boeing Company, will be powered by a single AR-2/3 hydrogen peroxide and JP-10 (jet fuel) engine.  The vehicle will also have an internal seven by four foot payload bay to house up to 500 pounds of experiments.  Unpowered atmospheric tests are scheduled for 2001 with the first orbital flight planned for 2002.