The Boeing X-40 Space Maneuver Vehicle is a test platform for the Boeing X-37 reusable spaceplane, built by Boeing Phantom Works. It sought to test the X-37's systems in order to "reduce the cost and risk of future reusable space launch vehicle system".
History
The uncrewed X-40A was an 80%-90% subscale version of the Boeing X-37 reusable spaceplane, but lacking in propulsion or thermal protection systems. Boeing built the X-40A originally for the Air Force as part of that service’s Space Maneuver Vehicle program.
The aircraft was built at Boeing Phantom Works at Seal Beach, California, in partnership with the Air Force Research Laboratory.