This test aircraft is a 90 percent scale version of what would later be designated the X-37B space plane. The Boeing Co., in partnership with the Air Force Research Laboratory, built the X-40A at Boeing’s Phantom Works facility at Seal Beach, California.
Boeing X-40A
The unmanned, unpowered Boeing X-40A was the first-phase flight test vehicle for the U.S. Air Force’s Space Maneuver Vehicle program that began in the late 1990s. The program aimed to develop small, reusable, highly maneuverable spacecraft for deploying satellites and conducting surveillance and logistics missions. On August 11, 1998, the X-40A made its first successful flight at Holloman AFB, New Mexico. Later, the USAF loaned the X-40A to NASA to test X-37 aerodynamics, guidance and other systems.