Photos: Amazing X-Planes from the X-1 to XV-15

X-31 Enhanced Fighter Maneuverability Demonstrator

The X-31 Enhanced Fighter Maneuverability Demonstrator was used to test the newest technology in highly maneuverable fighters. The X-31 program logged an X-plane record of 580 flights during the program, 559 research missions and 21 in Europe for the 1995 Paris Air Show. This image was taken in March 1998.

X-33 Advanced Technology Demonstrator

However, due to technical problems with the composite liquid hydrogen tank, the X-33 program was cancelled in February 2001.

X-34 Technology Testbed Demonstrator

The unpiloted X-34 is a technology testbed demonstrator that is designed to demonstrate key vehicle and operational technologies applicable to future low-cost reusable launch vehicles. This image was taken July 20, 2000.

X-36 Tailless Fighter Agility Research Aircraft

The X-36 was built as a prototype remotely-piloted fighter jet without traditional tail surfaces. It first flew in 1997 and had 31 research flights since then. This image was taken on Oct. 30, 1997.

X-37 Advanced Technology Demonstrator

This artist's conception shows the X-37 Advanced Technology Demonstrator in the Shuttle Payload Bay. The aircraft is designed to test technologies for NASA's space plane program.

X-38 Crew Return Vehicle

The X-38 Crew Return Vehicle (CRV) research project is designed to test a prototype emergency crew return vehicle for the International Space Station. Flight research with the X-38 at Dryden began in 1997 and the aircraft has since completed eight flights. The program was terminated in 2002. This image of a drop test was taken Dec. 13, 2001.

X-40A Space Manuever Vehicle

The unpowered X-40A, a space maneuver vehicle, proved the capability of an autonomous flight control and landing system in a series of glide flights at NASA's Dryden Flight Research Center in California. The image was taken May 5, 2001.

X-43A Hypersonic Experimental Vehicle

The X-43A Hypersonic Experimental (Hyper-X) Vehicle hangs suspended in the cavernous Benefield Aenechoic Facility at Edwards Air Force Base in January 2000. The X-43A was developed to flight test a dual-mode ramjet/scramjet propulsion system at speeds from Mach 7 up to Mach 10.

X-45 Unmanned Combat Air Vehicle

The Boeing X-45A is being tested by the Joint Unmanned Combat Air Systems (J-UCAS) program as a weaponized unmanned vehicle. This image was taken on April 18, 2004 during a GPS-guided weapon demonstration flight.

X-48B in Flight

A joint NASA/Boeing team tested the X-48B Blended Wing Body aircraft at NASA's Dryden Flight Research Center. The team completed the 80th and last flight of the project's first phase on March 19, 2010.