X-38 is the designation of a prototype for an unpowered aerodynamic lifting body, which should allow the emergency evacuation of the International Space Station ( ISS). Such a slider is referred to as Crew Return Vehicle ( CRV).

The plans before saw to let the glider permanently docked at the space station. In an emergency, the crew would have risen in the X - 38 would have decoupled from the ISS and leave the orbit. Equipped with a heat shield glider would have occurred in the Earth's atmosphere and been slowed down by air resistance. In the near-Earth atmospheric layers a gradually unfolded glider ( ' parafoil ') had his team, gliders and ensures a safe and soft landing on the mainland. Normally, this landing was due to expire automatically, because it was expected to have to ascribe injured crew members.

X-38 should not have a stand-alone drive, but only via control functions through a run with nitrogen nozzle system and a pair of rear remote valves, which consist because of the high temperature stress during re-entry, as well as other heat shield components ( nose cap, Fügelvorderkanten ), completely made ​​of fiber- reinforced ceramics.

Until the planned implementation of this project as a rescue capabilities of the space station Soyuz spaceships were provided.

As a model for the development of the X-38 project X - 24 of the United States Air Force / NASA was included. The special construction methods, inter alia, the X-38 is called Lifting Body (dynamic buoyancy ).

The European contribution to the development was the construction of the rear fuselage structure ( ' aft structure ') according to the guidelines of NASA. The structural concept of a metallic skeleton with a partial bearing planking turned out to be not sufficiently efficient, leading to multiple adaptation of the mass of the vehicle and as a result, to iterations on the parafoil as well as the thermal protection.

The first flight took place on 12 March 1998. After seven flights of the last flight took place on 13 December 2001. The project X-38 was stopped for lack of funding in March 2002. A model with 80 % of the original size was tested on a B- 52 flight model for the orbital flight but not completed. This causes a restriction on the size of the crew in the space station astronauts and cosmonauts on six, because a maximum of two Soyuz space ships can be docked for three astronauts to the ISS. With the X -38 could have up to seven people can be evacuated.

One of the X-38 prototype is on display at the Strategic Air and Space Museum in Ashland, Nebraska.

The concept of dynamic lift body was also taken up by the company SpaceDev under the COTS program of NASA and led to the present ( 2013) under development manned space shuttle Dream Chaser.