The Space Shuttle orbiter was the reusable spaceplane component of the Space Shuttle program. Operated by NASA, the U.S. space agency, this vehicle could carry astronauts and payloads into low Earth orbit, perform in-space operations, then re-enter the atmosphere and land as a glider, returning its crew and any on-board payload to the Earth.

Six orbiters were built for flight: Columbia, Challenger, Discovery, Atlantis, Endeavourand Enterprise. All were built by the Pittsburgh, PA based Rockwell Internationalcompany in Palmdale, California. The first orbiter, Enterprise, made its maiden flight in 1977. An unpowered glider, it was carried by a modified Boeing 747 airliner called theShuttle Carrier Aircraft and released for a series of atmospheric test flights and landings. The remaining orbiters were fully operational spacecraft, and were launched vertically as part of the Space Shuttle stack. Enterprise was partially disassembled and retired after completion of critical testing.

Columbia was the first space-worthy orbiter, and made its inaugural flight in 1981.Challenger, Discovery, and Atlantis followed in 1983, 1984 and 1985 respectively. In 1986, Challenger was destroyed in an accident during launch. Endeavour was built asChallenger's replacement, and was first launched in 1992. In 2003, Columbia wasdestroyed during re-entry, leaving just three remaining orbiters. Discovery completed its final flight on March 9, 2011, and Endeavour completed its final flight on June 1, 2011.Atlantis completed the last ever Shuttle flight, STS-135, on July 21, 2011.

In addition to their crews and payloads, the reusable orbiter carried most of the Space Shuttle System's liquid-fueled rocket propulsion system, but both the liquid hydrogen fuel and the liquid oxygen oxidizer for its three main rocket engines were fed from an external cryogenic propellant tank. Additionally, two reusable solid rocket boosters provided additional thrust for approximately the first two minutes of launch. The orbiters themselves did carry hypergolic fuels used for their RCS thrusters and Orbital Maneuvering System engines.

Info: Space Shuttle Orbiter only wood (Discovery)