Space Shuttle
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This article is about the NASA Space Transportation System vehicle. For the associated program, see Space Shuttle program. For other shuttles and aerospace vehicles, see Spaceplane.
 Discovery lifts off at the start of STS-120. | |
| Function | Crewed orbital launch and reentry |
|---|---|
| Manufacturer | United Space Alliance Thiokol/Alliant Techsystems(SRBs) Lockheed Martin/Martin Marietta(ET) Boeing/Rockwell (orbiter) |
| Country of origin | United States of America |
| Project cost | US$ 209 billion (2010)[1][2][3] |
| Cost per launch | US$ 450 million (2011)[4] to 1.5 billion (2011)[2][3][5][6] |
| Size | |
| Height | 56.1 m (184.2 ft) |
| Diameter | 8.7 m (28.5 ft) |
| Mass | 2,030 t (4,470,000 lbm) |
| Stages | 2 |
| Capacity | |
| Payload to LEO | 27,500 kg (60,600 lb) |
| Payload to ISS | 16,050 kg (35,380 lb) |
| Payload to GTO | 3,810 kg (8,400 lb) |
| Payload to Polar orbit | 12,700 kg (28,000 lb) |
| Payload to Earth return | 14,400 kg (31,700 lb)[7] |
| Launch history | |
| Status | Retired (2011) |
| Launch sites | LC-39, Kennedy Space Center SLC-6, Vandenberg AFB(unused) |
| Total launches | 135 |
| Successes | 133 launches and landings |
| Failures | 2 Challenger (launch failure, 7 fatalities), Columbia (re-entry failure, 7 fatalities) |
| First flight | April 12, 1981 |
| Last flight | July 21, 2011 |
| Notable payloads | Tracking and Data Relay Satellites Spacelab Hubble Space Telescope Galileo, Magellan, Ulysses Mir Docking Module ISS components |
| Boosters - Solid Rocket Boosters | |
| No. boosters | 2[8] |
| Engines | 2 solid |
| Thrust | 12,500 kN (2,800,000 lbf) each, sea level liftoff |
| Specific impulse | 269 seconds (2.64 km/s) |
| Burn time | 124 s |
| Fuel | Solid (Ammonium perchlorate composite propellant) |
| First stage - Orbiter plus External Tank | |
| Engines | 3 SSMEs located on Orbiter |
| Thrust | 5,250 kN (1,180,000 lbf) total, sea level liftoff [9] |
| Specific impulse | 455 seconds (4.46 km/s) |
| Burn time | 480 s |
| Fuel | LOX/LH2 |
The Space Shuttle was a partially reusable low Earth orbital spacecraft system operated by the U.S. National Aeronautics and Space Administration (NASA). Its official program name was Space Transportation System (STS), taken from a 1969 plan for a system of reusable spacecraft of which it was the only item funded for development.[10] The first of four orbital test flights occurred in 1981, leading to operational flights beginning in 1982. They were used on a total of 135 missions from 1981 to 2011, launched from the Kennedy Space Center (KSC) in Florida. Operational missions launched numerous satellites, interplanetary probes, and theHubble Space Telescope (HST); conducted science experiments in orbit; and participated in construction and servicing of the International Space Station. The Shuttle fleet's total mission time was 1322 days, 19 hours, 21 minutes and 23 seconds.[11]
Shuttle components included the Orbiter Vehicle (OV), a pair of recoverable solid rocket boosters (SRBs), and the expendable external tank (ET) containing liquid hydrogen and liquid oxygen. The Shuttle was launched vertically, like a conventional rocket, with the two SRBs operating in parallel with the OV's three main engines, which were fueled from the ET. The SRBs were jettisoned before the vehicle reached orbit, and the ET was jettisoned just before orbit insertion, which used the orbiter's two Orbital Maneuvering System (OMS) engines. At the conclusion of the mission, the orbiter fired its OMS to de-orbit and re-enter the atmosphere. The orbiter glided to a runway landing on Rogers Dry Lake at Edwards Air Force Base in California or at the Shuttle Landing Facility at the KSC. After the landings at Edwards, the orbiter was flown back to KSC on the Shuttle Carrier Aircraft, a specially modified Boeing 747.
The first orbiter, Enterprise, was built for Approach and Landing Tests and had no orbital capability. Four fully operational orbiters were initially built: Columbia, Challenger, Discovery, and Atlantis. Of these, Challengerand Columbia were destroyed in mission accidents in 1986 and 2003 respectively, in which a total of fourteen astronauts were killed. A fifth operational orbiter, Endeavour, was built in 1991 to replace Challenger. The Space Shuttle was retired from service upon the conclusion of Atlantis 's final flight on July 21, 2011.
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