| Space Shuttle | |
 Space Shuttle Atlantis on the launch pad prior to the STS-115 mission. | |
| Fact sheet | |
|---|---|
| Function | Manned partially re-usable launch and reentry system |
| Manufacturer | United Space Alliance: Thiokol/Boeing (SRBs) Lockheed Martin (Martin Marietta) - (ET) Rockwell International (orbiter) |
| Country of origin | United States of America |
| Size | |
| Height | 58.12 m (149.6 ft) |
| Diameter | 8.7 m (28.5 ft) |
| Mass | 2,029,203 kg (4,474,574 lb) |
| Stages | 2 |
| Capacity | |
| Payload to LEO | 24,400 kg (53,700 lb) |
| Payload to GTO | 3,810 kg (8,390 lb) |
| Launch History | |
| Status | Active |
| Launch sites | LC-39, Kennedy Space Center SLC-6, Vandenberg AFB (unused) |
| Total launches | 120 |
| Successes | 118 |
| Failures | 2 |
| Maiden flight | April 12, 1981 |
| Notable payloads | International Space Station components Hubble Space Telescope Galileo Magellan Chandra X-ray Observatory |
| Boosters (Stage 0) - Solid Rocket Boosters | |
| No boosters | 2 |
| Engines | 1 solid |
| Thrust | 2,800,000 lbf each, sea level liftoff (12.5 MN) |
| Specific impulse | 269 s |
| Burn time | 124 s |
| Fuel | solid |
| First Stage - External Tank | |
| Engines | (none) (3 SSMEs located on Orbiter) |
| Thrust | 1,180,000 lbf combined total, sea level liftoff (5.25 MN) |
| Specific impulse | 455 s |
| Burn time | 480 s |
| Fuel | LOX/LH2 |
| Second Stage - Orbiter | |
| Engines | 2 OME |
| Thrust | 12,000 lbf combined total vacuum thrust (53 kN) |
| Specific impulse | 316 s |
| Burn time | 1250 s |
| Fuel | MMH/N2O4 |
NASA's Space Shuttle, officially called Space Transportation System (STS), is the spacecraft currently used by the United States government for its human spaceflight missions. At launch, it consists of a rust-colored external tank (ET), two white, slender Solid Rocket Boosters (SRBs), and the orbiter, a winged spaceplane which is the space shuttle in the narrow sense.
The orbiter carries astronauts and payload such as satellites or space station parts into low earth orbit, into the Earth's upper atmosphere or thermosphere.[1] Usually, five to seven crew members ride in the orbiter. The payload capacity is 50,000 lb (22,700 kg). When the orbiter's mission is complete it fires its Orbital Maneuvering System (OMS) thrusters to drop out of orbit and re-enters the lower atmosphere.[1] During the descent and landing, the shuttle orbiter acts as a glider, and makes a completely unpowered ("dead stick") landing.
The shuttle is the first orbital spacecraft designed for partial reusability. It carries payloads to low Earth orbit, provides crew rotation for the International Space Station (ISS), and performs servicing missions. The orbiter can also recover satellites and other payloads from orbit and return them to Earth, but this capacity has not been used often. However, it has been used to return large payloads from the ISS to Earth, as the Russian Soyuz spacecraft has limited capacity for return payloads. Each Shuttle was designed for a projected lifespan of 100 launches or 10 years' operational life. The man responsible for the design of the STS was Maxime Faget, who had also overseen the Mercury, Gemini and Apollo spacecraft designs. The crucial factor in the size and shape of the Shuttle Orbiter was the requirement that it be able to accommodate the largest planned spy satellites, and have the cross-range recovery range to meet classified USAF missions requirement for a one-around abort for a polar launch. Factors involved in opting for 'reusable' solid rockets and an expendable fuel tank included the desire of the Pentagon to obtain a high-capacity payload vehicle for satellite deployment, and the desire of the Nixon administration to reduce the costs of space exploration by developing a spacecraft with reusable components.
Six shuttles have been built; the first orbiter, Enterprise, was not built for actual space flight, and was used only for testing purposes. Five space-worthy orbiters were built: Columbia, Challenger, Discovery, Atlantis, and Endeavour. Challenger disintegrated 73 seconds after launch in 1986, and Endeavour was built as a replacement. Columbia broke apart during re-entry in 2003.
In 2004, NASA announced that the Space Shuttle would be retired in 2010, and from 2014 on, would be replaced by the Orion, a new vehicle that is designed to take humans to the Moon and beyond.
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Description
Shuttles are each a partially reusable launch system composed of three main assemblies: the reusable Orbiter vehicle (OV), the expendable external tank (ET), and the two partially-reusable solid rocket boosters (SRBs). The tank and boosters are jettisoned during ascent; only the orbiter goes into orbit. The vehicle is launched vertically like a conventional rocket, and the orbiter glides to a horizontal landing, after which it is refurbished for reuse.
At times, the orbiter itself is referred to as the space shuttle. Technically, this is a misnomer, as the actual "Space Transportation System" (space shuttle) is the combination of the orbiter, the external tank (ET), and the two partially-reusable solid rocket boosters. Combined, these are referred to as the "Stack".
Orbiter vehicle
The orbiter resembles an aircraft with double-delta wings, swept 81° at the inner leading edge, and 45° at the outer leading edge. Its vertical stabilizer's leading edge is swept back at a 50° angle. The four elevons, mounted at the trailing edge of the wings, and the rudder/speed brake, attached at the trailing edge of the stabilizer, with the body flap, control the orbiter during descent and landing. The orbiter has a large payload bay measuring 15 feet by 60 feet (4.6 m × 18.3 m) comprising most of the fuselage.
Three Space Shuttle Main Engines (SSMEs) are mounted on the orbiter's aft fuselage in a triangular pattern. The three engines can swivel 10.5 degrees up and down, and 8.5 degrees from side to side during ascent to change the direction of their thrust and steer the shuttle as well as push. The orbiter structure is made primarily from aluminum alloy, although the engine thrust structure is made from titanium (alloy) Solid Rocket Boosters
Two solid rocket boosters (SRBs) each provide 2.8 million lbf (12.5 MN) of thrust at liftoff, which is 83% of the total thrust needed for liftoff. The SRBs are jettisoned two minutes after launch at a height of about 150,000 feet (45.7 km), and then deploy parachutes and land in the ocean to be recovered. The SRB cases are made of steel about ½ inch (13 mm) thick.[2]
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