Space Shuttle program
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This article is about the United States Space Shuttle program. For the Shuttle itself, see Space Shuttle. For information on the Soviet space shuttle program, see the article Buran program.
 Shuttle delivers P1 truss for International Space Station. | |
| 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 program, officially called the Space Transportation System (STS), was the United States government's manned launch vehicle program from 1981 to 2011, administered by NASA and officially beginning in 1972. The winged Space Shuttle orbiter—which was launched with two reusable solid rocket boosters and a disposable external fuel tank—usually carried four to seven astronauts (though crews as small as two and as large as eight have been carried) and up to 50,000 lb (22,700 kg) of payload into low Earth orbit (LEO). When its mission was complete, the Shuttle could independently move itself out of orbit using itsmaneuvering system and re-enter the Earth's atmosphere. During descent and landing the orbiter acted as a re-entry vehicle and a glider, using its reaction control system and flight control surfaces to maintain attitude until it made an unpowered landing at either Kennedy Space Center or Edwards Air Force Base.
The Shuttle is the only winged manned spacecraft to have achieved orbit and land, and the only reusable manned space vehicle that has ever made multiple flights into orbit (the Russian shuttle Buran was very similar and had the same capabilities but made only one unmanned spaceflight before it was cancelled). Its missions involved carrying large payloads to various orbits (including segments to be added to the International Space Station (ISS)), providing crew rotation for the space station, and performing service missions. The orbiter also recovered satellites and other payloads (e.g., from the ISS) from orbit and returned them to Earth, though its use in this capacity was rare. Each vehicle was designed with a projected lifespan of 100 launches, or 10 years' operational life, though original selling points on the shuttles were over 150 launches and over a 15-year operational span with a 'launch per month' expected at the peak of the program, but extensive delays in the development of the International Space Station [10] never created such a peak demand for frequent flights.
Although the concept had been explored since the late 1960s, the program formally commenced in 1972, and was the sole focus of NASA's manned operations after the final Apollo and Skylab flights in the mid-1970s. The Shuttle was originally conceived of and presented to the public in 1972 as a 'Space Truck' which would, among other things, be used to build a United States space station in low Earth orbit during the 1980s and then be replaced by a new vehicle by the early 1990s. The stalled plans for a U.S. space station evolved into the International Space Station and was formally initiated in 1983 by U.S. President Ronald Reagan, but the ISS suffered from long delays, design changes and cost over-runs [10] and forced the service life of the Space Shuttle to be extended several times until 2011 when it was finally retired — serving twice as long than it was originally designed to do. In 2004, according to the President George W. Bush's Vision for Space Exploration, use of the Space Shuttle was to be focused almost exclusively on completing assembly of the ISS, which was far behind schedule at that point.
The first experimental orbiter Enterprise was a high-altitude glider, launched from the back of a specially modified Boeing 747, only for initial atmospheric landing tests (ALT). Enterprise's first test flight was on February 18, 1977, only five years after the Shuttle program was formally initiated; leading to the launch of the first space-worthy shuttle Columbia on April 12, 1981 on STS-1. The Space Shuttle program finished with its last mission,STS-135 flown by Atlantis, in July 2011, retiring the final Shuttle in the fleet. The Space Shuttle program formally ended on August 31, 2011.[11]
Retirement of the Shuttle ended the era in which all of America's varied space activities were performed by one craft -or even one organization. Functions performed by the Shuttle for 30 years will be done by not one but many different spacecraft currently flying or in advanced development. Secret military missions are being flown by the US Air Force's "highly successful" unmanned mini-space plane, the X-37B[citation needed]. By 2012, cargo supply to the International Space Station began to be flown by privately owned commercial craft under NASA's Commercial Resupply Services by SpaceX's successfully tested and partially reusable Dragon spacecraft, followed by Orbital Sciences' Cygnus spacecraft in late 2013. Crew service to the ISS will be flown exclusively by the Russian Soyuz while NASA works on the Commercial Crew Development program. For missions beyond low Earth orbit, NASA is building the Space Launch System and the Orion spacecraft.
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