Space Shuttle

Space Shuttle

Overview
The Space Shuttle was a manned orbital rocket and spacecraft system operated by NASA on 135 missions from 1981 to 2011. The system combined rocket launch, orbital spacecraft, and re-entry spaceplane
Spaceplane
A spaceplane is a vehicle that operates as an aircraft in Earth's atmosphere, as well as a spacecraft when it is in space. It combines features of an aircraft and a spacecraft, which can be thought of as an aircraft that can endure and maneuver in the vacuum of space or likewise a spacecraft that...

 with modular add-ons. Major missions included launching numerous satellites and interplanetary probes, conducting space science experiments, and 37 missions constructing and servicing the International Space Station
International Space Station
The International Space Station is a habitable, artificial satellite in low Earth orbit. The ISS follows the Salyut, Almaz, Cosmos, Skylab, and Mir space stations, as the 11th space station launched, not including the Genesis I and II prototypes...

. A major international contribution was the Spacelab
Spacelab
Spacelab was a reusable laboratory used on certain spaceflights flown by the Space Shuttle. The laboratory consisted of multiple components, including a pressurized module, an unpressurized carrier and other related hardware housed in the Shuttle's cargo bay...

 payload suite, from the ESA
European Space Agency
The European Space Agency , established in 1975, is an intergovernmental organisation dedicated to the exploration of space, currently with 18 member states...

.

Major components included the orbiters
Space Shuttle Orbiter
The Space Shuttle orbiter was the orbital spacecraft of the Space Shuttle program operated by NASA, the space agency of the United States. The orbiter was a reusable winged "space-plane", a mixture of rockets, spacecraft, and aircraft...

, recoverable boosters
Space Shuttle Solid Rocket Booster
The Space Shuttle Solid Rocket Boosters were the pair of large solid rockets used by the United States' NASA Space Shuttle during the first two minutes of powered flight. Together they provided about 83% of liftoff thrust for the Space Shuttle. They were located on either side of the rusty or...

, external tanks
Space Shuttle external tank
A Space Shuttle External Tank is the component of the Space Shuttle launch vehicle that contains the liquid hydrogen fuel and liquid oxygen oxidizer. During lift-off and ascent it supplies the fuel and oxidizer under pressure to the three Space Shuttle Main Engines in the orbiter...

, payloads, and supporting infrastructureorchestrated by thousands of people on the ground and crewed by an elite cadre of astronauts.

The Space Shuttle was a partially reuseable launch system and orbital spacecraft
Spacecraft
A spacecraft or spaceship is a craft or machine designed for spaceflight. Spacecraft are used for a variety of purposes, including communications, earth observation, meteorology, navigation, planetary exploration and transportation of humans and cargo....

 operated by the U.S.
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Timeline

1972   U.S. President Richard Nixon orders the development of a space shuttle program.

1976   The first Space Shuttle, Enterprise, is unveiled by NASA.

1979   The first fully functional space shuttle orbiter, ''Columbia'', is delivered to the John F. Kennedy Space Center to be prepared for its first launch.

1981   The first launch of a Space Shuttle: ''Columbia'' launches on the STS-1 mission. thumb

1982   NASA's Space Shuttle ''Columbia'', is launched from the Kennedy Space Center on its third mission, STS-3.

1982   Space Shuttle Columbia launched from the Kennedy Space Center on the final research and development flight mission, STS-4.

1983   During STS-6, astronauts Story Musgrave and Don Peterson perform the first space shuttle spacewalk.

1984   STS-41-D: The Space Shuttle ''Discovery'' takes off on its maiden voyage.

1984   Marc Garneau becomes the first Canadian in space, aboard the Space Shuttle ''Challenger''.

1988   The PEPCON disaster rocks Henderson, Nevada, as tons of space shuttle fuel detonates during a fire.

 
Encyclopedia
The Space Shuttle was a manned orbital rocket and spacecraft system operated by NASA on 135 missions from 1981 to 2011. The system combined rocket launch, orbital spacecraft, and re-entry spaceplane
Spaceplane
A spaceplane is a vehicle that operates as an aircraft in Earth's atmosphere, as well as a spacecraft when it is in space. It combines features of an aircraft and a spacecraft, which can be thought of as an aircraft that can endure and maneuver in the vacuum of space or likewise a spacecraft that...

 with modular add-ons. Major missions included launching numerous satellites and interplanetary probes, conducting space science experiments, and 37 missions constructing and servicing the International Space Station
International Space Station
The International Space Station is a habitable, artificial satellite in low Earth orbit. The ISS follows the Salyut, Almaz, Cosmos, Skylab, and Mir space stations, as the 11th space station launched, not including the Genesis I and II prototypes...

. A major international contribution was the Spacelab
Spacelab
Spacelab was a reusable laboratory used on certain spaceflights flown by the Space Shuttle. The laboratory consisted of multiple components, including a pressurized module, an unpressurized carrier and other related hardware housed in the Shuttle's cargo bay...

 payload suite, from the ESA
European Space Agency
The European Space Agency , established in 1975, is an intergovernmental organisation dedicated to the exploration of space, currently with 18 member states...

.

Major components included the orbiters
Space Shuttle Orbiter
The Space Shuttle orbiter was the orbital spacecraft of the Space Shuttle program operated by NASA, the space agency of the United States. The orbiter was a reusable winged "space-plane", a mixture of rockets, spacecraft, and aircraft...

, recoverable boosters
Space Shuttle Solid Rocket Booster
The Space Shuttle Solid Rocket Boosters were the pair of large solid rockets used by the United States' NASA Space Shuttle during the first two minutes of powered flight. Together they provided about 83% of liftoff thrust for the Space Shuttle. They were located on either side of the rusty or...

, external tanks
Space Shuttle external tank
A Space Shuttle External Tank is the component of the Space Shuttle launch vehicle that contains the liquid hydrogen fuel and liquid oxygen oxidizer. During lift-off and ascent it supplies the fuel and oxidizer under pressure to the three Space Shuttle Main Engines in the orbiter...

, payloads, and supporting infrastructureorchestrated by thousands of people on the ground and crewed by an elite cadre of astronauts.

Overview


The Space Shuttle was a partially reuseable launch system and orbital spacecraft
Spacecraft
A spacecraft or spaceship is a craft or machine designed for spaceflight. Spacecraft are used for a variety of purposes, including communications, earth observation, meteorology, navigation, planetary exploration and transportation of humans and cargo....

 operated by the U.S. National Aeronautics and Space Administration (NASA) for human spaceflight
Human spaceflight
Human spaceflight is spaceflight with humans on the spacecraft. When a spacecraft is manned, it can be piloted directly, as opposed to machine or robotic space probes and remotely-controlled satellites....

 missions from 1981 to 2011. The system combined rocket launch, orbital spacecraft, and re-entry spaceplane
Spaceplane
A spaceplane is a vehicle that operates as an aircraft in Earth's atmosphere, as well as a spacecraft when it is in space. It combines features of an aircraft and a spacecraft, which can be thought of as an aircraft that can endure and maneuver in the vacuum of space or likewise a spacecraft that...

 with modular add-ons. The first
STS-1
STS-1 was the first orbital flight of NASA's Space Shuttle program. Space Shuttle Columbia launched on 12 April 1981, and returned to Earth on 14 April, having orbited the Earth 37 times during the 54.5-hour mission. It was the first American manned space flight since the Apollo-Soyuz Test Project...

 of four orbital test flights occurred in 1981 leading to operational flights beginning in 1982, all launched from the Kennedy Space Center, Florida. The system was retired from service in 2011 after 135 missions; on July 8, 2011, with Space Shuttle Atlantis performing that 135th launch - the final launch of the three-decade shuttle program. The program ended after Atlantis landed at the Kennedy Space Center on July 21, 2011. Major missions included launching numerous satellites and interplanetary probes, conducting space science experiments, and servicing and construction of space stations. Enterprise
Space Shuttle Enterprise
The Space Shuttle Enterprise was the first Space Shuttle orbiter. It was built for NASA as part of the Space Shuttle program to perform test flights in the atmosphere. It was constructed without engines or a functional heat shield, and was therefore not capable of spaceflight...

was a prototype orbiter
Space Shuttle Orbiter
The Space Shuttle orbiter was the orbital spacecraft of the Space Shuttle program operated by NASA, the space agency of the United States. The orbiter was a reusable winged "space-plane", a mixture of rockets, spacecraft, and aircraft...

 used for atmospheric testing during development in the 1970s, and lacked engines and heat shield. Five space-worthy orbiters
Space Shuttle Orbiter
The Space Shuttle orbiter was the orbital spacecraft of the Space Shuttle program operated by NASA, the space agency of the United States. The orbiter was a reusable winged "space-plane", a mixture of rockets, spacecraft, and aircraft...

 were built—two were destroyed in accidents and the others have been retired.

It was used for orbital space missions by NASA, the U.S. Department of Defense, the European Space Agency
European Space Agency
The European Space Agency , established in 1975, is an intergovernmental organisation dedicated to the exploration of space, currently with 18 member states...

, Japan, and Germany. The United States funded Space Transportation System
Space Transportation System
The Space Transportation System is another name for the NASA Space Shuttle and Space Shuttle program. However, the name originates from, and can describe a more elaborate set of spacefaring hardware in the 1970s, although this meaning is obscure...

 (STS) development and shuttle operations except for Spacelab D1
STS-61-A
STS-61-A was the 22nd mission of NASA's Space Shuttle program. It was a scientific Spacelab mission, funded and directed by West Germany – hence the non-NASA designation of D-1 . STS-61-A was the last successful mission of the Space Shuttle Challenger, which was destroyed during STS-51-L in 1986...

 and D2
STS-55
-Backup crew:-Mission parameters:*Mass:**Orbiter landing with payload: **Payload: *Perigee: *Apogee: *Inclination: 28.5°*Period: 90.7 min-Mission highlights:...

sponsored by West Germany
West Germany
West Germany is the common English, but not official, name for the Federal Republic of Germany or FRG in the period between its creation in May 1949 to German reunification on 3 October 1990....

 and reunified Germany
German reunification
German reunification was the process in 1990 in which the German Democratic Republic joined the Federal Republic of Germany , and when Berlin reunited into a single city, as provided by its then Grundgesetz constitution Article 23. The start of this process is commonly referred by Germans as die...

 respectively. In addition, SL-J
STS-47
STS-47 was the 50th Space Shuttle mission of the program, as well as the second mission of Space Shuttle Endeavour. The mission mainly involved conducting experiments in life and material sciences.-Crew:-Backup crew:-Mission parameters:* Mass:...

 was partially funded by Japan.

At launch, it consisted of the "stack", including a dark orange-colored external tank
Space Shuttle external tank
A Space Shuttle External Tank is the component of the Space Shuttle launch vehicle that contains the liquid hydrogen fuel and liquid oxygen oxidizer. During lift-off and ascent it supplies the fuel and oxidizer under pressure to the three Space Shuttle Main Engines in the orbiter...

 (ET); two white, slender Solid Rocket Boosters
Space Shuttle Solid Rocket Booster
The Space Shuttle Solid Rocket Boosters were the pair of large solid rockets used by the United States' NASA Space Shuttle during the first two minutes of powered flight. Together they provided about 83% of liftoff thrust for the Space Shuttle. They were located on either side of the rusty or...

 (SRBs); and the Orbiter Vehicle
Space Shuttle Orbiter
The Space Shuttle orbiter was the orbital spacecraft of the Space Shuttle program operated by NASA, the space agency of the United States. The orbiter was a reusable winged "space-plane", a mixture of rockets, spacecraft, and aircraft...

 (OV), which contained the crew and payload. Some payloads were launched into higher orbits with either of two different booster stages developed for the STS (single-stage Payload Assist Module
Payload Assist Module
frame|PAM-D with the [[Phoenix |Phoenix]] spacecraft. The [[Star 48|Star 48-B]] engine is shown being spun, fired, [[Yo-yo de-spin|yo-yo de-spun]] and jettisoned.thumb|SBS-3 satellite with PAM-D stage inside the space shuttle...

 or two-stage Inertial Upper Stage
Inertial Upper Stage
The Inertial Upper Stage , originally known as the Interim Upper Stage, is a two-stage solid-fueled booster rocket developed by the U.S...

). The Space Shuttle was stacked in the Vehicle Assembly Building
Vehicle Assembly Building
The Vehicle Assembly Building, or VAB, at NASA's Kennedy Space Center was used to assemble and house American manned launch vehicles from 1968-2011. It is the fourth largest building in the world by volume...

 and the stack mounted on a mobile launch platform held down by four explosive bolts
Pyrotechnic fastener
A pyrotechnic fastener is a fastener, usually a nut or bolt, that incorporates a pyrotechnic charge that can be initiated remotely. One or more explosive charges embedded within the bolt are typically activated by an electric current, and the charge breaks the bolt into two or more pieces...

 on each SRB which are detonated at launch.

The shuttle stack launched vertically like a conventional rocket. It lifted off under the power of its two SRBs and three main engines
Space Shuttle main engine
The RS-25, otherwise known as the Space Shuttle Main Engine , is a reusable liquid-fuel rocket engine built by Pratt & Whitney Rocketdyne for the Space Shuttle, running on liquid hydrogen and oxygen. Each Space Shuttle was propelled by three SSMEs mated to one powerhead...

, which were fueled by liquid hydrogen and liquid oxygen from the external tank. The Space Shuttle had a two-stage ascent. The SRBs provided additional thrust during liftoff and first-stage flight. About two minutes after liftoff, explosive bolts were fired, releasing the SRBs, which then parachuted into the ocean, to be retrieved by ships
NASA recovery ship
-References:...

 for refurbishment and reuse. The shuttle orbiter and external tank continued to ascend on an increasingly horizontal flight path under power from its main engines. Upon reaching 17,500 mph (7.8 km/s), necessary for low Earth orbit
Low Earth orbit
A low Earth orbit is generally defined as an orbit within the locus extending from the Earth’s surface up to an altitude of 2,000 km...

, the main engines were shut down. The external tank was then jettisoned to burn up in the atmosphere. After jettisoning the external tank, the orbital maneuvering system (OMS) engines were used to adjust the orbit.

The orbiter carried people
Astronaut
An astronaut or cosmonaut is a person trained by a human spaceflight program to command, pilot, or serve as a crew member of a spacecraft....

 and payload such as satellites or space station parts into low Earth orbit, into the Earth's upper atmosphere or thermosphere
Thermosphere
The thermosphere is the biggest of all the layers of the Earth's atmosphere directly above the mesosphere and directly below the exosphere. Within this layer, ultraviolet radiation causes ionization. The International Space Station has a stable orbit within the middle of the thermosphere, between...

. Usually, five to seven crew members rode in the orbiter. Two crew members, the commander and pilot, were sufficient for a minimal flight, as in the first four "test" flights, STS-1 through STS-4. The typical payload capacity was about 22700 kilograms (50,044.9 lb), but could be increased depending on the choice of launch configuration. The orbiter carried its payload in a large cargo bay with doors that opened along the length of its top, a feature which made the Space Shuttle unique among spacecraft. This feature made possible the deployment of large satellites such as the Hubble Space Telescope
Hubble Space Telescope
The Hubble Space Telescope is a space telescope that was carried into orbit by a Space Shuttle in 1990 and remains in operation. A 2.4 meter aperture telescope in low Earth orbit, Hubble's four main instruments observe in the near ultraviolet, visible, and near infrared...

, and also the capture and return of large payloads back to Earth.

When the orbiter's space mission was complete, it fired its OMS thrusters to drop out of orbit and re-enter
Atmospheric reentry
Atmospheric entry is the movement of human-made or natural objects as they enter the atmosphere of a celestial body from outer space—in the case of Earth from an altitude above the Kármán Line,...

 the lower atmosphere. During descent, the orbiter passed through different layers of the atmosphere and decelerates from hypersonic
Hypersonic
In aerodynamics, a hypersonic speed is one that is highly supersonic. Since the 1970s, the term has generally been assumed to refer to speeds of Mach 5 and above...

 speed primarily by aerobraking
Aerobraking
Aerobraking is a spaceflight maneuver that reduces the high point of an elliptical orbit by flying the vehicle through the atmosphere at the low point of the orbit . The resulting drag slows the spacecraft...

. In the lower atmosphere and landing phase, it was more like a glider
Glider aircraft
Glider aircraft are heavier-than-air craft that are supported in flight by the dynamic reaction of the air against their lifting surfaces, and whose free flight does not depend on an engine. Mostly these types of aircraft are intended for routine operation without engines, though engine failure can...

 but with reaction control system
Reaction control system
A reaction control system is a subsystem of a spacecraft whose purpose is attitude control and steering by the use of thrusters. An RCS system is capable of providing small amounts of thrust in any desired direction or combination of directions. An RCS is also capable of providing torque to allow...

 (RCS) thrusters and fly-by wire-controlled hydraulically-actuated flight surfaces controlling its descent. It landed on a long runway as a spaceplane. The aerodynamic shape was a compromise between the demands of radically different speeds and air pressures during re-entry, hypersonic flight, and subsonic atmospheric flight. As a result, the orbiter had a relatively high sink rate at low altitudes, and it transitioned during re-entry from using RCS thrusters at very high altitudes to flight surfaces in the lower atmosphere.

Early history


The formal design of what became the Space Shuttle began with "Phase A" contract design studies issued in the late 1960s. However, conceptualization began two decades earlier, before the Apollo program of the 1960s. One of the places the concept of a spacecraft returning from space to a horizontal landing originated was within NACA
NACA
- Organizations :* National Advisory Committee for Aeronautics, the forerunner of the U.S. federal agency NASA* National Association for Campus Activities, an organization for programmers of university and college activities...

, in 1954, in the form of an aeronautics
Aeronautics
Aeronautics is the science involved with the study, design, and manufacturing of airflight-capable machines, or the techniques of operating aircraft and rocketry within the atmosphere...

 research experiment later named the X-15
North American X-15
The North American X-15 rocket-powered aircraft/spaceplane was part of the X-series of experimental aircraft, initiated with the Bell X-1, that were made for the USAAF/USAF, NACA/NASA, and the USN. The X-15 set speed and altitude records in the early 1960s, reaching the edge of outer space and...

. The NACA proposal was submitted by Walter Dornberger
Walter Dornberger
Major-General Dr Walter Robert Dornberger was a German Army artillery officer whose career spanned World Wars I and II. He was a leader of Germany's V-2 rocket program and other projects at the Peenemünde Army Research Center....

.

In 1958, the X-15 concept further developed into proposal to launch a X-15 into space, and another X-series
X-plane
The X-planes are a series of experimental United States airplanes and helicopters used for the testing and evaluation of new technologies and aerodynamic concepts...

 spaceplane
Spaceplane
A spaceplane is a vehicle that operates as an aircraft in Earth's atmosphere, as well as a spacecraft when it is in space. It combines features of an aircraft and a spacecraft, which can be thought of as an aircraft that can endure and maneuver in the vacuum of space or likewise a spacecraft that...

 proposal, called the X-20
X-20 Dyna-Soar
The X-20 Dyna-Soar was a United States Air Force program to develop a spaceplane that could be used for a variety of military missions, including reconnaissance, bombing, space rescue, satellite maintenance, and sabotage of enemy satellites...

, which was not constructed, as well as variety of aerospace plane concepts and studies. Neil Armstrong
Neil Armstrong
Neil Alden Armstrong is an American former astronaut, test pilot, aerospace engineer, university professor, United States Naval Aviator, and the first person to set foot upon the Moon....

 was selected to pilot both the X-15 and the X-20. Though the X-20 was not built, another spaceplane similar to the X-20 was built several years later and delivered to NASA in January 1966 called the HL-10
Northrop HL-10
The Northrop HL-10 was one of five heavyweight lifting body designs flown at NASA's Flight Research Center , Edwards, California, from July 1966 to November 1975 to study and validate the concept of safely maneuvering and landing a low lift-over-drag vehicle designed for reentry from space...

 ("HL" indicated "horizontal landing").

In the mid-1960s, the US Air Force conducted a series of classified studies on next-generation space transportation systems and concluded that semi-reusable designs were the cheapest choice. It proposed a development program with an immediate start on a "Class I" vehicle with expendable boosters, followed by slower development of a "Class II" semi-reusable design and perhaps a "Class III" fully reusable design later. In 1967, George Mueller
George Mueller (NASA)
George Mueller was Associate Administrator of the NASA Office of Manned Space Flight from September 1963 until December 1969...

 held a one-day symposium at NASA headquarters to study the options. Eighty people attended and presented a wide variety of designs, including earlier Air Force designs as the Dyna-Soar (X-20).

In 1968, NASA officially began work on what was then known as the Integrated Launch and Re-entry Vehicle (ILRV). At the same time, NASA held a separate Space Shuttle Main Engine
Space Shuttle main engine
The RS-25, otherwise known as the Space Shuttle Main Engine , is a reusable liquid-fuel rocket engine built by Pratt & Whitney Rocketdyne for the Space Shuttle, running on liquid hydrogen and oxygen. Each Space Shuttle was propelled by three SSMEs mated to one powerhead...

 (SSME) competition. NASA offices in Houston and Huntsville
Huntsville, Alabama
Huntsville is a city located primarily in Madison County in the central part of the far northern region of the U.S. state of Alabama. Huntsville is the county seat of Madison County. The city extends west into neighboring Limestone County. Huntsville's population was 180,105 as of the 2010 Census....

 jointly issued a Request for Proposal
Request for Proposal
A request for proposal is issued at an early stage in a procurement process, where an invitation is presented for suppliers, often through a bidding process, to submit a proposal on a specific commodity or service. The RFP process brings structure to the procurement decision and is meant to...

 (RFP) for ILRV studies to design a spacecraft that could deliver a payload to orbit but also re-enter the atmosphere and fly back to Earth. For example, one of the responses was for a two-stage design, featuring a large booster and a small orbiter, called the DC-3
North American DC-3
The DC-3 was a proposed space shuttle designed by Maxime Faget at the Manned Spacecraft Center in Houston. The design was nominally developed by North American Aviation , although it was a purely NASA-internal design....

, one of several Phase A shuttle designs. After the aforementioned "Phase A" studies, B, C, and D phases progressively evaluated in-depth designs up to 1972. In the final design, the bottom stage was recoverable solid rocket boosters, and the top stage used an expendable external tank.

In 1969, President Richard Nixon
Richard Nixon
Richard Milhous Nixon was the 37th President of the United States, serving from 1969 to 1974. The only president to resign the office, Nixon had previously served as a US representative and senator from California and as the 36th Vice President of the United States from 1953 to 1961 under...

 decided to support proceeding with Space Shuttle development. A series of development programs and analysis refined the basic design, prior to full development and testing. In August 1973, the X-24B proved that an unpowered spaceplane could re-enter Earth's atmosphere for a horizontal landing.

Across the Atlantic, European ministers met in Belgium in 1973 to authorize Western Europe's manned orbital project and its main contribution to Space Shuttlethe Spacelab program. Spacelab would provide a multi-disciplinary orbital space laboratory and additional space equipment for the Shuttle.

Description


The Space Shuttle was the first operational orbital spacecraft designed for reuse
Reusable launch system
A reusable launch system is a launch system which is capable of launching a launch vehicle into space more than once. This contrasts with expendable launch systems, where each launch vehicle is launched once and then discarded.No true orbital reusable launch system is currently in use. The...

. It carried different payloads to low Earth orbit
Low Earth orbit
A low Earth orbit is generally defined as an orbit within the locus extending from the Earth’s surface up to an altitude of 2,000 km...

, provided crew rotation for the International Space Station
International Space Station
The International Space Station is a habitable, artificial satellite in low Earth orbit. The ISS follows the Salyut, Almaz, Cosmos, Skylab, and Mir space stations, as the 11th space station launched, not including the Genesis I and II prototypes...

 (ISS), and performed servicing missions. The orbiter could also recover satellites and other payloads from orbit and return them to Earth. Each Shuttle was designed for a projected lifespan of 100 launches or ten years of operational life, although this was later extended. The person in charge of designing the STS was Maxime Faget
Maxime Faget
Maxime "Max" A. Faget was the designer of the Mercury capsule, and contributed to the later Gemini and Apollo spacecraft as well as the Space Shuttle.- Life :...

, who had also overseen the Mercury
Project Mercury
In January 1960 NASA awarded Western Electric Company a contract for the Mercury tracking network. The value of the contract was over $33 million. Also in January, McDonnell delivered the first production-type Mercury spacecraft, less than a year after award of the formal contract. On February 12,...

, Gemini
Project Gemini
Project Gemini was the second human spaceflight program of NASA, the civilian space agency of the United States government. Project Gemini was conducted between projects Mercury and Apollo, with ten manned flights occurring in 1965 and 1966....

, 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 commercial and military satellites, and have the cross-range recovery range to meet the requirement for classified USAF missions for a once-around abort from a launch to a polar orbit
Polar orbit
A polar orbit is an orbit in which a satellite passes above or nearly above both poles of the body being orbited on each revolution. It therefore has an inclination of 90 degrees to the equator...

. Factors involved in opting for 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
Space exploration
Space exploration is the use of space technology to explore outer space. Physical exploration of space is conducted both by human spaceflights and by robotic spacecraft....

 by developing a spacecraft with reusable components.

Each Space Shuttle is a reusable launch system
Reusable launch system
A reusable launch system is a launch system which is capable of launching a launch vehicle into space more than once. This contrasts with expendable launch systems, where each launch vehicle is launched once and then discarded.No true orbital reusable launch system is currently in use. The...

 that is composed of three main assemblies: the reusable Orbiter Vehicle
Space Shuttle Orbiter
The Space Shuttle orbiter was the orbital spacecraft of the Space Shuttle program operated by NASA, the space agency of the United States. The orbiter was a reusable winged "space-plane", a mixture of rockets, spacecraft, and aircraft...

 (OV), the expendable external tank
Space Shuttle external tank
A Space Shuttle External Tank is the component of the Space Shuttle launch vehicle that contains the liquid hydrogen fuel and liquid oxygen oxidizer. During lift-off and ascent it supplies the fuel and oxidizer under pressure to the three Space Shuttle Main Engines in the orbiter...

 (ET), and the two reusable solid rocket boosters
Space Shuttle Solid Rocket Booster
The Space Shuttle Solid Rocket Boosters were the pair of large solid rockets used by the United States' NASA Space Shuttle during the first two minutes of powered flight. Together they provided about 83% of liftoff thrust for the Space Shuttle. They were located on either side of the rusty or...

 (SRBs). Only the orbiter entered orbit shortly after the tank and boosters are jettisoned. The vehicle was launched vertically like a conventional rocket, and the orbiter glided to a horizontal landing like an airplane, after which it was refurbished for reuse. The SRBs parachuted to splashdown in the ocean where they were towed back to shore and refurbished for later shuttle missions.

Five space-worthy orbiters were built: Columbia
Space Shuttle Columbia
Space Shuttle Columbia was the first spaceworthy Space Shuttle in NASA's orbital fleet. First launched on the STS-1 mission, the first of the Space Shuttle program, it completed 27 missions before being destroyed during re-entry on February 1, 2003 near the end of its 28th, STS-107. All seven crew...

 (OV-102), Challenger
Space Shuttle Challenger
Space Shuttle Challenger was NASA's second Space Shuttle orbiter to be put into service, Columbia having been the first. The shuttle was built by Rockwell International's Space Transportation Systems Division in Downey, California...

 (OV-099), Discovery
Space Shuttle Discovery
Space Shuttle Discovery is one of the retired orbiters of the Space Shuttle program of NASA, the space agency of the United States, and was operational from its maiden flight, STS-41-D on August 30, 1984, until its final landing during STS-133 on March 9, 2011...

 (OV-103), Atlantis
Space Shuttle Atlantis
The Space Shuttle Atlantis is a retired Space Shuttle orbiter in the Space Shuttle fleet belonging to the National Aeronautics and Space Administration , the spaceflight and space exploration agency of the United States...

 (OV-104), and Endeavour
Space Shuttle Endeavour
Space Shuttle Endeavour is one of the retired orbiters of the Space Shuttle program of NASA, the space agency of the United States. Endeavour was the fifth and final spaceworthy NASA space shuttle to be built, constructed as a replacement for Challenger...

 (OV-105). A mock-up, Inspiration (OV-100), currently stands at the entrance to the Astronaut Hall of Fame. An additional craft, Enterprise
Space Shuttle Enterprise
The Space Shuttle Enterprise was the first Space Shuttle orbiter. It was built for NASA as part of the Space Shuttle program to perform test flights in the atmosphere. It was constructed without engines or a functional heat shield, and was therefore not capable of spaceflight...

 (OV-101), was not built for orbital space flight, and was used only for testing gliding and landing. Enterprise was originally intended to be made fully space-worthy after use for the approach and landing test (ALT) program, but it was found more economical to upgrade the structural test article STA-099 into orbiter Challenger (OV-099). Challenger disintegrated
Space Shuttle Challenger disaster
The Space Shuttle Challenger disaster occurred on January 28, 1986, when Space Shuttle Challenger broke apart 73 seconds into its flight, leading to the deaths of its seven crew members. The spacecraft disintegrated over the Atlantic Ocean, off the coast of central Florida at 11:38 am EST...

 73 seconds after launch in 1986, and Endeavour was built as a replacement for Challenger from structural spare components. Columbia broke apart
Space Shuttle Columbia disaster
The Space Shuttle Columbia disaster occurred on February 1, 2003, when shortly before it was scheduled to conclude its 28th mission, STS-107, the Space Shuttle Columbia disintegrated over Texas and Louisiana during re-entry into the Earth's atmosphere, resulting in the death of all seven crew members...

 during re-entry in 2003. Building Space Shuttle Endeavour cost about US$1.7 billion. One Space Shuttle launch costs around $450 million.

Roger A. Pielke, Jr. has estimated that the Space Shuttle program
Space Shuttle program
NASA's Space Shuttle program, officially called Space Transportation System , was the United States government's manned launch vehicle program from 1981 to 2011...

 has cost about US$170 billion (2008 dollars) through early 2008. This works out to an average cost per flight of about US$1.5 billion. However, two missions were paid for by Germany, Spacelab D1
STS-61-A
STS-61-A was the 22nd mission of NASA's Space Shuttle program. It was a scientific Spacelab mission, funded and directed by West Germany – hence the non-NASA designation of D-1 . STS-61-A was the last successful mission of the Space Shuttle Challenger, which was destroyed during STS-51-L in 1986...

 and D2
STS-55
-Backup crew:-Mission parameters:*Mass:**Orbiter landing with payload: **Payload: *Perigee: *Apogee: *Inclination: 28.5°*Period: 90.7 min-Mission highlights:...

 (D for Deutschland) with a payload control center in Oberpfaffenhofen
Oberpfaffenhofen
Oberpfaffenhofen is a village which is part of the municipality of Weßling in the district of Starnberg, Bavaria, Germany. It is 20 kilometers from the city center of Munich....

, Germany. D1 was the first time that control of a manned STS mission payload was not in U.S. hands.

At times, the orbiter itself was referred to as the Space Shuttle. Technically, this was a slight misnomer, as the actual "Space Transportation System" (Space Shuttle) was the combination of the orbiter, the external tank, and the two solid rocket boosters. Combined, these were referred to as the "stack"; the components were assembled in the Vehicle Assembly Building
Vehicle Assembly Building
The Vehicle Assembly Building, or VAB, at NASA's Kennedy Space Center was used to assemble and house American manned launch vehicles from 1968-2011. It is the fourth largest building in the world by volume...

, originally built to assemble the Apollo Saturn V rocket.

Responsibility for the shuttle components was spread among multiple NASA field centers. The Kennedy Space Center was responsible for launch, landing and turnaround operations for equatorial orbits (the only orbit profile actually used in the program), the US Air Force at the Vandenberg Air Force Base
Vandenberg Air Force Base
Vandenberg Air Force Base is a United States Air Force Base, located approximately northwest of Lompoc, California. It is under the jurisdiction of the 30th Space Wing, Air Force Space Command ....

 was responsible for launch, landing and turnaround operations for polar orbits (though this was never used), the Johnson Space Center served as the central point for all shuttle operations, the Marshall Space Flight Center
Marshall Space Flight Center
The George C. Marshall Space Flight Center is the U.S. government's civilian rocketry and spacecraft propulsion research center. The largest center of NASA, MSFC's first mission was developing the Saturn launch vehicles for the Apollo moon program...

 was responsible for the main engines, external tank, and solid rocket boosters, the John C. Stennis Space Center
John C. Stennis Space Center
The John C. Stennis Space Center , located in Hancock County, Mississippi, at the Mississippi-Louisiana border, is NASA's largest rocket engine test facility.- History :...

 handled main engine testing, and the Goddard Space Flight Center
Goddard Space Flight Center
The Goddard Space Flight Center is a major NASA space research laboratory established on May 1, 1959 as NASA's first space flight center. GSFC employs approximately 10,000 civil servants and contractors, and is located approximately northeast of Washington, D.C. in Greenbelt, Maryland, USA. GSFC,...

 managed the global tracking network.

Orbiter vehicle



The orbiter resembles a conventional 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 elevon
Elevon
Elevons are aircraft control surfaces that combine the functions of the elevator and the aileron , hence the name. They are frequently used on tailless aircraft such as flying wings. An elevon that is not part of the main wing, but instead is a separate tail surface, is a stabilator...

s, mounted at the trailing edge of the wings, and the rudder
Rudder
A rudder is a device used to steer a ship, boat, submarine, hovercraft, aircraft or other conveyance that moves through a medium . On an aircraft the rudder is used primarily to counter adverse yaw and p-factor and is not the primary control used to turn the airplane...

/speed brake, attached at the trailing edge of the stabilizer, with the body flap, controlled the orbiter during descent and landing.

The orbiter's payload bay measures 15 by, comprising most of the fuselage
Fuselage
The fuselage is an aircraft's main body section that holds crew and passengers or cargo. In single-engine aircraft it will usually contain an engine, although in some amphibious aircraft the single engine is mounted on a pylon attached to the fuselage which in turn is used as a floating hull...

. Information declassified in 2011 showed that the payload bay was designed specifically to accommodate the KH-9 HEXAGON spy satellite operated by the National Reconnaissance Office
National Reconnaissance Office
The National Reconnaissance Office , located in Chantilly, Virginia, is one of the 16 U.S. intelligence agencies. It designs, builds, and operates the spy satellites of the United States government.-Mission:...

. Two mostly symmetrical lengthwise payload bay doors hinged on either side of the bay comprise its entire top. Payloads are generally loaded horizontally into the bay while the orbiter is oriented vertically on the launch pad and unloaded vertically in the near-weightless orbital environment by the orbiter's robotic remote manipulator arm (under astronaut control), EVA astronauts, or under the payloads' own power (as for satellites attached to a rocket "upper stage" for deployment.)

Three Space Shuttle Main Engines (SSMEs) are mounted on the orbiter's aft fuselage in a triangular pattern. The engine nozzles 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 to steer the shuttle. The orbiter structure is made primarily from aluminum
Aluminium
Aluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....

 alloy
Alloy
An alloy is a mixture or metallic solid solution composed of two or more elements. Complete solid solution alloys give single solid phase microstructure, while partial solutions give two or more phases that may or may not be homogeneous in distribution, depending on thermal history...

, although the engine structure is made primarily from titanium
Titanium
Titanium is a chemical element with the symbol Ti and atomic number 22. It has a low density and is a strong, lustrous, corrosion-resistant transition metal with a silver color....

 alloy.

The space-capable orbiters built were OV-102 Columbia
Space Shuttle Columbia
Space Shuttle Columbia was the first spaceworthy Space Shuttle in NASA's orbital fleet. First launched on the STS-1 mission, the first of the Space Shuttle program, it completed 27 missions before being destroyed during re-entry on February 1, 2003 near the end of its 28th, STS-107. All seven crew...

, OV-099 Challenger
Space Shuttle Challenger
Space Shuttle Challenger was NASA's second Space Shuttle orbiter to be put into service, Columbia having been the first. The shuttle was built by Rockwell International's Space Transportation Systems Division in Downey, California...

, OV-103 Discovery
Space Shuttle Discovery
Space Shuttle Discovery is one of the retired orbiters of the Space Shuttle program of NASA, the space agency of the United States, and was operational from its maiden flight, STS-41-D on August 30, 1984, until its final landing during STS-133 on March 9, 2011...

, OV-104 Atlantis
Space Shuttle Atlantis
The Space Shuttle Atlantis is a retired Space Shuttle orbiter in the Space Shuttle fleet belonging to the National Aeronautics and Space Administration , the spaceflight and space exploration agency of the United States...

, and OV-105 Endeavour
Space Shuttle Endeavour
Space Shuttle Endeavour is one of the retired orbiters of the Space Shuttle program of NASA, the space agency of the United States. Endeavour was the fifth and final spaceworthy NASA space shuttle to be built, constructed as a replacement for Challenger...

.


External tank


The main function of the Space Shuttle external tank was to supply the liquid oxygen and hydrogen fuel to the main engines. It was also the backbone of the launch vehicle, providing attachment points for the two Solid Rocket Boosters and the Orbiter. The external tank was the only part of the shuttle system that was not reused. Although the external tanks were always discarded, it was possible to take them into orbit and re-use them (such as for incorporation into a space station).

Solid rocket boosters


Two solid rocket boosters (SRBs) each provided 12.5 million newtons (2.8 million lbf) of thrust at liftoff, which was 83% of the total thrust needed for liftoff. The SRBs were jettisoned two minutes after launch at a height of about 150000 feet (45.7 km), and then deployed parachutes and landed in the ocean to be recovered. The SRB cases were made of steel about ½ inch (13 mm) thick. The Solid Rocket Boosters were re-used many times; the casing used in Ares I
Ares I
Ares I was the crew launch vehicle that was being developed by NASA as part of the Constellation Program. The name "Ares" refers to the Greek deity Ares, who is identified with the Roman god Mars...

 engine testing in 2009 consisted of motor cases that had been flown, collectively, on 48 shuttle missions, including STS-1
STS-1
STS-1 was the first orbital flight of NASA's Space Shuttle program. Space Shuttle Columbia launched on 12 April 1981, and returned to Earth on 14 April, having orbited the Earth 37 times during the 54.5-hour mission. It was the first American manned space flight since the Apollo-Soyuz Test Project...

.

Orbiter add-ons


The orbiter could be used in conjunction with a variety of add-ons depending on the mission. This has included orbital laboratories (Spacelab
Spacelab
Spacelab was a reusable laboratory used on certain spaceflights flown by the Space Shuttle. The laboratory consisted of multiple components, including a pressurized module, an unpressurized carrier and other related hardware housed in the Shuttle's cargo bay...

, Spacehab
SPACEHAB
Astrotech Corporation , formerly Spacehab Inc., is an aerospace company headquartered in Austin, Texas which provides commercial space products and services to NASA, the U.S. Department of Defense, international space agencies, and global commercial customers...

), boosters for launching payloads farther into space (Inertial Upper Stage
Inertial Upper Stage
The Inertial Upper Stage , originally known as the Interim Upper Stage, is a two-stage solid-fueled booster rocket developed by the U.S...

, Payload Assist Module
Payload Assist Module
frame|PAM-D with the [[Phoenix |Phoenix]] spacecraft. The [[Star 48|Star 48-B]] engine is shown being spun, fired, [[Yo-yo de-spin|yo-yo de-spun]] and jettisoned.thumb|SBS-3 satellite with PAM-D stage inside the space shuttle...

), and other functions, such as provided by Extended Duration Orbiter
Extended Duration Orbiter
The Extended Duration Orbiter program was a project by NASA to prepare for long-term microgravity research aboard Space Station Freedom, which later evolved into the International Space Station. Scientists and NASA needed practical experience in managing progressively longer times for their...

, Multi-Purpose Logistics Module
Multi-Purpose Logistics Module
A Multi-Purpose Logistics Module is a large pressurized container used on Space Shuttle missions to transfer cargo to and from the International Space Station . An MPLM was carried in the cargo bay of a Shuttle and berthed to the Unity or Harmony modules on the ISS. From there, supplies were...

s, or Canadarm (RMS). An upper-stage called Transfer Orbit Stage
Transfer orbit stage
The Transfer Orbit Stage was an upper stage developed by Martin Marietta for Orbital Sciences Corporation during the late 1980s and early 1990s. The TOS was designed to be a lower-cost alternative to Inertial Upper Stage and Centaur upper stages...

 (Orbital Science Corp. TOS-21) was also used once. Other types of systems and racks were part of the modular Spacelab system pallets, igloo, IPS, etc., which also supported special missions such as SRTM
Shuttle Radar Topography Mission
The Shuttle Radar Topography Mission is an international research effort that obtained digital elevation models on a near-global scale from 56° S to 60° N, to generate the most complete high-resolution digital topographic database of Earth prior to the release of the ASTER GDEM in 2009...

.


Spacelab


A major component of the Space Shuttle Program was Spacelab, primarily contributed by a consortium of European countries, and operated in conjunction with the United States and international partners. Supported by a modular system of pressurized modules, pallets, and systems, Spacelab missions executed on multidisciplinary science, orbital logistics, international cooperation. Over 29 missions flew on subjects ranging from astronomy, microgravity, radar, and life sciences, to name a few. Spacelab hardware also supported missions such as Hubble (HST) servicing and space station resupply. STS-2 and STS-3 provided testing, and the first full mission was Spacelab-1 (STS-9
STS-9
STS-9 was a NASA Space Shuttle mission which carried the first Spacelab module into orbit to conduct space-based scientific experiments. It was the sixth mission of the Space Shuttle Columbia, and was Columbia's last flight until STS-61-C in January 1986...

) launched on November 28, 1983.

Spacelab formally began in 1973, after a meeting in Brussels, Belgium, by European heads of state. Within the decade, Spacelab would go into orbit and provide not only Europe, but also the United States, with an orbital workshop and hardware system. International cooperation, science, and exploration were realized on Spacelab.

Flight systems


The shuttle was one of the earliest craft to use a computerized fly-by-wire
Fly-by-wire
Fly-by-wire is a system that replaces the conventional manual flight controls of an aircraft with an electronic interface. The movements of flight controls are converted to electronic signals transmitted by wires , and flight control computers determine how to move the actuators at each control...

 digital flight control system. This means no mechanical or hydraulic linkages connected the pilot's control stick to the control surfaces or reaction control system
Reaction control system
A reaction control system is a subsystem of a spacecraft whose purpose is attitude control and steering by the use of thrusters. An RCS system is capable of providing small amounts of thrust in any desired direction or combination of directions. An RCS is also capable of providing torque to allow...

 thrusters.

A concern with digital fly-by-wire systems is reliability. Considerable research went into the shuttle computer system. The shuttle used five identical redundant IBM 32-bit general purpose computers (GPCs), model AP-101
IBM AP-101
The IBM AP-101 is an avionics computer, used most notably in the U.S. Space Shuttle, but since also in the B-52 and B-1B bombers and the F-15 fighter, among others. When it was designed, it was a high-performance pipelined processor with core memory...

, constituting a type of embedded system
Embedded system
An embedded system is a computer system designed for specific control functions within a larger system. often with real-time computing constraints. It is embedded as part of a complete device often including hardware and mechanical parts. By contrast, a general-purpose computer, such as a personal...

. Four computers ran specialized software called the Primary Avionics Software System (PASS). A fifth backup computer ran separate software called the Backup Flight System (BFS). Collectively they were called the Data Processing System (DPS).

The design goal of the shuttle's DPS was fail-operational/fail-safe reliability. After a single failure, the shuttle could still continue the mission. After two failures, it could still land safely.

The four general-purpose computers operated essentially in lockstep, checking each other. If one computer failed, the three functioning computers "voted" it out of the system. This isolated it from vehicle control. If a second computer of the three remaining failed, the two functioning computers voted it out. In the unlikely case of two out of four computers simultaneously failed (a two-two split), one group was to be picked at random.

The Backup Flight System (BFS) was separately developed software running on the fifth computer, used only if the entire four-computer primary system failed. The BFS was created because although the four primary computers were hardware redundant, they all ran the same software, so a generic software problem could crash all of them. Embedded system
Embedded system
An embedded system is a computer system designed for specific control functions within a larger system. often with real-time computing constraints. It is embedded as part of a complete device often including hardware and mechanical parts. By contrast, a general-purpose computer, such as a personal...

 avionic
Avionics
Avionics are electronic systems used on aircraft, artificial satellites and spacecraft.Avionic systems include communications, navigation, the display and management of multiple systems and the hundreds of systems that are fitted to aircraft to meet individual roles...

 software was developed under totally different conditions from public commercial software: the number of code lines was tiny compared to a public commercial software, changes were only made infrequently and with extensive testing, and many programming and test personnel worked on the small amount of computer code. However, in theory it could have still failed, and the BFS existed for that contingency. While the BFS could run in parallel with PASS, the BFS never engaged to take over control from PASS during any shuttle mission.

The software for the shuttle computers was written in a high-level language called HAL/S
HAL/S
HAL/S is a real-time aerospace programming language, best known for its use in the Space Shuttle program. It was designed by Intermetrics in the 1970s for NASA. HAL/S is written in XPL, a dialect of PL/I....

, somewhat similar to PL/I
PL/I
PL/I is a procedural, imperative computer programming language designed for scientific, engineering, business and systems programming applications...

. It is specifically designed for a real time
Real-time computing
In computer science, real-time computing , or reactive computing, is the study of hardware and software systems that are subject to a "real-time constraint"— e.g. operational deadlines from event to system response. Real-time programs must guarantee response within strict time constraints...

 embedded system
Embedded system
An embedded system is a computer system designed for specific control functions within a larger system. often with real-time computing constraints. It is embedded as part of a complete device often including hardware and mechanical parts. By contrast, a general-purpose computer, such as a personal...

 environment.

The IBM AP-101 computers originally had about 424 kilobytes of magnetic core memory
Magnetic core memory
Magnetic-core memory was the predominant form of random-access computer memory for 20 years . It uses tiny magnetic toroids , the cores, through which wires are threaded to write and read information. Each core represents one bit of information...

 each. The CPU could process about 400,000 instructions per second. They had no hard disk drive, and load software from magnetic tape cartridges.

In 1990, the original computers were replaced with an upgraded model AP-101S, which had about 2.5 times the memory capacity (about 1 megabyte) and three times the processor speed (about 1.2 million instructions per second). The memory was changed from magnetic core to semiconductor with battery backup.

Early shuttle missions, starting in November 1983, took along the GRiD Compass
GRiD Compass
The Grid Compass was one of the first laptop computers when the initial model was introduced in April 1982 ....

, arguably one of the first laptop computers. The GRiD was given the name SPOC, for Shuttle Portable Onboard Computer. Use on the Shuttle required both hardware and software modifications which were incorporated into later versions of the commercial product. It was used to monitor and display the Shuttle's ground position, path of the next two orbits, show where the shuttle had line of sight communications with ground stations, and determine points for location-specific observations of the Earth. The Compass sold poorly, as it cost at least US$8000, but it offered unmatched performance for its weight and size. NASA was one of its main customers.

Orbiter markings and insignia


The typeface
Typeface
In typography, a typeface is the artistic representation or interpretation of characters; it is the way the type looks. Each type is designed and there are thousands of different typefaces in existence, with new ones being developed constantly....

 used on the Space Shuttle Orbiter is Helvetica
Helvetica
Helvetica is a widely used sans-serif typeface developed in 1957 by Swiss typeface designer Max Miedinger with Eduard Hoffmann.-Visual distinctive characteristics:Characteristics of this typeface are:lower case:square dot over the letter i....

. On the side of the shuttle between the cockpit windows and the cargo bay doors is the name of the orbiter. Underneath the rear of the cargo bay doors have been various NASA insignia
NASA logo
The National Aeronautics and Space Administration logo has three main official designs, although the one with stylized red curved text has been retired from official use since 1992...

, the text "United States" and a flag of the United States
Flag of the United States
The national flag of the United States of America consists of thirteen equal horizontal stripes of red alternating with white, with a blue rectangle in the canton bearing fifty small, white, five-pointed stars arranged in nine offset horizontal rows of six stars alternating with rows...

.

Columbia, being the first orbiter built, had a flag of the United States
Flag of the United States
The national flag of the United States of America consists of thirteen equal horizontal stripes of red alternating with white, with a blue rectangle in the canton bearing fifty small, white, five-pointed stars arranged in nine offset horizontal rows of six stars alternating with rows...

 on the left wing and a "USA" in bold on the left wing and the word "Columbia" on the Payload Bay Doors from STS-1
STS-1
STS-1 was the first orbital flight of NASA's Space Shuttle program. Space Shuttle Columbia launched on 12 April 1981, and returned to Earth on 14 April, having orbited the Earth 37 times during the 54.5-hour mission. It was the first American manned space flight since the Apollo-Soyuz Test Project...

 to STS-9
STS-9
STS-9 was a NASA Space Shuttle mission which carried the first Spacelab module into orbit to conduct space-based scientific experiments. It was the sixth mission of the Space Shuttle Columbia, and was Columbia's last flight until STS-61-C in January 1986...

. Afterwards it was moved to the usual position as on the other orbiters. Challenger wore the letters "USA" and the flag on the left wing, with the NASA worm lettering and the word "Challenger" below it on the right wing. Challenger also had a different hatch tile pattern. As a result of the early loss of Challenger, it is the only orbiter never to wear the "meatball" logo on its left wing. The subsequent orbiters benefited from technological advances in tile positioning and were largely similar.

Upgrades



The Space Shuttle was initially developed in the 1970s, but received many upgrades and modifications afterward for improvements ranging from performance and reliability to safety. Internally, the shuttle remained largely similar to the original design, with the exception of the improved avionics computers. In addition to the computer upgrades, the original analog primary flight instruments were replaced with modern full-color, flat-panel display screens, called a glass cockpit
Glass cockpit
A glass cockpit is an aircraft cockpit that features electronic instrument displays, typically large LCD screens, as opposed to the traditional style of analog dials and gauges...

, which is similar to those of contemporary airliners. With the coming of the ISS, the orbiter's internal airlocks were replaced with external docking systems to allow for a greater amount of cargo to be stored on the shuttle's mid-deck during station resupply missions.

The Space Shuttle Main Engines (SSMEs) had several improvements to enhance reliability and power. This explains phrases such as "Main engines throttling up to 104 percent." This did not mean the engines were being run over a safe limit. The 100 percent figure was the original specified power level. During the lengthy development program, Rocketdyne
Rocketdyne
Rocketdyne was a Rocket engine design and production company headquartered in Canoga Park, California, United States. The company was related to North American Aviation for most of its history. NAA merged with Rockwell International, which was then bought by Boeing in December, 1996...

 determined the engine was capable of safe reliable operation at 104 percent of the originally specified thrust. NASA could have rescaled the output number, saying in essence 104 percent is now 100 percent. To clarify this would have required revising much previous documentation and software, so the 104 percent number was retained. SSME upgrades were denoted as "block numbers", such as block I, block II, and block IIA. The upgrades improved engine reliability, maintainability and performance. The 109% thrust level was finally reached in flight hardware with the Block II engines in 2001. The normal maximum throttle was 104 percent, with 106 percent or 109 percent used for mission aborts.

For the first two missions, STS-1
STS-1
STS-1 was the first orbital flight of NASA's Space Shuttle program. Space Shuttle Columbia launched on 12 April 1981, and returned to Earth on 14 April, having orbited the Earth 37 times during the 54.5-hour mission. It was the first American manned space flight since the Apollo-Soyuz Test Project...

 and STS-2
STS-2
STS-2 was a Space Shuttle mission conducted by NASA, using the Space Shuttle Columbia. The mission launched on 12 November 1981. It was the second shuttle mission overall, and was also the second mission for Columbia...

, the external tank was painted white to protect the insulation that covers much of the tank, but improvements and testing showed that it was not required. The weight saved by not painting the tank resulted in an increase in payload capability to orbit. Additional weight was saved by removing some of the internal "stringers" in the hydrogen tank that proved unnecessary. The resulting "light-weight external tank" has been used on the vast majority of shuttle missions. STS-91
STS-91
STS-91 was the final Space Shuttle mission to the Mir space station. It was flown by Space Shuttle Discovery, and launched from Kennedy Space Center, Florida, on 2 June 1998.-Crew:-Mission parameters:*Mass:...

 saw the first flight of the "super light-weight external tank". This version of the tank is made of the 2195 aluminum-lithium alloy. It weighs 3.4 metric tons (7,500 lb) less than the last run of lightweight tanks. As the shuttle was not flown unmanned, each of these improvements was "tested" on operational flights.

The SRBs (Solid Rocket Boosters) underwent improvements as well. Design engineers added a third O-ring
O-ring
An O-ring, also known as a packing, or a toric joint, is a mechanical gasket in the shape of a torus; it is a loop of elastomer with a disc-shaped cross-section, designed to be seated in a groove and compressed during assembly between two or more parts, creating a seal at the interface.The O-ring...

 seal to the joints between the segments after the 1986 Space Shuttle Challenger disaster
Space Shuttle Challenger disaster
The Space Shuttle Challenger disaster occurred on January 28, 1986, when Space Shuttle Challenger broke apart 73 seconds into its flight, leading to the deaths of its seven crew members. The spacecraft disintegrated over the Atlantic Ocean, off the coast of central Florida at 11:38 am EST...

.

Several other SRB improvements were planned to improve performance and safety, but never came to be. These culminated in the considerably simpler, lower cost, probably safer and better-performing Advanced Solid Rocket Booster. These rockets entered production in the early to mid-1990s to support the Space Station, but were later canceled to save money after the expenditure of $2.2 billion. The loss of the ASRB program resulted in the development of the Super LightWeight external Tank (SLWT), which provided some of the increased payload capability, while not providing any of the safety improvements. In addition, the Air Force developed their own much lighter single-piece SRB design using a filament-wound system, but this too was canceled.

STS-70
STS-70
STS-70 was the 21st flight of the Space Shuttle Discovery, and the last of 7 shuttle missions to carry a Tracking and Data Relay Satellite . This was the first shuttle mission controlled from the new Mission Control Center room at the Johnson Space Center in Houston...

 was delayed in 1995, when woodpecker
Woodpecker
Woodpeckers are near passerine birds of the order Piciformes. They are one subfamily in the family Picidae, which also includes the piculets and wrynecks. They are found worldwide and include about 180 species....

s bored holes in the foam insulation of Discoverys external tank. Since then, NASA has installed commercial plastic owl decoys and inflatable owl balloons which had to be removed prior to launch. The delicate nature of the foam insulation had been the cause of damage to the Thermal Protection System
Space Shuttle thermal protection system
The Space Shuttle thermal protection system is the barrier that protects the Space Shuttle Orbiter during the searing heat of atmospheric reentry...

, the tile heat shield and heat wrap of the orbiter. NASA remained confident that this damage, while it was the primary cause of the Space Shuttle Columbia disaster
Space Shuttle Columbia disaster
The Space Shuttle Columbia disaster occurred on February 1, 2003, when shortly before it was scheduled to conclude its 28th mission, STS-107, the Space Shuttle Columbia disintegrated over Texas and Louisiana during re-entry into the Earth's atmosphere, resulting in the death of all seven crew members...

 on February 1, 2003, would not jeopardize the completion the International Space Station (ISS) in the projected time allotted.

A cargo-only, unmanned variant of the shuttle was variously proposed and rejected since the 1980s. It was called the Shuttle-C
Shuttle-C
The Shuttle-C was a NASA proposal to turn the Space Shuttle launch stack into a dedicated unmanned cargo launcher. This would use the Space Shuttle external tank and Space Shuttle Solid Rocket Boosters , combined with a cargo module that would attach to Shuttle hardpoints and include the Space...

, and would have traded re-usability for cargo capability, with large potential savings from reusing technology developed for the Space Shuttle. Another proposal was to convert the payload bay into a passenger area, with proposals ranging from 30 to 74 seats, three days in orbit, and 1.5 million USD a seat.

On the first four shuttle missions, astronauts wore modified US Air Force high-altitude full-pressure suits, which included a full-pressure helmet during ascent and descent. From the fifth flight, STS-5
STS-5
STS-5 was a NASA Space Shuttle mission, the fifth shuttle mission overall and the fifth flight of the Space Shuttle Columbia. It was the first shuttle mission to deploy communications satellites into orbit...

, until the loss of Challenger
Space Shuttle Challenger disaster
The Space Shuttle Challenger disaster occurred on January 28, 1986, when Space Shuttle Challenger broke apart 73 seconds into its flight, leading to the deaths of its seven crew members. The spacecraft disintegrated over the Atlantic Ocean, off the coast of central Florida at 11:38 am EST...

, one-piece light blue nomex
Nomex
Nomex is a registered trademark for flame resistant meta-aramid material developed in the early 1960s by DuPont and first marketed in 1967.- Properties:...

 flight suits and partial-pressure helmets were worn. A less-bulky, partial-pressure version of the high-altitude pressure suits with a helmet was reinstated when shuttle flights resumed in 1988. The Launch-Entry Suit ended its service life in late 1995, and was replaced by the full-pressure Advanced Crew Escape Suit
Advanced Crew Escape Suit
The Advanced Crew Escape Suit or "pumpkin suit", was a full pressure suit that began to be worn by Space Shuttle crews after STS-65, for the ascent and entry portions of flight. The suit is a direct descendant of the U.S...

 (ACES), which resembled the Gemini space suit
Gemini Space suit
The Gemini space suit is a space suit worn by astronauts for launch, in-flight activities and landing. It was designed by NASA based on the X-15 high-altitude pressure suit...

 in design, but retained the orange color of the Launch-Entry Suit.

To extend the duration that orbiters could stay docked at the ISS, the Station-to-Shuttle Power Transfer System (SSPTS) was installed. The SSPTS allowed these orbiters to use power provided by the ISS to preserve their consumables. The SSPTS was first used successfully on STS-118
STS-118
- Crew notes :Astronaut Clayton Anderson originally was slated to be launched to the ISS on this mission, but was moved to STS-117. His replacement was Alvin Drew....

.

Technical data



Orbiter specifications (for Endeavour, OV-105)
  • Length: 122.17 ft (37.2 m)
  • Wingspan: 78.06 ft (23.8 m)
  • Height: 56.58 ft (17.2 m)
  • Empty weight: 172000 lb (78,017.9 kg)
  • Gross liftoff weight (Orbiter only): 240000 lb (108,862.2 kg)
  • Maximum landing weight: 230000 lb (104,326.2 kg)
  • Payload to Landing (Return Payload): 14,400 kg (32,000 lb)
  • Maximum payload: 55250 lb (25,061 kg)
  • Payload to LEO: 53600 lb (24,312.6 kg)
  • Payload to LEO @ 51.6° inclination (ISS):
  • Payload to GTO: 8390 lb (3,805.6 kg)
  • Payload to Polar Orbit: 28000 lb (12,700.6 kg)
  • (Note launch payloads modified by External Tank (ET) choice (ET, LWT, or SLWT)
  • Payload bay dimensions: 15 by
  • Operational altitude: 100 nmi (185.2 km; 115.1 mi)
  • Speed: 7743 m/s (27,874.8 km/h; 17,320.6 mph)
  • Crossrange: 1085 nmi (2,009.4 km; 1,248.6 mi)
  • First Stage (SSME with external tank)
    • Main engines: Three Rocketdyne Block II SSMEs, each with a sea level thrust
      Thrust
      Thrust is a reaction force described quantitatively by Newton's second and third laws. When a system expels or accelerates mass in one direction the accelerated mass will cause a force of equal magnitude but opposite direction on that system....

       of 393800 lbf (1.8 MN) at 104% power
    • Thrust (at liftoff, sea level, 104% power, all 3 engines): 1181400 lbf (5.3 MN)
    • Specific impulse: 455 s
    • Burn time: 480 s
    • Fuel: Liquid Oxygen/Liquid Hydrogen
  • Second Stage
    • Engines: 2 Orbital Maneuvering Engines
    • Thrust: 53.4 kN (12,004.8 lbf) combined total vacuum thrust
    • Specific impulse: 316 s
    • Burn time: 1250 s
    • Fuel: MMH/N2O4
  • Crew: Varies.
The earliest shuttle flights had the minimum crew of two; many later missions a crew of five. Today, typically seven people fly (commander
Commander
Commander is a naval rank which is also sometimes used as a military title depending on the individual customs of a given military service. Commander is also used as a rank or title in some organizations outside of the armed forces, particularly in police and law enforcement.-Commander as a naval...

, pilot
Aviator
An aviator is a person who flies an aircraft. The first recorded use of the term was in 1887, as a variation of 'aviation', from the Latin avis , coined in 1863 by G. de la Landelle in Aviation Ou Navigation Aérienne...

, several mission specialist
Mission Specialist
A Mission Specialist is a position held by certain NASA astronauts during Space Shuttle missions. A Mission Specialist is assigned to a limited field of the mission, such as for medical experiments or technical quests....

s, and rarely a flight engineer
Flight engineer
Flight engineers work in three types of aircraft: fixed-wing , rotary wing , and space flight .As airplanes became even larger requiring more engines and complex systems to operate, the workload on the two pilots became excessive during certain critical parts of the flight regime, notably takeoffs...

). On two occasions, eight astronauts have flown (STS-61-A
STS-61-A
STS-61-A was the 22nd mission of NASA's Space Shuttle program. It was a scientific Spacelab mission, funded and directed by West Germany – hence the non-NASA designation of D-1 . STS-61-A was the last successful mission of the Space Shuttle Challenger, which was destroyed during STS-51-L in 1986...

, STS-71
STS-71
STS-71 was the third mission of the US/Russian Shuttle-Mir Program, which carried out the first Space Shuttle docking to Mir, a Russian space station. The mission used Space Shuttle Atlantis, which lifted off from launch pad 39A on 27 June 1995 from Kennedy Space Center, Florida...

). Eleven people could be accommodated in an emergency mission (see STS-3xx
STS-3xx
Space Shuttle missions designated STS-3xx were rescue missions which would have been mounted to rescue the crew of a Space Shuttle if their vehicle was damaged and deemed unable to make a successful reentry...

).


External tank specifications (for SLWT)
  • Length: 46.9 m (153.9 ft)
  • Diameter: 8.4 m (27.6 ft)
  • Propellant volume: 2025 m³ (534,948.4 US gal)
  • Empty weight: 26535 kg (58,499.7 lb)
  • Gross liftoff weight (for tank): 756000 kg (1,666,694.7 lb)


Solid Rocket Booster specifications
  • Length: 45.46 m (149.1 ft)
  • Diameter: 3.71 m (12.2 ft)
  • Empty weight (per booster): 68000 kg (149,914.3 lb)
  • Gross liftoff weight (per booster): 571000 kg (1,258,839.5 lb)
  • Thrust (at liftoff, sea level, per booster): 12.5 MN (2,810,111.8 lbf)
  • Specific impulse: 269 s
  • Burn time: 124 s


System Stack specifications
  • Height: 56 m (183.7 ft)
  • Gross liftoff weight: 2000000 kg (4,409,245.2 lb)
  • Total liftoff thrust: 30.16 MN (6,780,237.7 lbf)

Mission profile




Launch



All Space Shuttle missions were launched from Kennedy Space Center (KSC). The weather criteria used for launch included, but were not limited to: precipitation, temperatures, cloud cover, lightning forecast, wind, and humidity. The shuttle was not launched under conditions where it could have been struck by lightning
Lightning
Lightning is an atmospheric electrostatic discharge accompanied by thunder, which typically occurs during thunderstorms, and sometimes during volcanic eruptions or dust storms...

. Aircraft are often struck by lightning with no adverse effects because the electricity of the strike is dissipated through its conductive structure and the aircraft is not electrically grounded
Ground (electricity)
In electrical engineering, ground or earth may be the reference point in an electrical circuit from which other voltages are measured, or a common return path for electric current, or a direct physical connection to the Earth....

. Like most jet airliners, the shuttle was mainly constructed of conductive aluminum, which would normally shield and protect the internal systems. However, upon liftoff the shuttle sent out a long exhaust plume as it ascended, and this plume could have triggered lightning by providing a current path to ground. The NASA Anvil Rule for a shuttle launch stated that an anvil cloud could not appear within a distance of 10 nautical miles. The Shuttle Launch Weather Officer monitored conditions until the final decision to scrub a launch was announced. In addition, the weather conditions had to be acceptable at one of the Transatlantic Abort Landing sites (one of several Space Shuttle abort modes
Space Shuttle abort modes
A Space Shuttle abort was an emergency procedure due to equipment failure on NASA's Space Shuttle, most commonly during ascent. A main engine failure is a typical abort scenario. There are fewer abort options during reentry and descent...

) to launch as well as the solid rocket booster recovery area. While the shuttle might have safely endured a lightning strike, a similar strike caused problems on Apollo 12, so for safety NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...

 chose not to launch the shuttle if lightning was possible (NPR8715.5).

Historically, the Shuttle was not launched if its flight would run from December to January (a year-end rollover or YERO). Its flight software, designed in the 1970s, was not designed for this, and would require the orbiter's computers be reset through a change of year, which could cause a glitch while in orbit. In 2007, NASA engineers devised a solution so Shuttle flights could cross the year-end boundary.

On the day of a launch, after the final hold in the countdown at T-minus 9 minutes, the Shuttle went through its final preparations for launch, and the countdown was automatically controlled by the Ground Launch Sequencer (GLS), software at the Launch Control Center, which stopped the count if it sensed a critical problem with any of the Shuttle's onboard systems. The GLS handed off the count to the Shuttle's on-board computers at T minus 31 seconds, in a process called auto sequence start.

At T-minus 16 seconds, the massive sound suppression system (SPS) began to drench the Mobile Launcher Platform
Mobile Launcher Platform
The Mobile Launcher Platform or MLP is one of three two-story structures used by NASA to support the Space Shuttle stack during its transportation from the Vehicle Assembly Building to Launch Pad 39-A at the Kennedy Space Center as well as serve as the vehicle's launch platform...

 (MLP) and SRB trenches with 350000 gallons (1,324.9 m³) of water to protect the Orbiter from damage by acoustical energy and rocket exhaust reflected from the flame trench and MLP during lift off (NASA article).

At T-minus 10 seconds, hydrogen igniters were activated under each engine bell to quell the stagnant gas inside the cones before ignition. Failure to burn these gases could trip the onboard sensors and create the possibility of an overpressure and explosion of the vehicle during the firing phase. The main engine turbopumps also began charging the combustion chambers with liquid hydrogen and liquid oxygen at this time. The computers reciprocated this action by allowing the redundant computer systems to begin the firing phase.
The three main engines (SSMEs
Space Shuttle main engine
The RS-25, otherwise known as the Space Shuttle Main Engine , is a reusable liquid-fuel rocket engine built by Pratt & Whitney Rocketdyne for the Space Shuttle, running on liquid hydrogen and oxygen. Each Space Shuttle was propelled by three SSMEs mated to one powerhead...

) started at T-minus 6.6 seconds. The main engines ignited sequentially via the shuttle's general purpose computers (GPCs) at 120 millisecond intervals. The GPCs required that the engines reach 90 percent of their rated performance to complete the final gimbal of the main engine nozzles to liftoff configuration. When the SSMEs started, water from the sound suppression system flashed into a large volume of steam that shot southward. All three SSMEs had to reach the required 100 percent thrust within three seconds, otherwise the onboard computers would initiate an RSLS abort. If the onboard computers verified normal thrust buildup, at T minus 0 seconds, the 8 pyrotechnic nuts
Pyrotechnic fastener
A pyrotechnic fastener is a fastener, usually a nut or bolt, that incorporates a pyrotechnic charge that can be initiated remotely. One or more explosive charges embedded within the bolt are typically activated by an electric current, and the charge breaks the bolt into two or more pieces...

 holding the vehicle to the pad were detonated and the SRBs
Space Shuttle Solid Rocket Booster
The Space Shuttle Solid Rocket Boosters were the pair of large solid rockets used by the United States' NASA Space Shuttle during the first two minutes of powered flight. Together they provided about 83% of liftoff thrust for the Space Shuttle. They were located on either side of the rusty or...

 were ignited. At this point the vehicle was committed to liftoff, as the SRBs could not be turned off once ignited. The plume from the solid rockets exited the flame trench in a northward direction at near the speed of sound, often causing a rippling of shockwaves along the actual flame and smoke contrails. At ignition, the GPCs mandated the firing sequences via the Master Events Controller, a computer program integrated with the shuttle's four redundant computer systems. There were extensive emergency procedures (abort modes
Space Shuttle abort modes
A Space Shuttle abort was an emergency procedure due to equipment failure on NASA's Space Shuttle, most commonly during ascent. A main engine failure is a typical abort scenario. There are fewer abort options during reentry and descent...

) to handle various failure scenarios during ascent. Many of these concerned SSME failures, since that was the most complex and highly stressed component. After the Challenger disaster
Space Shuttle Challenger disaster
The Space Shuttle Challenger disaster occurred on January 28, 1986, when Space Shuttle Challenger broke apart 73 seconds into its flight, leading to the deaths of its seven crew members. The spacecraft disintegrated over the Atlantic Ocean, off the coast of central Florida at 11:38 am EST...

, there were extensive upgrades to the abort modes.

After the main engines started, but while the solid rocket boosters were still bolted to the pad, the offset thrust from the Shuttle's three main engines caused the entire launch stack (boosters, tank and shuttle) to pitch down about 2 m at cockpit level. This motion was called the "nod", or "twang" in NASA jargon. As the boosters flexed back into their original shape, the launch stack pitched slowly back upright. This took approximately six seconds. At the point when it was perfectly vertical, the boosters ignited and the launch commenced. The Johnson Space Center's Mission Control Center
Mission Control Center
A mission control center is an entity that manages aerospace vehicle flights, usually from the point of lift-off until the landing or the end of the mission. A staff of flight controllers and other support personnel monitor all aspects of the mission using telemetry, and send commands to the...

 assumed control of the flight once the SRBs had cleared the launch tower.

Shortly after clearing the tower, the Shuttle began a combined roll, pitch and yaw maneuver that positioned the orbiter head down, with wings level and aligned with the launch pad. The Shuttle flew upside down during the ascent phase. This orientation allowed a trim angle of attack that was favorable for aerodynamic loads during the region of high dynamic pressure, resulting in a net positive load factor, as well as providing the flight crew with use of the ground as a visual reference. The vehicle climbed in a progressively flattening arc, accelerating as the weight of the SRBs and main tank decreased. To achieve low orbit requires much more horizontal than vertical acceleration. This was not visually obvious, since the vehicle rose vertically and was out of sight for most of the horizontal acceleration. The near circular orbital velocity at the 380 kilometres (236.1 mi) altitude of the International Space Station
International Space Station
The International Space Station is a habitable, artificial satellite in low Earth orbit. The ISS follows the Salyut, Almaz, Cosmos, Skylab, and Mir space stations, as the 11th space station launched, not including the Genesis I and II prototypes...

 is 7.68 kilometers per second 27650 km/h (17,180.9 mph), roughly equivalent to Mach 23 at sea level. As the International Space Station orbits at an inclination of 51.6 degrees, the Shuttle had to set its inclination to the same value to rendezvous with the station.

Around a point called Max Q
Max Q
In aerospace engineering, the maximum dynamic pressure, often referred to as maximum Q or max Q, is the point at which aerodynamic stress on a vehicle in atmospheric flight is maximized...

, where the aerodynamic forces are at their maximum, the main engines were temporarily throttled back to 72 percent to avoid over-speeding
Overspeed (aircraft)
Overspeed is the aircraft flight condition when the airspeed or ground speed is greater than a maximum speed, e.g.;*never exceed speed*maximum speed for stability characteristics*maximum operating limit speed*maximum flap extended speed...

 and hence overstressing the Shuttle, particularly in vulnerable areas such as the wings. At this point, a phenomenon known as the Prandtl-Glauert singularity
Prandtl-Glauert singularity
The Prandtl–Glauert singularity is the prediction by the Prandtl–Glauert transformation that infinite pressure conditions would be experienced by an aircraft as it approaches the speed of sound. Because it is invalid to apply the transformation at these speeds, the predicted singularity does not...

 occurred, where condensation clouds formed during the vehicle's transition to supersonic speed. At T+70 seconds, the main engines throttled up to their maximum cruise thrust of 104% rated thrust.
At
T+126 seconds after launch, explosive bolts released the SRBs and small separation rockets pushed them laterally away from the vehicle. The SRBs parachuted back to the ocean to be reused. The Shuttle then began accelerating to orbit on the main engines. The vehicle at that point in the flight had a thrust-to-weight ratio of less than one the main engines actually had insufficient thrust to exceed the force of gravity, and the vertical speed given to it by the SRBs temporarily decreased. However, as the burn continued, the weight of the propellant decreased and the thrust-to-weight ratio exceeded 1 again and the ever-lighter vehicle then continued to accelerate towards orbit.

The vehicle continued to climb and take on a somewhat nose-up angle to the horizon it used the main engines to gain and then maintain altitude while it accelerated horizontally towards orbit. At about five and three-quarter minutes into ascent, the orbiter's direct communication links with the ground began to fade, at which point it rolled heads up to reroute its communication links to the Tracking and Data Relay Satellite
Tracking and Data Relay Satellite
A Tracking and Data Relay Satellite is a type of communications satellite that forms part of the Tracking and Data Relay Satellite System used by NASA and other United States government agencies for communications to and from independent "User Platforms" such as satellites, balloons, aircraft,...

 system.

Finally, in the last tens of seconds of the main engine burn, the mass of the vehicle was low enough that the engines had to be throttled back to limit vehicle acceleration to 3 g (29.34 m/s²), largely for astronaut comfort. At approximately eight minutes post launch, the main engines were shut down.

The main engines were shut down before complete depletion of propellant, as running dry would have destroyed the engines. The oxygen supply was terminated before the hydrogen supply, as the SSMEs reacted unfavorably to other shutdown modes. (Liquid oxygen has a tendency to react violently, and supports combustion when it encounters hot engine metal.) The external tank was released by firing explosive bolts, largely burning up in the atmosphere, though some fragments fell into the ocean, in either the Indian Ocean or the Pacific Ocean depending on launch profile. The sealing action of the tank plumbing and lack of pressure relief systems on the external tank helped it break up in the lower atmosphere. After the foam burned away during re-entry, the heat caused a pressure buildup in the remaining liquid oxygen and hydrogen until the tank exploded. This ensured that any pieces that fell back to Earth were small.

To prevent the shuttle from following the external tank back into the lower atmosphere, the Orbital maneuvering system (OMS) engines were fired to raise the perigee higher into the upper atmosphere. On some missions (e.g., missions to the ISS), the OMS engines were also used while the main engines were still firing. The reason for putting the orbiter on a path that brought it back to Earth was not just for external tank disposal but also one of safety: if the OMS malfunctioned, or the cargo bay doors could not open for some reason, the shuttle was already on a path to return to earth for an emergency abort landing.

Ascent tracking


The shuttle was monitored throughout its ascent for short range tracking (10 seconds before liftoff through 57 seconds after), medium range (7 seconds before liftoff through 110 seconds after) and long range (7 seconds before liftoff through 165 seconds after). Short range cameras included 22 16mm cameras on the Mobile Launch Platform and 8 16mm on the Fixed Service Structure, 4 high speed fixed cameras located on the perimeter of the launch complex plus and additional 42 fixed cameras with 16mm motion picture film. Medium range cameras included remotely operated tracking cameras at the launch complex plus 6 sites along the immediate coast north and south of the launch pad, each with 800mm lens and high speed cameras running 100 feet per second. These cameras ran for only 4–10 seconds due to limitations in the amount of film available. Long range cameras included those mounted on the External Tank, SRBs and orbiter itself which streamed live video back to the ground providing valuable information about any debris falling during ascent. Long range tracking cameras with 400-inch film and 200-inch video lenses were operated by a photographer at Playalinda Beach
Playalinda Beach
Playalinda Beach is a beach located on Florida's east coast in Canaveral National Seashore. When translated from Spanish, Playa linda is "pretty beach". The beach is open to the public daily between 6:00 am to 6:00 pm in the winter and 6:00 am to 8:00 pm in the summer...

 as well as 9 other sites from 38 miles north at the Ponce Inlet to 23 miles south to Patrick Air Force Base
Patrick Air Force Base
Patrick Air Force Base is a United States Air Force Base located between Satellite Beach and Cocoa Beach, in Brevard County, Florida, United States. It was named in honor of Major General Mason Patrick. An Air Force Space Command base, it is home to the 45th Space Wing...

 (PAFB) and additional mobile optical tracking camera was stationed on Merritt Island during launches. A total of 10 HD cameras were used both for ascent information for engineers and broadcast feeds to networks such as NASA TV
NASA TV
NASA TV is the television service of the United States government agency NASA. NASA TV is broadcast by satellite with a simulcast over the Internet. Local cable television systems across the U.S. and amateur television repeaters may carry NASA TV at their discretion, as NASA-created content is...

 and HDNet
HDNet
HDNet is a men's interest television channel in the United States, broadcasting exclusively in high-definition format and available via cable and satellite television...

 The number of cameras significantly increased and numerous existing cameras were upgraded at the recommendation of the Columbia Accident Investigation Board
Columbia Accident Investigation Board
The Columbia Accident Investigation Board was convened by NASA to investigate the destruction of the Space Shuttle Columbia during STS-107 upon atmospheric re-entry on February 1, 2003. In addition to determining the cause of the accident, the panel also recommended changes that should be made...

 to provide better information about the debris during launch. Debris was also tracked using a pair of Weibel
Weibel
Weibel is a Danish designer and manufacturer of doppler radars. It is located in Allerød, Denmark. All Weibel radars operate in the X band and are continuous wave doppler radars. NASA recently purchased some of Weibel's radars, and uses them to detect debris coming off the space shuttle during...

 Continuous Pulse Doppler X-band radars, one on board the SRB recovery ship MV Liberty Star
MV Liberty Star
-References:*-External links:*...

 positioned north east of the launch pad and on a ship positioned south of the launch pad. Additionally, during the first 2 flights following the loss of Columbia and her crew, a pair of NASA WB-57 reconnaissance aircraft equipped with HD Video and Infrared flew at 60000 feet (18,288 m) to provide additional views of the launch ascent. Kennedy Space Center also invested nearly $3 million in improvements to the digital video analysis systems in support of debris tracking.

In orbit


Once in orbit, the Shuttle usually flew at an altitude of 200 miles (321.9 km), and occasionally as high as 400 miles. In the 1980s and 1990s, many flights involved space science missions on the NASA/ESA Spacelab
Spacelab
Spacelab was a reusable laboratory used on certain spaceflights flown by the Space Shuttle. The laboratory consisted of multiple components, including a pressurized module, an unpressurized carrier and other related hardware housed in the Shuttle's cargo bay...

, or launching various types of satellites and science probes. By the 1990s and 2000s the focus shifted more to servicing space stations, with fewer satellite launches. Most missions involved staying in orbit several days to two weeks, although longer missions were possible with the Extended Duration Orbiter
Extended Duration Orbiter
The Extended Duration Orbiter program was a project by NASA to prepare for long-term microgravity research aboard Space Station Freedom, which later evolved into the International Space Station. Scientists and NASA needed practical experience in managing progressively longer times for their...

 add-on or when attached to a space station.

Re-entry and landing


Almost the entire Space Shuttle re-entry procedure, except for lowering the landing gear and deploying the air data probes, were normally performed under computer control. However, the re-entry could be flown entirely manually if an emergency arose. The approach and landing phase could be controlled by the autopilot, but was usually hand flown.
The vehicle began re-entry by firing the Orbital maneuvering system engines, while flying upside down, backside first, in the opposite direction to orbital motion for approximately three minutes, which reduced the shuttle's velocity by about 200 mph (321.9 km/h). The resultant slowing of the Shuttle lowered its orbital perigee
Perigee
Perigee is the point at which an object makes its closest approach to the Earth.. Often the term is used in a broader sense to define the point in an orbit where the orbiting body is closest to the body it orbits. The opposite is the apogee, the farthest or highest point.The Greek prefix "peri"...

 down into the upper atmosphere. The shuttle then flipped over, by pushing its nose down (which was actually "up" relative to the Earth, because it was flying upside down). This OMS firing was done roughly halfway around the globe from the landing site.

The vehicle started encountering more significant air density in the lower thermosphere at about 400000 ft (121.9 km), at around Mach
Mach number
Mach number is the speed of an object moving through air, or any other fluid substance, divided by the speed of sound as it is in that substance for its particular physical conditions, including those of temperature and pressure...

 25, 8200 m/s (29,520 km/h; 18,342.9 mph). The vehicle was controlled by a combination of RCS thrusters
Reaction control system
A reaction control system is a subsystem of a spacecraft whose purpose is attitude control and steering by the use of thrusters. An RCS system is capable of providing small amounts of thrust in any desired direction or combination of directions. An RCS is also capable of providing torque to allow...

 and control surfaces, to fly at a 40 degree nose-up attitude, producing high drag, not only to slow it down to landing speed, but also to reduce reentry heating. As the vehicle encountered progressively denser air, it began a gradual transition from spacecraft to aircraft. In a straight line, its 40 degree nose-up attitude would cause the descent angle to flatten-out, or even rise. The vehicle therefore performed a series of four steep S-shaped banking turns, each lasting several minutes, at up to 70 degrees of bank, while still maintaining the 40 degree angle of attack. In this way it dissipated speed sideways rather than upwards. This occurred during the 'hottest' phase of re-entry, when the heat-shield glowed red and the G-forces were at their highest. By the end of the last turn, the transition to aircraft was almost complete. The vehicle leveled its wings, lowered its nose into a shallow dive and began its approach to the landing site.



The orbiter's maximum glide ratio/lift-to-drag ratio
Lift-to-drag ratio
In aerodynamics, the lift-to-drag ratio, or L/D ratio, is the amount of lift generated by a wing or vehicle, divided by the drag it creates by moving through the air...

 varies considerably with speed, ranging from 1:1 at hypersonic
Hypersonic
In aerodynamics, a hypersonic speed is one that is highly supersonic. Since the 1970s, the term has generally been assumed to refer to speeds of Mach 5 and above...

 speeds, 2:1 at supersonic speeds and reaching 4.5:1 at subsonic speeds during approach and landing.

In the lower atmosphere, the orbiter flies much like a conventional glider, except for a much higher descent rate, over 50 m/s (180 km/h; 111.8 mph)(9800fpm). At approximately Mach 3, two air data probes, located on the left and right sides of the orbiter's forward lower fuselage, are deployed to sense air pressure related to the vehicle's movement in the atmosphere.

Final approach and landing phase


When the approach and landing phase began, the orbiter was at a 3000 m (9,842.5 ft) altitude, 12 km (7.5 mi) from the runway. The pilots applied aerodynamic braking to help slow down the vehicle. The orbiter's speed was reduced from 682 to 346 km/h (423.8 to 215 mph), approximately, at touch-down (compared to 260 km/h (161.6 mph) for a jet airliner). The landing gear was deployed while the Orbiter was flying at 430 km/h (267.2 mph). To assist the speed brakes, a 12 m (39.4 ft) drag chute was deployed either after main gear or nose gear touchdown (depending on selected chute deploy mode) at about 343 km/h (213.1 mph). The chute was jettisoned once the orbiter slowed to 110 km/h (68.4 mph).

Post-landing processing


After landing, the vehicle stayed on the runway for several minutes for the orbiter to cool. Teams at the front and rear of the orbiter tested for presence of hydrogen
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...

, hydrazine
Hydrazine
Hydrazine is an inorganic compound with the formula N2H4. It is a colourless flammable liquid with an ammonia-like odor. Hydrazine is highly toxic and dangerously unstable unless handled in solution. Approximately 260,000 tons are manufactured annually...

, monomethylhydrazine
Monomethylhydrazine
Monomethylhydrazine is a volatile hydrazine chemical with the chemical formula CH3 NH2. It is used as a rocket propellant in bipropellant rocket engines because it is hypergolic with various oxidizers such as nitrogen tetroxide and nitric acid...

, nitrogen tetroxide and ammonia
Ammonia
Ammonia is a compound of nitrogen and hydrogen with the formula . It is a colourless gas with a characteristic pungent odour. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers. Ammonia, either directly or...

 (fuels and by products of the control
Reaction control system
A reaction control system is a subsystem of a spacecraft whose purpose is attitude control and steering by the use of thrusters. An RCS system is capable of providing small amounts of thrust in any desired direction or combination of directions. An RCS is also capable of providing torque to allow...

 and the orbiter's three APUs
Auxiliary power unit
An auxiliary power unit is a device on a vehicle that provides energy for functions other than propulsion. They are commonly found on large aircraft, as well as some large land vehicles.-Function:...

). If hydrogen was detected, an emergency would be declared, the orbiter powered down and teams would evacuate the area. A convoy of 25 specially-designed vehicles and 150 trained engineers and technicians approached the orbiter. Purge and vent lines were attached to remove toxic gasses from fuel lines and the cargo bay about 45–60 minutes after landing. A flight surgeon
Flight surgeon
A flight surgeon is a military medical officer assigned to duties in the clinical field variously known as aviation medicine, aerospace medicine, or flight medicine...

 boarded the orbiter for initial medical checks of the crew before disembarking. Once the crew left the orbiter, responsibility for the vehicle was handed from the Johnson Space Center back to the Kennedy Space Center

If the mission ended at Edwards Air Force Base
Edwards Air Force Base
Edwards Air Force Base is a United States Air Force base located on the border of Kern County, Los Angeles County, and San Bernardino County, California, in the Antelope Valley. It is southwest of the central business district of North Edwards, California and due east of Rosamond.It is named in...

 in California, White Sands Space Harbor
White Sands Space Harbor
White Sands Space Harbor is the primary training area used by NASA for Space Shuttle pilots flying practice approaches and landings in the Shuttle Training Aircraft and T-38 Talon aircraft. Its runways, navigational aids, runway lighting, and control facilities also stand continuously ready as a...

 in New Mexico, or any of the runways the orbiter might use in an emergency, the orbiter was loaded atop the Shuttle Carrier Aircraft
Shuttle Carrier Aircraft
The Shuttle Carrier Aircraft are two extensively modified Boeing 747 airliners that NASA uses to transport Space Shuttle orbiters...

, a modified 747, for transport back to the Kennedy Space Center, landing at the Shuttle Landing Facility. Once at the Shuttle Landing Facility, the orbiter was then towed 2 miles (3.2 km) along a tow-way and access roads normally used by tour busses and KSC employees to the Orbiter Processing Facility
Orbiter Processing Facility
An Orbiter Processing Facility was one of three hangars where U.S. space shuttle orbiters underwent maintenance between flights. All three such facilities, OPF-1, OPF-2 and OPF-3, were located at NASA's Kennedy Space Center in Florida at Launch Complex 39.They were located west of the Vehicle...

 where it began a months-long preparation process for the next mission.

Landing sites


NASA preferred Space Shuttle landings to be at Kennedy Space Center
Kennedy Space Center
The John F. Kennedy Space Center is the NASA installation that has been the launch site for every United States human space flight since 1968. Although such flights are currently on hiatus, KSC continues to manage and operate unmanned rocket launch facilities for America's civilian space program...

. If weather conditions made landing there unfavorable, the shuttle could delay its landing until conditions are favorable, touch down at Edwards Air Force Base, California, or use one of the multiple alternate landing sites around the world. A landing at any site other than Kennedy Space Center meant that after touchdown the shuttle must be mated to the Shuttle Carrier Aircraft
Shuttle Carrier Aircraft
The Shuttle Carrier Aircraft are two extensively modified Boeing 747 airliners that NASA uses to transport Space Shuttle orbiters...

 and returned to Cape Canaveral
Cape Canaveral
Cape Canaveral, from the Spanish Cabo Cañaveral, is a headland in Brevard County, Florida, United States, near the center of the state's Atlantic coast. Known as Cape Kennedy from 1963 to 1973, it lies east of Merritt Island, separated from it by the Banana River.It is part of a region known as the...

. Space Shuttle Columbia (STS-3
STS-3
STS-3 was NASA's third Space Shuttle mission, and was the third mission for the Space Shuttle Columbia. It was the first shuttle launch with an unpainted external tank, and the only mission to land at the White Sands Space Harbor near Las Cruces, New Mexico.-Crew:-Backup crew:-Mission...

) landed at the White Sands Space Harbor
White Sands Space Harbor
White Sands Space Harbor is the primary training area used by NASA for Space Shuttle pilots flying practice approaches and landings in the Shuttle Training Aircraft and T-38 Talon aircraft. Its runways, navigational aids, runway lighting, and control facilities also stand continuously ready as a...

, New Mexico
New Mexico
New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...

; this was viewed as a last resort as NASA scientists believe that the sand could potentially damage the shuttle's exterior.

There were many alternative landing sites that were never used.

Risk contributors



An example of technical risk analysis for a STS mission is SPRA iteration 3.1 top risk contributors for STS-133:
  1. Micro-Meteoroid Orbital Debris (MMOD) strikes
  2. Space Shuttle Main Engine (SSME)-induced or SSME catastrophic failure
  3. Ascent debris strikes to TPS leading to LOCV on orbit or entry
  4. Crew error during entry
  5. RSRM-induced RSRM catastrophic failure (RSRM are the rocket motors of the Solid Rocket Boosters)
  6. COPV failure (COPV are tanks inside the orbiter that hold gas at high pressure)


An internal NASA risk assessment study (conducted by the Shuttle Program Safety and Mission Assurance Office at Johnson Space Center
Lyndon B. Johnson Space Center
The Lyndon B. Johnson Space Center is the National Aeronautics and Space Administration's center for human spaceflight training, research and flight control. The center consists of a complex of 100 buildings constructed on 1,620 acres in Houston, Texas, USA...

) released in late 2010 or early 2011 concluded that the agency had seriously underestimated the level of risk involved in operating the shuttle. The report assessed that there was a 1 in 9 chance of a catastrophic disaster during the first nine flights of the shuttle but that safety improvements had later improved the risk ratio to 1 in 100.

Fleet history


Below is a list of major events in the Space Shuttle orbiter fleet.
Space Shuttle major events
Date Orbiter Major event / remarks
September 17, 1976 Enterprise
Space Shuttle Enterprise
The Space Shuttle Enterprise was the first Space Shuttle orbiter. It was built for NASA as part of the Space Shuttle program to perform test flights in the atmosphere. It was constructed without engines or a functional heat shield, and was therefore not capable of spaceflight...

Prototype Space Shuttle Enterprise
Space Shuttle Enterprise
The Space Shuttle Enterprise was the first Space Shuttle orbiter. It was built for NASA as part of the Space Shuttle program to perform test flights in the atmosphere. It was constructed without engines or a functional heat shield, and was therefore not capable of spaceflight...

 was rolled out of its assembly facility in Southern California and displayed before a crowd several thousand strong.
February 18, 1977 Enterprise
Space Shuttle Enterprise
The Space Shuttle Enterprise was the first Space Shuttle orbiter. It was built for NASA as part of the Space Shuttle program to perform test flights in the atmosphere. It was constructed without engines or a functional heat shield, and was therefore not capable of spaceflight...

First flight; Attached to Shuttle Carrier Aircraft
Shuttle Carrier Aircraft
The Shuttle Carrier Aircraft are two extensively modified Boeing 747 airliners that NASA uses to transport Space Shuttle orbiters...

 throughout flight.
August 12, 1977 Enterprise First free flight; Tailcone on; lakebed landing.
October 26, 1977 Enterprise Final Enterprise free flight; First landing on Edwards AFB concrete runway.
April 12, 1981 Columbia
Space Shuttle Columbia
Space Shuttle Columbia was the first spaceworthy Space Shuttle in NASA's orbital fleet. First launched on the STS-1 mission, the first of the Space Shuttle program, it completed 27 missions before being destroyed during re-entry on February 1, 2003 near the end of its 28th, STS-107. All seven crew...

First Columbia flight, first orbital test flight; STS-1
STS-1
STS-1 was the first orbital flight of NASA's Space Shuttle program. Space Shuttle Columbia launched on 12 April 1981, and returned to Earth on 14 April, having orbited the Earth 37 times during the 54.5-hour mission. It was the first American manned space flight since the Apollo-Soyuz Test Project...

November 11, 1982 Columbia First operational flight of the Space Shuttle, first mission to carry four astronauts; STS-5
STS-5
STS-5 was a NASA Space Shuttle mission, the fifth shuttle mission overall and the fifth flight of the Space Shuttle Columbia. It was the first shuttle mission to deploy communications satellites into orbit...

April 4, 1983 Challenger
Space Shuttle Challenger
Space Shuttle Challenger was NASA's second Space Shuttle orbiter to be put into service, Columbia having been the first. The shuttle was built by Rockwell International's Space Transportation Systems Division in Downey, California...

First Challenger flight; STS-6
STS-6
STS-6 was a NASA Space Shuttle mission conducted using Space Shuttle Challenger, carrying the first Tracking and Data Relay Satellite, TDRS-1, into orbit. Launched on 4 April 1983, STS-6 was the sixth shuttle mission and the first of the ten missions flown by Challenger...

August 30, 1984 Discovery
Space Shuttle Discovery
Space Shuttle Discovery is one of the retired orbiters of the Space Shuttle program of NASA, the space agency of the United States, and was operational from its maiden flight, STS-41-D on August 30, 1984, until its final landing during STS-133 on March 9, 2011...

First Discovery flight; STS-41-D
STS-41-D
STS-41-D was the first flight of NASA's Space Shuttle orbiter Discovery. It was the 12th mission of the Space Shuttle program, and was launched from Kennedy Space Center, Florida, on 30 August 1984...

October 3, 1985 Atlantis
Space Shuttle Atlantis
The Space Shuttle Atlantis is a retired Space Shuttle orbiter in the Space Shuttle fleet belonging to the National Aeronautics and Space Administration , the spaceflight and space exploration agency of the United States...

First Atlantis flight; STS-51-J
STS-51-J
STS-51-J was a NASA Space Shuttle mission. It was the first flight of Space Shuttle Atlantis and the 21st shuttle mission overall. It launched from Kennedy Space Center, Florida, on 3 October 1985, carrying a payload for the U.S...

October 30, 1985 Challenger First crew of eight astronauts; STS-61-A
STS-61-A
STS-61-A was the 22nd mission of NASA's Space Shuttle program. It was a scientific Spacelab mission, funded and directed by West Germany – hence the non-NASA designation of D-1 . STS-61-A was the last successful mission of the Space Shuttle Challenger, which was destroyed during STS-51-L in 1986...

January 28, 1986 Challenger Disaster starting 73 seconds after launch
Space Shuttle Challenger disaster
The Space Shuttle Challenger disaster occurred on January 28, 1986, when Space Shuttle Challenger broke apart 73 seconds into its flight, leading to the deaths of its seven crew members. The spacecraft disintegrated over the Atlantic Ocean, off the coast of central Florida at 11:38 am EST...

; STS-51-L
STS-51-L
STS-51-L was the twenty-fifth flight of the American Space Shuttle program, which marked the first time an ordinary civilian, schoolteacher Christa McAuliffe, had flown aboard the Space Shuttle. The mission used Space Shuttle Challenger, which lifted off from the Launch Complex 39-B on 28 January...

; all seven crew members died.
September 29, 1988 Discovery First post-Challenger mission; STS-26
STS-26
STS-26 was the 26th NASA Space Shuttle mission and the seventh flight of the Discovery orbiter. The mission launched from Kennedy Space Center, Florida, on 29 September 1988, and landed four days later on 3 October. STS-26 was declared the "Return to Flight" mission, being the first mission after...

May 4, 1989 Atlantis The first Space Shuttle mission to launch a space probe, Magellan
Magellan probe
The Magellan spacecraft, also referred to as the Venus Radar Mapper, was a 1,035-kilogram robotic space probe launched by NASA on May 4, 1989, to map the surface of Venus using Synthetic Aperture Radar and measure the planetary gravity...

; STS-30
STS-30
STS-30 was a NASA Space Shuttle mission, during which Space Shuttle Atlantis deployed the Venus-bound Magellan probe into orbit. The mission launched from Kennedy Space Center, Florida, on 4 May 1989, and landed four days later...

April 24, 1990 Discovery Launch of the Hubble Space Telescope
Hubble Space Telescope
The Hubble Space Telescope is a space telescope that was carried into orbit by a Space Shuttle in 1990 and remains in operation. A 2.4 meter aperture telescope in low Earth orbit, Hubble's four main instruments observe in the near ultraviolet, visible, and near infrared...

; STS-31
STS-31
STS-31 was the thirty-fifth mission of the American Space Shuttle program, which launched the Hubble Space Telescope astronomical observatory into Earth orbit...

May 7, 1992 Endeavour
Space Shuttle Endeavour
Space Shuttle Endeavour is one of the retired orbiters of the Space Shuttle program of NASA, the space agency of the United States. Endeavour was the fifth and final spaceworthy NASA space shuttle to be built, constructed as a replacement for Challenger...

First Endeavour flight; STS-49
STS-49
-Mission parameters:*Mass:**Orbiter landing with payload: **Payload: *Perigee: *Apogee: *Inclination: 28.35°*Period: 90.6 min-Space walks:* Thuot and Hieb – EVA 1*EVA 1 Start: 10 May 1992 – 20:40 UTC...

November 19, 1996 Columbia Longest Shuttle mission at 17 days, 15 hours; STS-80
STS-80
-Mission parameters:* Mass: payload* Perigee: * Apogee: * Inclination: 28.5°* Period: 91.5 min-Mission highlights:* The mission deployed two satellites and successfully recovered them after they had performed their tasks....

December 4, 1998 Endeavour First ISS
ISS
The ISS is the International Space Station.ISS may also refer to:* I See Stars, an American electronic rock band* ISS A/S, a Danish service company* Idea Star Singer, a Malayalam music reality show by Asianet TV...

 mission; STS-88
STS-88
-Mission parameters:*Weight*Liftoff: *Landing: *Perigee: *Apogee: *Orbital Period: 92.4min-Launch attempts:-Mission highlights:Node 1, named Unity, was the first space station hardware delivered by the space shuttle. It has two Pressurized Mating Adapters , one attached to either end...

February 1, 2003 Columbia Disintegrated during re-entry
Space Shuttle Columbia disaster
The Space Shuttle Columbia disaster occurred on February 1, 2003, when shortly before it was scheduled to conclude its 28th mission, STS-107, the Space Shuttle Columbia disintegrated over Texas and Louisiana during re-entry into the Earth's atmosphere, resulting in the death of all seven crew members...

; STS-107
STS-107
-Mission parameters:*Mass:**Orbiter Liftoff: **Orbiter Landing: **Payload: *Perigee: *Apogee: *Inclination: 39.0°*Period: 90.1 min- Insignia :...

; all seven crew members died.
July 25, 2005 Discovery First post-Columbia mission; STS-114
STS-114
-Original crew:This mission was to carry the Expedition 7 crew to the ISS and bring home the Expedition 6 crew. The original crew was to be:-Mission highlights:...

February 24, 2011 Discovery Last Discovery flight; STS-133
STS-133
STS-133 was the 133rd mission in NASA's Space Shuttle program; during the mission, Space Shuttle Discovery docked with the International Space Station. It was Discoverys 39th and final mission. The mission launched on 24 February 2011, and landed on 9 March 2011...

May 16, 2011 Endeavour Last Endeavour mission; STS-134
STS-134
STS-134 was the penultimate mission of NASA's Space Shuttle program. The mission marked the 25th and final flight of . This flight delivered the Alpha Magnetic Spectrometer and an ExPRESS Logistics Carrier to the International Space Station. Mark Kelly served as the mission commander...

July 8, 2011 Atlantis Last Atlantis flight and last Space Shuttle flight; STS-135
STS-135
STS-135 was the final mission of the American Space Shuttle program. It used the orbiter Atlantis and hardware originally processed for the STS-335 contingency mission, which was not flown. STS-135 launched on 8 July and was originally scheduled to land on 20 July 2011, but the mission was...


Sources: NASA launch manifest, NASA Space Shuttle archive

Shuttle disasters


On January 28, 1986, Challenger disintegrated 73 seconds after launch due to the failure of the right SRB, killing all seven astronauts on board. The disaster was caused by low-temperature impairment of an O-ring, a mission critical seal used between segments of the SRB casing. The failure of a lower O-ring seal allowed hot combustion gases to escape from between the booster sections and burn through the adjacent external tank
Space Shuttle external tank
A Space Shuttle External Tank is the component of the Space Shuttle launch vehicle that contains the liquid hydrogen fuel and liquid oxygen oxidizer. During lift-off and ascent it supplies the fuel and oxidizer under pressure to the three Space Shuttle Main Engines in the orbiter...

, causing it to disintegrate. Repeated warnings from design engineers voicing concerns about the lack of evidence of the O-rings' safety when the temperature was below 53 °F (12 °C) had been ignored by NASA managers.

On February 1, 2003, Columbia disintegrated during re-entry, killing its crew of seven, because of damage to the carbon-carbon
Reinforced carbon-carbon
Carbon fibre-reinforced carbon is a composite material consisting of carbon fibre reinforcement in a matrix of graphite. It was developed for the nose cones of intercontinental ballistic missiles, and is most widely known as the material for the nose cone and wing leading edges of the Space Shuttle...

 leading edge of the wing caused during launch. Ground control engineers had made three separate requests for high-resolution images taken by the Department of Defense that would have provided an understanding of the extent of the damage, while NASA's chief thermal protection system
Space Shuttle thermal protection system
The Space Shuttle thermal protection system is the barrier that protects the Space Shuttle Orbiter during the searing heat of atmospheric reentry...

 (TPS) engineer requested that astronauts on board Columbia be allowed to leave the vehicle to inspect the damage. NASA managers intervened to stop the Department of Defense's assistance and refused the request for the spacewalk, and thus the feasibility of scenarios for astronaut repair or rescue by Atlantis were not considered by NASA management at the time.

Retirement


NASA retired the Space Shuttle in 2011, after 30 years of service.
Discovery was the first of NASA's three remaining operational Space Shuttles to be retired. Michael Suffredini of the ISS program said that one additional trip was needed in 2011 to deliver parts to the International Space Station.

The final Space Shuttle mission was originally scheduled for late 2010, but the program was later extended to July 2011. Its final mission consisted of just four astronauts—Christopher Ferguson (Commander), Douglas Hurley (Pilot), Sandra Magnus (Mission Specialist 1), and Rex Walheim (Mission Specialist 2); they conducted the 135th and last space shuttle mission on board Atlantis, which launched on July 8, 2011 and landed safely at the Kennedy Space Center on July 21, 2011 at 5:57 AM EDT (09:57 UTC).

Distribution of orbiters and other hardware


NASA announced it would transfer space-worthy orbiters to education institutions or museums at the conclusion of the space shuttle program. Each museum or institution is responsible for covering the cost of preparing and transporting each vehicle for display. Twenty museums from across the country submitted proposals for receiving one of the retired orbiters. NASA also made Space Shuttle thermal protection system
Space Shuttle thermal protection system
The Space Shuttle thermal protection system is the barrier that protects the Space Shuttle Orbiter during the searing heat of atmospheric reentry...

 tiles available to schools and universities for less than US$25 each. About 7,000 tiles were available on a first-come, first-served
First-come, first-served
First-come, first-served – sometimes first-in, first-served and first-come, first choice – is a service policy whereby the requests of customers or clients are attended to in the order that they arrived, without other biases or preferences. The policy can be employed when processing sales orders,...

 basis, limited to one per institution.

On April 12, 2011, NASA announced selection of locations for the remaining Shuttle orbiters:
  • Atlantis
    Space Shuttle Atlantis
    The Space Shuttle Atlantis is a retired Space Shuttle orbiter in the Space Shuttle fleet belonging to the National Aeronautics and Space Administration , the spaceflight and space exploration agency of the United States...

    will be on display at the Kennedy Space Center Visitor Complex
    Kennedy Space Center Visitor Complex
    The Kennedy Space Center Visitor Complex is the visitor center at NASA's Kennedy Space Center in Florida. It features exhibits and displays, historic spacecraft and memorabilia, shows, two IMAX theaters, a range of bus tours of the spaceport, and the Shuttle Launch Experience, a simulated ride into...

    , near Cape Canaveral
    Cape Canaveral
    Cape Canaveral, from the Spanish Cabo Cañaveral, is a headland in Brevard County, Florida, United States, near the center of the state's Atlantic coast. Known as Cape Kennedy from 1963 to 1973, it lies east of Merritt Island, separated from it by the Banana River.It is part of a region known as the...

    , Florida.

  • Discovery
    Space Shuttle Discovery
    Space Shuttle Discovery is one of the retired orbiters of the Space Shuttle program of NASA, the space agency of the United States, and was operational from its maiden flight, STS-41-D on August 30, 1984, until its final landing during STS-133 on March 9, 2011...

    will be delivered to the Udvar-Hazy Center
    Steven F. Udvar-Hazy Center
    The Steven F. Udvar-Hazy Center is the Smithsonian National Air and Space Museum 's annex at Washington Dulles International Airport in the Chantilly area of Fairfax County, Virginia, United States....

     of the Smithsonian Institution
    Smithsonian Institution
    The Smithsonian Institution is an educational and research institute and associated museum complex, administered and funded by the government of the United States and by funds from its endowment, contributions, and profits from its retail operations, concessions, licensing activities, and magazines...

    's National Air and Space Museum
    National Air and Space Museum
    The National Air and Space Museum of the Smithsonian Institution holds the largest collection of historic aircraft and spacecraft in the world. It was established in 1976. Located in Washington, D.C., United States, it is a center for research into the history and science of aviation and...

     in Chantilly, Virginia
    Chantilly, Virginia
    Chantilly is an unincorporated community located in western Fairfax County and southeastern Loudoun County of Northern Virginia. Recognized by the U.S. Census Bureau as a census designated place , the community population was 23,039 as of the 2010 census -- down from 41,041 in 2000, due to the...

    , near Washington, D.C.

  • Endeavour
    Space Shuttle Endeavour
    Space Shuttle Endeavour is one of the retired orbiters of the Space Shuttle program of NASA, the space agency of the United States. Endeavour was the fifth and final spaceworthy NASA space shuttle to be built, constructed as a replacement for Challenger...

    will be delivered to the California Science Center
    California Science Center
    The California Science Center is a state agency and museum located in Exposition Park, Los Angeles. Billed as the West Coast's largest hands-on science center, the California ScienCenter is a public-private partnership between the State and the California Science Center Foundation...

     in Los Angeles, California.

  • Enterprise
    Space Shuttle Enterprise
    The Space Shuttle Enterprise was the first Space Shuttle orbiter. It was built for NASA as part of the Space Shuttle program to perform test flights in the atmosphere. It was constructed without engines or a functional heat shield, and was therefore not capable of spaceflight...

     (atmospheric test orbiter), currently on display at the National Air and Space Museum's Udvar-Hazy Center, will be moved to the Intrepid Sea-Air-Space Museum
    Intrepid Sea-Air-Space Museum
    The Intrepid Sea-Air-Space Museum is a military and maritime history museum with a collection of museum ships in New York City. It is located at Pier 86 at 46th Street on the West Side of Manhattan. The museum showcases the World War II aircraft carrier USS Intrepid, the submarine , a Concorde...

     in New York City, New York.


Flight and mid-deck training hardware will be taken from the Johnson Space Center and will go to the National Air and Space Museum and the National Museum of the U.S. Air Force. The full fuselage mockup, which includes the payload bay and aft section but no wings, is to go to the Museum of Flight
Museum of Flight
The Museum of Flight is a private non-profit air and space museum at King County International Airport , south of downtown Seattle, Washington. It was established in 1965 and is fully accredited by the American Association of Museums...

 in Seattle. Mission Simulation and Training Facility's fixed simulator will go to the Adler Planetarium
Adler Planetarium
The Adler Planetarium & Astronomy Museum in Chicago, Illinois was the first planetarium built in the Western Hemisphere and is the oldest in existence today. Adler was founded and built in 1930 by the philanthropist Max Adler, with the assistance of the first director of the planetarium, Philip Fox...

 in Chicago, and the motion simulator will go to the Texas A&M Aerospace Engineering Department in College Station, Texas. Other simulators used in shuttle astronaut training will go to the Wings of Dreams Aviation Museum
Wings of Dreams Aviation Museum
Wings of Dreams is an aviation museum located at the Keystone Heights Airport in Starke, Florida. The museum features exhibits on the airport's role as Keystone Army Air Base and training of pilots in preparation for the Normandy Invasion during World War II. It also features exhibits on Women...

 in Starke, Florida and the Virginia Air and Space Center
Virginia Air and Space Center
The Virginia Air and Space Center is a museum and educational facility in Hampton, Virginia that also serves as the visitors center for NASA's Langley Research Center...

 in Hampton, Virginia.

In August 2011, the NASA Office of Inspector General
NASA Office of Inspector General
The NASA Office of Inspector General is the inspector general office in the National Aeronautics and Space Administration, the space agency of the United States...

 (OIG) published a "Review of NASA's Selection of Display Locations for the Space Shuttle Orbiters"; the review had four main findings:
  • "NASA's decisions regarding Orbiter placement were the result of an Agency-created process that emphasized above all other considerations locating the Orbiters in places where the most people would have the opportunity to view them";
  • "the Team made several errors during its evaluation process, including one that would have resulted in a numerical 'tie' among the Intrepid, the Kennedy Visitor Complex, and the National Museum of the U.S. Air Force (Air Force Museum) in Dayton, Ohio";
  • there is "no evidence that the Team’s recommendation or the Administrator's decision were tainted by political influence or any other improper consideration";
  • "some of the choices NASA made during the selection process – specifically, its decision to manage aspects of the selection as if it were a competitive procurement and to delay announcement of its placement decisions until April 2011 (more than 2 years after it first solicited information from interested entities)—may intensify challenges to the Agency and the selectees as they work to complete the process of placing the Orbiters in their new homes."

The NASA OIG had three recommendations, saying NASA should:
  • "expeditiously review recipients' financial, logistical, and curatorial display plans to ensure they are feasible and consistent with the Agency's educational goals and processing and delivery schedules";
  • "ensure that recipient payments are closely coordinated with processing schedules, do not impede NASA's ability to efficiently prepare the Orbiters for museum display, and provide sufficient funds in advance of the work to be performed; and"
  • "work closely with the recipient organizations to minimize the possibility of delays in the delivery schedule that could increase the Agency's costs or impact other NASA missions and priorities."


In September 2011, the CEO and two board members of Seattle's Museum of Flight
Museum of Flight
The Museum of Flight is a private non-profit air and space museum at King County International Airport , south of downtown Seattle, Washington. It was established in 1965 and is fully accredited by the American Association of Museums...

 met with NASA Administrator Charles Bolden, pointing out "significant errors in deciding where to put its four retiring space shuttles"; the errors alleged include inaccurate information on Museum of Flight
Museum of Flight
The Museum of Flight is a private non-profit air and space museum at King County International Airport , south of downtown Seattle, Washington. It was established in 1965 and is fully accredited by the American Association of Museums...

's attendance and international visitor statistics, as well as the readiness of the Intrepid Sea-Air-Space Museum
Intrepid Sea-Air-Space Museum
The Intrepid Sea-Air-Space Museum is a military and maritime history museum with a collection of museum ships in New York City. It is located at Pier 86 at 46th Street on the West Side of Manhattan. The museum showcases the World War II aircraft carrier USS Intrepid, the submarine , a Concorde...

's exhibit site.

Space Shuttle successors and legacy


Until another U.S. launch vehicle is ready, crews will travel to and from the International Space Station
International Space Station
The International Space Station is a habitable, artificial satellite in low Earth orbit. The ISS follows the Salyut, Almaz, Cosmos, Skylab, and Mir space stations, as the 11th space station launched, not including the Genesis I and II prototypes...

 aboard Russian Soyuz spacecraft or possibly a future American commercial spacecraft. A planned successor to STS was the "Shuttle II" during the 1980s and 1990s, and later the Constellation program during the 2004–2010 period. CSTS was a proposal to continue to operate STS commercially, after NASA. On September 14, 2011, NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...

 announced that it had selected the design of a new Space Launch System
Space Launch System
The Space Launch System, or SLS, is a Space Shuttle-derived heavy launch vehicle being designed by NASA, following the cancellation of the Constellation Program, to replace the retired Space Shuttle. The NASA Authorization Act of 2010 envisions the transformation of the Ares I and Ares V vehicle...

 that it said would take the agency's astronauts farther into space than ever before and provide the cornerstone for future human space exploration efforts by the U.S.

In culture


Space Shuttles have been featured in numerous works of fiction and nonfiction, from movies for kids to documentaries. Early examples include the 1979 James Bond
James Bond
James Bond, code name 007, is a fictional character created in 1953 by writer Ian Fleming, who featured him in twelve novels and two short story collections. There have been a six other authors who wrote authorised Bond novels or novelizations after Fleming's death in 1964: Kingsley Amis,...

 film, Moonraker
Moonraker (film)
Moonraker is the eleventh spy film in the James Bond series, and the fourth to star Roger Moore as the fictional MI6 agent James Bond. The third and final film in the series to be directed by Lewis Gilbert, it co-stars Lois Chiles, Michael Lonsdale, Corinne Clery, and Richard Kiel...

, where shuttles played a major role well before any were actually launched, Activision
Activision
Activision is an American publisher, majority owned by French conglomerate Vivendi SA. Its current CEO is Robert Kotick. It was founded on October 1, 1979 and was the world's first independent developer and distributor of video games for gaming consoles...

 videogame
Space Shuttle: A Journey into Space (1982) and G. Harry Stine
G. Harry Stine
George Harry Stine was one of the founding figures of model rocketry, a science and technology writer, and a science fiction author.-Education and early career:...

s novel Shuttle Down
Shuttle Down
Shuttle Down is a novel by American author G. Harry Stine, written under the nom de plume Lee Correy. First appearing as a four-part serial in Analog magazine between December 1980 and March 1981, the novel was later published by Ballantyne/Del Rey in 1981, with a second edition following in...

(1981). In the 1986 film SpaceCamp
SpaceCamp
SpaceCamp is a 1986 American film based on a book by Patrick Bailey and Larry B. Williams and inspired by the U.S. Space Camp in Huntsville, Alabama. Directed by Harry Winer from a screenplay by Clifford Green and Casey T. Mitchell, the film stars Kate Capshaw, Kelly Preston, Larry B...

, Atlantis accidentally launched into space with a group of U.S. Space Camp participants as its crew. The 1998 film Armageddon portrayed a combined crew of offshore oil rig workers and US military staff who pilot two modified shuttles to avert the destruction of Earth by an asteroid. Retired American test pilots visited a Russian satellite in the Clint Eastwood
Clint Eastwood
Clinton "Clint" Eastwood, Jr. is an American film actor, director, producer, composer and politician. Eastwood first came to prominence as a supporting cast member in the TV series Rawhide...

 adventure film Space Cowboys
Space Cowboys
Space Cowboys is a 2000 science fiction film directed by Clint Eastwood. Eastwood also stars in the film alongside Tommy Lee Jones, Donald Sutherland, and James Garner as four older "ex-test pilots" who are sent into space to repair an old Soviet satellite...

(2000). This was followed by the 2004 Bollywood movie Swades
Swades
Swades: We, the People is a 2004 Indian film written, produced and directed by Ashutosh Gowariker. The film stars Shahrukh Khan and debutante Gayatri Joshi...

, where a space shuttle was used to launch a special rainfall monitoring satellite. The movie was filmed at Kennedy Space Center in the year following the Columbia disaster that had taken the life of KC Chawla
Kalpana Chawla
Kalpana Chawla was an Indian-American astronaut with NASA. She was one of seven crew members killed in the Space Shuttle Columbia disaster.-Early life:...

, the first woman of Indian origin in space. On television, the 1996 drama The Cape portrayed the lives of a group of NASA astronauts as they prepared for and flew shuttle missions. Odyssey 5
Odyssey 5
Odyssey 5 is a Canadian science fiction series that first ran in 2002 on Showtime in the United States and on Space in Canada.In the United States, the initial run of the series ran for 14 of the 20 episodes, leaving the six remaining episodes unaired for a period of roughly two years...

was a short lived sci-fi series that featured the crew of a space shuttle as the last survivors of a disaster that destroyed Earth.
The Space Shuttle has also been the subject of toys and models; for example, a large Lego
Lego
Lego is a line of construction toys manufactured by the Lego Group, a privately held company based in Billund, Denmark. The company's flagship product, Lego, consists of colorful interlocking plastic bricks and an accompanying array of gears, minifigures and various other parts...

 Space Shuttle model was constructed by visitors at Kennedy Space Center, and smaller models have been sold commercially as a standard "LegoLand" set.

U.S. postage commemorations


The U.S. Postal Service has released several postage issues that depict the Space Shuttle. The first such stamps were issued in 1981, and are on display at the National Postal Museum
National Postal Museum
The National Postal Museum, located opposite Union Station in Washington, D.C., USA, was established through joint agreement between the United States Postal Service and the Smithsonian Institution and opened in 1993. The museum is located across the street from Union Station, in the building that...

.

See also



  • Chrysler SERV
    Chrysler SERV
    SERV, short for Single-stage Earth-orbital Reusable Vehicle, was a proposed space launch system designed by Chrysler's Space Division for the Space Shuttle project. SERV was a single-stage to orbit spacecraft that took off from the existing Saturn V complexes and landed vertically at Kennedy for...

  • Criticism of the Space Shuttle program
    Criticism of the Space Shuttle program
    Criticism of the Space Shuttle program stems from claims that NASA's Shuttle program has failed to achieve its promised cost and utility goals, as well as design, cost, management, and safety issues. More specifically, it has failed in the goal of reducing the cost of space access...

  • Getaway Special
    Getaway Special
    Getaway Special was a NASA program that offered interested individuals, or groups, opportunities to fly small experiments aboard the Space Shuttle...

  • List of human spaceflights
  • List of Space Shuttle crews
  • NASA TV
    NASA TV
    NASA TV is the television service of the United States government agency NASA. NASA TV is broadcast by satellite with a simulcast over the Internet. Local cable television systems across the U.S. and amateur television repeaters may carry NASA TV at their discretion, as NASA-created content is...

    : view live streaming of launch and mission coverage
  • Orbiter Processing Facility
    Orbiter Processing Facility
    An Orbiter Processing Facility was one of three hangars where U.S. space shuttle orbiters underwent maintenance between flights. All three such facilities, OPF-1, OPF-2 and OPF-3, were located at NASA's Kennedy Space Center in Florida at Launch Complex 39.They were located west of the Vehicle...

  • Shuttle-Derived Launch Vehicle
    Shuttle-Derived Launch Vehicle
    Shuttle-Derived Launch Vehicle, or simply Shuttle-Derived Vehicle , is a term describing one of a wide array of concepts that have been developed for creating space launch vehicles from the components, technology and/or infrastructure of the Space Shuttle program. SDVs have also been part of...

  • Shuttle Training Aircraft
    Shuttle Training Aircraft
    The Shuttle Training Aircraft is a NASA training vehicle that duplicates the Space Shuttle's approach profile and handling qualities, allowing Space Shuttle pilots to simulate Shuttle landings under controlled conditions before attempting the task on board the orbiter.-Development:The aircraft's...

  • Space accidents and incidents
  • HL-20 Personnel Launch System
    HL-20 Personnel Launch System
    The HL-20 Personnel Launch System was a circa 1990 NASA spaceplane concept for manned orbital missions studied by NASA's Langley Research Center in Hampton, Virginia. HL-20 was envisaged as a lifting body re-entry vehicle based on the Soviet BOR-4 spaceplane design featuring low operational costs,...


Physics

  • Atmospheric reentry
    Atmospheric reentry
    Atmospheric entry is the movement of human-made or natural objects as they enter the atmosphere of a celestial body from outer space—in the case of Earth from an altitude above the Kármán Line,...

  • Lifting body
    Lifting body
    A lifting body is a fixed-wing aircraft configuration in which the body itself produces lift. In contrast to a flying wing, which is a wing with minimal or no conventional fuselage, a lifting body can be thought of as a fuselage with little or no conventional wing...

  • Reusable launch system
    Reusable launch system
    A reusable launch system is a launch system which is capable of launching a launch vehicle into space more than once. This contrasts with expendable launch systems, where each launch vehicle is launched once and then discarded.No true orbital reusable launch system is currently in use. The...

  • Single-stage-to-orbit
    Single-stage-to-orbit
    A single-stage-to-orbit vehicle reaches orbit from the surface of a body without jettisoning hardware, expending only propellants and fluids. The term usually, but not exclusively, refers to reusable vehicles....



Similar spacecraft

  • Buran program  1974–1992
  • HOTOL
    HOTOL
    HOTOL, for Horizontal Take-Off and Landing, was a British air-breathing space shuttle effort by Rolls Royce and British Aerospace.Designed as a single-stage-to-orbit reusable winged launch vehicle, it was to be fitted with a unique air-breathing engine, the RB545 called the Swallow, to be...

     (cancelled)
  • Comparison of heavy lift launch systems
    Comparison of heavy lift launch systems
    This page exposes the full list of orbital launch systems. For the short simple list of launchers families, see Comparison of orbital launchers families....

  • DIRECT, a shuttle-derived vehicle proposed as an alternative for Constellation program
  • X-20 Dyna-Soar  1957–1963
  • EADS Phoenix
  • Skylon
  • Hermes
    Hermes (shuttle)
    Hermes was a proposed spaceplane designed by the French Centre National d'Études Spatiales in 1975, and later by the European Space Agency. It was superficially similar to the US X-20. France proposed in January 1985 to go through with Hermes development under the auspices of the ESA. Hermes was...

      1975–1992
  • HOPE-X
    HOPE-X
    HOPE was a Japanese experimental spaceplane project designed by a partnership between NASDA and NAL , started in the 1980s. It was positioned for most of its lifetime as one of the main Japanese contributions to the International Space Station, the other being the Japanese Experiment Module...

  • Kliper
    Kliper
    Kliper is a partly reusable manned spacecraft, proposed by RSC Energia.Designed primarily to replace the Soyuz spacecraft, Kliper has been proposed in two versions: as a pure lifting body design and as spaceplane with small wings...

  • Lockheed Martin X-33
    Lockheed Martin X-33
    The Lockheed Martin X-33 was an unmanned, sub-scale technology demonstrator suborbital spaceplane developed in the 1990s under the U.S. government-funded Space Launch Initiative program. The X-33 was a technology demonstrator for the VentureStar orbital spaceplane, which was planned to be a...

      1995–2001
  • Military space shuttle
    Military space shuttle
    A military space shuttle would be the military equivalent of NASA's space shuttle. Many experts believed that it is extremely unlikely that NASA, the United States Department of Defense or any other Federal agency could keep the existence of such a spacecraft secret, given the official knowledge...

  • Orion
    Orion (spacecraft)
    Orion is a spacecraft designed by Lockheed Martin for NASA, the space agency of the United States. Orion development began in 2005 as part of the Constellation program, where Orion would fulfill the function of a Crew Exploration Vehicle....

     (Constellation program)


Further reading


External links




NASA
Non-NASA