The
Space Shuttle, part of the
Space Transportation System (
STS), is a
spacecraftA spacecraft is a craft or machine designed for spaceflight. On a sub-orbital spaceflight, a spacecraft enters space then returns to the Earth. For an orbital spaceflight, a spacecraft enters a closed orbit around the planetary body. Spacecraft used for human spaceflight carry people on board as...
operated by
NASAThe National Aeronautics and Space Administration is an agency of the United States government, responsible for the nation's public space program. NASA was established by the National Aeronautics and Space Act on July 29, 1958, replacing its predecessor, the National Advisory Committee for...
for orbital
human spaceflightHuman spaceflight is spaceflight with a human crew and possibly passengers. This makes it unlike robotic space probes or remotely-controlled satellites...
missions. It began operations in the 1980s and is scheduled to be retired from service in 2010 after 134 launches. Major missions have included launching numerous satellites and interplanetary probes, conducting space science experiments, and servicing and construction of space stations. STS has been used for orbital space missions by NASA, the U.S. Department of Defense, the European Space Agency, and Germany. The United States funded STS development and shuttle operations.
At launch, Space Shuttle consists of a dark orange-colored
external tankA 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 BoostersThe Space Shuttle Solid Rocket Boosters are the pair of large solid rockets used by the space shuttle during the first two minutes of powered flight. Together they provide about 83% of liftoff thrust for the Space Shuttle. They are located on either side of the orange external propellant tank...
(SRBs); and the STS
Orbiter VehicleThe Space Shuttle orbiters are the orbital spacecraft of the Space Shuttle program operated by NASA, the space agency of the United States. Each orbiter is a reusable winged "spaceplane", a mixture of rocket, spacecraft, and aircraft...
(OV) which contains the crew and payload. Payloads can be launched into higher orbits with either of two different booster stages developed for STS (1 stage PAM or 2 stage IUS).
The shuttle stack launches vertically like a conventional rocket from a mobile launch platform. It lifts off under the power of its two solid rocket boosters (SRBs) and its three main engines (SSMEs), the latter fueled by liquid hydrogen and liquid oxygen from the external tank. The space shuttle has a two stage ascent. The boosters are used only for the first stage, while the main engines burn for both stages. About two minutes after liftoff, staging occurs: the SRBs are released, and shortly begin falling into the ocean to be retrieved for reuse. The shuttle orbiter and external tank continue to ascend under power from the three main engines and their inertia. Upon reaching orbit, the main engines are shut down, and the external tank is jettisoned downward and falls to burn up in the atmosphere. However, it is possible for it be re-used in orbit for various applications. At this point, the orbital maneuvering system (OMS) engines may be used to adjust or circularize the achieved orbit.
The orbiter carries
astronautAn astronaut or cosmonaut is a person trained by a human spaceflight program to command, pilot, or serve as a crew member of a spacecraft....
s and payload such as satellites or space station parts into
low earth orbitA 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...
, into the Earth's upper atmosphere or
thermosphereThe thermosphere is 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 upper part of the thermosphere, between...
. Usually, five to seven crew members ride in the orbiter. Two crew members, the Commander and Pilot, are sufficient for a minimal flight, as in the first four "test" flights, STS-1 through STS-4. A typical payload capacity is about , but can be raised depending on the choice of launch configuration. The orbiter carries the payload in a large cargo bay with doors that open along the length of its top, a feature which makes the space shuttle unique among present spacecraft. This feature made possible the deployment of large satellites such as the Hubble Space Telescope, and also to capture and return large payloads back to Earth.
When the orbiter's space mission is complete it fires its
Orbital Maneuvering SystemThe Space Shuttle Orbital Maneuvering System, or OMS , is a system of rocket engines used on the space shuttle orbiter for orbital injection and modifying its orbit. It consists of two "packs" at the back of the Shuttle, the large lumps on either side of the vertical stabilizer...
(OMS) thrusters to drop out of orbit and
re-enterAtmospheric reentry refers to the movement of human-made or natural objects as they enter the atmosphere of a planet from outer space, in the case of Earth from an altitude above the "edge of space." This article primarily addresses the process of controlled reentry of vehicles which are intended...
the lower atmosphere. During the descent, the shuttle orbiter passes through different layers of the atmosphere and decelerates from
hypersonicIn aerodynamics, hypersonic speeds are those that are highly supersonic. Since the 1970s, the term has generally been assumed to refer to speeds of Mach 5 and above...
speed primarily by
aerobrakingAerobraking 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 acts as
gliderGlider 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...
with
reaction control systemA reaction control system, abbreviated RCS, is a subsystem of a spacecraft. Its purpose is attitude control and steering. 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 control...
(RCS) thrusters and fly-by wire controlled hydraulically actuated flight surfaces controlling its descent. It then makes a landing on a long runway as a
spaceplaneA spaceplane is an aircraft designed to pass the edge of space. It combines some of the features of an aircraft and some of a spacecraft. Typically, it takes the form of a spacecraft equipped with wings, and may be airbreathing or be purely rocket based....
. The aerodynamic shape is a compromise between the demands of radically different speeds and air pressures during re-entry, subsonic atmospheric flight, and hypersonic flight. As a result the orbiter has a high sink rate at low altitudes, and transitions from using RCS thrusters in low pressure to flight surfaces at low altitudes.
Description
The Space Shuttle is the first orbital
spacecraftA spacecraft is a craft or machine designed for spaceflight. On a sub-orbital spaceflight, a spacecraft enters space then returns to the Earth. For an orbital spaceflight, a spacecraft enters a closed orbit around the planetary body. Spacecraft used for human spaceflight carry people on board as...
designed for
reusabilityA 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 carries payloads to
low Earth orbitA 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...
, provides crew rotation for the
International Space StationThe International Space Station is an internationally developed research facility currently being assembled in Low Earth Orbit. On-orbit construction of the station began in 1998 and is scheduled to be completed by 2011, with operations continuing until at least 2015...
(ISS), and performs servicing missions. The orbiter can also recover
satelliteIn the context of spaceflight, a satellite is an object which has been placed into orbit by human endeavor. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon....
s and other payloads from orbit and return them to
EarthEarth is the third planet from the Sun. It is the fifth largest of the eight planets in the solar system, and the largest of the terrestrial planets in the Solar System in terms of diameter, mass and density...
. Each Shuttle was designed for a projected lifespan of 100 launches or 10 years' operational life, although this was later extended. The person in charge of designing the STS was
Maxime FagetMaxime "Max" A. Faget was an American engineer. He was the designer of the Mercury capsule, as well as contributing to the later NASA Gemini and Apollo spacecraft and also the Space Shuttle....
, who had also overseen the Mercury, Gemini and Apollo spacecraft designs. The crucial factor in the size and shape of the Shuttle Orbiter was the requirement that it be able to accommodate the largest planned commercial and classified 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 orbitA 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 by developing a spacecraft with reusable components.
Six airworthy Space Shuttle orbiters have been built; the first,
EnterpriseThe 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...
, was not built for orbital space flight, and was used only for testing purposes. Five space-worthy orbiters were built:
ColumbiaSpace 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 flew a total of 27 times before being destroyed during re-entry on February 1, 2003 on the STS-107 mission , killing all seven...
,
ChallengerSpace Shuttle Challenger was NASA's second Space Shuttle orbiter to be put into service, Columbia being the first. Its maiden flight was on April 4, 1983, and it completed nine missions before breaking apart 73 seconds after the launch of its tenth mission, STS-51-L on January 28, 1986, resulting...
,
DiscoverySpace Shuttle Discovery is one of the three currently operational orbiters in the Space Shuttle fleet of NASA, the space agency of the United States. When first flown in 1984, Discovery became the third operational orbiter, and is now the oldest orbiter in service...
,
AtlantisSpace Shuttle Atlantis is one of the three currently operational orbiters in the Space Shuttle fleet of NASA, the space agency of the United States...
, and
EndeavourSpace Shuttle Endeavour is one of three currently operational orbiters in the Space Shuttle fleet of NASA, the space agency of the United States. Endeavour is the fifth and final spaceworthy NASA space shuttle to be built, constructed as a replacement for Challenger...
.
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 disintegratedThe 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, United States, at 11:39...
73 seconds after launch in 1986, and
Endeavour was built as a replacement from structural spare components.
Columbia broke apartThe Space Shuttle Columbia disaster occurred on February 1, 2003, when the Space Shuttle Columbia disintegrated over Texas during re-entry into the Earth's atmosphere, with the loss of all seven crew members, shortly before it was scheduled to conclude its 28th mission, STS-107.The loss of Columbia...
during re-entry in 2003.
Each Space Shuttle is a
reusable launch systemA 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 VehicleThe Space Shuttle orbiters are the orbital spacecraft of the Space Shuttle program operated by NASA, the space agency of the United States. Each orbiter is a reusable winged "spaceplane", a mixture of rocket, spacecraft, and aircraft...
(OV), the
external tankA 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 boostersThe Space Shuttle Solid Rocket Boosters are the pair of large solid rockets used by the space shuttle during the first two minutes of powered flight. Together they provide about 83% of liftoff thrust for the Space Shuttle. They are located on either side of the orange external propellant tank...
(SRBs). The tank and boosters are jettisoned during ascent; only the orbiter enters orbit. The vehicle is launched vertically like a conventional rocket, and the orbiter glides to a horizontal landing, after which it is refurbished for reuse. The SRBs parachute back to earth, where they are collected from the ocean and refilled for another use. Although the external tanks have always been discarded, it is possible to take them into orbit and re-use them (such as for incorporation into a space station).
Roger A. Pielke, Jr. has estimated that the Space Shuttle program 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
GermanyGermany , officially the Federal Republic of Germany , is a country in Central Europe. It is bordered to the north by the North Sea, Denmark, and the Baltic Sea; to the east by Poland and the Czech Republic; to the south by Austria and Switzerland; and to the west by France, Luxembourg, Belgium,...
, Spacelab
D-1STS-61-A was the 22nd Space Shuttle mission. It was a scientific Spacelab mission funded and controlled by West Germany - hence the non-NASA name D-1 . It was also the last successful mission of the Space Shuttle Challenger...
and
D-2STS 55 was the 55th overall flight of the US Space Shuttle and the 14th flight of Columbia. This flight was a multinational Spacelab flight involving 88 experiments from eleven different nations...
(for
Deutschland) with a mission control in
OberpfaffenhofenOberpfaffenhofen 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.
At times, the orbiter itself is referred to as the space shuttle. Technically, this is a slight misnomer, as the actual "Space Transportation System" (space shuttle) is the combination of the orbiter, the external tank, and the two solid rocket boosters. Combined, these are referred to as the "Stack"; the components are assembled in the
Vehicle Assembly BuildingThe Vehicle Assembly Building, or VAB, is located at NASA's Kennedy Space Center. It is the fourth largest building in the world by volume. The building is halfway between Jacksonville and Miami, and due east of Orlando on Merritt Island on the Atlantic coast of Florida...
, which was originally built to assemble the Apollo Saturn V rocket stacks.
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
elevonthumb|right|250px|Elevons at the wing trailing edge are used for pitch and roll control of the [[F-117A Nighthawk]].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...
s, mounted at the trailing edge of the wings, and the
rudderA rudder is a device used to steer a ship, boat, submarine, hovercraft, aircraft,or other conveyance that moves through a fluid . 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, control the orbiter during descent and landing.
The orbiter has a large payload bay measuring comprising most of the
fuselageThe 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...
. 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 engineSpace Shuttle main engines are reusable liquid-fuel rocket engines built by Rocketdyne. Each Space Shuttle ascent to orbit is propelled by three of the fourteen SSME engines currently used by the NASA Space Shuttle program...
s (SSMEs) are mounted on the orbiter's aft fuselage in a triangular pattern. The three engines can swivel 10.5 degrees up and down, and 8.5 degrees from side to side during ascent to change the direction of their thrust and steer the shuttle as well as push. The orbiter structure is made primarily from
aluminumAluminium or aluminum is a silvery white and ductile member of the boron group of chemical elements. It has the symbol Al; its atomic number is 13. It is not soluble in water under normal circumstances....
alloyAn alloy is a partial or complete solid solution of one or more elements in a metallic matrix. Complete solid solution alloys give single solid phase microstructure, while partial solutions give two or more phases that may be homogeneous in distribution depending on thermal history...
, although the engine thrust structure is made primarily from
titaniumTitanium is a chemical element with the symbol Ti and atomic number 22. Sometimes called the “space age metal”, it has a low density and is a strong, lustrous, corrosion-resistant transition metal with a silver color.Titanium can be alloyed with iron, aluminium, vanadium, molybdenum, among other...
alloy.
The orbiter can be used in conjunction with a variety of add-ons depending on the mission. This has included orbital laboratories (
SpacelabSpacelab was a reusable laboratory flown into space on the Space Shuttle. It allowed scientists to perform experiments in microgravity in Earth orbit...
,
SpacehabAstrotech Corporation , formerly Spacehab Inc., is an aerospace company headquartered in Webster, Texas near the Johnson Space Center....
), boosters for launching payloads farther into space (
Inertial Upper StageThe Inertial Upper Stage , originally known as the Interim Upper Stage, is a two-stage solid-fueled booster rocket developed by the U.S. Air Force for the launching of large payloads from either a Titan III rocket or from the payload bay of the Space Shuttle.-Development of the IUS:During the...
,
Payload Assist Modulethumb|SBS-3 satellite with PAM-D stage inside the space shuttlethumb|PAM-D stage in assemblyThe Payload Assist Module is a modular upper stage operated with solid propellant, used with the Space Shuttle, Delta, and Titan launchers. The rocket was used to carry satellites from a low earth orbit to...
), and other add-ons like the
Extended Duration OrbiterThe 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 ModuleA 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 is carried in the cargo bay of a Shuttle and berthed to the Unity or Harmony module on the ISS. From there, supplies are...
s, and Canadarm (RMS).
The space-capable orbiters built are
OV-099 ChallengerSpace Shuttle Challenger was NASA's second Space Shuttle orbiter to be put into service, Columbia being the first. Its maiden flight was on April 4, 1983, and it completed nine missions before breaking apart 73 seconds after the launch of its tenth mission, STS-51-L on January 28, 1986, resulting...
,
OV-102 ColumbiaSpace 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 flew a total of 27 times before being destroyed during re-entry on February 1, 2003 on the STS-107 mission , killing all seven...
,
OV-103 DiscoverySpace Shuttle Discovery is one of the three currently operational orbiters in the Space Shuttle fleet of NASA, the space agency of the United States. When first flown in 1984, Discovery became the third operational orbiter, and is now the oldest orbiter in service...
,
OV-104 AtlantisSpace Shuttle Atlantis is one of the three currently operational orbiters in the Space Shuttle fleet of NASA, the space agency of the United States...
, and
OV-105 EndeavourSpace Shuttle Endeavour is one of three currently operational orbiters in the Space Shuttle fleet of NASA, the space agency of the United States. Endeavour is the fifth and final spaceworthy NASA space shuttle to be built, constructed as a replacement for Challenger...
.
Orbiter add-ons:
Solid Rocket Boosters
Two solid rocket boosters (SRBs) each provide 12.5 million newtons (2.8 million lbf) of thrust at liftoff, which is 83% of the total thrust needed for liftoff. The SRBs are jettisoned two minutes after launch at a height of about , and then deploy parachutes and land in the ocean to be recovered. The SRB cases are made of steel about thick. The Solid Rocket Boosters are re-used many times, for example one of the SRB was launched into space 48 times, including
STS-1STS-1 was the first orbital flight of the Space Shuttle program, launched on April 12, 1981, and returning to Earth April 14. Space Shuttle Columbia orbited the earth 37 times in this 54.5-hour mission...
, during the Shuttle program and is being used in
Ares IAres I is the crew launch vehicle being developed by NASA as a component 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.
Flight systems
Early shuttle missions took along the
GRiD CompassThe Grid Compass was arguably the first laptop computer, when the initial model, the 1101 was introduced in April 1982....
, arguably one of the first
laptopA laptop is a personal computer designed for mobile use and small and light enough to sit on one's lap while in use. A laptop integrates most of the typical components of a desktop computer, including a display, a keyboard, a pointing device , speakers, and often including a battery, into a single...
computers. The Compass sold poorly, as it cost at least
US$The United States dollar is the unit of currency of the United States. The U.S. dollar is normally abbreviated as the dollar sign, $, or as USD or US$ to distinguish it from other dollar-denominated currencies and from others that use the $ symbol. It is divided into 100 cents .The U.S...
8000, but it offered unmatched performance for its weight and size. NASA was one of its main customers.
The shuttle was one of the earliest craft to use a computerized fly-by-wire digital flight control system. This means no mechanical or hydraulic linkages connect the pilot's control stick to the control surfaces or
reaction control systemA reaction control system, abbreviated RCS, is a subsystem of a spacecraft. Its purpose is attitude control and steering. 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 control...
thrusters.
A primary concern with digital fly-by-wire systems is reliability. Much research went into the shuttle computer system. The shuttle uses five identical redundant IBM 32-bit general purpose computers (GPCs), model
AP-101The IBM AP-101 is an avionics computer, used most notably in the U.S. Space Shuttle, but also in the B-52 and F-15, among others. When it was designed, it was a high-performance pipelined processor with core memory. , its specifications are exceeded by many microprocessors...
, constituting a type of
embedded systemAn embedded system is a computer system designed to perform one or a few dedicated functions , often with real-time computing constraints. It is embedded as part of a complete device often including hardware and mechanical parts. In contrast, a general-purpose computer, such as a personal...
. Four computers run specialized software called the Primary Avionics Software System (PASS). A fifth backup computer runs separate software called the Backup Flight System (BFS). Collectively they are called the Data Processing System (DPS).
The design goal of the shuttle's DPS is fail-operational/fail-safe reliability. After a single failure, the shuttle can still continue the mission. After two failures, it can still land safely.
The four general-purpose computers operate essentially in lockstep, checking each other. If one computer fails, the three functioning computers "vote" it out of the system. This isolates it from vehicle control. If a second computer of the three remaining fails, the two functioning computers vote it out. In the rare case of two out of four computers simultaneously failing (a two-two split), one group is picked at random.
The Backup Flight System (BFS) is separately developed software running on the fifth computer, used only if the entire four-computer primary system fails. The BFS was created because although the four primary computers are hardware redundant, they all run the same software, so a generic software problem could crash all of them.
Embedded systemAn embedded system is a computer system designed to perform one or a few dedicated functions , often with real-time computing constraints. It is embedded as part of a complete device often including hardware and mechanical parts. In contrast, a general-purpose computer, such as a personal...
avionicAvionics means "aviation electronics". It comprises electronic systems for use on aircraft, artificial satellites and spacecraft, comprising communications, navigation and the display and management of multiple systems...
software is developed under totally different conditions from public commercial software: the number of code lines is tiny compared to a public commercial software, changes are only made infrequently and with extensive testing, and many programming and test personnel work on the small amount of computer code. However, in theory it can still fail, and the BFS exists for that contingency. While BFS will run in parallel with PASS, to date, BFS has never been engaged to take over control from PASS during any shuttle mission.
The software for the shuttle computers is written in a high-level language called
HAL/SHAL/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/IPL/I is an imperative computer programming language designed for scientific, engineering, and business applications. It has been used by various academic, commercial and industrial users since it was introduced in the early 1960s, and is still actively used .PL/I's principal domain is data...
. It is specifically designed for a
real timeIn computer science, real-time computing , or "reactive computing", is the study of hardware and software systems that are subject to a "real-time constraint"—i.e., operational deadlines from event to system response. By contrast, a non-real-time system is one for which there is no deadline, even...
embedded systemAn embedded system is a computer system designed to perform one or a few dedicated functions , often with real-time computing constraints. It is embedded as part of a complete device often including hardware and mechanical parts. In contrast, a general-purpose computer, such as a personal...
environment.
The IBM AP-101 computers originally had about 424 kilobytes of
magnetic core memoryMagnetic core memory, also known as Forrester memory or ferrite-core memory, is an early form of random access computer memory. It uses small magnetic ceramic rings, the cores, through which wires are threaded to store information via the polarity of the magnetic field they contain...
each. The CPU could process about 400,000 instructions per second. They have 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 has 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.
Markings and insignia
The
typefaceIn typography, a typeface is a set of one or more fonts, in one or more sizes, designed with stylistic unity, each comprising a coordinated set of glyphs. A typeface usually comprises an alphabet of letters, numerals, and punctuation marks; it may also include ideograms and symbols, or consist...
used on the Space Shuttle Orbiter is
HelveticaHelvetica is a widely used sans-serif typeface developed in 1957 by Swiss typeface designer Max Miedinger and Eduard Hoffmann.-History:Helvetica was developed in 1957 by Max Miedinger with Eduard Hoffmann at the Haas'sche Schriftgiesserei of Münchenstein, Switzerland...
. 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 is the
NASA insigniathumb|right|200px|NASA logo thumb|right|200px|NASA sealThe National Aeronautics and Space Administration logo has three official designs, although one of them has been retired from official use since 1992...
, the text 'United States' and a
flag of the United StatesThe 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 of five stars...
. Another United States flag appears on the right wing.
Upgrades
Internally, the shuttle remains 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, similar to those of contemporary airliners like the
Airbus A380The Airbus A380 is a double-deck, wide-body, four-engine airliner manufactured by the European corporation Airbus, a subsidiary of EADS. The largest passenger airliner in the world, the A380 made its maiden flight on 27 April 2005 from Toulouse, France, and made its first commercial flight on 25...
and
Boeing 777The Boeing 777 is a long-range, wide-body twin-engine jet airliner manufactured by Boeing Commercial Airplanes. The world's largest twinjet and commonly referred to as the "Triple Seven", the aircraft can carry between 301 and 368 passengers in a three-class configuration and has a range from...
. This is called a
glass cockpitA glass cockpit is an aircraft cockpit that features electronic instrument displays. Where a traditional cockpit relies on numerous mechanical gauges to display information, a glass cockpit uses several displays driven by flight management systems, that can be adjusted to display flight information...
. Programmable calculators are carried as well (originally the HP-41C). With the coming of the ISS, the orbiter's internal airlocks have been 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 EngineSpace Shuttle main engines are reusable liquid-fuel rocket engines built by Rocketdyne. Each Space Shuttle ascent to orbit is propelled by three of the fourteen SSME engines currently used by the NASA Space Shuttle program...
s (SSMEs) have had several improvements to enhance reliability and power. This explains phrases such as "Main engines throttling up to 104%." This does not mean the engines are being run over a safe limit. The 100% figure is the original specified power level. During the lengthy development program,
RocketdynePratt & Whitney Rocketdyne is a United States company that designs and produces rocket engines that use liquid propellants. Pratt & Whitney Rocketdyne is a division of Pratt & Whitney, itself a wholly owned subsidiary of United Technologies Corporation, headquartered in Canoga Park, California...
determined the engine was capable of safe reliable operation at 104% of the originally specified thrust. They could have rescaled the output number, saying in essence 104% is now 100%. To clarify this would have required revising much previous documentation and software, so the 104% number was retained. SSME upgrades are denoted as "block numbers", such as block I, block II, and block IIA. The upgrades have 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 is 104%, with 106% or 109% used for mission aborts.
For the first two missions,
STS-1STS-1 was the first orbital flight of the Space Shuttle program, launched on April 12, 1981, and returning to Earth April 14. Space Shuttle Columbia orbited the earth 37 times in this 54.5-hour mission...
and
STS-2STS-2 was a space shuttle mission by NASA using the Space Shuttle Columbia, that launched on November 12, 1981 . This was the second space shuttle mission, and was also the second mission for Columbia...
, the
external tankA 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...
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 results 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-91STS-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 June 2, 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 less than the last run of lightweight tanks. As the shuttle cannot fly unmanned, each of these improvements has been "tested" on operational flights.
The SRBs (Solid Rocket Boosters) have undergone improvements as well. Design engineers added a third
O-ringAn 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 joint...
seal to the joints between the segments after the
Space Shuttle Challenger disasterThe 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, United States, at 11:39...
.
Several other SRB improvements were planned in order 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 provides 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-70STS-70 was a Space Shuttle Discovery mission to insert a Tracking and Data Relay Satellite into earth orbit. It was launched from Kennedy Space Center, Florida, on July 13, 1995.-Crew:-Mission parameters:*Mass: 20,159 kg payload...
was delayed in 1995, when
woodpeckerWoodpeckers 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 must be removed prior to launch. The delicate nature of the foam insulation has been the cause of damage to the
Thermal Protection SystemThe Space Shuttle thermal protection system is the barrier that protects the Space Shuttle Orbiter during the searing 1650 °C heat of atmospheric reentry. A secondary goal is to protect from the heat and cold of space while on orbit...
, the tile heat shield and heat wrap of the orbiter, during recent launches. NASA remains confident that this damage, while it was the primary cause of the
Space Shuttle Columbia disasterThe Space Shuttle Columbia disaster occurred on February 1, 2003, when the Space Shuttle Columbia disintegrated over Texas during re-entry into the Earth's atmosphere, with the loss of all seven crew members, shortly before it was scheduled to conclude its 28th mission, STS-107.The loss of Columbia...
on February 1, 2003, will not jeopardize the objective of NASA to complete the
International Space StationThe International Space Station is an internationally developed research facility currently being assembled in Low Earth Orbit. On-orbit construction of the station began in 1998 and is scheduled to be completed by 2011, with operations continuing until at least 2015...
(ISS) in the projected time allotted.
A cargo-only, unmanned variant of the shuttle has been variously proposed, and rejected since the 1980s. It was called the
Shuttle-CThe 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.
On the first four shuttle missions, astronauts wore modified U.S. Air Force high-altitude full-pressure suits, which included a full-pressure helmet during ascent and descent. From the fifth flight,
STS-5STS-5 was a space shuttle mission by NASA using the Space Shuttle Columbia, launched November 11, 1982. This was the fifth space shuttle mission, and was also the fifth mission for the Space Shuttle Columbia.-Crew:-Mission parameters:*Mass:...
, until the loss of
ChallengerThe 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, United States, at 11:39...
, one-piece light blue
nomexNomex 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 SuitThe Advanced Crew Escape Suit, or ACES, is a full pressure suit currently worn by all Space Shuttle crews for the ascent and entry portions of flight. The suit is a direct descendant of the U.S...
(ACES), which resembles the
Gemini space suitThe 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, and has been used since Gemini, in various forms, by the U.S. Air Force and NASA on U-2 and SR-71 Blackbird high-altitude...
worn in the mid-1960s.
To extend the duration that orbiters can stay docked at the ISS, the Station-to-Shuttle Power Transfer System (SSPTS) was installed. The SSPTS allows these orbiters to use power provided by the ISS to preserve their consumables. The SSPTS was first used successfully on
STS-118STS-118 was a space shuttle mission to the International Space Station flown by Space Shuttle Endeavour. STS-118 successfully lifted off on August 8, 2007 from launch pad 39A at Kennedy Space Center , Florida and landed at the Shuttle Landing Facility at KSC on August 21, 2007.It was the first...
.
Technical data
Orbiter specifications (for Endeavour, OV-105)
- Length:
- Wingspan:
- Height:
- Empty weight:
- Gross liftoff weight:
- Maximum landing weight:
- Main engines: Three Rocketdyne Block IIA SSMEs, each with a sea level 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 proportional but opposite force on that system.-Examples:...
of at 104% power
- Maximum payload:
- Payload bay dimensions:
- Operational altitude:
- Speed:
- Crossrange:
- 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 is a military rank which is also sometimes used as a military title depending on the individual customs of a given military service...
, pilotAn aviator is a person who flies aircraft for pleasure or as a profession. The first recorded use of the term was in 1887 as a variation of the French 'aviation', from the latin 'avis', coined 1863 by G. de la Landelle in "Aviation ou Navigation Aérienne"...
, several mission specialistA 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 expirements or technical quests....
s, and rarely a flight engineerIn aviation, a flight engineer is a member of the aircrew of some aircraft. The flight engineer is responsible for monitoring and controlling many of the aircraft systems during flight.- History :...
). On two occasions, eight astronauts have flown (STS-61-ASTS-61-A was the 22nd Space Shuttle mission. It was a scientific Spacelab mission funded and controlled by West Germany - hence the non-NASA name D-1 . It was also the last successful mission of the Space Shuttle Challenger...
, STS-71STS-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 June 27, 1995 from Kennedy Space Center, Florida...
). Eleven people could be accommodated in an emergency mission (see STS-3xxSpace Shuttle missions designated STS-3xx are rescue missions which would be 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:
- Diameter:
- Propellant volume:
- Empty weight:
- Gross liftoff weight:
Solid Rocket Booster specifications
- Length:
- Diameter:
- Empty weight (per booster):
- Gross liftoff weight (per booster):
- Thrust (sea level, liftoff):
System Stack specifications
- Height:
- Gross liftoff weight:
- Total liftoff thrust:
Launch
All Space Shuttle missions are launched from
Kennedy Space CenterThe John F. Kennedy Space Center is the NASA space vehicle launch facility and Launch Control Center on Merritt Island, Brevard County, Florida, United States. The site is near Cape Canaveral, midway between Miami and Jacksonville, Florida. It is long and around wide, covering . A total of...
(KSC). The same
weather criteria used for launchLaunch commit criteria are the measurements obtained during the countdown and launch of a space vehicle which relate to any safety issue and the general success of the launch, as opposed to supplemental data.- Temperature :...
are also for end of mission landing at KSC, and include precipitation (none allowed at the launch pad or flight path), temperatures above 99 °F (37.2 °C) or below 35 °F (1.7 °C), a 20% or greater chance of lightning within 5 nautical miles and cloud cover allows direct visual observation of the shuttle through 8,000 feet. The shuttle will not be launched under conditions where it could be struck by
lightningLightning is an atmospheric discharge of electricity 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
electricityElectricity is a general term that encompasses a variety of phenomena resulting from the presence and flow of electric charge...
of the strike is dissipated through its conductive structure and the aircraft is not electrically
groundedIn 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 is mainly constructed of conductive aluminum, which would normally shield and protect the internal systems. However, upon takeoff the shuttle sends out a long exhaust plume as it ascends, and this plume can trigger lightning by providing a current path to ground. The NASA Anvil Rule for a shuttle launch states that an anvil cloud cannot appear within a distance of 10 nautical miles. The Shuttle Launch Weather Officer will monitor conditions until the final decision to scrub a launch is announced. In addition, the weather conditions must be acceptable at one of the Transatlantic Abort Landing sites (one of several
Space Shuttle abort modesA Space Shuttle abort is 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 safely endure a lightning strike, a similar strike caused problems on Apollo 12, so for safety
NASAThe National Aeronautics and Space Administration is an agency of the United States government, responsible for the nation's public space program. NASA was established by the National Aeronautics and Space Act on July 29, 1958, replacing its predecessor, the National Advisory Committee for...
chooses not to launch the shuttle if lightning is 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 goes through its final preparations for launch, and the countdown is automatically controlled by the Ground Launch Sequencer (GLS), software at the Launch Control Center, which stops the count if it senses a critical problem with any of the Shuttle's on-board systems. The GLS hands 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) begins to drench the
Mobile Launcher PlatformThe 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 either Launch Pad 39-A or 39-B at the Kennedy Space Center as well as serve as the vehicle's launch platform...
(MLP) and SRB trenches with of water to protect the Orbiter from damage by acoustical energy and rocket exhaust reflected from the flame trench and MLP during liftoff.
At T-minus 10 seconds, hydrogen igniters are activated under each engine bell to quell the stagnant gas inside the cones before ignition. Failure to burn these gases can 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 begin charging the combustion chambers with liquid hydrogen and liquid oxygen at this time. The computers reciprocate this action by allowing the redundant computer systems to begin the firing phase.
The three
Space Shuttle Main Engines (SSMEs)Space Shuttle main engines are reusable liquid-fuel rocket engines built by Rocketdyne. Each Space Shuttle ascent to orbit is propelled by three of the fourteen SSME engines currently used by the NASA Space Shuttle program...
start at T minus 6.6 seconds. The main engines ignite sequentially via the shuttle's general purpose computers (GPCs) at 120 millisecond intervals. The GPCs require that the engines reach 90% of their rated performance to complete the final gimbal of the main engine nozzles to liftoff configuration. When the SSMEs start, the water from the sound suppression system flashes into a large volume of steam that shoots southward. All three SSMEs must reach the required 100% thrust within three seconds, otherwise the onboard computers will initiate an RSLS abort. If the onboard computers verify normal thrust buildup, at T minus 0 seconds, the
SRBsThe Space Shuttle Solid Rocket Boosters are the pair of large solid rockets used by the space shuttle during the first two minutes of powered flight. Together they provide about 83% of liftoff thrust for the Space Shuttle. They are located on either side of the orange external propellant tank...
are ignited. At this point the vehicle is committed to takeoff, as the SRBs cannot be turned off once ignited. After the SRBs reach a stable thrust ratio,
pyrotechnic nutsA pyrotechnic fastener is a fastener, usually a nut or bolt, that incorporates a pyrotechnic charge that can be initiated remotely. Explosive charges embedded within the bolts are typically activated by an electric current, and the charge breaks the bolt into two or more pieces...
are detonated by radio controlled signals from the shuttle's GPC's to release the vehicle. The plume from the solid rockets exits 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 GPC's mandate the firing sequences via the Master Events Controller, a computer program integrated with the shuttle's four redundant computer systems. There are extensive emergency procedures (
abort modesA Space Shuttle abort is 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 concern SSME failures, since that is the most complex and highly stressed component. After the
Challenger disasterThe 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, United States, at 11:39...
, there were extensive upgrades to the abort modes.
After the main engines start, but while the solid rocket boosters are still clamped to the pad, the offset thrust from the Shuttle's three main engines causes the entire launch stack (boosters, tank and shuttle) to pitch down about 2 m at cockpit level. This motion is called the "nod", or "twang" in NASA jargon. As the boosters flex back into their original shape, the launch stack pitches slowly back upright. This takes approximately six seconds. At the point when it is perfectly vertical, the boosters ignite and the launch commences.
Shortly after clearing the tower the Shuttle begins a roll and pitch program to set its orbital inclination and so that the vehicle is below the external tank and SRBs, with wings level. The vehicle climbs in a progressively flattening arc, accelerating as the weight of the SRBs and main tank decrease. To achieve low orbit requires much more horizontal than vertical acceleration. This is not visually obvious, since the vehicle rises vertically and is out of sight for most of the horizontal acceleration. The near circular orbital velocity at the altitude of the
International Space StationThe International Space Station is an internationally developed research facility currently being assembled in Low Earth Orbit. On-orbit construction of the station began in 1998 and is scheduled to be completed by 2011, with operations continuing until at least 2015...
is 7.68 kilometers per second , roughly equivalent to Mach 23 at sea level. As the International Space Station orbits at an inclination of 51.6 degrees, the Shuttle has to set its inclination to the same value to rendezvous with the station.
Around a point called
Max QIn aerospace engineering, max Q is the point of maximum dynamic pressure, the point at which aerodynamic stress on a spacecraft in atmospheric flight is maximized....
, where the aerodynamic forces are at their maximum, the main engines are temporarily throttled back to avoid
overspeedingA speed or velocity greater than that for which the aircraft was designed. Depending on conditions, this may be the equivalent of the "never-exceed" speed Vne and could impose major structural damage upon the aircraft if reached or maintained.-See also:...
and hence overstressing the Shuttle, particularly in vulnerable areas such as the wings. At this point, a phenomenon known as the
Prandtl-Glauert singularityThe Prandtl–Glauert singularity or P.G. singularity is sometimes referred to as a vapor cone, shock collar, or shock egg.The point at which a sudden drop in air pressure occurs is generally accepted as the cause of the visible condensation cloud that often surrounds an aircraft traveling at...
occurs, where condensation clouds form during the vehicle's transition to supersonic speed.
126 seconds after launch, explosive bolts release the SRBs and small separation rockets push them laterally away from the vehicle. The SRBs parachute back to the ocean to be reused. The Shuttle then begins accelerating to orbit on the
Space Shuttle main engineSpace Shuttle main engines are reusable liquid-fuel rocket engines built by Rocketdyne. Each Space Shuttle ascent to orbit is propelled by three of the fourteen SSME engines currently used by the NASA Space Shuttle program...
s. The vehicle at that point in the flight has a thrust-to-weight ratio of less than one the main engines actually have insufficient thrust to exceed the force of gravity, and the vertical speed given to it by the SRBs temporarily decreases. However, as the burn continues, the weight of the propellant decreases and the thrust-to-weight ratio exceeds 1 again and the ever-lighter vehicle then continues to accelerate toward orbit.
The vehicle continues to climb and takes on a somewhat nose-up angle to the horizon it uses the main engines to gain and then maintain altitude while it accelerates horizontally towards orbit. At about five and three-quarter minutes into ascent, the orbiter rolls heads up to switch communication links from ground stations to Tracking and Data Relay Satellites.
Finally, in the last tens of seconds of the main engine burn, the mass of the vehicle is low enough that the engines must be throttled back to limit vehicle acceleration to 3 g (30 m/s²), largely for astronaut comfort.
The main engines are shut down before complete depletion of propellant, as running dry would destroy the engines. The oxygen supply is terminated before the hydrogen supply, as the SSMEs react 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 is released by firing explosive bolts and falls, largely burning up in the atmosphere, though some fragments fall into the ocean, in either the
Indian OceanThe Indian Ocean is the third largest of the world's oceanic divisions, covering about 20% of the water on the Earth's surface. It is bounded on the north by South Asia ; on the west by Africa; on the east by Indochina, the Sunda Islands, and Australia; and on the south by the Southern Ocean...
or the
Pacific OceanThe Pacific Ocean is the largest of the Earth's oceanic divisions. Its name is derived from the Latin name Tepre Pacificum, "peaceful sea", bestowed upon it by the Portuguese explorer Ferdinand Magellan. It extends from the Arctic in the north to Antarctica in the south, bounded by Asia and...
depending on launch profile. The sealing action of the tank plumbing and lack of pressure relief systems on the external tank helps it break up in the lower atmosphere. After the foam burns away during reentry, the heat causes a pressure buildup in the remaining liquid oxygen and hydrogen until the tank explodes. This ensures that any pieces that fall back to Earth are small.
To prevent the shuttle from following the external tank back into the lower atmosphere, the
Orbital maneuvering systemThe Space Shuttle Orbital Maneuvering System, or OMS , is a system of rocket engines used on the space shuttle orbiter for orbital injection and modifying its orbit. It consists of two "packs" at the back of the Shuttle, the large lumps on either side of the vertical stabilizer...
(OMS) engines are fired to raise the perigee higher into the upper atmosphere. On some missions (e.g., missions to the ISS), the OMS engines are also used while the main engines are still firing. The reason for putting the orbiter on a path that brings it back to Earth is not just for external tank disposal but also one of safety: if the OMS malfunctions, or the cargo bay doors cannot open for some reason, the shuttle is already on a path to return to earth for an emergency abort landing.
In orbit
Once in orbit, the shuttle does any number of tasks, and usually some combination. In the 1980s and 1990s, many flights involved space sciene missions on the NASA/ESA
SpacelabSpacelab was a reusable laboratory flown into space on the Space Shuttle. It allowed scientists to perform experiments in microgravity in Earth orbit...
, 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 involve staying in orbit several days to two weeks, although longer missions are possible with the
Extended Duration OrbiterThe 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-entryAtmospheric reentry refers to the movement of human-made or natural objects as they enter the atmosphere of a planet from outer space, in the case of Earth from an altitude above the "edge of space." This article primarily addresses the process of controlled reentry of vehicles which are intended...
, except for lowering the landing gear and deploying the air data probes, is normally performed under computer control. However, the re-entry can be flown entirely manually if an emergency arises. The approach and landing phase can be controlled by the autopilot, but is usually hand flown.
The vehicle begins 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 reduces the shuttle's velocity by about . The resultant slowing of the Shuttle lowers its orbital perigee down into the upper atmosphere. The shuttle then flips over, by pushing its nose down (which is actually "up" relative to the Earth, because it's flying upside down). This OMS firing is done roughly halfway around the globe from the landing site.
The vehicle starts encountering more significant air density in the lower thermosphere at about , at around
MachMach number is the speed of an object moving through air, or any fluid substance, divided by the speed of sound as it is in that substance...
25, . The vehicle is controlled by a combination of
RCS thrustersA reaction control system, abbreviated RCS, is a subsystem of a spacecraft. Its purpose is attitude control and steering. 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 control...
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 encounters progressively denser air, it begins 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 performs 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 dissipates speed sideways rather than upwards. This occurs during the 'hottest' phase of re-entry, when the heat-shield glows red and the G-forces are at their highest. By the end of the last turn, the transition to aircraft is almost complete. The vehicle levels its wings, lowers its nose into a shallow dive and begins its approach to the landing site.
The orbiter's maximum glide ratio/
lift-to-drag ratioIn 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
hypersonicIn aerodynamics, hypersonic speeds are those that are 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 . 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.
When the approach and landing phase begins, the orbiter is at a altitude, from the runway. The pilots apply aerodynamic braking to help slow down the vehicle. The orbiter's speed is reduced from , approximately, at touch-down (compared to for a jet airliner). The landing gear is deployed while the Orbiter is flying at . To assist the speed brakes, a drag chute is deployed either after main gear or nose gear touchdown (depending on selected chute deploy mode) at about . The chute is jettisoned once the orbiter slows to .
After landing, the vehicle stands on the runway for several minutes to permit the fumes from poisonous
hydrazineHydrazine is an inorganic chemical compound with the formula N2H4. It is a colourless liquid with an ammonia-like odor and is derived from the same industrial chemistry processes that manufacture ammonia...
(which is used as a fuel for attitude
controlA reaction control system, abbreviated RCS, is a subsystem of a spacecraft. Its purpose is attitude control and steering. 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 control...
, and the orbiter's three
APUsAn auxiliary power unit is a device on a vehicle whose purpose is to provide energy for functions other than propulsion. Different types of APU are found on aircraft, as well as on some large ground vehicles.-Functions of APU:...
) to dissipate, and for the shuttle fuselage to cool before the astronauts disembark.
Landing sites
Space Shuttle landings are always planned for
Kennedy Space CenterThe John F. Kennedy Space Center is the NASA space vehicle launch facility and Launch Control Center on Merritt Island, Brevard County, Florida, United States. The site is near Cape Canaveral, midway between Miami and Jacksonville, Florida. It is long and around wide, covering . A total of...
. If weather conditions make landing there unfavorable, the shuttle can delay its landing until conditions are favorable, touch down at
Edwards Air Force BaseEdwards 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...
,
CaliforniaCalifornia is the most populous state in the United States, and the third largest by area. California is the second most populous sub-national entity in the Americas, behind only São Paulo, Brazil...
, or at other sites around the world. A landing at any site other than Kennedy Space Center means that after touchdown the shuttle must be mated to the
Shuttle Carrier AircraftThe Shuttle Carrier Aircraft are two extensively modified Boeing 747 airliners that NASA uses to transport Space Shuttle orbiters...
and returned to
Cape CanaveralCape Canaveral, from the Spanish Cabo Cañaveral, is a headland in Brevard County, Florida, United States, near the center of that state's Atlantic coast 45 minutes East of Orlando by car. Known as Cape Kennedy from 1963 to 1973, it sits due east of Merritt Island, separated from it by the Banana...
. Space Shuttle Columbia (
STS-3STS-3 was the third space shuttle mission, and was the third mission for the Space Shuttle Columbia. It was the first launch with an unpainted external tank, and the only landing so far at the White Sands Space Harbor near Las Cruces, New Mexico.-Crew:...
) landed at the
White Sands Space HarborWhite 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 MexicoNew Mexico is a state located in the southwestern region of the United States. Inhabited by Native American populations for many centuries, it has also been part of the Imperial Spanish viceroyalty of New Spain, part of Mexico, and a U.S. territory. Among U.S...
; this is viewed as a last resort as NASA scientists believe that the sand could potentially damage the shuttle's exterior.
There are many alternative landing sites that have never been used.
Fleet history
Below is a list of major events in the Space Shuttle orbiter fleet.
Space Shuttle major events
| Date |
Orbiter |
Major event / remarks |
| February 18, 1977 |
EnterpriseThe 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...
|
First flight; Attached to Shuttle Carrier AircraftThe 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 12, 1977 |
Enterprise |
third free flight; First with no tailcone; lakebed landing. |
| October 26, 1977 |
Enterprise |
Final Enterprise free flight; First landing on Edwards AFB concrete runway. |
| April 12, 1981 |
ColumbiaSpace 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 flew a total of 27 times before being destroyed during re-entry on February 1, 2003 on the STS-107 mission , killing all seven...
|
First Columbia flight, first orbital test flight; STS-1STS-1 was the first orbital flight of the Space Shuttle program, launched on April 12, 1981, and returning to Earth April 14. Space Shuttle Columbia orbited the earth 37 times in this 54.5-hour mission...
|
| November 11, 1982 |
Columbia |
First operational flight of the Space Shuttle, first mission to carry four astronauts; STS-5STS-5 was a space shuttle mission by NASA using the Space Shuttle Columbia, launched November 11, 1982. This was the fifth space shuttle mission, and was also the fifth mission for the Space Shuttle Columbia.-Crew:-Mission parameters:*Mass:...
|
| April 4, 1983 |
ChallengerSpace Shuttle Challenger was NASA's second Space Shuttle orbiter to be put into service, Columbia being the first. Its maiden flight was on April 4, 1983, and it completed nine missions before breaking apart 73 seconds after the launch of its tenth mission, STS-51-L on January 28, 1986, resulting...
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First Challenger flight; STS-6STS-6 was a Space Shuttle mission conducted by NASA using Space Shuttle Challenger. Launched April 4, 1983, STS-6 was the sixth space shuttle mission and the first of the ten missions flown on Challenger...
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| August 30, 1984 |
DiscoverySpace Shuttle Discovery is one of the three currently operational orbiters in the Space Shuttle fleet of NASA, the space agency of the United States. When first flown in 1984, Discovery became the third operational orbiter, and is now the oldest orbiter in service...
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First Discovery flight; STS-41-DSTS-41-D was the first space shuttle mission for Space Shuttle Discovery. It was the 12th shuttle mission, and launched from Kennedy Space Center, Florida on August 30, 1984.-Crew:-Mission parameters:*Mass:**Orbiter Liftoff: 119,511 kg...
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| October 3, 1985 |
AtlantisSpace Shuttle Atlantis is one of the three currently operational orbiters in the Space Shuttle fleet of NASA, the space agency of the United States...
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First Atlantis flight; STS-51-JSTS-51-J was a space shuttle mission by NASA that was the first to use the Space Shuttle Atlantis. It was the 21st mission, and carried a payload for the U.S...
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| January 28, 1986 |
Challenger |
Disaster starting 73 seconds after launchThe 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, United States, at 11:39...
; STS-51-LSTS-51-L was the twenty-fifth flight of the American Space Shuttle program, which marked the first time a civilian had flown aboard the Space Shuttle...
; all seven crew members perished. |
| September 29, 1988 |
Discovery |
First post-Challenger mission; STS-26STS-26 was the 26th Space Shuttle mission and the seventh flight for Discovery, launched from Kennedy Space Center, Florida. It was the "Return to Flight" mission, being the first mission after the Space Shuttle Challenger disaster...
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| May 4, 1989 |
Atlantis |
The first Space Shuttle mission to launch a space probe, MagellanThe Magellan spacecraft was a space probe sent to the planet Venus, the first unmanned interplanetary spacecraft to be launched by NASA since its successful Pioneer Orbiter, also to Venus, in 1978...
; STS-30STS-30 was a space shuttle mission by NASA using the Space Shuttle Atlantis. It was the 29th shuttle mission, and the fourth for Atlantis...
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| April 24, 1990 |
Discovery |
Launch of the Hubble Space Telescope The Hubble Space Telescope is a space telescope that was carried into orbit by the space shuttle in April 1990. It is named after the American astronomer Edwin Hubble. Although not the first space telescope, the Hubble is one of the largest and most versatile, and is well-known as both a vital...
; STS-31STS-31 was the thirty-fifth mission of the American Space Shuttle program, which launched the Hubble Space Telescope astronomical observatory into Earth orbit...
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| May 7, 1992 |
EndeavourSpace Shuttle Endeavour is one of three currently operational orbiters in the Space Shuttle fleet of NASA, the space agency of the United States. Endeavour is the fifth and final spaceworthy NASA space shuttle to be built, constructed as a replacement for Challenger...
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First Endeavour flight; STS-49STS-49 was the maiden flight of the Space Shuttle Endeavour. The primary goal of its nine-day mission was to retrieve the Intelsat VI satellite, which failed to leave low earth orbit two years before, attach it to a new upper stage, and relaunch it to its intended geosynchronous orbit...
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| November 19, 1996 |
Columbia |
Longest Shuttle mission to date at 17 days, 15 hours; STS-80 STS-80 was a Space Shuttle mission flown by Space Shuttle Columbia. The launch was originally scheduled for October 31, 1996, but was bumped back to November 19 for several reasons. Likewise, the landing, which was originally scheduled for December 5, was pushed back to December 7 after bad...
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| October 11, 2000 |
Discovery |
100th Space Shuttle mission; STS-92STS-92 was a Space Shuttle mission to the International Space Station flown by Space Shuttle Discovery. STS-92 marked the 100th mission of the Space Shuttle...
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| February 1, 2003 |
Columbia |
Disintegrated during re-entryThe Space Shuttle Columbia disaster occurred on February 1, 2003, when the Space Shuttle Columbia disintegrated over Texas during re-entry into the Earth's atmosphere, with the loss of all seven crew members, shortly before it was scheduled to conclude its 28th mission, STS-107.The loss of Columbia...
; STS-107STS-107 was a space shuttle mission by NASA using the Space Shuttle Columbia, launched January 16, 2003. This was a multi-disciplinary microgravity and Earth science research mission with a multitude of international scientific investigations conducted continuously during 16 days in orbit.The...
; all seven crew members perished. |
| July 25, 2005 |
Discovery |
First post-Columbia mission; STS-114STS-114 was the first "Return to Flight" Space Shuttle mission following the Space Shuttle Columbia disaster. The Space Shuttle Discovery launched at 10:39 a.m. EDT , July 26, 2005. The launch, 907 days STS-114 was the first "Return to Flight" Space Shuttle mission following the Space Shuttle...
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| August 28, 2009 |
Discovery |
Carried 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 is carried in the cargo bay of a Shuttle and berthed to the Unity or Harmony module on the ISS. From there, supplies are...
(MPLM) Leonardo to ISS; STS-128STS-128 was the most recent space shuttle mission to the International Space Station . It used , and launched on August 28, 2009. The primary payload was the Multi-Purpose Logistics Module Leonardo, containing a collection of experiments for studying the physics and chemistry of microgravity...
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| Planned fleet events |
| 2010 |
Atlantis |
Last planned Atlantis flight; STS-132 STS-132 is a scheduled mission of to visit the International Space Station, targeted for May 14, 2010.The primary payload is scheduled to be the Russian Rassvet Mini-Research Module along with an Integrated Cargo Carrier-Vertical Light Deployable containing a radiator, airlock and a spare elbow...
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| 2010 |
Discovery |
Last planned Discovery STS-133 STS-133 is a mission of the to visit the International Space Station, targeted for launch September 16, 2010. The mission will transport the Permanent Logistics Module and the fourth ExPRESS Logistics Carrier to the ISS...
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| 2010 |
Endeavour |
Last planned Endeavour flight; last planned flight of the space shuttle program; STS-134 STS-134 is a mission of the to visit the International Space Station, targeted for launch July 29, 2010. This flight will deliver the Alpha Magnetic Spectrometer and the third ExPRESS Logistics Carrier to the International Space Station.The mission will mark the final flight of Endeavour, and...
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Sources: NASA launch manifest, NASA Space Shuttle archive
Shuttle disasters
On January 28, 1986, the Space Shuttle Challenger disintegrated 73 seconds after launch due to the failure of the the right SRB, killing all seven astronauts on board. The disaster was caused by cold-temperature impairment of the SRB O-rings, a mission critical component. Repeated warnings from design engineers voicing concerns about the lack of evidence of the O-ring's safety when the temperature was below 53 °F (11.7 °C) were ignored by NASA managers.
In 2003, the Space Shuttle Columbia disintegrated during re-entry because of damage to heat tiles caused during launch. Ground control engineers made three separate requests for high-resolution images taken by the Department of Defense that would have provided a clearer understanding of the extent of the damage, while NASA's chief thermal protection system (TPS) engineer requested that astronauts on board the Columbia be allowed to leave the vehicle to inspect the damaged tiles. 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 the Space Shuttle Atlantis were not considered by NASA management at the time.
Retirement
NASA's current plans call for the Space Shuttle to be retired from service in 2010, after nearly 30 years of service. Atlantis will be the first of NASA's three remaining operational space shuttles to be retired as the program winds down. To fill the void left by the Shuttle's retirement, a new spacecraft is being developed to ferry not only passengers and cargo to the
ISSISS generally refers to the International Space Station, but may also refer to:* Injury Severity Score, an established medical score used to asses the severity of trauma* ISS A/S, a Danish service company...
but also to travel beyond Earth orbit to the
MoonThe Moon is Earth's only natural satellite and the fifth largest satellite in the Solar System. The average centre-to-centre distance from the Earth to the Moon is , about thirty times the diameter of the Earth. The common centre of mass of the system is located at about —a quarter the Earth's...
and
MarsMars is the fourth planet from the Sun in the Solar System. The planet is named after Mars, the Roman god of war. It is also referred to as the "Red Planet" because of its reddish appearance, due to iron oxide prevalent on its surface....
. Originally called the
Crew Exploration VehicleThe Crew Exploration Vehicle was the conceptual component of the Vision for Space Exploration that later became known as the Orion spacecraft. The concept for the vehicle was officially announced in a speech given by George W...
, the concept has evolved into the
OrionOrion is a spacecraft design currently under development by the United States space agency NASA. Each Orion spacecraft will carry a crew of four to six astronauts. The spacecraft is designed to be launched by the Ares I, a launch vehicle, also currently under development...
spacecraft and the project has been dubbed
Project ConstellationConstellation is a human spaceflight program within NASA, the space agency of the United States. The stated goals of the program are gaining significant experience in operating away from Earth's environment, developing technologies needed for opening the space frontier and conducting fundamental...
. This next-generation vehicle is targeted for first manned launch in 2014 at the earliest. Therefore, all crews traveling to and from the
International Space StationThe International Space Station is an internationally developed research facility currently being assembled in Low Earth Orbit. On-orbit construction of the station began in 1998 and is scheduled to be completed by 2011, with operations continuing until at least 2015...
during the intervening period will have to do so on board Russian spacecraft or possibly an American commercial spacecraft (see below).
Congress is discussing the possibility of delaying the retirement of the space shuttles. One proposal, which would cost about $10 billion, would have the shuttles make six or seven additional flights between 2010 and 2013 and would accelerate development of the Orion ships to be ready by then. A second proposal would keep the shuttles flying until 2015 and leave intact Orion's schedule.
Commercial replacement vehicles and services
NASA announced the awarding of contracts for the
cargo resupplyCommercial Orbital Transportation Services is a NASA program to coordinate the commercial delivery of crew and cargo to the International Space Station. The program was announced on January 18, 2006...
of the International Space Station (ISS) to
SpaceXSpace Exploration Technologies Corporation is an American space transport company founded by PayPal co-founder Elon Musk. It has developed the Falcon 1 and is developing the Falcon 9, both of which are partially reusable launch vehicles. SpaceX is also developing the Dragon series of spacecraft to...
and
Orbital Sciences CorporationOrbital Sciences Corporation is a company which specializes in satellite launch and manufacture. Its Launch Systems Group is heavily involved with missile defense launch systems. Orbital formerly owned ORBIMAGE and the Magellan line of GPS receivers, though they are now divested...
on December 23, 2008. SpaceX will use its
Falcon 9The Falcon 9 is a reusable two-stage-to-orbit, liquid oxygen and rocket-grade kerosene powered launch vehicle manufactured by SpaceX. It is scheduled to have its maiden launch in 2009...
launch vehicle and Dragon spacecraft. Orbital Sciences will use its
Taurus IITaurus II is an US medium-capacity expendable launch system being developed by Orbital Sciences Corporation. NASA awarded to Orbital a Commercial Orbital Transportation Services contract to launch cargo missions to the International Space Station. Under this contract, the Taurus II will be used to...
launch vehicle and
Cygnus spacecraftThe Cygnus spacecraft is an unmanned resupply spacecraft being developed by Orbital Sciences Corporation as part of NASA's COTS project. They are designed to transport supplies to the International Space Station after the retirement of the Space Shuttle...
.
See also
- Criticism of the Space Shuttle program
Criticism of the Space Shuttle program stems from claims that the 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. Space shuttle...
- Getaway Special
Getaway Special was a NASA program that offered interested individuals or groups, opportunities to fly small experiments aboard the Space Shuttle...
- GRiD Compass
The Grid Compass was arguably the first laptop computer, when the initial model, the 1101 was introduced in April 1982....
the early laptop carried aboard the shuttle.
- Human spaceflight
Human spaceflight is spaceflight with a human crew and possibly passengers. This makes it unlike robotic space probes or remotely-controlled satellites...
- List of human spaceflights
- List of space shuttle missions
- Space Shuttle design process
- Orbiter Processing Facility
A NASA Orbiter Processing Facility is one of three hangars where space shuttle orbiters undergo maintenance between flights.- Processing flow :When a shuttle mission is completed, the orbiter is parked in its OPF...
- Shuttle Derived Launch Vehicle
- Shuttle SERV
- 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
- Space exploration
Space exploration is the use of astronomy and space technology to explore outer space. Physical exploration of space is conducted both by human spaceflights and by robotic spacecraft....
- Space Shuttle abort modes
A Space Shuttle abort is 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...
- Space Shuttle crews
This is a list of persons who served aboard Space Shuttle crews, arranged in chronological order by mission.Abbreviations:* PC = Payload Commander* MSE = USAF Manned Spaceflight Engineer...
- Space Shuttle program
NASA's Space Shuttle, officially called Space Transportation System , is the United States government's current manned launch vehicle. The winged Space Shuttle orbiter is launched vertically, usually carrying five to seven astronauts and up to 50,000 lb of payload into low earth orbit...
- HL-20 Personnel Launch System
The HL-20 Personnel Launch System was a NASA concept studied by NASA's Langley Research Center in Hampton, Virginia, based on an enhanced lifting body candidate for manned orbital missions...
Physics
- Atmospheric reentry
Atmospheric reentry refers to the movement of human-made or natural objects as they enter the atmosphere of a planet from outer space, in the case of Earth from an altitude above the "edge of space." This article primarily addresses the process of controlled reentry of vehicles which are intended...
- Lifting body
The lifting body is an aircraft configuration where the body itself produces lift. It is related to flying wing which is a wing without a conventional fuselage. A lifting body is a fuselage that generates lift without the shape of a typical thin and flat wing structure. A flying wing seeks to...
- 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
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
- Comparison of heavy lift launch systems
When comparing launch systems, those capable of lifting the most mass to orbit use Heavy Lift Launch Vehicles. The phrase "heavy lift" has often been applied to vehicles like Saturn V, Titan IV, Ariane 5, Proton, and Delta IV-Heavy...
- DIRECT
DIRECT is a proposed alternative Shuttle-Derived Launch Vehicle architecture supporting NASA's Vision for Space Exploration, which would replace the space agency's planned Ares I and Ares V rockets with another family of launch vehicles named "Jupiter"....
, a shuttle-derived vehicle proposed as an alternative for Project ConstellationConstellation is a human spaceflight program within NASA, the space agency of the United States. The stated goals of the program are gaining significant experience in operating away from Earth's environment, developing technologies needed for opening the space frontier and conducting fundamental...
- X-20 Dyna-Soar 1957-1963
- EADS Phoenix
- Hermes
Hermes was a proposed spaceplane designed by the French Centre national d'études spatiales in 1975, and later by the European Space Agency, which was superficially similar to the US X-20. France proposed in January 1985 to go through with Hermes development under the auspices of ESA. Hermes was to...
1975-1992
- 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 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
The Lockheed Martin X-33 was an unmanned, sub-scale technology demonstrator for the VentureStar under the Space Launch Initiative. The VentureStar was planned to be a next-generation, commercially operated reusable launch vehicle...
1995-2001
- Military space shuttle
A military space shuttle would have been the military equivalent of NASA's space shuttle. Many experts believe 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...
- Orion
Orion is a spacecraft design currently under development by the United States space agency NASA. Each Orion spacecraft will carry a crew of four to six astronauts. The spacecraft is designed to be launched by the Ares I, a launch vehicle, also currently under development...
(Project ConstellationConstellation is a human spaceflight program within NASA, the space agency of the United States. The stated goals of the program are gaining significant experience in operating away from Earth's environment, developing technologies needed for opening the space frontier and conducting fundamental...
)
Further reading
External links