157-571: STS-400 was the Space Shuttle contingency support (Launch On Need) flight that would have been launched using Space Shuttle Endeavour if a major problem occurred on Space Shuttle Atlantis during STS-125 , the final Hubble Space Telescope servicing mission (HST SM-4). Due to the much lower orbital inclination of the HST compared to the ISS, the shuttle crew would have been unable to use
314-419: A nose cone . The nose cone consists of a removable conical assembly that serves as an aerodynamic fairing for the propulsion and electrical system components. The foremost element of the nose cone functions as a cast aluminium lightning rod. The LOX tank volume is 19,744 cu ft (559.1 m ) at 22 psi (150 kPa) and −297 °F (90.4 K; −182.8 °C) ( cryogenic ). The tank feeds into
471-993: A spaceplane to a runway landing, usually to the Shuttle Landing Facility at KSC, Florida, or to Rogers Dry Lake in Edwards Air Force Base , California. If the landing occurred at Edwards, the orbiter was flown back to the KSC atop the Shuttle Carrier Aircraft (SCA), a specially modified Boeing 747 designed to carry the shuttle above it. The first orbiter, Enterprise , was built in 1976 and used in Approach and Landing Tests (ALT), but had no orbital capability. Four fully operational orbiters were initially built: Columbia , Challenger , Discovery , and Atlantis . Of these, two were lost in mission accidents: Challenger in 1986 and Columbia in 2003 , with
628-569: A 17 in (430 mm) diameter feed line that conveys the liquid oxygen through the intertank, then outside the ET to the aft right-hand ET/orbiter disconnect umbilical. The 17 in (430 mm) diameter feed line permits liquid oxygen to flow at approximately 2,787 lb/s (75,800 kg/min) with the RS-25s operating at 104% or permits a maximum flow of 17,592 US gal/min (1.1099 m /s). All loads except aerodynamic loads are transferred from
785-487: A NASA engineer who had worked to design the Mercury capsule, patented a design for a two-stage fully recoverable system with a straight-winged orbiter mounted on a larger straight-winged booster. The Air Force Flight Dynamics Laboratory argued that a straight-wing design would not be able to withstand the high thermal and aerodynamic stresses during reentry, and would not provide the required cross-range capability. Additionally,
942-497: A crewed spaceflight engineer on both STS-51-C and STS-51-J to serve as a military representative for a National Reconnaissance Office payload. A Space Shuttle crew typically had seven astronauts, with STS-61-A flying with eight. The crew compartment comprised three decks and was the pressurized, habitable area on all Space Shuttle missions. The flight deck consisted of two seats for the commander and pilot, as well as an additional two to four seats for crew members. The mid-deck
1099-459: A future reusable shuttle: Class I would have a reusable orbiter mounted on expendable boosters, Class II would use multiple expendable rocket engines and a single propellant tank (stage-and-a-half), and Class III would have both a reusable orbiter and a reusable booster. In September 1969, the Space Task Group, under the leadership of U.S. Vice President Spiro Agnew , issued a report calling for
1256-576: A glider. Its three-part fuselage provided support for the crew compartment, cargo bay, flight surfaces, and engines. The rear of the orbiter contained the Space Shuttle Main Engines (SSME), which provided thrust during launch, as well as the Orbital Maneuvering System (OMS), which allowed the orbiter to achieve, alter, and exit its orbit once in space. Its double- delta wings were 18 m (60 ft) long, and were swept 81° at
1413-477: A mobile platform for astronauts conducting an EVA. The RMS was built by the Canadian company Spar Aerospace and was controlled by an astronaut inside the orbiter's flight deck using their windows and closed-circuit television. The RMS allowed for six degrees of freedom and had six joints located at three points along the arm. The original RMS could deploy or retrieve payloads up to 29,000 kg (65,000 lb), which
1570-528: A partial-pressure version of the high-altitude pressure suits with a helmet. In 1994, the LES was replaced by the full-pressure Advanced Crew Escape Suit (ACES), which improved the safety of the astronauts in an emergency situation. Columbia originally had modified SR-71 zero-zero ejection seats installed for the ALT and first four missions, but these were disabled after STS-4 and removed after STS-9 . The flight deck
1727-517: A partially reusable system would be the most cost-effective solution. The head of the NASA Office of Manned Space Flight, George Mueller , announced the plan for a reusable shuttle on August 10, 1968. NASA issued a request for proposal (RFP) for designs of the Integral Launch and Reentry Vehicle (ILRV) on October 30, 1968. Rather than award a contract based upon initial proposals, NASA announced
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#17328554980351884-541: A phased approach for the Space Shuttle contracting and development; Phase A was a request for studies completed by competing aerospace companies, Phase B was a competition between two contractors for a specific contract, Phase C involved designing the details of the spacecraft components, and Phase D was the production of the spacecraft. In December 1968, NASA created the Space Shuttle Task Group to determine
2041-445: A piece of foam (and/or ice) about 3.9 in (100 mm) in diameter separated from a feedline attachment bracket on the tank, ricocheted off one of the aft struts and struck the underside of the wing, damaging two tiles. The damage was not considered dangerous. The external hardware, ET–orbiter attachment fittings, umbilical fittings, and electrical and range safety system weigh 9,100 pounds (4,100 kg). Each propellant tank has
2198-481: A port-side hatch that the crew used for entry and exit while on Earth. The airlock is a structure installed to allow movement between two spaces with different gas components, conditions, or pressures. Continuing on the mid-deck structure, each orbiter was originally installed with an internal airlock in the mid-deck. The internal airlock was installed as an external airlock in the payload bay on Discovery , Atlantis , and Endeavour to improve docking with Mir and
2355-665: A result of an O-ring failing at low temperature, the SRBs were redesigned to provide a constant seal regardless of the ambient temperature. The Space Shuttle's operations were supported by vehicles and infrastructure that facilitated its transportation, construction, and crew access. The crawler-transporters carried the MLP and the Space Shuttle from the VAB to the launch site. The Shuttle Carrier Aircraft (SCA) were two modified Boeing 747s that could carry an orbiter on its back. The original SCA (N905NA)
2512-661: A second orbiter. Later that month, Rockwell began converting STA-099 to OV-099, later named Challenger . On January 29, 1979, NASA ordered two additional orbiters, OV-103 and OV-104, which were named Discovery and Atlantis . Construction of OV-105, later named Endeavour , began in February 1982, but NASA decided to limit the Space Shuttle fleet to four orbiters in 1983. After the loss of Challenger , NASA resumed production of Endeavour in September 1987. After it arrived at Edwards AFB, Enterprise underwent flight testing with
2669-645: A separate central processing unit (CPU) and input/output processor (IOP), and non-volatile solid-state memory . From 1991 to 1993, the orbiter vehicles were upgraded to the AP-101S, which improved the memory and processing capabilities, and reduced the volume and weight of the computers by combining the CPU and IOP into a single unit. Four of the GPCs were loaded with the Primary Avionics Software System (PASS), which
2826-414: A separate, pyrotechnically operated, propulsive tumble vent valve at its forward end. At separation, the liquid oxygen tumble vent valve was opened, providing impulse to assist in the separation maneuver and more positive control of the entry aerodynamics of the ET. The last flight with the tumble valve active was STS-36. Each of the two aft external tank umbilical plates mate with a corresponding plate on
2983-410: A speech. After STS-4, NASA declared its Space Transportation System (STS) operational. The Space Shuttle was the first operational orbital spacecraft designed for reuse . Each Space Shuttle orbiter was designed for a projected lifespan of 100 launches or ten years of operational life, although this was later extended. At launch, it consisted of the orbiter , which contained the crew and payload,
3140-409: A tanking test determined the cause of the errors to be a fault in a wiring connector, rather than a failure of the sensors themselves. Four pressure transducers located at the top of the liquid oxygen and liquid hydrogen tanks monitor the ullage pressures. The ET also has two electrical umbilicals that carry electrical power from the orbiter to the tank and the two SRBs and provide information from
3297-761: A total of 135 missions from 1981 to 2011. They launched from the Kennedy Space Center (KSC) in Florida . Operational missions launched numerous satellites , interplanetary probes , and the Hubble Space Telescope (HST), conducted science experiments in orbit, participated in the Shuttle- Mir program with Russia, and participated in the construction and servicing of the International Space Station (ISS). The Space Shuttle fleet's total mission time
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#17328554980353454-459: A total of 14 astronauts killed. A fifth operational (and sixth in total) orbiter, Endeavour , was built in 1991 to replace Challenger . The three surviving operational vehicles were retired from service following Atlantis ' s final flight on July 21, 2011. The U.S. relied on the Russian Soyuz spacecraft to transport astronauts to the ISS from the last Shuttle flight until the launch of
3611-428: A two-part drag parachute system to slow the orbiter after landing. The orbiter used retractable landing gear with a nose landing gear and two main landing gear, each containing two tires. The main landing gear contained two brake assemblies each, and the nose landing gear contained an electro-hydraulic steering mechanism. The Space Shuttle crew varied per mission. They underwent rigorous testing and training to meet
3768-420: A vent and relief valve at its forward end. This dual-function valve can be opened by ground support equipment for the vent function during prelaunch and can open during flight when the ullage (empty space) pressure of the liquid hydrogen tank reaches 38 psi (260 kPa) or the ullage pressure of the liquid oxygen tank reaches 25 psi (170 kPa). On early flights, the liquid oxygen tank contained
3925-628: Is a retired, partially reusable low Earth orbital spacecraft system operated from 1981 to 2011 by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program . Its official program name was Space Transportation System (STS), taken from the 1969 plan led by U.S. Vice President Spiro Agnew for a system of reusable spacecraft where it was the only item funded for development. The first ( STS-1 ) of four orbital test flights occurred in 1981, leading to operational flights ( STS-5 ) beginning in 1982. Five complete Space Shuttle orbiter vehicles were built and flown on
4082-456: Is an Al-Li alloy designed by Lockheed Martin and Reynolds for storage of cryogenics (and used for the SLW version of the ET - earlier versions used Al 2219 ). Al 2090 is a commercially available Al-Li alloy. The LOX tank is located at the top of the ET and has an ogive shape to reduce aerodynamic drag and aerothermodynamic heating. The ogive nose section is capped by a flat removable cover plate and
4239-452: Is cooled by 1,080 interior lines carrying liquid hydrogen and is thermally protected by insulative and ablative material. The RS-25 engines had several improvements to enhance reliability and power. During the development program, Rocketdyne determined that the engine was capable of safe reliable operation at 104% of the originally specified thrust. To keep the engine thrust values consistent with previous documentation and software, NASA kept
4396-468: Is vented through umbilical connections over a large diameter pipe on an arm extended from the fixed service structure. The connection for this pipe between the ET and service structure is made at the ground umbilical carrier plate (GUCP). Sensors are also installed at the GUCP to measure hydrogen levels. Countdowns of STS-80 , STS-119 , STS-127 and STS-133 have been halted and resulted in several week delays in
4553-508: The Columbia disaster . Beginning with STS-114 , the orbiter vehicles were equipped with the wing leading edge impact detection system to alert the crew to any potential damage. The entire underside of the orbiter vehicle, as well as the other hottest surfaces, were protected with tiles of high-temperature reusable surface insulation, made of borosilicate glass -coated silica fibers that trapped heat in air pockets and redirected it out. Areas on
4710-473: The Atlas V and Delta IV pads, to protect the newer, taller Ares I rocket from lightning strikes. As a contingency mission, STS-400 was not given official support by NASA for the production of a crew patch or emblem. However artwork was created for use by the mission team as an unofficial emblem by Mike Okuda , who also illustrated the official patch of STS-125. As described by Paul F. Dye, Lead Flight Director of
4867-492: The Clean Air Act . In its place, a hydrochlorofluorocarbon known as HCFC-141b was certified for use and phased into the shuttle program. Remaining foams, particularly detail pieces sprayed by hand, continued to use CFC-11 through the end of the program. These areas include the problematic bipod and PAL ramps, as well as some fittings and interfaces. For the bipod ramp in particular, "the process of applying foam to that part of
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5024-749: The Crew Dragon Demo-2 mission in May 2020. In the late 1930s, the German government launched the " Amerikabomber " project, and Eugen Sanger 's idea, together with mathematician Irene Bredt , was a winged rocket called the Silbervogel (German for "silver bird"). During the 1950s, the United States Air Force proposed using a reusable piloted glider to perform military operations such as reconnaissance, satellite attack, and air-to-ground weapons employment. In
5181-558: The ISS , along with the Orbiter Docking System . The airlock module can be fitted in the mid-bay, or connected to it but in the payload bay. With an internal cylindrical volume of 1.60 metres (5 feet 3 inches) diameter and 2.11 metres (6 feet 11 inches) in length, it can hold two suited astronauts. It has two D-shaped hatchways 1.02 m (40 in) long (diameter), and 0.91 m (36 in) wide. The orbiter
5338-591: The Indian Ocean (or Pacific Ocean in the case of direct-insertion launch trajectories), away from shipping lanes and were not recovered. The ET was the largest element of the Space Shuttle, and when loaded, it was also the heaviest. It consisted of three major components: The ET was the "backbone" of the shuttle during launch, providing structural support for attachment with the Space Shuttle Solid Rocket Boosters (SRBs) and orbiter. The tank
5495-419: The International Space Station as a "safe haven", and NASA would not have been able to follow the usual plan of recovering the crew with another shuttle at a later date. Instead, NASA developed a plan to conduct a shuttle-to-shuttle rescue mission, similar to proposed rescue missions for pre-ISS flights . The rescue mission would have been launched only three days after call-up and as early as seven days after
5652-592: The Martin Marietta X-24B . The program tested aerodynamic characteristics that would later be incorporated in design of the Space Shuttle, including unpowered landing from a high altitude and speed. On September 24, 1966, as the Apollo space program neared its design completion, NASA and the Air Force released a joint study concluding that a new vehicle was required to satisfy their respective future demands and that
5809-543: The Shuttle Carrier Aircraft , a Boeing 747 that had been modified to carry the orbiter. In February 1977, Enterprise began the Approach and Landing Tests (ALT) and underwent captive flights, where it remained attached to the Shuttle Carrier Aircraft for the duration of the flight. On August 12, 1977, Enterprise conducted its first glide test, where it detached from the Shuttle Carrier Aircraft and landed at Edwards AFB. After four additional flights, Enterprise
5966-569: The Space Shuttle launch vehicle that contained the liquid hydrogen fuel and liquid oxygen oxidizer . During lift-off and ascent it supplied the fuel and oxidizer under pressure to the three RS-25 main engines in the orbiter . The ET was jettisoned just over 10 seconds after main engine cut-off (MECO) and it re-entered the Earth's atmosphere. Unlike the Solid Rocket Boosters , external tanks were not re-used. They broke up before impact in
6123-619: The Tracking and Data Relay Satellite System and the Spacecraft Tracking and Data Acquisition Network ground stations to communicate with the orbiter throughout its orbit. Additionally, the orbiter deployed a high-bandwidth K u band radio out of the cargo bay, which could also be utilized as a rendezvous radar. The orbiter was also equipped with two UHF radios for communications with air traffic control and astronauts conducting EVA. The Space Shuttle's fly-by-wire control system
6280-553: The VAB . Initially, STS-125 was retargeted for no earlier than February 2009. This changed the STS-400 vehicle from Endeavour to Discovery . The mission was redesignated STS-401 due to the swap from Endeavour to Discovery . STS-125 was then delayed further, allowing Discovery mission STS-119 to fly beforehand. This resulted in the rescue mission reverting to Endeavour , and the STS-400 designation being reinstated. In January, 2009, it
6437-529: The external tank (ET), and the two solid rocket boosters (SRBs). Responsibility for the Space Shuttle components was spread among multiple NASA field centers. The KSC was responsible for launch, landing, and turnaround operations for equatorial orbits (the only orbit profile actually used in the program). The U.S. Air Force at the Vandenberg Air Force Base was responsible for launch, landing, and turnaround operations for polar orbits (though this
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6594-484: The qualification requirements for their roles. The crew was divided into three categories: Pilots, Mission Specialists, and Payload Specialists. Pilots were further divided into two roles: Space Shuttle Commanders and Space Shuttle Pilots. The test flights only had two members each, the commander and pilot, who were both qualified pilots that could fly and land the orbiter. The on-orbit operations, such as experiments, payload deployment, and EVAs, were conducted primarily by
6751-416: The solid rocket boosters (SRB) began on 11 July 2008. One month later, the external tank arrived at KSC and was mated with the SRBs on 29 August 2008. Endeavour joined the stack on 12 September 2008 and was rolled out to Pad 39B one week later. Since STS-126 launched before STS-125, Atlantis was rolled back to the VAB on 20 October, and Endeavour rolled around to Launch Pad 39A on 23 October. When it
6908-445: The 2195 aluminum-lithium alloy, which was 40% stronger and 10% less dense than its predecessor, 2219 aluminum-lithium alloy. The SLWT weighed 3,400 kg (7,500 lb) less than the LWT, which allowed the Space Shuttle to deliver heavy elements to ISS's high inclination orbit. The Solid Rocket Boosters (SRB) provided 71.4% of the Space Shuttle's thrust during liftoff and ascent, and were
7065-452: The Air Force required a larger payload capacity than Faget's design allowed. In January 1971, NASA and Air Force leadership decided that a reusable delta-wing orbiter mounted on an expendable propellant tank would be the optimal design for the Space Shuttle. After they established the need for a reusable, heavy-lift spacecraft, NASA and the Air Force determined the design requirements of their respective services. The Air Force expected to use
7222-558: The ET remain unchanged. The last SWT, flown on STS-7 , weighed approximately 77,000 pounds (35,000 kg) inert. Beginning with the STS-6 mission, a lightweight ET (LWT), was introduced. This tank was used for the majority of the Shuttle flights, and was last used during the launch of the ill-fated STS-107 mission. Although tanks vary slightly in weight, each weighed approximately 66,000 pounds (30,000 kg) inert. The weight reduction from
7379-432: The ET, thus protecting the orbiter's thermal protection system during launch. There are eight propellant-depletion sensors, four each for fuel and oxidizer. The fuel-depletion sensors are located in the bottom of the fuel tank. The oxidizer sensors are mounted in the orbiter liquid oxygen feed line manifold downstream of the feed line disconnect. During RS-25 thrusting, the orbiter general-purpose computers constantly compute
7536-473: The ET. The SRBs were jettisoned before the vehicle reached orbit, while the main engines continued to operate, and the ET was jettisoned after main engine cutoff and just before orbit insertion , which used the orbiter's two Orbital Maneuvering System (OMS) engines. At the conclusion of the mission, the orbiter fired its OMS to deorbit and reenter the atmosphere . The orbiter was protected during reentry by its thermal protection system tiles, and it glided as
7693-669: The IMU, INS, and TACAN systems, which first flew on STS-118 in August 2007. While in orbit, the crew primarily communicated using one of four S band radios, which provided both voice and data communications. Two of the S ;band radios were phase modulation transceivers , and could transmit and receive information. The other two S band radios were frequency modulation transmitters and were used to transmit data to NASA. As S band radios can operate only within their line of sight , NASA used
7850-466: The IMUs while in orbit. The star trackers are deployed while in orbit, and can automatically or manually align on a star. In 1991, NASA began upgrading the inertial measurement units with an inertial navigation system (INS), which provided more accurate location information. In 1993, NASA flew a GPS receiver for the first time aboard STS-51 . In 1997, Honeywell began developing an integrated GPS/INS to replace
8007-474: The KSC. The Space Shuttle was prepared for launch primarily in the VAB at the KSC. The SRBs were assembled and attached to the external tank on the MLP. The orbiter vehicle was prepared at the Orbiter Processing Facility (OPF) and transferred to the VAB, where a crane was used to rotate it to the vertical orientation and mate it to the external tank. Once the entire stack was assembled, the MLP
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#17328554980358164-522: The LOX tank at a bolted, flange-joint interface with the intertank. The LOX tank also includes an internal slosh baffle and a vortex baffle to dampen fluid slosh. The vortex baffle is mounted over the LOX feed outlet to reduce fluid swirl resulting from slosh and to prevent entrapment of gases in the delivered LOX. The intertank is the ET structural connection between the LOX and LH 2 tanks. Its primary functions are to receive and distribute all thrust loads from
8321-510: The RMS system should malfunction. The damaged orbiter would have been commanded by the ground to deorbit and go through landing procedures over the Pacific, with the impact area being north of Hawaii. On flight day five, Endeavour would have had a full heat shield inspection, and land on flight day eight. This mission could have marked the end of the Space Shuttle program, as it is considered unlikely that
8478-524: The RS-25 experienced multiple nozzle failures, as well as broken turbine blades. Despite the problems during testing, NASA ordered the nine RS-25 engines needed for its three orbiters under construction in May 1978. NASA experienced significant delays in the development of the Space Shuttle's thermal protection system . Previous NASA spacecraft had used ablative heat shields, but those could not be reused. NASA chose to use ceramic tiles for thermal protection, as
8635-434: The SRBs and ET to the orbiter. The ET has external cameras mounted in the brackets attached to the shuttle along with transmitters that can continue to send video data long after the shuttle and the ET have separated. Earlier tanks incorporated a range safety system to disperse tank propellants if necessary. It included a battery power source, a receiver/decoder, antennas and ordnance . Starting with STS-79 this system
8792-494: The SRBs and transfer loads between the tanks. The two SRB forward attach fittings are located 180° apart on the intertank structure. A beam is extended across the intertank structure and is mechanically fastened to the attach fittings. When the SRBs are firing, the beam will flex due to high stress loads. These loads will be transferred to the fittings. Adjoining the SRB attach fittings is a major ring frame. The loads are transferred from
8949-505: The SRBs provided structural support for the orbiter vehicle and ET, as they were the only system that was connected to the mobile launcher platform (MLP). At the time of launch, the SRBs were armed at T−5 minutes, and could only be electrically ignited once the RS-25 engines had ignited and were without issue. They each provided 12,500 kN (2,800,000 lbf) of thrust, which was later improved to 13,300 kN (3,000,000 lbf) beginning on STS-8 . After expending their fuel,
9106-558: The SRBs were jettisoned approximately two minutes after launch at an altitude of approximately 46 km (150,000 ft). Following separation, they deployed drogue and main parachutes, landed in the ocean, and were recovered by the crews aboard the ships MV Freedom Star and MV Liberty Star . Once they were returned to Cape Canaveral, they were cleaned and disassembled. The rocket motor, igniter, and nozzle were then shipped to Thiokol to be refurbished and reused on subsequent flights. The SRBs underwent several redesigns throughout
9263-528: The SWT was accomplished by eliminating portions of stringers (structural stiffeners running the length of the hydrogen tank), using fewer stiffener rings and by modifying major frames in the hydrogen tank. Also, significant portions of the tank were milled differently so as to reduce thickness, and the weight of the ET's aft solid rocket booster attachments was reduced by using a stronger, yet lighter and less expensive titanium alloy. The Super Lightweight Tank (SLWT)
9420-399: The Space Shuttle through ascent, orbit, and reentry, but could not support an entire mission. The five GPCs were separated in three separate bays within the mid-deck to provide redundancy in the event of a cooling fan failure. After achieving orbit, the crew would switch some of the GPCs functions from guidance, navigation, and control (GNC) to systems management (SM) and payload (PL) to support
9577-519: The Space Shuttle to launch large satellites, and required it to be capable of lifting 29,000 kg (65,000 lb) to an eastward LEO or 18,000 kg (40,000 lb) into a polar orbit . The satellite designs also required that the Space Shuttle have a 4.6 by 18 m (15 by 60 ft) payload bay. NASA evaluated the F-1 and J-2 engines from the Saturn rockets , and determined that they were insufficient for
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#17328554980359734-407: The Space Shuttle. The external tank's orange color, which would become iconic of the Space Shuttle program, is the color of the spray-on foam insulation. The first two tanks, used for STS-1 and STS-2 , were painted white to protect the tanks from ultraviolet light during the extended time that the shuttle spent on the launch pad prior to launch. NASA engineer Farouk Huneidi told the agency that
9891-578: The Spacelab module through a 2.7 or 5.8 m (8.72 or 18.88 ft) tunnel that connected to the airlock. The Spacelab equipment was primarily stored in pallets, which provided storage for both experiments as well as computer and power equipment. Spacelab hardware was flown on 28 missions through 1999 and studied subjects including astronomy, microgravity, radar, and life sciences. Spacelab hardware also supported missions such as Hubble Space Telescope (HST) servicing and space station resupply. The Spacelab module
10048-567: The aft seating location, and also controlled the data on the HUD. In 1998, Atlantis was upgraded with the Multifunction Electronic Display System (MEDS), which was a glass cockpit upgrade to the flight instruments that replaced the eight MCDS display units with 11 multifunction colored digital screens. MEDS was flown for the first time in May 2000 on STS-101 , and the other orbiter vehicles were upgraded to it. The aft section of
10205-450: The aft surfaces prevents liquified air from pooling in the intertank. The middle cylinder of the oxygen tank, and the propellant lines, could withstand the expected depths of frost accumulation condensed from humidity, but the orbiter could not take the damage from ice breaking free. The thermal protection system weighs 4,823 lb (2,188 kg). Development of the ETs thermal protection system
10362-465: The anti-geyser line. This line paralleled the oxygen feed line, providing a circulation path for liquid oxygen. This reduces accumulation of gaseous oxygen in the feed line during prelaunch tanking (loading of the LOX). After propellant loading data from ground tests and the first few Space Shuttle missions were assessed, the anti-geyser line was removed for subsequent missions. The total length and diameter of
10519-401: The associated propellant tanks. The AJ10 engines used monomethylhydrazine (MMH) oxidized by dinitrogen tetroxide (N 2 O 4 ). The pods carried a maximum of 2,140 kg (4,718 lb) of MMH and 3,526 kg (7,773 lb) of N 2 O 4 . The OMS engines were used after main engine cut-off (MECO) for orbital insertion. Throughout the flight, they were used for orbit changes, as well as
10676-549: The built-in hold at T−9 minutes, the countdown was automatically controlled by the Ground Launch Sequencer (GLS) at the LCC, which stopped the countdown if it sensed a critical problem with any of the Space Shuttle's onboard systems. At T−3 minutes 45 seconds, the engines began conducting gimbal tests, which were concluded at T−2 minutes 15 seconds. The ground Launch Processing System handed off
10833-461: The bulk of the ET, and was 29 m (96.7 ft) tall. The orbiter vehicle was attached to the ET at two umbilical plates, which contained five propellant and two electrical umbilicals, and forward and aft structural attachments. The exterior of the ET was covered in orange spray-on foam to allow it to survive the heat of ascent. The ET provided propellant to the Space Shuttle Main Engines from liftoff until main engine cutoff. The ET separated from
10990-540: The contract to build the orbiter to North American Rockwell. In August 1973, the external tank contract to Martin Marietta , and in November the solid-rocket booster contract to Morton Thiokol . On June 4, 1974, Rockwell began construction on the first orbiter, OV-101, dubbed Constitution, later to be renamed Enterprise . Enterprise was designed as a test vehicle, and did not include engines or heat shielding. Construction
11147-477: The control to the orbiter vehicle's GPCs at T−31 seconds. At T−16 seconds, the GPCs armed the SRBs, the sound suppression system (SPS) began to drench the MLP and SRB trenches with 1,100,000 L (300,000 U.S. gal) of water to protect the orbiter vehicle from damage by acoustical energy and rocket exhaust reflected from the flame trench and MLP during lift-off. At T−10 seconds, hydrogen igniters were activated under each engine bell to quell
11304-413: The damaged orbiter. This mission plan would result in heavy fuel consumption. The third concept would be for the damaged orbiter to grapple the rescue orbiter using its RMS, eliminating the need for station-keeping. The rescue orbiter would then transfer crew using its RMS, as in the second option, and would be more fuel efficient than the station-keeping option. The concept that was eventually decided upon
11461-408: The damaged shuttle. It was unclear whether this would be practical, as the forward structure of either orbiter could collide with the payload bay of the other, resulting in damage to both orbiters. The second option that was evaluated, would be for the rescue orbiter to rendezvous with the damaged orbiter, and perform station-keeping while using its Remote Manipulator System (RMS) to transfer crew from
11618-635: The delivered LH 2 . The baffle is located at the siphon outlet just above the aft dome of the LH 2 tank. This outlet transmits the liquid hydrogen from the tank through a 17 inches (430 mm) line to the left aft umbilical. The liquid hydrogen feed line flow rate is 465 lb/s (12,700 kg/min) with the main engines at 104% or a maximum flow of 47,365 US gal/min (2.9883 m /s). The ET thermal protection system consists primarily of spray-on foam insulation (SOFI), plus preformed foam pieces and premolded ablator materials. The system also includes
11775-421: The deorbit burn prior to reentry. Each OMS engine produced 27,080 N (6,087 lbf) of thrust, and the entire system could provide 305 m/s (1,000 ft/s) of velocity change . The orbiter was protected from heat during reentry by the thermal protection system (TPS), a thermal soaking protective layer around the orbiter. In contrast with previous US spacecraft, which had used ablative heat shields,
11932-507: The development of a space shuttle to bring people and cargo to low Earth orbit (LEO), as well as a space tug for transfers between orbits and the Moon, and a reusable nuclear upper stage for deep space travel. After the release of the Space Shuttle Task Group report, many aerospace engineers favored the Class III, fully reusable design because of perceived savings in hardware costs. Max Faget ,
12089-600: The ease of refurbishing them for reuse after they landed in the ocean. In January 1972, President Richard Nixon approved the Shuttle, and NASA decided on its final design in March. The development of the Space Shuttle Main Engine (SSME) remained the responsibility of Rocketdyne, and the contract was issued in July 1971, and updated SSME specifications were submitted to Rocketdyne in that April. That August, NASA awarded
12246-479: The effects of aerodynamic and thermal stresses during launch and reentry. The beginning of the development of the RS-25 Space Shuttle Main Engine was delayed for nine months while Pratt & Whitney challenged the contract that had been issued to Rocketdyne. The first engine was completed in March 1975, after issues with developing the first throttleable, reusable engine. During engine testing,
12403-569: The engines before the oxidizer pumps cavitate (run dry). In addition, 1,100 lb (500 kg) of liquid hydrogen are loaded over and above that required by the 6:1 oxidizer–fuel engine mixture ratio. This assures that cutoff from the depletion sensors is fuel-rich; oxidizer-rich engine shutdowns can cause burning and severe erosion of engine components, potentially leading to loss of the vehicle and crew. Unexplained, erroneous readings from fuel depletion sensors have delayed several shuttle launch attempts, most notably STS-122 . On December 18, 2007,
12560-499: The engines during powered flight and fly the orbiter during unpowered flight. Both seats also had rudder controls, to allow rudder movement in flight and nose-wheel steering on the ground. The orbiter vehicles were originally installed with the Multifunction CRT Display System (MCDS) to display and control flight information. The MCDS displayed the flight information at the commander and pilot seats, as well as at
12717-662: The external tank was Lockheed Martin (previously Martin Marietta ), New Orleans, Louisiana. The tank was manufactured at the Michoud Assembly Facility , New Orleans , and was transported to Kennedy Space Center by barge . The ET has three primary structures: an LOX tank, an intertank, and an LH 2 tank. Both tanks are constructed of aluminium alloy skins with support or stability frames as required. The intertank aluminium structure utilizes skin stringers with stabilizing frames. The primary aluminium materials used for all three structures are 2195 and 2090 alloys. AL 2195
12874-592: The feasibility of reusable boosters. This became the basis for the aerospaceplane , a fully reusable spacecraft that was never developed beyond the initial design phase in 1962–1963. Beginning in the early 1950s, NASA and the Air Force collaborated on developing lifting bodies to test aircraft that primarily generated lift from their fuselages instead of wings, and tested the NASA M2-F1 , Northrop M2-F2 , Northrop M2-F3 , Northrop HL-10 , Martin Marietta X-24A , and
13031-603: The final decision to scrub a launch was announced. In addition to the weather at the launch site, conditions had to be acceptable at one of the Transatlantic Abort Landing sites and the SRB recovery area. The mission crew and the Launch Control Center (LCC) personnel completed systems checks throughout the countdown. Two built-in holds at T−20 minutes and T−9 minutes provided scheduled breaks to address any issues and additional preparation. After
13188-435: The first EVA, Megan McArthur, Andrew Feustel and John Grunsfeld would have set up a tether between the airlocks. They would have also transferred a large size Extravehicular Mobility Unit (EMU) and, after McArthur had repressurized, transferred McArthur's EMU back to Atlantis . Afterwards they would have repressurized on Endeavour , ending flight day two activities. The final two EVA were planned for flight day three. During
13345-518: 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-5 , until the loss of Challenger , the crew wore one-piece light blue nomex flight suits and partial-pressure helmets. After the Challenger disaster, the crew members wore the Launch Entry Suit (LES),
13502-476: The first time NASA performed a crewed first-flight of a spacecraft. On April 12, 1981, the Space Shuttle launched for the first time, and was piloted by John Young and Robert Crippen . During the two-day mission, Young and Crippen tested equipment on board the shuttle, and found several of the ceramic tiles had fallen off the top side of the Columbia . NASA coordinated with the Air Force to use satellites to image
13659-441: The first, Grunsfeld would have depressurized on Endeavour in order to assist Gregory Johnson and Michael Massimino in transferring an EMU to Atlantis . He and Johnson would then repressurize on Endeavour , and Massimino would have gone back to Atlantis . He, along with Scott Altman and Michael Good would have taken the rest of the equipment and themselves to Endeavour during the final EVA. They would have been standing by in case
13816-421: The fittings to the major ring frame which then distributes the tangential loads to the intertank skin. Two panels of the intertank skin, called the thrust panels, distribute the concentrated axial SRB thrust loads to the LOX and LH 2 tanks and to adjacent intertank skin panels. These adjacent panels are made up of six stringer-stiffened panels. The intertank also functions as a protective compartment for housing
13973-552: The flange for attaching the LH 2 tank to the intertank. The aft major ring receives orbiter-induced loads from the aft orbiter support struts and SRB-induced loads from the aft SRB support struts. The remaining three ring frames distribute orbiter thrust loads and LOX feedline support loads. Loads from the frames are then distributed through the barrel skin panels. The LH 2 tank has a volume of 53,488 cubic feet (1,514.6 m ) at 29.3 psi (202 kPa) and −423 °F (−252.8 °C) (cryogenic). The forward and aft domes have
14130-624: The flight deck contained windows looking into the payload bay, as well as an RHC to control the Remote Manipulator System during cargo operations. Additionally, the aft flight deck had monitors for a closed-circuit television to view the cargo bay. The mid-deck contained the crew equipment storage, sleeping area, galley, medical equipment, and hygiene stations for the crew. The crew used modular lockers to store equipment that could be scaled depending on their needs, as well as permanently installed floor compartments. The mid-deck contained
14287-491: The forward separation motors and the parachute systems that were used during recovery. The rocket nozzles could gimbal up to 8° to allow for in-flight adjustments. The rocket motors were each filled with a total 500,000 kg (1,106,640 lb) of solid rocket propellant ( APCP + PBAN ), and joined in the Vehicle Assembly Building (VAB) at KSC. In addition to providing thrust during the first stage of launch,
14444-402: The inner leading edge and 45° at the outer leading edge. Each wing had an inboard and outboard elevon to provide flight control during reentry, along with a flap located between the wings, below the engines to control pitch . The orbiter's vertical stabilizer was swept backwards at 45° and contained a rudder that could split to act as a speed brake . The vertical stabilizer also contained
14601-404: The instantaneous mass of the vehicle due to the usage of the propellants. Normally, main engine cutoff is based on a predetermined velocity; however, if any two of the fuel or oxidizer sensors sense a dry condition, the engines will be shut down. The locations of the liquid oxygen sensors allow the maximum amount of oxidizer to be consumed in the engines, while allowing sufficient time to shut down
14758-560: The introduction of the SLWT were of this configuration, one LWT remained in inventory to be used if requested until the end of the shuttle era. The SLWT provided 50% of the performance increase required for the shuttle to reach the International Space Station . The reduction in weight allowed the Orbiter to carry more payload to the highly inclined orbit of the ISS . SLWT specifications LOX tank Intertank LH 2 tank The contractor for
14915-504: The largest solid-propellant motors ever flown. Each SRB was 45 m (149.2 ft) tall and 3.7 m (12.2 ft) wide, weighed 68,000 kg (150,000 lb), and had a steel exterior approximately 13 mm (.5 in) thick. The SRB's subcomponents were the solid-propellant motor, nose cone, and rocket nozzle. The solid-propellant motor comprised the majority of the SRB's structure. Its casing consisted of 11 steel sections which made up its four main segments. The nose cone housed
15072-561: The late 1950s, the Air Force began developing the partially reusable X-20 Dyna-Soar . The Air Force collaborated with NASA on the Dyna-Soar and began training six pilots in June 1961. The rising costs of development and the prioritization of Project Gemini led to the cancellation of the Dyna-Soar program in December 1963. In addition to the Dyna-Soar, the Air Force had conducted a study in 1957 to test
15229-489: The later cases due to hydrogen leaks at this connection. This requires complete draining of the tanks and removal of all hydrogen via helium gas purge, a 20-hour process, before technicians can inspect and repair problems. A cap mounted to the swing-arm on the fixed service structure covers the oxygen tank vent on top of the ET during the countdown and is retracted about two minutes before lift-off. The cap siphons off oxygen vapor that threatens to form large ice accumulations on
15386-467: The launch of STS-125, since the crew of Atlantis would only have about three weeks of consumables after launch. The mission was first rolled out in September 2008 to Launch Complex 39B two weeks after the STS-125 shuttle was rolled out to Launch Complex 39A , creating a rare scenario in which two shuttles were on launch pads at the same time. In October 2008, however, STS-125 was delayed and rolled back to
15543-486: The launch pad, the Space Shuttle was used to verify the proper positioning of the launch complex hardware. Enterprise was taken back to California in August 1979, and later served in the development of the SLC-6 at Vandenberg AFB in 1984. On November 24, 1980, Columbia was mated with its external tank and solid-rocket boosters, and was moved to LC-39 on December 29. The first Space Shuttle mission, STS-1 , would be
15700-430: The leading edge of Space Shuttle Columbia 's wing at a few hundred miles per hour. The impact is believed to have damaged one comparatively large reinforced carbon-carbon panel on the leading edge of the left wing, believed to be about the size of a basketball which then allowed super-heated gas to enter the wing superstructure several days later during re-entry. This resulted in the destruction of Columbia and
15857-405: The liquid hydrogen tank. One of the liquid oxygen tank umbilical valves is for liquid oxygen, the other for gaseous oxygen. The liquid hydrogen tank umbilical has two valves for liquid and one for gas. The intermediate-diameter liquid hydrogen umbilical is a recirculation umbilical used only during the liquid hydrogen chill-down sequence during prelaunch. As the ET is filled, excess gaseous hydrogen
16014-452: The loss of its crew. The report determined that the external fuel tank, ET-93, "had been constructed with BX-250", a closeout foam whose blowing agent was CFC-11 and not the newer HCFC 141b. In 2005, the problem of foam shed had not been fully cured; on STS-114 , additional cameras mounted on the tank recorded a piece of foam separated from one of its Protuberance Air Load (PAL) ramps, which are designed to prevent unsteady air flow underneath
16171-543: The members on the NASA mission management team said at the time (2009) that single-pad operations were possible, but the decision was made to use both pads. The crew assigned to this mission was a subset of the STS-126 crew: Three different concept mission plans were evaluated: The first would be to use a shuttle-to-shuttle docking, where the rescue shuttle docks with the damaged shuttle, by flying upside down and backwards, relative to
16328-484: The mission created another, more humorous design depicting a St. Bernard with its traditional barrel of brandy replaced by the Hubble Space Telescope. The final flight crew though were unsatisfied with this as a crew patch, and contacted longtime NASA artist Tim Gagnon about creating a new one, but never formally approved a design before the mission was scrubbed. Space Shuttle The Space Shuttle
16485-437: The mission specialists who were specifically trained for their intended missions and systems. Early in the Space Shuttle program, NASA flew with payload specialists, who were typically systems specialists who worked for the company paying for the payload's deployment or operations. The final payload specialist, Gregory B. Jarvis , flew on STS-51-L , and future non-pilots were designated as mission specialists. An astronaut flew as
16642-492: The mission, the emblem "adopts many of the elements seen in a rescue organization's patch - the square cross, bold letterers and border, and simple design. The idea is that the emblem instantly identifies the rescue organization in a crowd of others. In this case, the Shuttle outlines identify the purpose of our organization." In addition, the emblem contains 11 stars, symbolizing the combined 11 crew-members who would return to earth onboard STS-400. The first flight crew assigned to
16799-401: The operational instrumentation. The LH 2 tank is the bottom portion of the ET. The tank is constructed of four cylindrical barrel sections, a forward dome, and an aft dome. The barrel sections are joined together by five major ring frames. These ring frames receive and distribute loads. The forward dome-to-barrel frame distributes the loads applied through the intertank structure and is also
16956-434: The operational mission. The Space Shuttle was not launched if its flight would run from December to January, as its flight software would have required the orbiter vehicle's computers to be reset at the year change. In 2007, NASA engineers devised a solution so Space Shuttle flights could cross the year-end boundary. Space Shuttle missions typically brought a portable general support computer (PGSC) that could integrate with
17113-424: The optimal design for a reusable spacecraft, and issued study contracts to General Dynamics , Lockheed , McDonnell Douglas , and North American Rockwell . In July 1969, the Space Shuttle Task Group issued a report that determined the Shuttle would support short-duration crewed missions and space station, as well as the capabilities to launch, service, and retrieve satellites. The report also created three classes of
17270-436: The orange foam itself was sufficiently protected, and the ET was no longer covered in latex paint beginning on STS-3. A light-weight tank (LWT) was first flown on STS-6, which reduced tank weight by 4,700 kg (10,300 lb). The LWT's weight was reduced by removing components from the hydrogen tank and reducing the thickness of some skin panels. In 1998, a super light-weight ET (SLWT) first flew on STS-91 . The SLWT used
17427-414: The orbiter and the two solid rocket boosters were also routed through those umbilicals. Although the external tanks were always discarded, it may have been possible to re-use them in orbit. Plans for re-use ranged from incorporation into a space station as extra living or research space, as rocket fuel tanks for interplanetary missions (e.g. Mars), to raw materials for orbiting factories. Another concept
17584-437: The orbiter vehicle 18 seconds after engine cutoff and could be triggered automatically or manually. At the time of separation, the orbiter vehicle retracted its umbilical plates, and the umbilical cords were sealed to prevent excess propellant from venting into the orbiter vehicle. After the bolts attached at the structural attachments were sheared, the ET separated from the orbiter vehicle. At the time of separation, gaseous oxygen
17741-467: The orbiter vehicle and would be removed and replaced in between flights. The RS-25 is a staged-combustion cycle cryogenic engine that used liquid oxygen and hydrogen and had a higher chamber pressure than any previous liquid-fueled rocket. The original main combustion chamber operated at a maximum pressure of 226.5 bar (3,285 psi). The engine nozzle is 287 cm (113 in) tall and has an interior diameter of 229 cm (90.3 in). The nozzle
17898-500: The orbiter vehicle's computers and communication suite, as well as monitor scientific and payload data. Early missions brought the Grid Compass , one of the first laptop computers, as the PGSC, but later missions brought Apple and Intel laptops. The payload bay comprised most of the orbiter vehicle's fuselage , and provided the cargo-carrying space for the Space Shuttle's payloads. It
18055-535: The orbiter vehicle's heat, and were opened upon reaching orbit for heat rejection. The orbiter could be used in conjunction with a variety of add-on components depending on the mission. This included orbital laboratories, boosters for launching payloads farther into space, the Remote Manipulator System (RMS), and optionally the EDO pallet to extend the mission duration. To limit the fuel consumption while
18212-512: The orbiter was docked at the ISS, the Station-to-Shuttle Power Transfer System (SSPTS) was developed to convert and transfer station power to the orbiter. The SSPTS was first used on STS-118, and was installed on Discovery and Endeavour . The Remote Manipulator System (RMS), also known as Canadarm, was a mechanical arm attached to the cargo bay. It could be used to grasp and manipulate payloads, as well as serve as
18369-408: The orbiter. The plates help maintain alignment among the umbilicals. Physical strength at the umbilical plates is provided by bolting corresponding umbilical plates together. When the orbiter GPCs command external tank separation, the bolts are severed by pyrotechnic devices. The ET has five propellant umbilical valves that interface with orbiter umbilicals: two for the liquid oxygen tank and three for
18526-544: The originally specified thrust at 100%, but had the RS-25 operate at higher thrust. RS-25 upgrade versions were denoted as Block I and Block II. 109% thrust level was achieved with the Block II engines in 2001, which reduced the chamber pressure to 207.5 bars (3,010 psi), as it had a larger throat area. The normal maximum throttle was 104 percent, with 106% or 109% used for mission aborts. The Orbital Maneuvering System (OMS) consisted of two aft-mounted AJ10-190 engines and
18683-569: The paint did not actually protect the foam. Martin Marietta (now part of Lockheed Martin ) reduced weight by leaving the rust-colored spray-on insulation unpainted beginning with STS-3 , saving approximately 272 kg (600 lb ). The original ET is informally known as the Standard Weight Tank (SWT) and was fabricated from 2219 aluminum alloy , a high-strength aluminum-copper alloy used for many aerospace applications. After STS-4 , several hundred pounds were eliminated by removing
18840-454: The program would have been able to continue with just two remaining orbiters , Discovery and Endeavour . On Thursday, 21 May 2009, NASA officially released Endeavour from the rescue mission, freeing the orbiter to begin processing for STS-127 . This also allowed NASA to continue processing LC-39B for the upcoming Ares I-X launch, as during the stand-down period, NASA installed a new lightning protection system, similar to those found on
18997-405: The program's lifetime. STS-6 and STS-7 used SRBs 2,300 kg (5,000 lb) lighter due to walls that were 0.10 mm (.004 in) thinner, but were determined to be too thin to fly safely. Subsequent flights until STS-26 used cases that were 0.076 mm (.003 in) thinner than the standard-weight cases, which reduced 1,800 kg (4,000 lb). After the Challenger disaster as
19154-400: The propellant for the Space Shuttle Main Engines, and connected the orbiter vehicle with the solid rocket boosters. The ET was 47 m (153.8 ft) tall and 8.4 m (27.6 ft) in diameter, and contained separate tanks for liquid oxygen and liquid hydrogen. The liquid oxygen tank was housed in the nose of the ET, and was 15 m (49.3 ft) tall. The liquid hydrogen tank comprised
19311-461: The requirements of the Space Shuttle; in July 1971, it issued a contract to Rocketdyne to begin development on the RS-25 engine. NASA reviewed 29 potential designs for the Space Shuttle and determined that a design with two side boosters should be used, and the boosters should be reusable to reduce costs. NASA and the Air Force elected to use solid-propellant boosters because of the lower costs and
19468-682: The reusability of the orbiter required a multi-use heat shield. During reentry, the TPS experienced temperatures up to 1,600 °C (3,000 °F), but had to keep the orbiter vehicle's aluminum skin temperature below 180 °C (350 °F). The TPS primarily consisted of four types of tiles. The nose cone and leading edges of the wings experienced temperatures above 1,300 °C (2,300 °F), and were protected by reinforced carbon-carbon tiles (RCC). Thicker RCC tiles were developed and installed in 1998 to prevent damage from micrometeoroid and orbital debris , and were further improved after RCC damage caused in
19625-449: The same modified ellipsoidal shape. For the forward dome, mounting provisions are incorporated for the LH 2 vent valve, the LH 2 pressurization line fitting, and the electrical feed-through fitting. The aft dome has a manhole fitting for access to the LH 2 feedline screen and a support fitting for the LH 2 feedline. The LH 2 tank also has a vortex baffle to reduce swirl resulting from slosh and to prevent entrapment of gases in
19782-529: The shuttle could then be constructed of lightweight aluminum , and the tiles could be individually replaced as needed. Construction began on Columbia on March 27, 1975, and it was delivered to the KSC on March 25, 1979. At the time of its arrival at the KSC, Columbia still had 6,000 of its 30,000 tiles remaining to be installed. However, many of the tiles that had been originally installed had to be replaced, requiring two years of installation before Columbia could fly. On January 5, 1979, NASA commissioned
19939-409: The stagnant gas inside the cones before ignition. Failure to burn these gases could trip the onboard sensors and create the possibility of an overpressure and explosion of the vehicle during the firing phase. The hydrogen tank's prevalves were opened at T−9.5 seconds in preparation for engine start. Space Shuttle external tank The Space Shuttle external tank ( ET ) was the component of
20096-431: The tank had not changed since 1993." The "new" foam containing HCFC 141b was first used on the aft dome portion of ET-82 during the flight of STS-79 in 1996. Use of HCFC 141b was expanded to the ETs area, or larger portions of the tank, starting with ET-88, which flew on STS-86 in 1997. During the lift-off of STS-107 on January 16, 2003, a piece of foam insulation detached from one of the tank's bipod ramps and struck
20253-641: The tank's cable trays and pressurization lines during ascent. The PAL ramps consist of manually sprayed layers of foam, and are more likely to become a source of debris. That piece of foam did not impact the orbiter. Reports published concurrent with the STS-114 mission suggest that excessive handling of the ET during modification and upgrade may have contributed to the foam loss on Discovery 's Return to Flight mission. However, three shuttle missions ( STS-121 , STS-115 , and STS-116 ) were later conducted, all with "acceptable" levels of foam loss. However, on STS-118
20410-418: The underside of Columbia , and determined there was no damage. Columbia reentered the atmosphere and landed at Edwards AFB on April 14. NASA conducted three additional test flights with Columbia in 1981 and 1982. On July 4, 1982, STS-4 , flown by Ken Mattingly and Henry Hartsfield , landed on a concrete runway at Edwards AFB. President Ronald Reagan and his wife Nancy met the crew, and delivered
20567-467: The upper parts of the orbiter vehicle were coated in tiles of white low-temperature reusable surface insulation with similar composition, which provided protection for temperatures below 650 °C (1,200 °F). The payload bay doors and parts of the upper wing surfaces were coated in reusable Nomex felt surface insulation or in beta cloth , as the temperature there remained below 370 °C (700 °F). The Space Shuttle external tank (ET) carried
20724-429: The use of phenolic thermal insulators to preclude air liquefaction. Thermal isolators are required for liquid hydrogen tank attachments to preclude the liquefaction of air on exposed metal, and to reduce heat flow into the liquid hydrogen. While the warmer liquid oxygen results in fewer thermal requirements, the aluminum of the liquid oxygen tank forward areas require protection from aeroheating . Meanwhile, insulation on
20881-512: Was 1,323 days. Space Shuttle components include the Orbiter Vehicle (OV) with three clustered Rocketdyne RS-25 main engines, a pair of recoverable solid rocket boosters (SRBs), and the expendable external tank (ET) containing liquid hydrogen and liquid oxygen . The Space Shuttle was launched vertically , like a conventional rocket, with the two SRBs operating in parallel with the orbiter's three main engines , which were fueled from
21038-462: Was 18 m (60 ft) long and 4.6 m (15 ft) wide, and could accommodate cylindrical payloads up to 4.6 m (15 ft) in diameter. Two payload bay doors hinged on either side of the bay, and provided a relatively airtight seal to protect payloads from heating during launch and reentry. Payloads were secured in the payload bay to the attachment points on the longerons . The payload bay doors served an additional function as radiators for
21195-490: Was Space Shuttle-specific software that provided control through all phases of flight. During ascent, maneuvering, reentry, and landing, the four PASS GPCs functioned identically to produce quadruple redundancy and would error check their results. In case of a software error that would cause erroneous reports from the four PASS GPCs, a fifth GPC ran the Backup Flight System, which used a different program and could control
21352-618: Was a modified airport jet bridge that was used to assist astronauts to egress from the orbiter after landing, where they would undergo their post-mission medical checkups. The Astrovan transported astronauts from the crew quarters in the Operations and Checkout Building to the launch pad on launch day. The NASA Railroad comprised three locomotives that transported SRB segments from the Florida East Coast Railway in Titusville to
21509-447: Was a modified version of the third concept. The rescue orbiter would use its RMS to grapple the end of the damaged orbiter's RMS. After its most recent mission ( STS-123 ), Endeavour was taken to the Orbiter Processing Facility for routine maintenance. Following the maintenance, Endeavour was on stand-by for STS-326 which would have been flown in the case that STS-124 would not have been able to return to Earth safely. Stacking of
21666-565: Was announced that NASA was evaluating conducting both launches from Complex 39A in order to avoid further delays to Ares I-X , which, at the time, was scheduled for launch from LC-39B in the September 2009 timeframe. It was planned that after the STS-125 mission in October 2008, Launch Complex 39B would undergo the conversion for use in Project Constellation for the Ares I-X rocket. Several of
21823-462: Was carried for 5.6 km (3.5 mi) to Launch Complex 39 by one of the crawler-transporters . After the Space Shuttle arrived at one of the two launchpads, it would connect to the Fixed and Rotation Service Structures, which provided servicing capabilities, payload insertion, and crew transportation. The crew was transported to the launch pad at T−3 hours and entered the orbiter vehicle, which
21980-565: Was closed at T−2 hours. Liquid oxygen and hydrogen were loaded into the external tank via umbilicals that attached to the orbiter vehicle, which began at T−5 hours 35 minutes. At T−3 hours 45 minutes, the hydrogen fast-fill was complete, followed 15 minutes later by the oxygen tank fill. Both tanks were slowly filled up until the launch as the oxygen and hydrogen evaporated. The launch commit criteria considered precipitation, temperatures, cloud cover, lightning forecast, wind, and humidity. The Space Shuttle
22137-660: Was completed on September 17, 1976, and Enterprise was moved to the Edwards Air Force Base to begin testing. Rockwell constructed the Main Propulsion Test Article (MPTA)-098 , which was a structural truss mounted to the ET with three RS-25 engines attached. It was tested at the National Space Technology Laboratory (NSTL) to ensure that the engines could safely run through the launch profile. Rockwell conducted mechanical and thermal stress tests on Structural Test Article (STA)-099 to determine
22294-413: Was connected to each SRB at one forward attachment point (using a crossbeam through the intertank) and one aft bracket, and it was connected to the orbiter at one forward attachment bipod and two aft bipods. In the aft attachment area, there were also umbilicals that carried fluids , gases , electrical signals and electrical power between the tank and the orbiter. Electrical signals and controls between
22451-535: Was entirely reliant on its main computer, the Data Processing System (DPS). The DPS controlled the flight controls and thrusters on the orbiter, as well as the ET and SRBs during launch. The DPS consisted of five general-purpose computers (GPC), two magnetic tape mass memory units (MMUs), and the associated sensors to monitor the Space Shuttle components. The original GPC used was the IBM AP-101B , which used
22608-657: Was equipped with an avionics system to provide information and control during atmospheric flight. Its avionics suite contained three microwave scanning beam landing systems , three gyroscopes , three TACANs , three accelerometers , two radar altimeters , two barometric altimeters , three attitude indicators , two Mach indicators , and two Mode C transponders . During reentry, the crew deployed two air data probes once they were traveling slower than Mach 5. The orbiter had three inertial measuring units (IMU) that it used for guidance and navigation during all phases of flight. The orbiter contains two star trackers to align
22765-634: Was first flown in 1975, and was used for the ALT and ferrying the orbiter from Edwards AFB to the KSC on all missions prior to 1991. A second SCA (N911NA) was acquired in 1988, and was first used to transport Endeavour from the factory to the KSC. Following the retirement of the Space Shuttle, N905NA was put on display at the JSC, and N911NA was put on display at the Joe Davies Heritage Airpark in Palmdale, California . The Crew Transport Vehicle (CTV)
22922-479: Was first flown in 1998 on STS-91 and was used for all subsequent missions with two exceptions ( STS-99 and STS-107 ). The SLWT had basically the same design as the LWT except that it used an aluminium-lithium alloy ( Al 2195 ) for a large part of the tank structure. This alloy provided a significant reduction in tank weight (about 7,000 pounds or 3,175 kg) over the LWT. Manufacture also included friction stir welding technology. Although all ETs produced after
23079-403: Was later improved to 270,000 kg (586,000 lb). The Spacelab module was a European-funded pressurized laboratory that was carried within the payload bay and allowed for scientific research while in orbit. The Spacelab module contained two 2.7 m (9 ft) segments that were mounted in the aft end of the payload bay to maintain the center of gravity during flight. Astronauts entered
23236-406: Was located below the flight deck and was where the galley and crew bunks were set up, as well as three or four crew member seats. The mid-deck contained the airlock, which could support two astronauts on an extravehicular activity (EVA), as well as access to pressurized research modules. An equipment bay was below the mid-deck, which stored environmental control and waste management systems. On
23393-591: Was moved to the Marshall Space Flight Center (MSFC) on March 13, 1978. Enterprise underwent shake tests in the Mated Vertical Ground Vibration Test, where it was attached to an external tank and solid rocket boosters, and underwent vibrations to simulate the stresses of launch. In April 1979, Enterprise was taken to the KSC, where it was attached to an external tank and solid rocket boosters, and moved to LC-39 . Once installed at
23550-587: Was never used). The Johnson Space Center (JSC) served as the central point for all Shuttle operations and the MSFC was responsible for the main engines, external tank, and solid rocket boosters. The John C. Stennis Space Center handled main engine testing, and the Goddard Space Flight Center managed the global tracking network. The orbiter had design elements and capabilities of both a rocket and an aircraft to allow it to launch vertically and then land as
23707-422: Was not launched under conditions where it could have been struck by lightning , as its exhaust plume could have triggered lightning by providing a current path to ground after launch, which occurred on Apollo 12 . The NASA Anvil Rule for a Shuttle launch stated that an anvil cloud could not appear within a distance of 19 km (10 nmi). The Shuttle Launch Weather Officer monitored conditions until
23864-433: Was problematic. Anomalies in foam application were so frequent that they were treated as variances, not safety incidents. NASA had difficulty preventing fragments of foam from detaching during flight for the entire history of the program: In 1995, chlorofluorocarbon-11 (CFC-11) began to be withdrawn from large-area, machine-sprayed foams in compliance with an Environmental Protection Agency ban on CFCs under section 610 of
24021-418: Was tested on STS-2 and STS-3, and the first full mission was on STS-9. Three RS-25 engines, also known as the Space Shuttle Main Engines (SSME), were mounted on the orbiter's aft fuselage in a triangular pattern. The engine nozzles could gimbal ±10.5° in pitch, and ±8.5° in yaw during ascent to change the direction of their thrust to steer the Shuttle. The titanium alloy reusable engines were independent of
24178-444: Was the top level of the crew compartment and contained the flight controls for the orbiter. The commander sat in the front left seat, and the pilot sat in the front right seat, with two to four additional seats set up for additional crew members. The instrument panels contained over 2,100 displays and controls, and the commander and pilot were both equipped with a heads-up display (HUD) and a Rotational Hand Controller (RHC) to gimbal
24335-416: Was time to launch STS-125, Atlantis rolled out to pad 39A. The Mission would not have included the extended heatshield inspection normally performed on flight day two. Instead, an inspection would have been performed after the crew was rescued. On flight day two, Endeavour would have performed the rendezvous and grapple with Atlantis . On flight day three, the first EVA would have been performed. During
24492-466: Was to use the ET as a cargo carrier for bulky payloads. One proposal was for the primary mirror of a 7-meter aperture telescope to be carried with the tank. Another concept was the Aft Cargo Carrier (ACC). Over the years, NASA worked to reduce the weight of the ET to increase overall efficiency. The weight reduced from the ET resulted in an almost equal increase of the cargo-carrying capability of
24649-547: Was vented from the nose to cause the ET to tumble, ensuring that it would break up upon reentry. The ET was the only major component of the Space Shuttle system that was not reused, and it would travel along a ballistic trajectory into the Indian or Pacific Ocean. For the first two missions, STS-1 and STS-2 , the ET was covered in 270 kg (595 lb) of white fire-retardant latex paint to provide protection against damage from ultraviolet radiation. Further research determined that
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