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STS-43

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AppleLink was the name of both Apple Computer 's online service for its dealers, third-party developers, and users, and the client software used to access it. Prior to the commercialization of the Internet , AppleLink was a popular service for Mac and Apple IIGS users. The service was offered from about 1986 to 1994 to various groups, before being superseded by their short-lived eWorld and finally today's multiple Apple websites .

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127-486: STS-43 , the ninth mission for Space Shuttle Atlantis , was a nine-day mission whose primary goal was launching the TDRS-E satellite (TDRS-5). The flight also tested an advanced heatpipe radiator for potential use on the then-future space station and conducted a variety of medical and materials science investigations. The launch took place on August 2, 1991 at 15:02:00   UTC (11:02   am   EDT , local time at

254-993: 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

381-487: 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,

508-497: 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

635-459: 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

762-576: 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

889-504: A message to Marcia Ivins, a shuttle communicator at Johnson Space Center . The Message read: "Hello Earth! Greetings from the STS-43 Crew. This is the first AppleLink from space. Having a GREAT time, wish you were here,...send cryo and RCS! Hasta la vista, baby,...we'll be back!" The AppleLink software was configured with a special Macintosh Communications ToolBox Connection Tool that interfaced to NASA 's communication system which allowed

1016-477: 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

1143-528: 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

1270-517: 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

1397-541: 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

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1524-481: 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

1651-665: 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)

1778-661: 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

1905-645: 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

2032-459: A service that had no obviously measurable income. Eventually Apple approached Steve Case of Quantum Computer Services , who ran a somewhat similar system for users of the Commodore 64 . They reached an agreement in which Apple and Quantum would develop a new system known as AppleLink Personal Edition, which would be intended for end-users until all existing AppleLink content could be moved over and

2159-410: 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,

2286-761: 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

2413-505: 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

2540-428: 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

2667-452: 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

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2794-508: 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

2921-620: The AppleLink Package format to combine and compress the two forks of a Macintosh file into one for storage and sending. Apple also developed their Communications Control Language ( CCL ) for AppleLink, a language still used in a very similar form for today's Macintosh modem scripts. The " back end " of the AppleLink system was hosted on General Electric 's Information Services ( GEIS ) (division) Mark III time-sharing mainframes and worldwide communications network . AppleLink translated

3048-749: 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

3175-558: 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

3302-592: 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

3429-474: The Project Gemini , and first used music to wake up a flight crew during Apollo 15 . Each track is specially chosen, often by the astronauts' families, and usually has a special meaning to an individual member of the crew, or is applicable to their daily activities. Space Shuttle The Space Shuttle is a retired, partially reusable low Earth orbital spacecraft system operated from 1981 to 2011 by

3556-543: 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

3683-619: 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

3810-499: The desktop metaphor of the Macintosh Finder to encompass the areas on the remote server site. These were displayed as folders and files just as local folders and files were. In addition, there was a set of public bulletin boards , and the ability to use email via the service—although initially only between AppleLink users. File transfer for drivers and system software was another important role, and for this Apple created

3937-529: 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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4064-484: 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

4191-445: 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

4318-543: The Air Force Maui Optical Site (AMOS) experiment. TDRS-E, which became TDRS-5 on orbit, was successfully boosted to geosynchronous orbit at more than 22,000 miles (35,400 km (22,000 mi)) above Earth by two firings of the Inertial Upper Stage (IUS) booster, the last of which occurred approximately 12½ hours into the mission. TDRS then deployed its antennas and solar panels, and separation from

4445-452: 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

4572-518: 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

4699-669: 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 ;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

4826-466: 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

4953-588: The IUS took place less than 45 minutes later. The TDRS network of satellites provides the vital communication link between Earth and low-orbiting spacecraft such as the Space Shuttle. Until the STS-43 deployment, there were three TDRS spacecraft on orbit above the equator : two were in the west position over the Pacific Ocean , southwest of Hawaii . TDRS-4 was in the east position over the northeast corner of Brazil . TDRS-B

5080-474: 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

5207-524: 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

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5334-505: 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,

5461-558: 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

5588-504: The STS-43 crew. This is the first AppleLink from space. Having a GREAT time, wish you were here, ... send cryo and RCS! Hasta la vista, baby, ... we'll be back! The crew experienced some minor problems, none of them critical to the safety or success of the mission. A cooling system for Auxiliary Power Unit (APU 2) failed to activate during an on-orbit test. APU 2 is one of three redundant systems which provide hydraulic pressurization to orbiter steering systems during entry and landing. APU 2

5715-463: The Shuttle to call up GEIS' network from space. The Shuttle's e-mail address was secret, but exposed to GEIS' e-mail network as any other AppleLink address. To avoid a deluge of incoming mail resulting from the publicity of the event, Apple set up a number of obvious " honeypot " addresses not really used by the Shuttle crew, such as STS43@APPLELINK. Most of the well-wishers' e-mail went there, rather than to

5842-399: 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

5969-519: 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

6096-578: 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

6223-580: 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

6350-567: 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

6477-401: 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

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6604-549: 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

6731-461: 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

6858-540: 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

6985-477: 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

7112-421: 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,

7239-507: 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 ,

7366-600: 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

7493-479: 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,

7620-466: The end of 1992 to host a private-label system known as eWorld . By this time AOL had grown to be both much larger than GEIS, so all AppleLink content was to be moved over as well, allowing the GEIS service to be shut down. The eWorld software was basically a version of the original AOL software with custom graphics, giving it a distinctive look. The system was ready for launch in mid-1994. However, by this point

7747-487: The end-users' connection fees of about $ 15 an hour during business hours (which Apple rebilled to the users). For some years prior to the discontinuation of the system, GEIS maintained a number of employees on the campus of Apple's Cupertino, California , headquarters, co-located with the Apple On-Line Services organization. Repeated attempts to negotiate a lower cost failed, and Apple management chafed at paying for

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7874-499: 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

8001-592: 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

8128-649: 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

8255-518: 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),

8382-483: The first graphical user-interface design of America Online. Meanwhile, interested in selling the system to other customers, GEIS developed both DOS and eventually Windows based versions of the client software and sold the system as "DealerTalk" starting in 1986, aiming at the Apple model of manufacturers using the system to communicate with their dealers. All the systems, including the AppleLink community, were united behind

8509-476: 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

8636-518: The flight deck and the payload bay. Crew members in space and flight controllers on the ground demonstrated their ingenuity when they adapted a camera part to replace one that had not been packed for the mission. The mission was also notable for being the first one to send an email from space. On August 9, 1991, astronauts Lucid and Adamson used AppleLink to write an email from a Macintosh Portable addressed to Marsha S. Ivins at Johnson Space Center . The message read: Hello Earth! Greetings from

8763-624: 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

8890-491: 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,

9017-402: 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

9144-504: 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

9271-561: 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

9398-486: 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

9525-404: The launch site). Launch was originally set for July 23, 1991, but was moved to July 24 to allow time to replace a faulty integrated electronics assembly that controls orbiter/external tank separation. The mission was postponed again about five hours before liftoff on July 24, 1991, due to a faulty main engine controller on the number three main engine. The controller was replaced and retested; launch

9652-437: 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

9779-434: 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

9906-424: 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

10033-436: 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

10160-437: 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

10287-467: 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

10414-500: 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

10541-535: 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

10668-512: 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

10795-544: 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

10922-455: The place to turn for help because of his access to AppleLink. In the late 1980s the service was also opened up to software developers , who could use it both as an end-user support system as well as a conduit to Apple development for questions and suggestions. AppleLink used client software written in Pascal under contract to Apple by Pete Burnight / Central Coast Software . The program extended

11049-405: 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

11176-400: 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

11303-484: The rapid rise of the Internet was generally killing off all smaller online services and bulletin board systems , and online systems were generally seen as antiquated. Apple was never able to turn a profit on eWorld, and shut it down after a little over a year of operation, before it was able to supplant AppleLink. Subsequently, Apple moved all of its services and replaced all of the AppleLink content. The first step involved

11430-572: The real Atlantis address. Quantum retained rights to the AppleLink Personal Edition software, and released a version for both the Mac and Microsoft Windows machines in 1989, calling the new service America Online as Apple owned the AppleLink name. In 1991 the service had grown substantially, and the company was renamed as America Online Inc. The original AOL Macintosh software still retained within it vestiges of its GEIS/AppleLink heritage. It

11557-461: 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

11684-682: 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

11811-778: The satellite into geosynchronous orbit . TDRS-5 became the fourth member of the orbiting TDRS cluster. Secondary payloads were Space Station Heat Pipe Advanced Radiator Element (SHARE II); Shuttle Solar Backscatter Ultra-Violet (SSBUV) instrument; Tank Pressure Control Equipment (TPCE) and Optical Communications Through Windows (OCTW). Other experiments included Auroral Photography Experiment (APE-B) Protein Crystal Growth Ill (PCG Ill); Bioserve / Instrumentation Technology Associates Materials Dispersion Apparatus (BIMDA); Investigations into Polymer Membrane Processing (IPMP); Space Acceleration Measurement System (SAMS); Solid Surface Combustion Experiment (SSCE); Ultraviolet Plume imager (UVPI); and

11938-494: The scenes as part of GEIS' worldwide Quik-Comm E-mail service and could exchange mail with each other and all GEIS mail customers, using addresses like MICHAEL@APPLELINK or JOHNDOE@GEIS. This was later expanded to include Internet mail addresses. Eventually, the GEIS products were renamed BusinessTalk and after a complete system rewrite and creation of their own Macintosh client program (never incorporated into AppleLink), again renamed BusinessTalk System 2000 in 1992. During this time

12065-575: The shuttle Atlantis from the outlined configuration of the Mercury space capsule commemorates this special relationship. The energy and momentum of launch are conveyed by the gradations of blue which mark the shuttle's ascent from Earth to space. Once in Earth orbit, Atlantis' cargo bay opens to reveal the Tracking and Data Relay Satellite (TDRS) which appears in gold emphasis against the white wings of Atlantis and

12192-529: 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

12319-670: The spacecraft's altitude. The crew was kept busy with the operation of varied experiments during the nine-day flight. The Space Station Heat Pipe Advanced Radiator Element (SHARE-II) experiment tested a natural cooling process for transferring thermal energy that could serve as a cooling system for Space Station Freedom . The Solid Surface Combustion Experiment (SSCE) provided some answers about how fire behaves in microgravity. The crew also activated other previously flown materials science experiments and participated in medical experiments in support of long-duration flights. One test showed that optical fibers could provide video and audio links between

12446-585: 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. AppleLink The original AppleLink, which went online in 1985, was a service available only to Apple employees and dealers, and shortly thereafter to Apple University Consortium members. Apple's consumer 800 number in fact touted this fact, promoting your dealer as

12573-423: The stark blackness of space. As primary mission objective, the Tracking and Data Relay Satellite System (TDRSS) will enable almost continuous communication from Earth to space for future space shuttle missions. The stars on the insignia are arranged to suggest this mission's numerical designation, with four stars left of Atlantis and three to the right. NASA began a tradition of playing music to astronauts during

12700-508: The system proved itself stable enough for support services as well. Beta-test users were generally disappointed that the new service did not give them access to the "real" AppleLink, and eventually the service was released instead as America Online. Aaron Marcus and Associates, Inc. , under contract to Apple and working closely with Apple's software engineers, designed the icons, dialogue boxes and screen layout for AppleLink Personal Edition. These icons and some dialogue boxes were incorporated into

12827-625: The system, with the Windows client, also became the foundation for Microsoft's first on-line service for developers, the Microsoft Partner Network (MSPN). On August 9, 1991, AppleLink, running on a Macintosh Portable was used to send the first e-mail from space, aboard the Space Shuttle Atlantis , mission STS-43 . Atlantis astronauts Shannon Lucid and James C. Adamson with the help of Dave Crego, an engineer at Apple, sent

12954-418: 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

13081-467: 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

13208-412: The user's GUI actions into a transaction protocol that was sent into a server program running on the mainframe. The connection used a proprietary error free sliding window protocol called EF3 . Later versions upgraded this protocol to GEIS' "EFX" (Error-Free eXtended) protocol. GEIS charged fairly substantial prices to Apple, both for maintaining the service (about $ 30 million a year per year), and

13335-512: 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

13462-462: 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

13589-490: 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

13716-618: 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

13843-462: 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

13970-565: 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

14097-473: Was competing with GEIS' own consumer service, GEnie . As a result, when GEIS developed the improved EFX and upgraded AppleLink, it never released source code to Apple, supplying only a copyrighted code-resource for the protocol. Apple, encouraged by AOL's success and still wanting to turn the cost of AppleLink into a profit center, decided to re-enter the market. After a months-long RFP process that included GEIS as an unsuccessful bidder, Apple approached AOL at

14224-660: 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

14351-535: 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

14478-657: 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

14605-634: 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)

14732-403: 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

14859-406: 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

14986-528: Was lost in the Challenger accident in 1986. After STS-43, the two satellites in the west became on-orbit spares; TDRS-5, after activation, checkout and calibration, officially became the primary provider of services in the west location on October 7, 1991. It was stationed at 175° west longitude . Previously, orbiting spacecraft could communicate with Earth only when in sight of a ground tracking station – about 15 percent of each orbit. The TDRS network allows communication from 85% to 100% of an orbit, depending on

15113-591: 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

15240-587: 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

15367-422: 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

15494-502: Was not lost on GEIS engineers that it included a version of their proprietary EF3 protocol which was never Apple's intellectual property to share with Quantum. It was handed over anyway as part of the Macintosh source code, thanks to John Sculley , Apple's CEO at the time. Although no legal action was ever pursued, this further soured the technical relationship between GEIS and Apple in the final years of AppleLink, especially since by then AOL

15621-402: Was reset for August 1, 1991. Liftoff set for 11:01 a.m. delayed due to cabin pressure vent valve reading and postponed at 12:28 p.m. due to unacceptable return-to-launch site weather conditions. Launch finally occurred on August 2, 1991, without further delays. The primary payload, TDRS-E, attached to an Inertial Upper Stage (IUS), was deployed about six hours into flight, and the IUS propelled

15748-412: Was still available for use in landing. Atlantis landed on August 11, 1991, at 8:23:25 a.m. EDT, on Runway 15, at Kennedy Space Center . According to the mission's official Press Kit , the STS-43 insignia portrays the evolution and continuity of the U.S. space program by highlighting thirty years of American crewed spaceflight experience, from Project Mercury to the Space Shuttle. The emergence of

15875-418: 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

16002-444: 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

16129-547: 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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