For over 29 years engineers, space enthusiasts, and people around the world have marveled at the technological and scientific achievement that is the Space Shuttle fleet. During this time, the most complex machines ever built have proven themselves invaluable in transforming mankind’s understanding of planet Earth and the space beyond. And for 26 of those 29 years, Orbiter Discovery has stood as the rock of the Space Shuttle Program.
Space Shuttle Discovery:
The history of the Orbiter Discovery, like those of her sisters, is one filled with accomplishments, triumphs in the face of tragedies, and one of true inspiration.
Launching more times than any other space vehicle in history (a distinction she will hold for decades to come since no spaceship currently under construction, design, or research and development is slated to fly more than 10 times), Discovery’s 38 – soon to be 39 – missions place her firmly and unquestionably as the workhorse for the manned space community.
Named after four previous British ships to bear the name, Shuttle Orbiter Discovery honors the HMS Discovery used by Captain James Cook during his third and final voyage (1776-1779); the Discovery used by Henry Hudson during his 1610-1611 search for the Northwest Passage; the HMS Discovery during Captain George Nares’s British Arctic Expedition to the North Pole in 1875-1876; and the RRS Discovery, a Royal Geographical Society research vessel which was the main vessel used during Captain Robert Falcon Scott’s “Discovery Expedition” to Antarctica – and the only one of Shuttle Discovery’s namesakes still preserved as a museum.
For Discovery herself, the contract to build OV-103 was awarded to Rockwell International on January 29, 1979. Almost exactly seven months later, fabrication on Discovery’s crew module began. This was followed in June 1980 by the start of construction on Discovery’s lower fuselage.
Structural assembly of the aft-fuselage began in November 1980 with installation of aft fuselage systems beginning on December 10. System installation into the Crew Module began in Oct. 1981.
Discovery’s mid-fuselage arrived at the Palmdale assembly facility in March 1982, as did the vehicle’s elevons. Discovery’s tell-tale delta wings arrived in April that same year along with the lower-forward fuselage.
Final assembly of Discovery began on September 3, 1982 and was completed on February 25, 1983. Initial subsystem testing commenced on Feb. 28 and all subsystem testing was completed on July 26.
SpaceX
(adsbygoogle = window.adsbygoogle || []).push({});
Discovery was then rolled out of Palmdale on October 16, 1983. Three weeks later she was transported over land to Edwards Air Force Base where she was mounted on top of the Shuttle Carrier Aircraft and flown across country to the Kennedy Space Center.
Discovery arrived at Kennedy for first time on November 9, 1983 and weighed in at 6,870lbs less than sister orbiter Columbia.
The following day, Discovery was towed to an OPF (Orbiter Processing Facility) were she underwent initial receiving inspections. She was then temporarily moved to the VAB for storage on Dec. 9 before moving back to an OPF for maiden flight processing on Jan. 10, 1984.
Four months later, Discovery was moved to the VAB on May 12 and mated to an ET/SRB (External Tank/Solid Rocket Booster) set. The entire stack for STS-41D was moved to Pad-A on May 19.
On June 2, NASA conducted a 20-second Flight Readiness Firing of Discovery’s MPS (Main Propulsion System) SSMEs (Space Shuttle Main Engines). Following this test, Discovery’s maiden launch was set for June 25.
The June 25 attempt was scrubbed at the T-9 minute and holding mark due to a failure of Discovery’s back-up General Purpose Computer (GPC). Launch was rescheduled for the following day.
This attempt on June 26 proceeded nominally through the terminal count and handoff to Discovery’s onboard computers. At T-6.6 seconds, the command to start the SSMEs in sequence was issued by Discovery’s computers. Within 240 milliseconds of SSME-3’s start (SSME-3 being the first SSME to start in sequence), an RSLS (Redundant Set Launch Sequencer) abort was tripped when Discovery’s GPCs detected an anomaly in SSME-3.
In fact, Discovery’s GPCs reacted so quickly to the problem that the command to start SSME-1 (the last SSME to start in sequence) was never issued. This caused confusion in the initial seconds following the abort as the Launch Control Team could not verify the shutdown of SSME-1 (because the engine had not started and therefore could not be shut down).
Further complications arose when fire detectors on the launch pad indicated the presence of a fire. The Launch Team responded by activating emergency water outlets on the pad that doused the aft compartment of Discovery with water.
Following safing operations, the Flight Crew egressed Discovery. Under Shuttle flight rules, any start of the SSMEs is considered a “flight” of the SSMEs, with a full-up post-flight inspection and refurbishment required on all engines. To accomplish this, Discovery was rolled back to the VAB, destacked, and returned to the OPF where three new SSMEs were installed.
Discovery’s payload bay was also reconfigured at this time to incorporate elements of the STS-41F mission which was cancelled in the wake of the 41D RSLS abort.
Discovery and the STS-41D stack were returned to Pad-A on Aug. 9 ahead of an Aug. 29 launch. That launch campaign ended with the detection of a discrepancy in the flight software of Discovery’s Master Events Controller relating to the Solid Rocket Booster fire commands.
The launch countdown on Aug. 30 was delayed 6minutes 50seconds when an aircraft strayed into the no fly zone.
Finally, at 08:41:50 EDT on Aug. 30, 1984, Discovery launched on her maiden voyage with a total launch weight of 263,477lbs. The 6day 0hour 56minute flight orbited the Earth 97 times and returned to land at Edwards Air Force Base, CA.
Two months later, Discovery was launched on her second mission, STS-51A. This mission, which launched on Nov. 8, 1984, marked the first time a Shuttle orbiter deployed two communications satellites and retrieved from orbit two other communications satellites that had been deployed on a previous Shuttle mission.
Retrieval of the two communications satellites also marked the last untethered spacewalk of the Shuttle Program until 1994.
Discovery then heralded another first for the Shuttle Program on her next mission: STS-51C – the first Department of Defense flight of the Shuttle. Launched on January 24, 1985 after a one day delay due to freezing temperatures at the launch pad, STS-51C holds a frightening connection to the Challenger accident that would occur almost exactly one year later.
During routine, post-flight inspection of the twin Solid Rocket Boosters, the worst O-ring blow-by effects of any mission other than STS-51L (Challenger) were discovered. The temperature at the time of Discovery’s launch was 53-degrees F and was, at the time, the coldest temperature in which a Shuttle had been launched.
In fact, post-flight inspections of the SRBs revealed that the O-rings in both the right and left SRBs showed some degree of charring, with the center field joint of the right SRB showing an unprecedented penetration of the primary O-ring and heavily charred effects on the secondary O-ring – thus confirming the O-rings’ inability to properly seal the SRB field joints in cold temperatures one year before this very combination would claim the Challenger (STS-51L) crew and mission.
Nevertheless, Discovery successfully reached orbit and completed the 15th Space Shuttle mission without incident.
Her next flight, STS-51D, was launched exactly four years after the first Space Shuttle mission. During landing of this mission on April 17, 1985, Discovery suffered extensive brake damage and a blown tire due to the harsh conditions of the KSC runway and an inability to steer the vehicle via the nose landing gear.
All further landings were planned to occur at Edwards Air Force Base, CA until the problem could be satisfactorily resolved via the implementation of nose wheel steering.
Discovery’s next mission was launched on June 17, 1985 at 07:33 EDT. During STS-51G, three communications satellites were deployed, as well as the deployable/retrievable Spartan 1. (The Prince Sultan Salman Al Saud of Saudi Arabia flew aboard Discovery on this mission as a Payload Specialist.)
Likewise, Discovery’s next mission, STS-51I in August 1985 saw the deployment of three communications satellites; the mission also saw Discovery flying in space on her birthday – an honor that would be repeated in 2009.
STS-51I is noted as having launched in apparent unacceptable weather conditions; Discovery lifted off just as an approaching storm front reached the launch pad area.
Nonetheless, after successfully reaching orbit, Discovery deployed three communications satellites and retrieved and repaired the SYNCOM IV-3 satellite which had malfunctioned after deployment in April of that year.
Sadly, STS-51I was to be Discovery’s last mission before the loss of sister orbiter Challenger on January 28, 1986.
During the resultant two and one half year stand down, numerous safety upgrades were made throughout the orbiter fleet. After thorough review and discussions, NASA chose Discovery as the orbiter to return America to space on STS-26.
Moving to the VAB on June 21, 1988, Discovery was mated to her ET/SRB stack prior to rollout to Pad 39B on July 4. Following a Flight Readiness Firing, Discovery’s Return to Flight launch date was set for September 29 at 09:59 EDT.
On launch day, liftoff was delayed 1hour 38minutes to replace fuses in the cooling suits of two of the crew’s flight pressure suits and due to lighter than expected upper atmospheric winds.
Due to these delays, Discovery launched at 11:37 EDT – one numerical minute shy of the exact time that Challenger had launched on Jan. 28, 1986. STS-26 went on to deploy the TDRS (Tracking Data Satellite Relay)-3 satellite into orbit – a mission objective originally planned for the ill-fated STS-51L/Challenger mission.
Likewise, Discovery’s 8th flight, STS-29 in March 1989, deployed another TDRS satellite. Launch of STS-29 had initially been planned for February 18 but was delayed to allow for the replacement of suspect Liquid Oxygen Turbopumps on Discovery’s SSMEs.
Once in orbit, one of the three hydrogen cryo tanks experienced erratic pressure fluctuations and was shut down on Flight Day 1 (FD-1). The tank was reactivated on FD-3 and operated successfully for the remainder of the mission.
Discovery then spent eight months on the ground before launching on STS-33 in November 1989. Liftoff was delayed from November 20 due to a suspect integrated electronics assembly which controls ignition and separation of the twin SRBs.
During the five day mission, Discovery’s STS-33 crew carried out classified Department of Defense tasks before returning to Earth on Nov. 27.
This mission also marked the first night launch following the Challenger accident. Discovery would again make the first night launch after the Columbia accident during STS-116 in 2006.
After the successful return of Discovery from STS-33, she was processed for what is arguably her most important mission: STS-31 and the deployment of the Hubble Space Telescope.
The initial launch attempt on April 10 was scrubbed at the T-4minute mark due to a faulty valve in one of Discovery’s three APUs (Auxiliary Power Units). The APU in question was replaced and launch retargeted for April 24, 1990.
The launch attempt on April 24 was momentarily halted at the T-31second mark when computer software failed to shut a fuel valve line on the ground support equipment. The valve was quickly shut by remote command from the Launch Team and Discovery lifted off at 08:33:51 EDT.
Discovery’s crew deployed the Hubble Space Telescope into Earth orbit the following day.
STS-31 marked the 10th flight of orbiter Discovery and the first time since 1986 that two Space Shuttles occupied both KSC launch pads simultaneously, with Discovery on Pad-B and Columbia on Pad-A.
Discovery’s next mission was STS-41 (Oct. 1990), during which she deployed the Ulysses probe to study the sun. Due to Ulysses’s requirement to study the sun at multiple latitudes, the probe was launched on a course toward Jupiter, using a gravity assist from Jupiter to place itself into its proper orbit.
Ulysses’s mission lasted a whopping 19 years, finally terminating on June 30, 2009.
Discovery was then called upon to fly a DoD (Department of Defense) mission in April 1991 before once again flying on STS-48 in September that same year. During STS-48, the Upper Atmospheric Research Satellite was deployed.
Then, in January 1992, Discovery flew the STS-42 mission: an eight day microgravity scientific research mission utilizing the Spacelab module. Discovery’s only other mission in 1992 was STS-53 in the month of December. That mission carried a then-classified DoD payload to orbit and marked the last major payload flight for the DoD of the Shuttle Program.
Discovery’s next mission occurred in April 1993 on STS-56. During this flight, Discovery’s crew conducted numerous experiments with ATLAS-2 (Atmospheric Laboratory for Applications and Science-2) to collect data on the relationship between the sun’s energy output and Earth’s middle atmosphere and how these factors affect the ozone layer.
See Also
- STS-133 UPDATES
- L2 STS-133 Special Section
- L2 Historical Section
- Click here to Join L2
The crew also deployed the SPARTAN-201 satellite, a free-flying science instrument platform designed to study velocity and acceleration of the solar wind and observe the sun’s corona. SPARTAN-201 free flew for two days before being retrieving by Discovery’s crew.
Upon return to Earth, Discovery was processed for STS-51 later that year. The initial launch attempt for STS-51 on July 17 was scrubbed due to the premature charging of the eight SRB hold down bolts and the ET GH2 (gaseous hydrogen) vent arm bolts. A circuit card in the pyrotechnic initiator controller was identified as the cause of the problem, and the card was replaced.
A subsequent launch attempt on July 24 was also scrubbed when problems with a hydraulic power unit on one of the SRBs arose. Launch was then rescheduled for mid-August to deconflict with the Perseid meteor shower.
The launch attempt on August 12 proceeded nominally through Main Engine ignition when, at T-3seconds, a RSLS abort was tripped by Discovery’s computers due to a faulty fuel flow sensor in one of the Main Engines.
This marked the 4th post-SSME start RSLS abort in Shuttle Program history and the second post-SSME start RSLS abort for orbiter Discovery. To this day, Discovery is the only Shuttle orbiter to have suffered two of these types of pad aborts.
Discovery and STS-51 was successfully launched on September 12, 1993 to deploy the Advanced Communications Technology Satellite (ACTS). Astronauts also performed one spacewalk during the mission to test tools and techniques that would be used on the STS-61 mission in December that year to save the Hubble Space Telescope which was found to have a vision problem after deployment from Discovery in 1990.
STS-51 also marked the first time a Shuttle mission flew with a GPS receiver. It would not be until August 2007 that a full 3-string GPS system would be used by the Shuttle fleet.
Discovery’s next mission would once again feature a first for the Shuttle Program: the first US/Russian Shuttle-MIR Program flight.
The mission, STS-60, carried the first Russian cosmonaut to fly on the Space Shuttle, and, while the mission did not dock to or come anywhere near the MIR space station, the mission did conduct the first bi-directional audio and downlink video hookup between the Shuttle and MIR.
However, STS-60 is more widely known for its SPACEHAB experiments and Wake Shield Facility experiment – which was conducted from the end of the SRMS (Shuttle Remote Manipulator System) after multiple attempts to deploy the experiment failed or were cancelled.
Later that year, Discovery flew the STS-64 mission, a flight that marked the first use of the Lidar In-space Technology Experiment and the first untethered US spacewalk in 10 years.
STS-64 also saw astronauts test a new SAFER device for EVA use. SAFERs are now a mandatory part of all EVAs (spacewalks) conducted by NASA.
Then, in February 1995, Discovery (STS-63) became the first Shuttle to carry a female pilot (Eileen Collins) and the first Shuttle orbiter to perform proximity ops with the Russian space station MIR. During the proximity ops, Discovery was maneuvered to within 11 meters distance of MIR.
STS-63 and Discovery paved the way for the start of joint Shuttle/MIR docked missions later that year. STS-63 also marked the 20th flight of orbiter Discovery.
Discovery’s 21st mission (STS-70) was then flown in July that year and deployed another TDRS satellite into Earth orbit, as well as conducted numerous scientific and medical experiments.
STS-70 further marked the first flight of a new Block I SSME, featuring new high-pressure liquid oxygen turbopumps, a two-duct powerhead, a baffleless main injector, a single-coil heat exchanger, and start sequence modifications – all designed to improve engine performance and safety.
Following this mission, Discovery was returned to Palmdale, CA for an Orbiter Modification Down Period, during which Discovery received a overhaul to prepare her for MIR and ISS mission operations.
Following the year-long procedure, Discovery was returned to the Kennedy Space Center in 1996 and prepared for her role on the 2nd Hubble Telescope servicing mission.
Launched on Feb. 11, 1997, STS-82 replaced the Goddard High Resolution Spectrograph and the Faint Object Spectrograph with the Space Telescope Imaging Spectrograph (STIS) and the Near Infrared Camera and Multi-Object Spectrometer, respectively.
Additionally, Hubble received a refurbished Fine Guidance Sensor, a replacement Solid State Recorder, and a new Reaction Wheel Assembly during Discovery’s visit.
Following STS-82, Discovery was processed for STS-85 in August 1997. This 12day mission performed numerous scientific experiments, with the primary payload being the Cryogenic Infrared Spectrometers and Telescopes for the Atmosphere-Shuttle Pallet Satellite-2.
Discovery then spent 10 months on the ground before taking flight again in June 1998 on STS-91 – a mission that marked the 9th and final docked Space Shuttle mission to the Russian MIR space station. The mission also represented Discovery’s first and only docking to MIR.
STS-91 also marked the first time that a Shuttle orbiter was launched with a Super Lightweight External Tank, which represented a 7,500lbs weight reduction to aid in payload upmass capability during construction flights to the soon-to-be International Space Station.
Discovery returned several long-term US experiments from MIR via the SPACEBAN single module during STS-91. Among further note for STS-91 is the flight of the prototype Alpha Magnetic Spectrometer (AMS) – a payload via AMS-2 that will be permanently attached to the International Space Station in 2011.
After this mission, Discovery was then called upon in October 1998 to fly what would be her last solo flight (meaning a mission that did not dock to Space Station or rendezvous with the Hubble Space Telescope).
Discovery was launched on STS-95 on Oct. 29 at 14:19:34 EDT. Onboard Discovery was then-US Senator John Glenn, who decades earlier had become the first American to orbit the Earth. During STS-95, Glenn became the oldest person ever to fly in space at the age of 77 – an honor he still holds today.
The nine day mission represented the 25th flight of orbiter Discovery and conducted several life-sciences experiments and validated future experiments for the Hubble Space Telescope. However, the mission is most notable (after John Glenn’s presence, that is) for the detachment of the Orbiter drag chute door seconds before liftoff.
While in orbit, NASA managers reviewed all necessary data and attempted to photograph this portion of Discovery using a military satellite, a procedure that proved fruitless. Eventually, it was determined that Discovery was safe to return to Earth; however, as a safety precaution, the crew was instructed not to deploy the drag chute upon landing.
Following completion of STS-95 on November 7, Discovery was processed for her first-ever ISS mission.
Launched on May 27, 1999 at 06:49 EDT, Discovery and STS-96 became the first Shuttle orbiter to dock with the ISS. The nine day mission delivered numerous supplies and outfitting equipment to the still unmanned orbital laboratory before concluding on June 3.
Discovery was then called upon in December 1999 to conduct the emergency HST-3A servicing mission following the failure of three of the Hubble Telescope’s six gyroscopes.
Four new gyroscopes were installed during the mission, as well as a new guidance sensor, a new computer, a voltage/temperature kit for the telescope’s batteries, a new transmitter, a solid state recorder, and new thermal insulation blankets.
After successfully completing the STS-103 mission to Hubble, Discovery was processed for mission STS-92. Launched on Oct. 11, 2000, the mission represented the 100th Space Shuttle flight in history and delivered the Z1 truss, Control Moment Gyros, Pressurized Mating Adaptor 3, and two DDCU heat pipes to the International Space Station.
Moreover, Discovery’s next flight, STS-102 in March 2001, delivered the 2nd permanent ISS crew to the space station and returned the 1st crew safely to Earth. The mission was also tasked with resupplying the ISS.
Discovery was then tasked with one more flight before entering another Orbiter Modification Down Period (OMDP). STS-105 was launched in August 2001. During the 12 day flight, Discovery rotated the Expedition 2 crew with the Expedition 3 crew and resupplied the ISS via the MPLM (Multi-Purpose Logistics Module) Leonardo.
STS-105 concluded with a touchdown at the Kennedy Space Center on August 22, after which Discovery was prepared for OMDP.
Sadly, it was during this OMDP that tragedy struck the Shuttle Program once more. On February 1, 2003, sister orbiter Columbia broke apart 207,000ft above Central Texas while reentering Earth’s atmosphere at the end of what had been the highly successful STS-107 microgravity scientific research mission.
The loss of Columbia grounded the Shuttle fleet (now only consisting of Discovery, Atlantis, and Endeavour) for two and one half years while engineers examined the cause of the Columbia accident and effected modifications to not only the External Tank’s TPS (Thermal Protection System) foam but also to the orbiters themselves.
Equipped with numerous safety upgrades including Wing Leading Edge Impact Detection sensors and an Orbiter Boom Sensor System (OBBS) to allow astronauts to scan the Wing Leading Edge RCC and nose cap panels, NASA enacted a wide-ranging safety upgrade on the orbiter fleet based on the recommendations from the Columbia Accident Investigation Board.
After two years of investigation, research, and safety implementation, NASA stood ready to return the Shuttle fleet to flight with the express purpose of completing construction and outfitting of the International Space Station by the congressionally mandated end date of September 30, 2010.
Initially, NASA’s Return to Flight (RTF) plans called for one Shuttle mission (designated STS-114) to carry out the RTF objectives; however, as those objectives and tests grew, a second RTF mission was added to the manifest, STS-121. Under the original plan, Atlantis was selected as the Return to Flight orbiter for STS-114, with Discovery taking up the all-important roll as Launch On Need rescue vehicle for STS-114 as well as the primary vehicle for STS-121.
This decision was reached in large part due to the fact that the follow up mission to STS-121, STS-115, was scheduled to deliver the P3/P4 truss and solar array structure to the ISS. The P3/P4 truss was too heavy to be launched by Discovery, leaving only Atlantis to fly that mission since Endeavour was still undergoing OMDP activities and was thus unavailable for mission duties.
However, a last-minute issue with an improperly installed gear in Atlantis’s braking system forced NASA to alter its plan and thereby hand Discovery the RTF STS-114 mission.
Initially rolled out to launch pad 39B on April 7, 2005 for a targeted May 2005 launch, a tanking test on Discovery and her External Tank on April 14 resulted in a LH2 (Liquid Hydrogen) Engine Cutoff (ECO) sensor anomaly – the sensors read as “dry” when there was hundreds of thousands of gallons of LH2 in the tank.
Subsequent analyses did not resolve the issue to the satisfaction of NASA managers and the decision was made to roll Discovery back to the VAB to swap stacks, placing Discovery on the originally intended STS-121 stack. Discovery was rolled back on May 26, demated on May 31, and mated to her new stack in early June.
