25-years ago today, Space Shuttle Challenger was lost with all hands in the bright blue sky over Central Florida. Embarking on her 10th mission on January 28, 1986, Challenger was at the time the most-flown orbiter in NASA’s fleet. Quickly rising to prominence as the fleet leader (in terms of not only the number of missions flown, but also her impressive scientific and technological accomplishments), Challenger was the workhorse of the early days of the Shuttle fleet, setting numerous records and leaving behind a legacy of education, inspiration, and safety.
The History of Space Shuttle Challenger:
The early history of Challenger is arguable the most complex of the six Shuttle orbiters (Enterprise, Columbia, Challenger, Discovery, Atlantis, and Endeavour) constructed by NASA in the 1970s, 80s, and 90s.
Beginning life as STA-099 (Structural Test Article -099), the components that would eventually become the airframe and body for orbiter Challenger were initially used by the Space Shuttle Program (SSP) to test and validate the effects of launch and entry stress (including heating) on a “light weight” Shuttle airframe – a weight reduction savings that would, in turn, allow future orbiters (from Challenger through Endeavour) to have a greater payload weight to orbit capability than pioneer orbiter and older sister Columbia.
Since computer technology in the 1970s was not powerful or advanced enough to accurately calculate/predict the effects a “light weight” airframe would have on an orbiter’s performance and ability during launch and entry ops, NASA opted to build STA-099 and submit the Structural Test Article to a year of intense vibration and thermal testing.
To this end, the contract to begin construction of STA-099 was awarded on July 26, 1972 to Rockwell International. For the next three years, components for STA-099 were manufactured simultaneously with components for what would eventually become orbiter Columbia.
STA-099’s tell-tale Delta wings arrived on-dock at the Palmdale, California construction facility on March 16, 1977.
Final assembly began later that year on September 30 and was completed on February 10, 1978. STA-099 rolled out of Palmdale on February 14 (Valentine’s Day), 1978.
For the next year, STA-099 was put through the wringer, with numerous vibration and thermal tests to provide and ground the light weight airframe design planned for future Shuttle orbiters.
As stated by Volume II of the NASA Engineering and Safety Center Technical Report from June 14, 2007, “There was a high probability that performing static strength tests to demonstrate ultimate design limits (1.4 times limit load) would result in deformations and strains that [would] render the vehicle unusable for flight.”
Nonetheless, “it was clear the vehicle must be shown to be acceptable at the design limit loads [ref. 19].”
To this end, “a hybrid qualification program was adopted that combined limited flight hardware testing and the validation of stress predictions through the modeling and testing of prototype hardware assemblies and components. “Qualification” tests on STA-099 were performed at 1.2 times the design limit loads.”
Meanwhile, Rockwell was busy finishing the final year of assembly of orbiter Columbia (OV-102) at Palmdale, and NASA was busy reviewing the wealth of data gathered from orbiter Enterprise’s (OV-101’s) free-flight approach and landing tests in 1977 while taking Enterprise through KSC mating, rollout, and launch pad validation ops.
But behind all this, discussions were beginning to focus on the cost and time that would be required to convert Enterprise into a space-worthy vehicle. As the costs and timelines began to build, NASA realized that it would cost less, and take less time, to convert STA-099 into a space-worthy vehicle than it would Enterprise.
On January 1, 1979, the decision was made official when NASA awarded Rockwell International the contract to convert STA-099 into OV-099 (Orbital Vehicle -099). While the process of converting STA-099 into OV-099 was simpler than converting Enterprise, it still involved intensive work and the disassembly and reconstruction of numerous air frame and flight elements.
With conversion of STA-099 into OV-099, the process began of selecting a name for the now-second orbiter of the Shuttle fleet.
Named after the HMS Challenger – a British corvette which served as the command ship for the Challenger Expedition (a pioneering global marine research expedition from 1872-1876) – and the Apollo 17 lunar module, Challenger is the only Shuttle orbiter to be named in honor of a previously-flown spacecraft that landed on the surface of another celestial body.
In an odd coincidence, crews began the start of structural assembly of Challenger’s flight-worthy crew module on January 28, 1979 – exactly 7 years to the day before she would be lost.
From this point, through Nov. 3, 1980, engineers and technicians disassembled and rebuilt Challenger. On Nov. 3, final assembly began and ran through October 21, 1981.
Workers spent the next year going over Challenger with a fine-toothed comb and completing installation of the vehicle’s Thermal Protection System (TPS) tiles and RCC (Reinforced Carbon-Carbon) WLE (Wing Leading Edge) and nose cap panels.
A major change between the construction of Columbia and Challenger was the replacement of TPS tiles with DuPont white nomex felt insulation on her payload bay doors, upper wing surfaces, and rear fuselage. This move further reduced Challenger’s weight by 2,500 lbs.
On June 30, 1982, Challenger rolled out of her Palmdale assembly facility. She was transported overland to Edwards Air Force Base the following day where she spent four days being mated to the Shuttle Carrier Aircraft for her ferry flight delivery to the Kennedy Space Center.
On the day of the beginning of the ferry flight, sister orbiter Columbia triumphantly returned to Earth on July 4 with an Independence Day landing at Edwards Air Force Base to cap off STS-4 and the orbital test flight phase of the Shuttle Program.
With Columbia on the runway at Edwards, Challenger and the SCA took off on July 4 under the watchful eye of then-U.S. President Ronald Reagan. One day later, Challenger arrived at the Kennedy Space Center.
One day after delivery, Challenger was towed into an OPF (Orbiter Processing Facility), where she underwent initial receiving inspections before being transitioned into pre-mission processing for her maiden flight.
Challenger spent nearly 4 months in the OPF before she was moved to the VAB on Nov. 23 for mating with her External Tank/Solid Rocket Booster (ET/SRB) stack. Seven days later, on November 30, 1982, Challenger and the STS-6 stack was rolled out to LC-39A to undergo both pad processing and the mandatory Flight Readiness Firing (FRF) before a targeted January 20, 1983 launch.
On December 18, 1982, the customary 20-second FRF occurred, revealing a hydrogen leak into SSME-1 (Space Shuttle Main Engine 1). Launch was postponed from January 20 and a second FRF was performed on January 25.
The second FRF confirmed the presence of cracks in SSME-1. To the end, all three SSMEs were removed while Challenger was at Pad-A. This marked the first time in Shuttle Program history that the SSMEs were removed at the launch pad.
The second FRF for Challenger also places her in the record books for being the only Shuttle orbiter to require two FRFs before her maiden flight. However, Challenger is not the only orbiter to have two FRFs to her name. Discovery underwent a second FRF during the Return to Flight launch campaign for STS-26 – the mission which returned the Shuttle fleet to flight following the loss of Challenger.
With the removal of all three of Challenger’s SSMEs, the teams thoroughly tested and analyzed SSMEs 2 and 3 before reinstalling them for flight. SSME-1 was completely replaced.
The launch date was then reset before being pushed back yet again due to the contamination of Challenger’s payload – the first Tracking and Data Relay Satellite (TDRS-1) – during a severe storm at the launch pad.
Once the contamination issue was fixed, the launch was rescheduled for April 4 at 1330 EST. The countdown proceeded on schedule and Challenger lifted off on her maiden voyage right on time on April 4, 1983.
Weighing 256,744lbs at launch, Challenger ushered in a series of firsts for the Shuttle Program STS-6. The maiden flight of Challenger marked the first flight of a Space Shuttle from the new MLP-2 (Mobile Launch Platform 2), the first Shuttle flight to use the Light Weight External Tank, the first flight of new light weight SRB casings, the first afternoon launch of a Space Shuttle, and the first time that a second reusable spacecraft flew into space.
On STS-6, Challenger carried Story Musgrave into space – the only person who would go to fly on all five space-worthy Space Shuttle orbiters.
STS-6 also marked the last time that a Space Shuttle mission would launch with a crew of only four astronauts. (However, if STS-135/Atlantis does indeed become a reality, STS-135 will mark the first time since STS-6 that a Shuttle will launch with only four people onboard.)
Launched into a 28.5 degree 178nm orbit, Challenger’s crew successfully deployed the TDRS-1 satellite from the vehicle’s payload bay. A malfunction of TDRS-1’s Inertial Upper Stage (IUS) initially placed the satellite into an improper but stable orbit. Reserve propellant was used to boost TDRS-1 into its properly circularized orbit over the following months.
Following the deployment of TDRS-1, the Challenger crew turned their attention to performing the Shuttle Program’s first spacewalk, or EVA. Lasting 4 hours 17 minutes, Mission Specialists Story Musgrave and Donald Peterson tested the Shuttle Program’s spacesuits, or EMUs, and demonstrated their ability to perform necessary tasks in a microgravity environment.
After 81 orbits of Earth and 2,094,293 miles, Challenger touched down on Runway 22 at Edwards Air Force Base, CA on April 9 at 10:53:42 PST, bringing her total mission duration for her maiden flight to 5 days 2 hours 14 minutes and 25 seconds.
Challenger then underwent initial post-flight deservicing at Edwards before returning to KSC on the SCA on April 16. She was towed into an OPF on April 17 to undergo post-flight deservicing and pre-flight mission processing for STS-7.
After just over a month in the OPF, Challenger was rolled over to the VAB on May 21 and mated to her ET/SRB stack for STS-7. The entire stack was rolled out to LC-39A on May 26 for a targeted June 18 launch.
Pad processing and the launch countdown proceeded nominal and Challenger lifted off right on time (with no launch delays) on her second flight at 07:33 EDT 18 June 1983. Launch of Challenger on STS-7 marked the first flight of an American woman in space and the first re-flight of an astronaut on the Space Shuttle – with Robert L. Crippen from STS-1 commanding Challenger’s second flight.
Launched into a 28.5 degree 160-170nm orbit, Challenger deployed two communications satellites (ANIK C-2 for Canada and PALAPA-B2) for Indonesia.
Seven Get Away Special canisters were also launched in Challenger’s payload bay, as well as an experiment studying the effects of space on the social behavior of an ant colony. Ten experiments were also mounted on Shuttle Pallet Satellite (SPAS-01), experiments designed to perform research in forming metal alloys in microgravity and the use of remote sensing scanners.
During the flight, Challenger’s crew fired the vehicle’s RCS control thrusters while SPAS-01 was held by SRMS (Shuttle Remote Manipulator System) to test the forces of the RCS firings on the extended arm.
STS-7 also marked the first time that a Shuttle orbiter’s Ku-Band antenna was used to transmit data through the TDRS network to a ground terminal.
STS-7 also holds the distinction of being the first Shuttle flight to carry a planned EOM (End of Mission) landing at the Kennedy Space Center; however, poor weather conditions at Kennedy precluded a landing of Challenger at the Florida spaceport.
The mission was extended by two orbits to help facilitate a landing at Edwards. Challenger successfully touched down on Runway 15 at Edwards at 06:56.59 PDT on June 24. Rollout distance was 10,450 feet over 75 seconds. Challenger was returned to the Kennedy Space Center on June 29 to begin processing for STS-8.
Challenger then spent June 30 – July 26 inside an OPF before rolling to the VAB for mating with the STS-8 SRB/ET stack. The entire vehicle was then rolled out to Pad-A on August 2 for an August 30 launch.
Initially, STS-8 had carried a July 1983 launch date for a 3-day 4-person mission to deploy the TDRS-B satellite. However, because of IUS issues during the deployment of TDRS-1, the flight was remanifested and TDRS-B pulled from the flight. (TDRS-B would later be remanifested for launch on Challenger’s STS-51E flight before additional problems with the satellite pushed its launch to the fateful STS-51L/Challenger mission.)
Pad processing for STS-8 was uneventful. In the early evening/night hours of Aug. 29/30, a large thunderstorm complex rolled over the Kennedy Space Center during the final few hours of the STS-8 countdown – providing a spectacular image of lightening arcing around Challenger as she sat on Pad-A.
Due to the inclement weather, launch was delayed 17 minutes. At 02:32 EDT, Challenger lit up the night sky of Florida, embarking on her third flight.
Launch of Challenger on STS-8 marked the first night time launch of the Space Shuttle, the 20th overall mission to launch from pad 39A, and the first flight of an African-American into space.
This would also become the first flight for which concern over potential catastrophic failure of the SRBs during flight would begin to build following discovery of SRB flight malfunction during post-flight casing inspections.
With a liftoff weight of 242,742 lbs, Challenger was inserted into 28.5 degree 191nm orbit. Over the course of the six day mission, Challenger’s crew deployed INSAT-1B for India and pointed the nose of Challenger away from the sun for a total of 14 hours to test the vehicle’s flight deck in extreme cold conditions.
During STS-8, Challenger’s orbit was lowered to 139nm to perform tests on thin atomic oxygen in an effort to understand the cause of a glow that had been observed to surround the orbiter during nighttime orbital passes.
Challenger’s SRMS was tested again on this mission to evaluate joint reactions to higher loads. Ku-Band testing/communication with TDRS-1 also continued on this flight to validate the system’s com connections before STS-9 made heavy use of TDRS-1.
Challenger also carried and tested equipment to allow for encrypted communications on future DoD (Department of Defense) dedicated and classified missions.
After 6 days 1 hour 8 minutes and 43 seconds, Challenger glided to a darkened Runway 22 at Edwards at 00:43:43 PDT on September 5 – thereby performing the first night time landing for the Space Shuttle Program.
Challenger was returned to the Kennedy Space Center on September 9 and moved into an OPF the following day. This time, Challenger spent four months in the OPF undergoing processing for the STS-41B flight. Just prior to OPF rollout, all three of Challenger’s Auxiliary Power Units (APUs) were removed and replaced (R&Red) as a precautionary measure following APU failures on Columbia’s STS-9 mission. As a result, the launch date for this mission was postponed from Jan. 29 to February 3.
On January 6, 1984, Challenger was finally rolled to the VAB. Six days later, the STS-41B stack was rolled out to Pad-A where processing occurred with just a few minor issues/hiccups.
Challenger lifted off right on time at 08:00 EST on February 3 on her fourth launch to begin the 10th Space Shuttle mission and the first under the new flight classification system. Had the previous numerical designation continued, this would have been the STS-11 mission.
(Incidentally, Challenger would be the first Shuttle orbiter to launch under the new classification system as well as the last orbiter to do so. NASA would revert back to the straight up numerical flight designation system following the loss of Challenger on STS-51L.)
Like her three previous missions, Challenger was inserted into a 28.5 degree 189nm orbit. Once in orbit, Challenger’s crew deployed the WESTAR-VI and PALAPA-B2 satellites and Bruce McCandless and Robert L. Stewart performed the first untethered EVA in history using the Manned Maneuvering Unit (McCandless) and the SRMS foot restraint for EVA purposes (Stewart). During this EVA, McCandless became the first human Earth-orbiting satellite when he ventured 320 feet away from Challenger.
Also carried aboard Challenger on this flight was the German-built Shuttle Pallet Satellite – which became the first satellite to be refurbished and re-flown into space following its first flight on STS-7. An electrical problem with SRMS, however, precluded the deployment of the satellite as intended.
After 7 days 23 hours 15 minutes and 55 seconds, Challenger triumphantly reentered Earth’s atmosphere to conduct the first EOM landing of a Space Shuttle at the Kennedy Space Center. Landing occurred on February 11 at 07:15:55 EST on KSC Runway 15. Rollout distance was 10,815 feet over 67 seconds.
Challenger was returned to the OPF later that day where she spent just over a month in pre-flight processing for STS-41C. On March 14, she was moved to the VAB. The STS-41C stack was rolled out to Pad-A on March 19 ahead of an April 6 launch.
Pad processing once again proceeded without issue, and on April 6, 1984 at 08:58 EST, Challenger lifted off right on time on her first attempt to begin her 5th mission.
The launch of STS-41C marked the first direct ascent trajectory for the Space Shuttle Program and the mission itself marked the first time that a Shuttle mission was on orbit on the anniversary of the first Space Shuttle flight (April 12).
Launched into a 28.5 degree 288nm high orbit, Challenger’s crew deployed the Long Duration Exposure Facility into Earth orbit for retrieval on a later Shuttle flight.
After this, Challenger’s orbit was raised to 313nm so that the crew could rendezvous, grapple, repair, and re-deploy the Solar Max satellite. Initial attempts by Mission Specialist George “Pinky” Nelson to manually grapple Solar Max with a special capture tool failed.
Nelson then tried to physically grab the satellite, but that sent the satellite into a multi-axis spin. In the overnight hours, the Goddard Spaceflight Center was able to regain control of the satellite. With the satellite stable, Challenger’s crew grappled the satellite with the SRMS and the crew turned their attention toward using the Manned Maneuvering Unit – tested on the previous flight – to replace the altitude control system and coronagraph/polarimeter electronics box in the Solar Max satellite.
The EVA activities were filmed by an IMAX camera in Challenger’s payload bay. The footage eventually became part of the “The Dream is Alive” documentary.
Challenger landed successfully on April 13 at 05:38:07 PST on Runway 17 at Edwards and was returned to the Kennedy Space Center on April 18. This would mark the final flight of the Shuttle with a fleet of only two orbiters. The next mission, STS-41D, would mark the addition of sister Discovery to the fleet.
However, due to lengthy delays with Discovery’s launch, Challenger ended up spending nearly five months in the OPF for STS-41G – the longest OPF stay for Challenger. On September 8, Challenger rolled to the VAB and out to Pad-A on September 13 ahead of a planned Oct. 5th launch.
Unlike all of Challenger’s previous missions, this flight was launched into a 57 degree 218nm orbit. The flight marked the first time a Shuttle carried a crew of seven into space, the first time two women flew into space together (and the first time two women were in space at the same time), the first time a Canadian flew into space, the first time an Australian-born person flew into space, and the first spacewalk to involve a woman.
During the 8-day flight, Challenger’s crew deployed the Earth Radiation Budget Satellite and, through an EVA, connected Components of Orbital Refueling System – thereby demonstrating that it was possible to refuel a satellite in orbit. During this EVA, Kathryn Sullivan became the first woman to perform a spacewalk.
On October 13, Challenger returned to Earth conducting the second landing of the Space Shuttle at the Kennedy Space Center. This flight would go down as Challenger’s longest mission, clocking in at 8 days 5 hours 23 minutes 33 seconds.
After four months in the OPF, Challenger was rolled over to the VAB on February 10 and then out to Pad-A on February 15. Initially, pad processing went smoothly until timing issues were encountered with TDRS-B.
The issues became severe enough that NASA pulled STS-51E from the launch manifest and cancelled the mission.
Challenger was rolled back from the launch pad on March 4, 1985 and returned to her OPF on March 7. NASA then remanifested Challenger for the STS-51B mission and OPF processing proceeded through April 10.
Challenger was mated to her STS-51B ET/SRB stack on April 10 and rolled out to Pad-A on April 15 ahead of a planned April 29 launch – only 14-days after Challenger arrived at the pad.
Pad processing proceeded smoothly. On April 29 a launch processing system failure forced a 2 minute 18 second delay to launch. At 12:02:18 EDT Challenger left Pad-A on her 7th flight and the Space Shuttle Program’s 17th.
Sadly, this was the second serious O-ring issue identified in 2.5 months. During the January 24, 1985 launch of Discovery/STS-51C, the primary O-rings in both the Right-Hand and Left-Hand SRBs were found to be severely charred. But it was the discovery of the complete burn-through/penetration of the primary O-ring and heavy charring and degradation of the secondary O-ring in the center field joint of the right STS-51C SRB that caused the greatest concern.
Investigations into the failure of the O-rings on STS-51C led to the understanding that the cold temperatures at the time of Discovery’s launch significantly reduced the sealing power of the O-rings. The temperature at the time of the 51C launch was 53 degrees F.
Sadly, both of these O-ring warnings would be ignored, and temperatures at the time of the 51L/Challenger launch one year later would be nearly 20 degrees colder than during 51C.
Nonetheless, Challenger successful obtained a 57 degree 222nm orbit for STS-51B, where she performed 15 primary experiments divided into five basic disciplines: materials sciences, life sciences, fluid mechanics, atmospheric physics, and astronomy via the European Spacelab-3 – flying here for the first time in a fully operational configuration.
Of the 15 primary experiments, 14 were deemed successful. Challenger landed successfully on May 6 at 09:11:04 PDT at Edwards.
After returning to the Kennedy Space Center, Challenger was in an OPF from May 12 – June 24, before being rolled to the VAB for mating and then out to Pad-A on June 29 ahead of a planned July 12 launch on STS-51F.
Pad processing proceeded nominally, as did the countdown. On July 12, the Ground Launch Sequencer handed off control of the countdown and Challenger’s critical systems to Challenger’s onboard computers at T-31secs.
At T-6.6 seconds, with all systems polling “go,” Challenger’s computers sent the commands to start the SSMEs in a 120-millisecond staggered start sequence beginning with SSME-3.
All three engines came up and began building up to full thrust.
At T-3seconds, Challenger’s computers registered a malfunction in SSME-2’s coolant valve and immediately tripped an RSLS (Redundant Set Launch Sequencer) abort. Commands to shut down SSME-2 were transmitted immediately, as were commands to inhibit the launch sequence, safe the SRB pyros, and shutdown SSMEs 3 and 1.
Thanks to the safety upgrades put in place following the STS-41D/Disocvery post-SSME start RSLS abort, post-abort safing was conducted in a methodical manner.
In the following two weeks, Challenger’s SSMEs were replaced at the launch pad and the launch was reset for July 29, 1985.
On that day, the launch was delayed 1 hour 37 minutes due to a problem with the table maintenance block update uplink. With that issue resolved, the countdown resumed and Challenger launched at 17:00 EDT on her 8th mission.
However, 3mins 13secs into the flight, one of two high pressure fuel turbopump turbine discharge temperature sensors for SSME-1 failed, leaving only one sensor active on the engine. Two minutes 12 seconds later, at Mission Elapsed Time 5mins 43secs, the second sensor failed, triggering the immediate shutdown of SSME-1.
To date, this is the only occurrence of an engine shutdown during launch for the Space Shuttle.
The shutdown of SSME-1 significantly lowered the thrust profile for Challenger and triggered the only in-flight abort in Shuttle Program history: an Abort To Orbit (ATO) which allowed Challenger and her seven-member crew to reach a lower-than-planned but safe and stable orbit.
Nonetheless, before Challenger could complete her prolonged ascent (nearly 9mins 45secs in duration due to the lost thrust from SSME-1), an identical high pressure turbopump temperature sensor failure occurred in SSME-2.
Booster Systems Engineer Jenny M. Howard in Mission Control Houston acted immediately, instructing the crew to inhibit any further automatic SSME shutdowns based on readings from the remaining sensors. This quick action prevented the loss of another engine and a possible abort scenario far more risky or far worse than the already in-progress ATO.
The flight’s primary payload was Spacelab-2, with the main mission objectives being the verification of performance of Spacelab systems and the determination of interface capability of the Shuttle orbiter.
STS-51F marked the first time the European Space Agency’s Instrument Point System was tested in orbit… with verification of its accuracy to one arc second.
After 7 days 22 hours 45 minutes and 26 seconds in space, Challenger touched down on Runway 23 at Edwards at 12:45:26 EDT on August 6. She was returned to the Kennedy Space Center on August 11.
Challenger then spent exactly 2 months in the OPF while processing for STS-61A, before rolling to the VAB on Oct. 12. The STS-61A stack was rolled out to Pad-A on Oct. 16 for an October 30 launch.
Yet again, pad processing proceeded nominally and Challenger lifted off right on time on her first attempt at 12-noon EST on October 30.
Launch of STS-61A marked the 22nd flight of the Space Shuttle, the 9th flight of Challenger, and the first and only time in history when eight people launched into space at the same time on the same vehicle.
Launched into a 57 degree 207nm orbit, Challenger’s flight was dedicated entirely to the German Spacelab (D-1) mission. The Spacelab mission encompassed 75 numbered experiments, most of which were performed more than once.
While Challenger herself was controlled through Mission Control Houston, the scientific operations were controlled from the German Space Operations Center at Oberpfaffenhofen, near Munich
Challenger glided back to Earth on November 6, landing on Runway 17 at Edwards at 09:44:51 PST. Rollout distance was 8,304 feet over 49 seconds.
Challenger was returned to the Kennedy Space Center on November 11, where she began processing for the long-awaited and much anticipated STS-51L mission.
Spending just over a month in the OPF, Challenger was rolled to the VAB on December 16 for mating with her ET and SRB stack.
The entire STS-51L stack was moved to Launch Complex 39B on December 22, 1985. With the rollout of Challenger to Pad-B, it marked the first time a Space Shuttle orbiter graced Pad-B as well as the first of 19 times in SSP history when both Shuttle launch pads at Kennedy were occupied simultaneously. (Columbia was on Pad-A following the mounting delays to her STS-61C mission).
When Challenger arrived at Pad-B, her primary payload, the TDRS-B satellite was loaded into her payload bay, and processing continued toward a targeted launch date of January 22, 1986 at 15:43 EST.
However, due to delays to the STS-61C mission, the launch date was slipped to the January 23, then 24th.
The launch was then moved again to January 25 due to unacceptable weather conditions at the mission’s Transoceanic Abort Landing (TAL) site in Dakar, Senegal. The decision was then made to utilize Casablanca as an alternate TAL site. However, since Casablanca was not equiped to handle a night landing, the launch time on January 25 was moved to the morning.
The launch was then quickly delayed again to January 26 when ground teams were unable to meet the new target launch time. The forecast for unacceptable launch site weather on January 26 then prompted launch personnel to move the launch to January 27.
The weather on January 26 would have been more than acceptable for launch.
On January 27, Challenger’s flight crew boarded the vehicle and all appeared to be going well, with the only concern being winds at the Shuttle Landing Facility (SLF).
However, when the closeout crew went to close and lock Challenger’s hatch for flight, they were unable to remove the locking tool from the hatch. Numerous attempts to the remove the tool failed. Eventually, a saw was delivered to Pad-B and the tool sawed off and the attaching bolt drilled out.
The closeout crew then continued and finished closeout operations. However, during the delay caused by this issue, crosswinds at the SLF exceed RTLS (Return to Launch Site) abort limits and the launch was scrubbed for 24hrs.
In the overnight hours, temperatures at the launch pad dropped into the teens (degrees F). Water pipes at the launch pad were opened to prevent them from freezing and bursting, thus creating icicles of significant length on the launch pad structure.
Fueling of Challenger’s External Tank began in the early morning hours. Launch was delayed by two hours when the hardware interface module in the launch processing system, which monitors fire detection systems, failed during liquid hydrogen loading.
With the resolution of this issue and Challenger’s ET fully fueled, Challenger’s flight crew – Commander Francis R. Scobee, Pilot Michael J. Smith, Mission Specialist 1 (MS 1) Judith A. Resnik, MS2/Flight Engineer Ellison Onizuka, MS3 Ronald E. McNair, Payload Specialist 1 (PS 1) Gregory B. Jarvis, and PS2 Sharon Christa McAuliffe – once again boarded Challenger.
Final polls were conducted and all stations polled “go” for launch.
Challenger executed a 90-degree roll off Pad-B, to place her onto the proper alignment for a 28.5 degree inclination orbit, and climbed quickly and gracefully into the crystal clear Florida sky.
At 11:39:13 EST on January 28, 1986, the Space Shuttle Challenger and her seven member crew slipped from view.
Addressing a grieving and disheartened nation that night, President Ronald Reagan stated: “Today is a day for mourning and remembering. Nancy and I are pained to the core by the tragedy of the shuttle Challenger. We know we share this pain with all of the people of our country. This is truly a national loss.
“And perhaps we’ve forgotten the courage it took for the crew of the shuttle. But they, the Challenger Seven, were aware of the dangers, but overcame them and did their jobs brilliantly. We mourn seven heroes: Michael Smith, Dick Scobee, Judith Resnik, Ronald McNair, Ellison Onizuka, Gregory Jarvis, and Christa McAuliffe.
“For the families of the seven, we cannot bear, as you do, the full impact of this tragedy. But we feel the loss, and we’re thinking about you so very much. Your loved ones were daring and brave, and they had that special grace, that special spirit that says, ‘Give me a challenge, and I’ll meet it with joy.’ They had a hunger to explore the universe and discover its truths. They wished to serve, and they did. They served all of us.
“We’ve grown used to wonders in this century. It’s hard to dazzle us. But for twenty-five years the United States space program has been doing just that. We’ve grown used to the idea of space, and, perhaps we forget that we’ve only just begun. We’re still pioneers. They, the members of the Challenger crew, were pioneers.
“And I want to say something to the schoolchildren of America who were watching the live coverage of the shuttle’s take-off. I know it’s hard to understand, but sometimes painful things like this happen. It’s all part of the process of exploration and discovery. It’s all part of taking a chance and expanding man’s horizons. The future doesn’t belong to the fainthearted; it belongs to the brave. The Challenger crew was pulling us into the future, and we’ll continue to follow them.
“I’ve always had great faith in and respect for our space program. And what happened today does nothing to diminish it. We don’t hide our space program. We don’t keep secrets and cover things up. We do it all up front and in public. That’s the way freedom is, and we wouldn’t change it for a minute.
“We’ll continue our quest in space. There will be more shuttle flights and more shuttle crews and, yes, more volunteers, more civilians, more teachers in space. Nothing ends here; our hopes and our journeys continue.
“I want to add that I wish I could talk to every man and woman who works for NASA, or who worked on this mission and tell them: ‘Your dedication and professionalism have moved and impressed us for decades. And we know of your anguish. We share it.’
“There’s a coincidence today. On this day three hundred and ninety years ago, the great explorer Sir Francis Drake died aboard ship off the coast of Panama. In his lifetime the great frontiers were the oceans, and a historian later said, ‘He lived by the sea, died on it, and was buried in it.’ Well, today, we can say of the Challenger crew: Their dedication was, like Drake’s, complete.
“The crew of the space shuttle Challenger honored us by the manner in which they lived their lives. We will never forget them, nor the last time we saw them, this morning, as they prepared for their journey and waved goodbye and ‘slipped the surly bonds of earth to ‘touch the face of God.'”
During the course of the planned 6 day mission, Challenger’s crew would have deployed TDRS-B on Flight Day 1 (FD 1).
On Flight Day 2, the Comet Halley Active Monitoring Program (CHAMP) experiment was scheduled to begin. Also scheduled were the initial “teacher in space” video tapings. A firing of the OMS engines to place Challenger at the 152-mile orbital altitude from which the Spartan satellite would be deployed was also scheduled.
On Flight Day 3, the crew was to begin pre-deployment preparations on Spartan before deploying the satellite using the SRMS.
On Flight Day 4, the Challenger was to begin closing on Spartan while Gregory B. Jarvis continued fluid dynamics experiments started on FD-2 and FD-3. Live telecasts were also planned to be conducted by Christa McAuliffe.
On Flight Day 5, the crew was to rendezvous with Spartan and use the SRMS to capture the satellite and re-stow it in the payload bay.
On Flight Day 6, re-entry preparations were scheduled, followed on FD-7 by reentry and landing at the Kennedy Space Center.
Yet, Challenger’s mission objectives – deploying TDRS-B and flying a teaching in space – would be carried our by her sisters. TDRS-B’s replacement was deployed by Discovery during the STS-26 Return to Flight mission in September 1988.
But perhaps most fitting, school teacher Barbara Morgan, Christa McAuliffe’s backup, would realize her and Christa’s dream on August 8, 2007 when she launched as a full Mission Specialist on Space Shuttle Endeavour’s – Challenger’s replacement – STS-118 mission to the International Space Station.
In all, Space Shuttle Challenger deployed 10 satellites in her 10 mission career. She spent a total of 62 days 7 hours 56 minutes and 22 seconds in space, travelling 25,803,936 miles in 995 orbits of Earth.
And as we pause today to remember the Challenger crew, it is of great importance to remember the cause for which they freely served: the pursuit of scientific knowledge, education, and understanding. This is the cause for which we continue to fly, and cause for which we can never forget.
(All Images via L2 Historical and NASA.gov)