Misplaced Pages

Space Shuttle Challenger disaster

Article snapshot taken from Wikipedia with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.
#441558

111-567: On January 28, 1986, the Space Shuttle Challenger broke apart 73 seconds into its flight, killing all seven crew members aboard. The spacecraft disintegrated 46,000 feet (14 km) above the Atlantic Ocean, off the coast of Cape Canaveral , Florida, at 11:39   a.m. EST (16:39   UTC ). It was the first fatal accident involving an American spacecraft while in flight. The mission, designated STS-51-L ,

222-497: A catastrophic structural failure and explosion of the External Tank . The resulting pressure waves and aerodynamic forces destroyed the orbiter, resulting in the loss of all of the crew. Challenger was the first Space Shuttle to be destroyed in a mission disaster. The collected debris of the vessel is currently buried in decommissioned missile silos at Launch Complex 31 , Cape Canaveral Air Force Station . A section of

333-519: A crewed orbiter. To replace Challenger , the construction of a new Space Shuttle orbiter, Endeavour , was approved in 1987, and the new orbiter first flew in 1992. Subsequent missions were launched with redesigned SRBs and their crews wore pressurized suits during ascent and reentry . The Space Shuttle was a partially reusable spacecraft operated by the US National Aeronautics and Space Administration (NASA). It flew for

444-555: A double bore seal, and the gap between segments was filled with putty. When the motor was running, this configuration was designed to compress air in the gap against the upper O-ring, pressing it against the sealing surfaces of its seat. On the SRB Critical Items List, the O-rings were listed as Criticality 1R, which indicated that an O-ring failure could result in the destruction of the vehicle and loss of life, but it

555-436: A force equating to roughly 3,000,000 pounds-force (13 meganewtons), while the right SRB collided with the intertank structure. These events resulted in an abrupt change to the shuttle stack's attitude and direction, which was shrouded from view by the vaporized contents of the now-destroyed ET. As it traveled at Mach 1.92, Challenger took aerodynamic forces it was not designed to withstand and broke into several large pieces:

666-439: A glass of cold water and a piece of rubber, for which he received media attention. Feynman, a Nobel Prize -winning physicist, advocated for harsher criticism towards NASA in the report and repeatedly disagreed with Rogers. He threatened to remove his name from the report unless it included his personal observations on reliability, which appeared as Appendix F. In the appendix, he lauded the engineering and software accomplishments in

777-597: A life support system, and most of the cockpit instrumentation. Modifying it for spaceflight was considered to be too difficult, expensive, and time-consuming. Since STA-099 was not as far along in the construction of its airframe, it would be easier to upgrade to a flight article. Because STA-099's qualification testing prevented damage, NASA found that rebuilding STA-099 into a flightworthy orbiter would be less expensive than refitting Enterprise . Work on converting STA-099 to operational status began in January 1979, starting with

888-475: A post-flight inspection of the left SRB on STS-41-D revealed that soot had blown past the primary O-ring and was found in between the O-rings. Although there was no damage to the secondary O-ring, this indicated that the primary O-ring was not creating a reliable seal and was allowing hot gas to pass. The amount of O-ring erosion was insufficient to prevent the O-ring from sealing, and investigators concluded that

999-623: A potentially catastrophic flaw in the SRBs' O-rings, but neither NASA nor SRB manufacturer Morton Thiokol had addressed this known defect. NASA managers also disregarded engineers' warnings about the dangers of launching in cold temperatures and did not report these technical concerns to their superiors. As a result of this disaster, NASA established the Office of Safety, Reliability, and Quality Assurance, and arranged for deployment of commercial satellites from expendable launch vehicles rather than from

1110-405: A redesigned field joint that introduced a metal lip to limit movement in the joint. They also recommended adding a spacer to provide additional thermal protection and using an O-ring with a larger cross section. In July   1985, Morton Thiokol ordered redesigned SRB casings, with the intention of using already-manufactured casings for the upcoming launches until the redesigned cases were available

1221-425: A report on the deaths of the crew from physician and Skylab 2 astronaut Joseph P. Kerwin : The findings are inconclusive. The impact of the crew compartment with the ocean surface was so violent that evidence of damage occurring in the seconds which followed the disintegration was masked. Our final conclusions are: Pressurization could have enabled consciousness for the entire fall until impact. The crew cabin hit

SECTION 10

#1732772769442

1332-523: A risk management review for all critical systems. Space Shuttle Challenger Space Shuttle Challenger ( OV-099 ) was a Space Shuttle orbiter manufactured by Rockwell International and operated by NASA . Named after the commanding ship of a nineteenth-century scientific expedition that traveled the world, Challenger was the second Space Shuttle orbiter to fly into space after Columbia , and launched on its maiden flight in April 1983. It

1443-519: A tang from the upper segment fitting into the clevis of the lower segment. Each field joint was sealed with two ~20 foot (6 meter) diameter Viton-rubber O-rings around the circumference of the SRB and had a cross-section diameter of 0.280 inches (7.1 mm). The O-rings were required to contain the hot, high-pressure gases produced by the burning solid propellant and allowed for the SRBs to be rated for crewed missions. The two O-rings were configured to create

1554-488: A wing, the (still firing) main engines, the crew cabin and hypergolic fuel leaking from the ruptured reaction control system were among the parts identified exiting the vapor cloud. The disaster unfolded at an altitude of 46,000 feet (14 km). Both SRBs survived the breakup of the shuttle stack and continued flying, now unguided by the attitude and trajectory control of their mothership, until their flight termination systems were activated at T+110 . At T+73.191 , there

1665-514: Is estimated to have been between 12 and 20 times that of gravity ( g ). Within two seconds it had dropped below 4   g, and within ten seconds the cabin was in free fall . The forces involved at this stage were probably insufficient to cause major injury to the crew. At least some of the crew were alive and conscious after the breakup, as Personal Egress Air Packs (PEAPs) were activated for Smith and two unidentified crewmembers, but not for Scobee. The PEAPs were not intended for in-flight use, and

1776-451: Is the only flight to have both launched and landed with a crew of eight, and STS-71 in 1995 is the only other flight to have landed with a crew of eight. * Note 1: In this year, Approach and Landing Tests (ALT) were accomplished. These were atmospheric only, non-spaceflight tests from a Boeing 747 Shuttle Carrier Aircraft , both with the orbiter attached and for a series of drop-test flights. ** Note 2: The durations listed count only

1887-697: The Atlantic Ocean under a parachute. NASA retrieval teams recovered the SRBs and returned them to the Kennedy Space Center (KSC), where they were disassembled and their components were reused on future flights. Each SRB was constructed in four main sections at the factory in Utah and transported to KSC, then assembled in the Vehicle Assembly Building at KSC with three tang-and-clevis field joints, each joint consisting of

1998-529: The Challenger accident was the result of poor communications and overly complicated explanations on the part of engineers, and stated that showing the correlation of ambient air temperature and O-ring erosion amounts would have been sufficient to communicate the potential dangers of the cold-weather launch. Boisjoly contested this assertion and stated that the data presented by Tufte were not as simple or available as Tufte stated. The Presidential Commission on

2109-534: The Johnson Space Center (JSC) who advised him that ice did not threaten the safety of the orbiter, and he decided to proceed with the launch. The launch was delayed for an additional hour to allow more ice to melt. The ice team performed an inspection at T–20 minutes which indicated that the ice was melting, and Challenger was cleared to launch at 11:38 a.m. EST, with an air temperature of 36 °F (2 °C). At T+0, Challenger launched from

2220-558: The Kennedy Space Center Launch Complex 39B (LC-39B) at 11:38:00   a.m. Beginning at T+0.678 until T+3.375 seconds, nine puffs of dark gray smoke were recorded escaping from the right-hand SRB near the aft strut that attached the booster to the ET . It was later determined that these smoke puffs were caused by joint rotation in the aft field joint of the right-hand SRB at ignition. The cold temperature in

2331-495: The Launch Commit Criteria . In addition to its effect on the O-rings, the cold temperatures caused ice to form on the fixed service structure . To keep pipes from freezing, water was slowly run from the system; it could not be entirely drained because of the upcoming launch. As a result, ice formed from 240 feet (73 m) down in the freezing temperatures. Engineers at Rockwell International , which manufactured

SECTION 20

#1732772769442

2442-807: The National Aeronautics and Space Administration . List of Space Shuttle crews This is a list of persons who served aboard Space Shuttle crews , arranged in chronological order by Space Shuttle missions. Abbreviations: Names of astronauts returning from the Mir or ISS on the Space Shuttle are shown in italics . They did not have specific crew roles, but are listed in the Payload Specialist columns for reasons of space. Only two flights have carried more than seven crew members for either launch or landing. STS-61-A in 1985

2553-776: The Pacific Ocean . Unidentified crew remains were buried at the Space Shuttle Challenger Memorial in Arlington on May 20, 1986. President Ronald Reagan had been scheduled to give the 1986 State of the Union Address on January   28,   1986, the evening of the Challenger disaster. After a discussion with his aides, Reagan postponed the State of the Union, and instead addressed

2664-476: The Space Shuttle program . Challenger (OV-099) was the second orbiter constructed after its conversion from a structural test article . The orbiter contained the crew compartment, where the crew predominantly lived and worked throughout a mission. Three Space Shuttle main engines (SSMEs) were mounted at the aft end of the orbiter and provided thrust during launch. Once in space, the crew maneuvered using

2775-850: The death certificates ; NASA officials ultimately released the death certificates of the crew members. The IUS that would have been used to boost the orbit of the TDRS-B satellite was one of the first pieces of debris recovered. There was no indication that there had been premature ignition of the IUS, which had been one of the suspected causes for the disaster. Debris from the three SSMEs was recovered from February   14 to   28, and post-recovery analysis produced results consistent with functional engines suddenly losing their LH2 fuel supply. Deepwater recovery operations continued until April   29, with smaller scale, shallow recovery operations continuing until August   29. On December 17, 1996, two pieces of

2886-442: The first German crewed spaceflight mission . Passengers carried into orbit by Challenger include the first American female astronaut , the first American female spacewalker , the first African-American astronaut , and the first Canadian astronaut . On its tenth flight in January 1986, Challenger broke up 73 seconds after liftoff, killing the seven-member crew of STS-51-L that included Christa McAuliffe , who would have been

2997-407: The first teacher in space . The Rogers Commission concluded that an O-ring seal in one of Challenger ' s solid rocket boosters failed to contain pressurized burning gas that leaked out of the booster, causing a structural failure of Challenger ' s external tank and the orbiter's subsequent breakup due to aerodynamic forces . NASA's organizational culture was also scrutinized by

3108-412: The range safety officer destroyed them. The crew compartment, human remains, and many other fragments from the shuttle were recovered from the ocean floor after a three-month search-and-recovery operation. The exact timing of the deaths of the crew is unknown, but several crew members are thought to have survived the initial breakup of the spacecraft. The orbiter had no escape system , and the impact of

3219-523: The 196,726 lb (89,233 kg) of both SRB shells, 102,500 lb (46,500 kg) was recovered, another 54,000 lb (24,000 kg) was found but not recovered, and 40,226 lb (18,246 kg) was never found. On March 7, Air Force divers identified potential crew compartment debris, which was confirmed the next day by divers from the USS Preserver . The damage to the crew compartment indicated that it had remained largely intact during

3330-578: The Centaur to study the polar regions of the Sun. Challenger flew the first American woman , African-American , Dutchman , and Canadian into space; carried three Spacelab missions; and performed the first night launch and night landing of a Space Shuttle. STS-51-L was the orbiter's tenth and final flight, initially planned to launch on January 26, 1986 (after several technical and paperwork delays). The mission attracted huge media attention, as one of

3441-531: The ET, causing lateral acceleration that was felt by the crew. At the same time, pressure in the LH2 tank began dropping. Pilot Mike Smith said "Uh-oh," which was the last crew comment recorded. At T+73.124 , white vapor was seen flowing away from the ET, after which the aft dome of the LH2 tank fell off. The resulting release of all liquid hydrogen in the tank pushed the LH2 tank forward into the liquid oxygen (LOX) tank with

Space Shuttle Challenger disaster - Misplaced Pages Continue

3552-511: The Moon in 1972, was also named Challenger . Because of the low production volume of orbiters, the Space Shuttle program decided to build a vehicle as a Structural Test Article , STA-099, that could later be converted to a flight vehicle. The contract for STA-099 was awarded to North American Rockwell on July 26, 1972, and construction was completed in February 1978. After STA-099's rollout, it

3663-583: The NASA Verification/Certification Committee requested further tests on joint integrity to include testing in the temperature range of 40 to 90 °F (4 to 32 °C) and with only a single O-ring installed. The NASA program managers decided that their current level of testing was sufficient and further testing was not required. In December   1982, the Critical Items List was updated to indicate that

3774-527: The NASA accident investigation, the Space Shuttle program, and the Morton Thiokol recommendation to launch despite O-ring safety issues. On February   15, Rogers released a statement that established the commission's changing role to investigate the accident independent of NASA due to concerns of the failures of the internal processes at NASA. The commission created four investigative panels to research

3885-441: The NASA administrator to oversee all safety, reliability, and quality assurance functions in NASA programs. Additionally, the commission addressed issues with overall safety and maintenance for the orbiter, and it recommended the addition of the means for the crew to escape during controlled gliding flight. During a televised hearing on February   11, Feynman demonstrated the loss of rubber's elasticity in cold temperatures using

3996-680: The O-rings would seal at temperatures colder than 53 °F (12 °C), the coldest launch of the Space Shuttle to date. Morton Thiokol employees Robert Lund, the Vice President of Engineering, and Joe Kilminster, the Vice President of the Space Booster Programs, recommended against launching until the temperature was above 53 °F (12 °C). The teleconference held a recess to allow for private discussion amongst Morton Thiokol management. When it resumed, Morton Thiokol leadership had changed their opinion and stated that

4107-651: The Rogers Commission, and the Space Shuttle program's goal of replacing the United States' expendable launch systems was cast into doubt. The loss of Challenger and its crew led to a broad rescope of the program, and numerous aspects – such as launches from Vandenberg , the MMU, and Shuttle-Centaur – were scrapped to improve crew safety; Challenger and Atlantis were the only orbiters modified to conduct Shuttle-Centaur launches. The recovered remains of

4218-538: The SRBs were kept wet during recovery, and their unused propellant was ignited once they were brought ashore. The failed joint on the right SRB was first located on sonar on March   1. Subsequent dives to 560 ft (170 m) by the NR-1 submarine on April   5 and the SEA-LINK I submersible on April   12 confirmed that it was the damaged field joint, and it was successfully recovered on April   13. Of

4329-525: The Space Shuttle Challenger Accident, also known as the Rogers Commission after its chairman, was formed on February   6. Its members were Chairman William P. Rogers , Vice Chairman Neil Armstrong , David Acheson , Eugene Covert , Richard Feynman , Robert Hotz, Donald Kutyna , Sally Ride , Robert Rummel, Joseph Sutter , Arthur Walker , Albert Wheelon, and Chuck Yeager . The commission held hearings that discussed

4440-534: The Sun, and deploy and retrieve a SPARTAN satellite. The mission was originally scheduled for July   1985, but was delayed to November and then to January   1986. The mission was scheduled to launch on January   22, but was delayed until January 28. The air temperature on January 28 was predicted to be a record low for a Space Shuttle launch. The air temperature was forecast to drop to 18 °F (−8 °C) overnight before rising to 22 °F (−6 °C) at 6:00   a.m. and 26 °F (−3 °C) at

4551-411: The United States. The cause of the disaster was the failure of the primary and secondary O-ring seals in a joint in the shuttle's right solid rocket booster (SRB). The record-low temperatures on the morning of the launch had stiffened the rubber O-rings, reducing their ability to seal the joints. Shortly after liftoff, the seals were breached, and hot pressurized gas from within the SRB leaked through

Space Shuttle Challenger disaster - Misplaced Pages Continue

4662-506: The accident, paid 60 percent, or $ 4,641,000. The remainder, $ 3,094,000, was paid by the government. In September 1988 a federal judge dismissed two lawsuits seeking $ 3 billion from Space Shuttle rocket-maker Morton Thiokol Inc. by Roger Boisjoly , a former company engineer who warned against the ill-fated 1986 Challenger launch. * Mission canceled due to loss of Challenger on STS-51-L . [REDACTED]  This article incorporates public domain material from websites or documents of

4773-402: The aft attach strut on the right SRB, right before the vehicle passed through max q at T+59.000 . The high aerodynamic forces and wind shear likely broke the aluminum oxide seal that had replaced eroded O-rings, allowing the flame to burn through the joint. Within one second from when it was first recorded, the plume became well-defined, and the enlarging hole caused a drop in internal pressure in

4884-605: The amount of training, quality control, and repair work that was available for each mission. The commission published a series of recommendations to improve the safety of the Space Shuttle program. It proposed a redesign of the joints in the SRB that would prevent gas from blowing past the O-rings. It also recommended that the program's management be restructured to keep project managers from being pressured to adhere to unsafe organizational deadlines, and should include astronauts to address crew safety concerns better. It proposed that an office for safety be established reporting directly to

4995-589: The astronauts never trained with them for an in-flight emergency. The location of Smith's activation switch, on the back side of his seat, indicated that either Resnik or Onizuka likely activated it for him. Investigators found their remaining unused air supply consistent with the expected consumption during the post-breakup trajectory. While analyzing the wreckage, investigators discovered that several electrical system switches on Smith's right-hand panel had been moved from their usual launch positions. The switches had lever locks on top of them that must be pulled out before

5106-525: The astronauts' remains were transferred on a C-141 Starlifter aircraft from Kennedy Space Center to the military mortuary at Dover Air Force Base in Delaware . Their caskets were each draped with an American flag and carried past an honor guard and followed by an astronaut escort. After the remains arrived at Dover Air Force Base, they were transferred to the families of the crew members. Scobee and Smith were buried at Arlington National Cemetery . Onizuka

5217-480: The atmosphere, where it would break apart during reentry and its pieces would land in the Indian or Pacific Ocean . Two solid rocket boosters (SRBs), built by Morton Thiokol at the time of the disaster, provided the majority of thrust at liftoff. They were connected to the external tank, and burned for the first two minutes of flight. The SRBs separated from the orbiter once they had expended their fuel and fell into

5328-460: The cause of the accident was hot gas blowing past the O-rings in the field joint on the right SRB, and found no other potential causes for the disaster. It attributed the accident to a faulty design of the field joint that was unacceptably sensitive to changes in temperature, dynamic loading, and the character of its materials. The report was critical of NASA and Morton Thiokol, and emphasized that both organizations had overlooked evidence that indicated

5439-485: The cold temperatures caused a loss of flexibility in the O-rings that decreased their ability to seal the field joints, which allowed hot gas and soot to flow past the primary O-ring. O-ring erosion occurred on all but one ( STS-51-J ) of the Space Shuttle flights in 1985, and erosion of both the primary and secondary O-rings occurred on STS-51-B . To correct the issues with O-ring erosion, engineers at Morton Thiokol, led by Allan McDonald and Roger Boisjoly , proposed

5550-785: The conversion until July 1982, when the new orbiter was rolled out as Challenger . Challenger , as did the orbiters built after it, had fewer tiles in its Thermal Protection System than Columbia , though it still made heavier use of the white LRSI tiles on the cabin and main fuselage than did the later orbiters. Most of the tiles on the payload bay doors, upper wing surfaces, and rear fuselage surfaces were replaced with DuPont white Nomex felt insulation. These modifications and an overall lighter structure allowed Challenger to carry 2,500 lb (1,100 kg) more payload than Columbia. Challenger ' s fuselage and wings were stronger and lighter than Columbia ' s. The hatch and vertical-stabilizer tile patterns were different from those of

5661-491: The crew compartment at terminal velocity with the ocean surface was too violent to be survivable. The disaster resulted in a 32-month hiatus in the Space Shuttle program . President Ronald Reagan created the Rogers Commission to investigate the accident. The commission criticized NASA 's organizational culture and decision-making processes that had contributed to the accident. Test data since 1977 demonstrated

SECTION 50

#1732772769442

5772-660: The crew module (the pressurized portion of the vehicle), as the rest of the vehicle was still being used for testing by Lockheed. STA-099 returned to the Rockwell plant in November 1979, and the original, unfinished crew module was replaced with the newly constructed model. Major parts of STA-099, including the payload bay doors, body flap, wings, and vertical stabilizer, also had to be returned to their individual subcontractors for rework. By early 1981, most of these components had returned to Palmdale to be reinstalled. Work continued on

5883-563: The crew was a civilian schoolteacher, Christa McAuliffe , who was assigned to carry out live lessons from the orbiter (as part of NASA's Teacher in Space Project ). Other members would deploy the TDRS-B satellite and conduct comet observations. Challenger blasted off at 11:38 am EST on January 28, 1986. Just over a minute into the flight, a faulty booster joint opened up, leading to a flame that melted securing struts which resulted in

5994-521: The different aspects of the mission. The Accident Analysis Panel, chaired by Kutyna, used data from salvage operations and testing to determine the exact cause behind the accident. The Development and Production Panel, chaired by Sutter, investigated the hardware contractors and how they interacted with NASA. The Pre-Launch Activities Panel, chaired by Acheson, focused on the final assembly processes and pre-launch activities conducted at KSC. The Mission Planning and Operations Panel, chaired by Ride, investigated

6105-541: The disaster, a system was implemented to allow the crew to escape in gliding flight , but this system would not have been usable to escape an explosion during ascent. Immediately after the disaster, the NASA Launch Recovery Director launched the two SRB recovery ships, MV Freedom Star and MV Liberty Star , to proceed to the impact area to recover debris, and requested the support of US military aircraft and ships. Owing to falling debris from

6216-406: The doors, shutting down telephone communications, and freezing computer terminals to collect data from them. The crew cabin, which was made of reinforced aluminum, separated in one piece from the rest of the orbiter. It then traveled in a ballistic arc , reaching the apogee of 65,000 feet (20 km) approximately 25 seconds after the explosion. At the time of separation, the maximum acceleration

6327-576: The evidence presented on the failure of the O-rings was inconclusive and that there was a substantial margin in the event of a failure or erosion. They stated that their decision was to proceed with the launch. Morton Thiokol leadership submitted a recommendation for launch, and the teleconference ended. Lawrence Mulloy, the NASA SRB project manager, called Arnold Aldrich, the NASA Mission Management Team Leader, to discuss

6438-532: The explosion, the RSO kept recovery forces from the impact area until 12:37   p.m. The size of the recovery operations increased to 12 aircraft and 8 ships by 7:00   p.m. Surface operations recovered debris from the orbiter and external tank. The surface recovery operations ended on February   7. On January   31, the US Navy was tasked with submarine recovery operations. The search efforts prioritized

6549-399: The field joint. The Space Shuttle main engines (SSMEs) were throttled down as scheduled for maximum dynamic pressure (max q) . During its ascent, the Space Shuttle encountered wind shear conditions beginning at T+37 , but they were within design limits of the vehicle and were countered by the guidance system. At T+58.788 , a tracking film camera captured the beginnings of a plume near

6660-731: The first tracking and data relay satellite , the Palapa B communications satellites, the Long Duration Exposure Facility , and the Earth Radiation Budget Satellite . It was also used as a test bed for the Manned Maneuvering Unit (MMU) and served as the platform to repair the malfunctioning SolarMax telescope . In addition, three consecutive Spacelab missions were conducted with the orbiter in 1985, one of which being

6771-407: The first time in April 1981, and was used to conduct in-orbit research, and deploy commercial, military, and scientific payloads. At launch, it consisted of the orbiter , which contained the crew and payload, the external tank (ET), and the two solid rocket boosters (SRBs). The orbiter was a reusable, winged vehicle that launched vertically and landed as a glider. Five orbiters were built during

SECTION 60

#1732772769442

6882-419: The following days; the number of reporters at KSC increased from 535 on the day of the launch to 1,467 reporters three days later. In the aftermath of the accident, NASA was criticized for not making key personnel available to the press. In the absence of information, the press published articles suggesting the external tank was the cause of the explosion. Until 2010, CNN's live broadcast of the launch and disaster

6993-438: The following year. The Space Shuttle mission, named STS-51-L , was the twenty-fifth Space Shuttle flight and the tenth flight of Challenger . The crew was announced on January   27,   1985, and was commanded by Dick Scobee . Michael Smith was assigned as the pilot, and the mission specialists were Ellison Onizuka , Judith Resnik , and Ronald McNair . The two payload specialists were Gregory Jarvis , who

7104-440: The funding for the Space Shuttle program, reviewed the findings of the Rogers Commission as part of its investigation. The committee agreed with the Rogers Commission that the failed SRB field joint was the cause of the accident, and that NASA and Morton Thiokol failed to act despite numerous warnings of the potential dangers of the SRB. The committee's report further emphasized safety considerations of other components and recommended

7215-555: The fuselage recovered from Space Shuttle Challenger can also be found at the "Forever Remembered" memorial at the Kennedy Space Center Visitor Complex in Florida. Debris from the orbiter sometimes washes up on the Florida coast. This is collected and transported to the silos for storage. Because of its early loss, Challenger was the only Space Shuttle that never wore the NASA "meatball" logo , and

7326-456: The initial explosion but was extensively damaged when it impacted the ocean. The remains of the crew were badly damaged from impact and submersion, and were not intact bodies. The USS Preserver made multiple trips to return debris and remains to port, and continued crew compartment recovery until April   4. During the recovery of the remains of the crew, Jarvis's body floated away and was not located until April   15, several weeks after

7437-428: The initial search for debris and covered 486 square nautical miles (1,670 km) at water depths between 70 feet (21 m) and 1,200 feet (370 m). The sonar operations discovered 881 potential locations for debris, of which 187 pieces were later confirmed to be from the orbiter. The debris from the SRBs was widely distributed due to the detonation of their linear shaped charges. The identification of SRB material

7548-450: The joint and burned through the aft attachment strut connecting it to the external propellant tank (ET), then into the tank itself. The collapse of the ET's internal structures and the rotation of the SRB that followed threw the shuttle stack, traveling at a speed of Mach 1.92, into a direction that allowed aerodynamic forces to tear the orbiter apart. Both SRBs detached from the now-destroyed ET and continued to fly uncontrollably until

7659-441: The joint had prevented the O-rings from creating a seal. Rainfall from the preceding time on the launchpad had likely accumulated within the field joint, further compromising the sealing capability of the O-rings. As a result, hot gas was able to travel past the O-rings and erode them. Molten aluminum oxides from the burned propellant resealed the joint and created a temporary barrier against further hot gas and flame escaping through

7770-555: The launch and explosion was provided by CNN . To promote the Teacher in Space program with McAuliffe as a crewmember, NASA had arranged for many students in the US to view the launch live at school with their teachers. Other networks, such as CBS , soon cut in to their affiliate feeds to broadcast continuous coverage of the disaster and its aftermath. Press interest in the disaster increased in

7881-462: The launch decision and weather concerns, but did not mention the O-ring discussion; the two agreed to proceed with the launch. An overnight measurement taken by the KSC Ice Team recorded the left SRB was 25 °F (−4 °C) and the right SRB was 8 °F (−13 °C). These measurements were recorded for engineering data and not reported, because the temperature of the SRBs was not part of

7992-717: The nation about the disaster from the Oval Office . On January   31, Ronald and Nancy Reagan traveled to the Johnson Space Center to speak at a memorial service honoring the crew members. During the ceremony, an Air Force band sang " God Bless America " as NASA T-38 Talon jets flew directly over the scene in the traditional missing-man formation . Soon after the disaster, US politicians expressed concern that White House officials, including Chief of Staff Donald Regan and Communications Director Pat Buchanan , had pressured NASA to launch Challenger before

8103-414: The ocean surface at 207 mph (333 km/h) approximately two minutes and 45 seconds after breakup. The estimated deceleration was 200 g , far exceeding structural limits of the crew compartment or crew survivability levels. The mid-deck floor had not suffered buckling or tearing, as would result from a rapid decompression, but stowed equipment showed damage consistent with decompression, and debris

8214-585: The orbiter are mostly buried in a missile silo located at Cape Canaveral LC-31 ; one piece is on display at the Kennedy Space Center Visitor Complex . Challenger was named after HMS Challenger , a British corvette that was the command ship for the Challenger Expedition , a pioneering global marine research expedition undertaken from 1872 through 1876. The Apollo 17 Lunar Module , which landed on

8325-461: The orbiter was pressed into operational service in the Space Shuttle program . Lessons learned from the first orbital flights of Columbia led to Challenger ' s design possessing fewer thermal protection system tiles and a lighter fuselage and wings. This led to it being 2,200 pounds (1,000 kilograms) lighter than Columbia , though still 5,700 pounds (2,600 kilograms) heavier than Discovery . During its three years of operation, Challenger

8436-614: The orbiter were found at Cocoa Beach . On November 10, 2022, NASA announced that a 20-foot (6 m) piece of the shuttle had been found near the site of a destroyed World War II-era aircraft off the coast of Florida. The discovery was aired on the History Channel on November 22, 2022. Almost all recovered non-organic debris from Challenger is buried in Cape Canaveral Space Force Station missile silos at LC-31 and LC-32 . On April 29, 1986,

8547-401: The orbiter, were concerned that ice would be violently thrown during launch and could potentially damage the orbiter's thermal protection system or be aspirated into one of the engines. Rocco Petrone , the head of Rockwell's space transportation division, and his team determined that the potential damage from ice made the mission unsafe to fly. Arnold Aldrich consulted with engineers at KSC and

8658-510: The orbiters Discovery and Atlantis joined the fleet, Challenger flew three missions a year from 1983 to 1985. Challenger , along with Atlantis , was modified at Kennedy Space Center to be able to carry the Centaur-G upper stage in its payload bay. If flight STS-51-L had been successful, Challenger ' s next mission would have been the deployment of the Ulysses probe with

8769-411: The other orbiters. Challenger was the first orbiter to have a heads-up display (HUD) system for use in the descent phase of a mission, and the first to feature Phase I main engines rated for 104% maximum thrust. After its first flight in April 1983, Challenger quickly became the workhorse of NASA 's Space Shuttle fleet, flying six of nine Space Shuttle missions in 1983 and 1984. Even when

8880-547: The other remains had been positively identified. Once remains were brought to port, pathologists from the Armed Forces Institute of Pathology worked to identify the human remains, but could not determine the exact cause of death for any of them. Medical examiners in Brevard County disputed the legality of transferring human remains to US military officials to conduct autopsies, and refused to issue

8991-420: The planning that went into mission development, along with potential concerns over crew safety and pressure to adhere to a schedule. Over a period of four months, the commission interviewed over 160 individuals, held at least 35 investigative sessions, and involved more than 6,000 NASA employees, contractors, and support personnel. The commission published its report on June 6, 1986. The commission determined that

9102-414: The potential danger with the SRB field joints. It noted that NASA accepted the risk of O-ring erosion without evaluating how it could potentially affect the safety of a mission. The commission concluded that the safety culture and management structure at NASA were insufficient to properly report, analyze, and prevent flight issues. It stated that the pressure to increase the rate of flights negatively affected

9213-402: The program's development, but he argued that multiple components, including the avionics and SSMEs in addition to the SRBs, were more dangerous and accident-prone than original NASA estimates had indicated. The US House Committee on Science and Technology conducted an investigation of the Challenger disaster and released a report on October   29, 1986. The committee, which had authorized

9324-508: The recovery of the right SRB, followed by the crew compartment, and then the remaining payload, orbiter pieces, and ET. The search for debris formally began on February   8 with the rescue and salvage ship USS  Preserver , and eventually grew to sixteen ships, of which three were managed by NASA, four by the US Navy , one by the US Air Force and eight by independent contractors. The surface ships used side-scan sonar to make

9435-525: The rescheduled State of the Union address on February 4, Reagan mentioned the deceased Challenger crew members and modified his remarks about the X-ray experiment as "launched and lost". In April   1986, the White House released a report that concluded there had been no pressure from the White House for NASA to launch Challenger prior to the State of the Union. Nationally televised live coverage of

9546-462: The right SRB. A leak had begun in the liquid hydrogen (LH2) tank of the ET at T+64.660 , as indicated by the changing shape of the plume. The SSMEs pivoted to compensate for the booster burn-through, which was creating an unexpected thrust on the vehicle. The pressure in the external LH2 tank began to drop at T+66.764 indicating that the flame had burned from the SRB into the tank. The crew and flight controllers made no indication they were aware of

9657-401: The safety of the launch. Morton Thiokol engineers expressed their concerns about the effect of low temperatures on the resilience of the rubber O-rings. As the colder temperatures lowered the elasticity of the rubber O-rings, the engineers feared that the O-rings would not be extruded to form a seal at the time of launch. The engineers argued that they did not have enough data to determine whether

9768-415: The scheduled January 28 State of the Union address, because Reagan had planned to mention the launch in his remarks. In March 1986, the White House released a copy of the original State of the Union speech. In that speech, Reagan had intended to mention an X-ray experiment launched on Challenger and designed by a guest he had invited to the address, but he did not further discuss the Challenger launch. In

9879-600: The scheduled launch time of 9:38   a.m. Based upon O-ring erosion that had occurred in warmer launches, Morton Thiokol engineers were concerned over the effect the record-cold temperatures would have on the seal provided by the SRB O-rings for the launch. Cecil Houston, the manager of the KSC office of the Marshall Space Flight Center, set up a conference call on the evening of January 27 to discuss

9990-412: The secondary O-ring could not provide a backup to the primary O-ring, as it would not necessarily form a seal in the event of joint rotation. The O-rings were redesignated as Criticality   1, removing the "R" to indicate it was no longer considered a redundant system. The first occurrence of in-flight O-ring erosion occurred on the right SRB on STS-2 in November   1981. In August   1984,

10101-402: The simulated internal pressure of a launch. Joint rotation, which occurred when the tang and clevis bent away from each other, reduced the pressure on the O-rings, which weakened their seals and made it possible for combustion gases to erode the O-rings. NASA engineers suggested that the field joints should be redesigned to include shims around the O-rings, but they received no response. In 1980,

10212-508: The situation. Obviously a major malfunction. We have no downlink." Soon afterwards, he said, "We have a report from the Flight Dynamics Officer that the vehicle has exploded. The flight director confirms that. We are looking at checking with the recovery forces to see what can be done at this point." In Mission Control, flight director Jay Greene ordered that contingency procedures be put into effect, which included locking

10323-431: The soot between the O-rings resulted from non-uniform pressure at the time of ignition. The January   1985 launch of STS-51-C was the coldest Space Shuttle launch to date. The air temperature was 62 °F (17 °C) at the time of launch, and the calculated O-ring temperature was 53 °F (12 °C). Post-flight analysis revealed erosion in primary O-rings in both SRBs. Morton Thiokol engineers determined that

10434-439: The switch could be moved. Later tests established that neither the force of the explosion nor the impact with the ocean could have moved them, indicating that Smith made the switch changes, presumably in a futile attempt to restore electrical power to the cockpit after the crew cabin detached from the rest of the orbiter. On July 28, 1986, NASA's Associate Administrator for Space Flight, former astronaut Richard H. Truly , released

10545-422: The tragedy firsthand. In March 1988 the federal government and Morton Thiokol Inc. agreed to pay $ 7.7 million in cash and annuities to the families of four of the seven Challenger astronauts as part of a settlement aimed at avoiding lawsuits in the nation's worst space disaster, according to government documents. The documents show that Morton Thiokol, which manufactured the faulty solid rocket boosters blamed for

10656-458: The two smaller, aft-mounted Orbital Maneuvering System (OMS) engines. When it launched, the orbiter was connected to the ET , which held the fuel for the SSMEs. The ET consisted of a larger tank for liquid hydrogen (LH2) and a smaller tank for liquid oxygen (LOX), both of which were required for the SSMEs to operate. After its fuel had been expended, the ET separated from the orbiter and reentered

10767-461: The vehicle and flight anomalies. At T+68 , the CAPCOM , Richard O. Covey , told the crew, " Challenger , go at throttle up," indicating that the SSMEs had throttled up to 104% thrust. In response to Covey, Scobee said, "Roger, go at throttle up"; this was the last communication from Challenger on the air-to-ground loop. At T+72.284 , the right SRB pulled away from the aft strut that attached it to

10878-731: Was a burst of static on the air-to-ground loop as the vehicle broke up, which was later attributed to ground-based radios searching for a signal from the destroyed spacecraft. NASA Public Affairs Officer Steve Nesbitt was initially unaware of the explosion and continued to read out flight information. At T+89 , after video of the explosion was seen in Mission Control , the Ground Control Officer reported "negative contact (and) loss of downlink " as they were no longer receiving transmissions from Challenger . Nesbitt stated, "Flight controllers here are looking very carefully at

10989-605: Was assigned to conduct research for the Hughes Aircraft Company , and Christa McAuliffe , who flew as part of the Teacher in Space Project . The primary mission of the Challenger crew was to use an Inertial Upper Stage (IUS) to deploy a Tracking and Data Relay Satellite (TDRS), named TDRS-B , that would have been part of a constellation to enable constant communication with orbiting spacecraft. The crew also planned to study Halley's Comet as it passed near

11100-863: Was buried at the National Memorial Cemetery of the Pacific in Honolulu , Hawaii. McNair was buried in Rest Lawn Memorial Park in Lake City, South Carolina, but his remains were later moved within the town to the Dr. Ronald E. McNair Memorial Park. Resnik was cremated and her ashes were scattered over the water. McAuliffe was buried at Calvary Cemetery in Concord, New Hampshire . Jarvis was cremated, and his ashes were scattered in

11211-479: Was considered a redundant system due to the secondary O-ring. Evaluations of the proposed SRB design in the early 1970s and field joint testing showed that the wide tolerances between the mated parts allowed the O-rings to be extruded from their seats rather than compressed. This extrusion was judged to be acceptable by NASA and Morton Thiokol despite concerns of NASA's engineers. A 1977 test showed that up to 0.052 inches (1.3 mm) of joint rotation occurred during

11322-408: Was destroyed in January 1986 soon after launch in a disaster that killed all seven crewmembers aboard. Initially manufactured as a test article not intended for spaceflight, it was used for ground testing of the Space Shuttle orbiter's structural design. However, after NASA found that their original plan to upgrade Enterprise for spaceflight would be more expensive than upgrading Challenger ,

11433-431: Was embedded between the two forward windows that may have caused a loss of pressure. Impact damage to the crew cabin was severe enough that it could not be determined whether the crew cabin had previously been damaged enough to lose pressurization. Unlike other spacecraft, the Space Shuttle did not allow for crew escape during powered flight. Launch escape systems had been considered during development, but NASA's conclusion

11544-450: Was flown on ten missions in the Space Shuttle program, spending over 62 days in space and completing almost 1,000 orbits around Earth. Following its maiden flight, Challenger supplanted Columbia as the leader of the Space Shuttle fleet, being the most-flown orbiter during all three years of its operation while Columbia itself was seldom used during the same time frame. Challenger was used for numerous civilian satellite launches, such as

11655-637: Was never modified with the MEDS "glass cockpit". The tail was never fitted with a drag chute, which was fitted to the remaining orbiters in 1992. Challenger and sister ship Columbia are the only two shuttles that never visited the Mir Space Station or the International Space Station. In September 2020 Netflix released Challenger: The Final Flight , a four-part miniseries created by Steven Leckart and Glen Zipper documenting

11766-453: Was primarily conducted by crewed submarines and submersibles. The vehicles were dispatched to investigate potential debris located during the search phase. Surface ships lifted the SRB debris with the help of technical divers and underwater remotely operated vehicles to attach the necessary slings to raise the debris with cranes. The solid propellant in the SRBs posed a risk, as it became more volatile after being submerged. Recovered portions of

11877-482: Was sent to a Lockheed test site in Palmdale, where it spent over 11 months in vibration tests designed to simulate entire shuttle flights, from launch to landing. To prevent damage during structural testing, qualification tests were performed to a safety factor of 1.2 times the design limit loads. The qualification tests were used to validate computational models, and compliance with the required 1.4 factor of safety

11988-450: Was shown by analysis. STA-099 was essentially a complete airframe of a Space Shuttle orbiter, with only a mockup crew module installed and thermal insulation placed on its forward fuselage. NASA planned to refit the prototype orbiter Enterprise (OV-101), used for flight testing, as the second operational orbiter; but Enterprise lacked most of the systems needed for flight, including a functional propulsion system, thermal insulation,

12099-453: Was that the Space Shuttle's expected high reliability would preclude the need for one. Modified SR-71 Blackbird ejection seats and full pressure suits were used for the two-person crews on the first four Space Shuttle orbital test flights, but they were disabled and later removed for the operational flights. Escape options for the operational flights were considered but not implemented due to their complexity, high cost, and heavy weight. After

12210-537: Was the 10th flight for the orbiter and the 25th flight of the Space Shuttle fleet. The crew was scheduled to deploy a communications satellite and study Halley's Comet while they were in orbit, in addition to taking schoolteacher Christa McAuliffe into space under the Teacher In Space program. The latter task resulted in a higher-than-usual media interest in and coverage of the mission; the launch and subsequent disaster were seen live in many schools across

12321-557: Was the only known on-location video footage from within range of the launch site. Additional amateur and professional recordings have since become publicly available. The Challenger accident has been used as a case study for subjects such as engineering safety , the ethics of whistleblowing , communications and group decision-making, and the dangers of groupthink . Roger Boisjoly and Allan McDonald became speakers who advocated for responsible workplace decision making and engineering ethics. Information designer Edward Tufte has argued that

#441558