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EspañolSPACE SHUTTLE CHALLENGER DISASTER
(Redirected from Challenger Disaster)
The 'Space Shuttle ''Challenger'' disaster' occurred in the United States, over the Atlantic Ocean, off the coast of central Florida, at 11:39 a.m. EST (16:39 UTC) on January 28 1986. The Space Shuttle ''Challenger'' disintegrated 73 seconds into its flight after an O-ring seal in its right solid rocket booster (SRB) failed at liftoff. The seal failure caused a breach in the SRB joint it filled, allowing a flare to reach the outside and impinge upon the adjacent attachment hardware and external fuel tank. The SRB breach flare led to the separation of the right-hand SRB and the structural failure of the external tank. Aerodynamic forces promptly broke up the orbiter. The shuttle was destroyed and all seven crew members were killed. The crew compartment and many other vehicle fragments were eventually recovered from the ocean floor after a lengthy search and recovery operation.
The disaster resulted in a 32-month hiatus in the shuttle program and the formation of the Rogers Commission, a special commission appointed by United States President Ronald Reagan to investigate the accident. The Rogers Commission found that NASA's organizational culture and decision-making processes had been a key contributing factor to the accident. NASA managers had known that contractor Morton Thiokol's design of the SRBs contained a potentially catastrophic flaw in the O-rings since 1977, but they failed to address it properly. They also ignored warnings from engineers about the dangers of launching on such a cold day and had failed to adequately report these technical concerns to their superiors. The Rogers Commission offered NASA nine recommendations that were to be implemented before shuttle flights resumed.
Many schoolchildren viewed the launch live due to the presence on the crew of Christa McAuliffe, the first member of the Teacher in Space Project. Media coverage of the accident was extensive: one study reported that 85 percent of Americans surveyed had heard the news within an hour of the accident. The ''Challenger'' disaster has been used as a case study in many discussions of engineering safety and workplace ethics and inspired the 1990 television movie, ''Challenger''.
''Challenger'' was originally set to launch from Kennedy Space Center in Florida at 2:43 p.m. Eastern Standard Time (EST) on January 22. However, delays suffered by the previous mission, STS-61-C, caused the launch date to be pushed back to January 23 and then to January 24. Launch was then rescheduled to January 25 due to bad weather at the Transoceanic Abort Landing (TAL) site in Dakar, Senegal. NASA decided to use Casablanca as the TAL site, but because it was not equipped for night landings, the launch had to be moved to the morning (Florida time). Predictions of unacceptable weather at Kennedy Space Center (KSC) caused the launch to be rescheduled for 9:37 a.m. EST on January 27. According to Malcolm McConnell's book, ''Challenger: A Major Malfunction,'' NASA normally would have launched with the predicted forecast of a 50 percent chance of rain. However, managers wanted to invite Vice President George H.W. Bush to the launch, and did not want to risk having him sit and watch the window run out.
The launch was delayed the next day by problems with the exterior access hatch. First, one of the microswitch indicators used to verify that the hatch was safely locked malfunctioned.[1] Then, a stripped bolt prevented the closeout crew from removing a closing fixture from the orbiter's hatch.[2] When the fixture was finally sawn off, crosswinds at the Shuttle Landing Facility exceeded the limits for a Return to Launch Site (RTLS) abort.[3] The crew waited for the winds to die down until the launch window finally ran out, forcing yet another scrub.
Forecasts for January 28 predicted an unusually cold morning, with temperatures close to 31 °F (−0.5 °C), the minimum temperature permitted for launch. The low temperature had prompted concern from engineers at Morton Thiokol, the contractor responsible for the construction and maintenance of the shuttle's SRB. At a teleconference which took place on the evening of January 27, Thiokol engineers and managers discussed the weather conditions with NASA managers from Kennedy Space Center and Marshall Space Flight Center. Several engineers—most notably Roger Boisjoly, who had voiced similar concerns previously—expressed their concern about the effect of the temperature on the resilience of the rubber O-rings that sealed the joints of the SRBs. They argued that if the O-rings were colder than 53 °F (approximately 11.7 °C), there was no guarantee the O-rings would seal properly. This was an important consideration, since the O-rings had been designated as a "Criticality 1" component—meaning their failure would destroy ''Challenger'' and its crew. They also argued that the low overnight temperatures would almost certainly result in SRB temperatures below their redline of 40 °F. However, they were overruled by Morton Thiokol management, who recommended that the launch proceed as scheduled.[4]
Due to the low temperature, a significant amount of ice built up on the fixed service structure that stood beside the shuttle. The Kennedy Ice Team inadvertently pointed an infrared camera at the aft field joint of the right SRB and found the temperature to be only 8 °F (−13 °C). This was the result of supercooled air blowing on the joint from the liquid oxygen tank vent. It was much lower than the air temperature and far below the design specifications for the O-rings. This information was never communicated to the decision makers.[5]
Although the Ice Team had worked through the night removing ice—and not knowing of the super-cooled joint—engineers at Rockwell International, the shuttle's prime contractor, still expressed concern. They warned that during launch ice might be shaken loose and strike the shuttle, possibly due to the aspiration induced by the jet of exhaust from the SRBs. Although Rockwell viewed this situation as a launch constraint, Rockwell's managers at the Cape voiced their concerns in a manner that led Aldrich to go ahead with the launch. Aldrich decided to postpone the shuttle launch by an hour in order to give the ice team the time to perform another inspection. After that last inspection, during which the ice appeared to be melting, ''Challenger'' was finally cleared to launch at 11:38 a.m. EST.
The following account of the accident is derived from real time telemetry data and photographic analysis, as well as from transcripts of air-to-ground and mission control voice communications.[6] All times are given in seconds after launch and correspond to the telemetry time-codes from the closest instrumented event to each described event.[7]
At 6.6 seconds before liftoff, the three space shuttle main engines (SSME) ignited. Until liftoff actually occurs, the SSMEs can be safely shut down and the launch aborted if necessary. At liftoff time (T=0, which was at 11:38:00.010 EST), the three SSMEs were at 100% of their original rated performance, and began throttling up to 104% under computer control. At this moment, the two SRBs were ignited and hold-down bolts were released with explosives, freeing the vehicle from the pad. With the first vertical motion of the vehicle, the gaseous hydrogen vent arm retracted from the External Tank (ET) but failed to latch back. Review of film shot by pad cameras showed that the arm did not re-contact the vehicle, and thus it was ruled out as a contributing factor in the accident. The post-launch inspection of the pad also revealed that kick springs on four of the hold-down bolts were missing, but they were similarly ruled out as a possible cause.[8]
Later review of launch film showed that at T+0.678, strong puffs of dark grey smoke were emitted from the right-hand SRB near the aft strut that attaches the booster to the ET. The last smoke puff occurred at about T+2.733. The last view of smoke around the strut was at T+3.375. It was later determined that these smoke puffs were caused by the opening and closing of the aft field joint of the right-hand SRB. The booster's casing had ballooned under the stress of ignition. As a result of this ballooning, the metal parts of the casing bent away from each other, opening a gap through which hot gases above 5,000 °F (2,760 °C) leaked out. The primary O-ring was designed to close that gap, but was too cold to seal in time. The secondary O-ring was not in its seated position due to the metal bending. There was now no barrier to the gases, and both O-rings were vaporized across 70 degrees of arc. However, aluminum oxides from the burned solid propellant sealed the damaged joint, temporarily replacing the O-ring seal before actual flame rushed through the joint.
As the vehicle cleared the tower, the SSMEs were operating at 104% of their rated maximum thrust, and control switched from the Launch Control Center (LCC) at Kennedy to the Mission Control Center (MCC) in Houston, Texas. To prevent aerodynamic forces from tearing the shuttle apart, at T+28 the SSMEs began throttling down to limit the velocity of the shuttle in the dense lower atmosphere. At T+35.379, the SSMEs throttled back further to the planned 65%. Five seconds later, at about 19,000 feet (5800 m), ''Challenger'' passed through Mach 1. At T+51.860, the SSMEs began throttling back up to 104% as the vehicle approached Max Q, the period of maximum aerodynamic pressure on the vehicle.
Just as the shuttle approached Max Q, it slammed through the most intense wind shear ever experienced to date in the space shuttle program.
At T+58.788, a tracking film camera captured the beginnings of a plume near the aft attach strut on the right SRB. Unknown to those on ''Challenger'' or in Houston, ignited gas had begun to leak through a growing hole in one of the right-hand SRB's joints. The force of the wind shear shattered the temporary oxide seal that had taken the place of the damaged O-rings, removing the last barrier to flame rushing through the joint. Had it not been for the wind shear, the oxide seal would have almost certainly held all the way through booster burnout.
Within a second, the plume became well defined and intense. Internal pressure in the right SRB began to drop because of the rapidly enlarging hole in the failed joint, and at T+60.238 there was visual evidence of flame coming through the joint and impinging on the external tank.
At T+64.660, the plume suddenly changed shape, indicating that a leak had begun in the liquid hydrogen tank, located in the aft portion of the external tank. The nozzles of the main engines pivoted under computer control to compensate for the unbalanced thrust produced by the booster burn-through. The pressure in the shuttle's external liquid hydrogen tank began to drop at T+66.764, indicating the effect of the leak.
At this stage the situation still seemed normal both to the astronauts and to flight controllers. At T+68, the CAPCOM informed the crew that they were "go at throttle up", and Commander Dick Scobee confirmed the call. His response, "Roger, go at throttle up," was the last communication from ''Challenger'' on the air-to-ground loop.
At T+72.284, the right SRB apparently pulled away from the aft strut attaching it to the external tank. Later analysis of telemetry data showed a sudden lateral acceleration to the right at T+72.525, which may have been felt by the crew. The last statement captured by the crew cabin recorder came just half a second after this acceleration, when Pilot Michael J. Smith said "Uh oh". Smith may also have been responding to onboard indications of main engine performance, or to falling pressures in the external fuel tank.
At T+73.124, the aft dome of the liquid hydrogen tank failed, producing a propulsive force that pushed the hydrogen tank into the liquid oxygen tank in the forward part of the ET. At the same time, the right SRB rotated about the forward attach strut, and struck the intertank structure.
The breakup of the vehicle began at T+73.162 seconds and at an altitude of 48,000 feet (14.6 km).[9] With the external tank disintegrating, ''Challenger'' veered from its correct attitude with respect to the local air flow and was immediately torn apart by abnormal aerodynamic forces resulting in a load factor of up to 20''g'' — well over its design limit. The two SRBs, which can withstand greater aerodynamic loads, separated from the ET and continued in uncontrolled powered flight for another 37 seconds. The SRB casings were made of half an inch (12.7 mm) thick steel and were much stronger than the orbiter and ET; thus, both SRBs survived the breakup of the space shuttle stack, even though the right SRB was still suffering the effects of the joint burn-through that had set the destruction of ''Challenger'' in motion.[8]
In Mission Control, there was silence for a few seconds after the accident. Television screens showed a cloud of smoke and vapor where ''Challenger'' had been, with pieces of debris falling toward the ocean. At about T+89, flight director Jay Greene prompted his flight dynamics officer for information. The response was that "filters radar got discreting sources," a further indication that ''Challenger'' had broken into multiple pieces. The ground controller reported "negative contact, loss of downlink" of radio and telemetry data from ''Challenger''. Greene ordered his team to "watch your data carefully" and look for any sign that the Orbiter had escaped.
At T+110.250, the Range Safety Officer (RSO) at the Cape Canaveral Air Force Station sent radio signals that activated the range safety system's "destruct" packages on board both solid rocket boosters. This was a normal contingency procedure, undertaken because the RSO judged the free-flying SRBs a possible threat to land or sea. The same destruct signal would have destroyed the External Tank had it not already disintegrated.[11]
"Flight controllers here looking very carefully at the situation," reported public affairs officer Steve Nesbitt. "Obviously a major malfunction. We have no downlink." After a pause, Nesbitt said, "We have a report from the Flight Dynamics Officer that the vehicle has exploded."
Greene ordered that contingency procedures be put into effect at Mission Control; these procedures included locking the doors of the control center, shutting down telephone communications with the outside world, and following checklists that ensured that the relevant data was correctly recorded and preserved.
Contrary to the flight dynamics officer's initial statement, the shuttle and external tank did not actually "explode". Instead they rapidly disintegrated under tremendous aerodynamic forces, since the shuttle was past "Max Q", or maximum aerodynamic pressure. When the external tank disintegrated, the fuel and oxidizer stored within it were released, producing the appearance of a massive fireball. However, according to the NASA team that analyzed imagery after the accident, there was only "localized combustion" of propellant. Instead, the visible cloud was primarily composed of vapor and gases resulting from the release of the shuttle's liquid oxygen and liquid hydrogen propellant. Stored in cryogenic conditions, the liquid hydrogen could not have ignited rapidly enough to trigger an "explosion" in the traditional sense. Had there been a true explosion, the entire shuttle would have been instantly destroyed, killing the crew at that moment. The more robustly constructed crew cabin and SRBs survived the breakup of the launch vehicle; while the SRBs were subsequently detonated remotely, the detached cabin continued along a ballistic trajectory, and was observed exiting the cloud of gases at T+75.237. Twenty-five seconds after the breakup of the vehicle, the trajectory of the crew compartment peaked at a height of 65,000 feet (19.8 km); the breakup had occurred at only 48,000 feet (14.6 km).
During vehicle breakup, the robustly-constructed crew cabin detached in one piece and slowly tumbled. NASA estimated separation forces at about 12 to 20 times the force of gravity ''g'' very briefly; however, within two seconds, the forces on the cabin had already dropped to below 4 ''g'', and within ten seconds the cabin was undergoing free fall. These forces were likely insufficient to cause major injury. At least some of the astronauts were likely alive and briefly conscious after the breakup, because three of the four Personal Egress Air Packs (PEAPs) on the flight deck were found to have been activated. Investigators found their remaining unused air supply roughly consistent with the expected consumption during the 2 minute 45 second post-breakup trajectory. Whether the astronauts remained conscious long after the breakup is unknown, and largely depends on whether the detached crew cabin maintained pressure integrity. If it did not, time of useful consciousness at that altitude is just a few seconds; the PEAPs supplied only unpressurized air, and hence would not have helped the crew to retain consciousness. The crew cabin hit the ocean surface at roughly
334 km/h (207 mph), causing an instantaneous deceleration of over 200 ''g'', far beyond the structural limits of the crew compartment or crew survivability levels.
On July 28 1986, Rear Admiral Richard H. Truly, NASA's Associate Administrator for Space Flight and a former astronaut, released a report from Joseph P. Kerwin, biomedical specialist from the Johnson Space Center in Houston, relating to the deaths of the astronauts in the accident. Dr. Kerwin, a veteran of the Skylab 2 mission, had been commissioned to undertake the study soon after the accident. According to the Kerwin Report:
.
During powered flight of the space shuttle, crew escape was not possible. While launch escape systems were considered several times during shuttle development, NASA's conclusion was that the shuttle's expected high reliability would preclude the need for one. Modified SR-71 Blackbird ejection seats and full pressure suits were used on the first four shuttle orbital missions, which were considered test flights, but they were removed for the operational missions that followed. Providing a launch escape system for larger crews was considered undesirable due to "limited utility, technical complexity and excessive cost in dollars, weight or schedule delays."[12]
After the loss of ''Challenger'', the question was re-opened, and NASA considered several different options, including ejector seats, tractor rockets and bailing out through the bottom of the orbiter. However, NASA once again concluded that all of the launch escape systems considered would be impractical due to the sweeping vehicle modifications that would have been necessary and the resultant limitations on crew size. A bail-out system was designed to give the crew the option to leave the shuttle during gliding flight; however, this system would not have been available in the ''Challenger'' scenario.[13]
In the aftermath of the accident, NASA was criticized for its lack of openness with the press. ''The New York Times'' noted on the day after the accident that "neither Jay Greene, flight director for the ascent, nor any other person in the control room, was made available to the press by the space agency".[14] In the absence of reliable sources, the press turned to speculation; both ''The New York Times'' and United Press International ran stories suggesting that a fault with the external tank had caused the accident, despite the fact that NASA's internal investigation had quickly focused in on the solid rocket boosters.[15][16] "The space agency," wrote space reporter William Harwood, "stuck to its policy of strict secrecy about the details of the investigation, an uncharacteristic stance for an agency that long prided itself on openness."
On the night of the disaster, President Ronald Reagan had been scheduled to give his annual State of the Union Address. He initially announced that the address would go on as scheduled, but under mounting pressure he postponed the State of the Union Address for a week and gave a national address on the Challenger disaster from the Oval Office of the White House. It was written by Peggy Noonan, and finished with the following statement, which quoted from the poem "High Flight" by John Gillespie Magee, Jr.:
Three days later, Reagan and his wife Nancy traveled to the Johnson Space Center to be present at a memorial service honoring the astronauts. It was attended by six thousand NASA employees, as well as by the families of the crew.[17]
The families of the Challenger crew organized the Challenger Center for Space Science Education as a permanent memorial to the crew. Fifty learning centers have been established by this non-profit organization.
The City of Palmdale, the birthplace of the entire shuttle fleet, and its neighbor City of Lancaster, California, both renamed ''10th Street East'', from Avenue M to Edwards Air Force Base, to ''Challenger Way'' in honor of the lost shuttle and its crew. This was the road that the Challenger, Enterprise, and Columbia all were towed along in their initial move from Palmdale Airport to Edwards AFB after completion since Palmdale airport had not yet installed the shuttle crane for placement on the 747.
In addition, the City of Lancaster has built Challenger Middle School, and Challenger Memorial Hall at the former site of the Antelope Valley Fairgrounds, all in tribute to the Challenger shuttle and crew.
The remains of the crew that were identifiable were returned to their families on April 29 1986. Two of the crew members, Dick Scobee and Michael J. Smith, were buried by their families at Arlington National Cemetery at individual grave sites. Other crew remains were buried at the Space Shuttle ''Challenger'' Memorial in Arlington on May 20 1986.[18]
In the first minutes after the accident, recovery efforts were begun by NASA's Launch Recovery Director, who ordered the ships used by NASA for recovery of the solid rocket boosters to be sent to the location of the water impact. Search and rescue aircraft were also dispatched. At this stage, however, debris was still falling, and the Range Safety Officer (RSO) held both aircraft and ships out of the impact area until it was safe for them to enter. It was about an hour until the RSO allowed the recovery forces to begin their work.[19]
The search and rescue operations which took place in the first week after the ''Challenger'' accident were managed by the Department of Defense on behalf of NASA, with assistance from the United States Coast Guard, and mostly involved surface searches. According to the Coast Guard, "the operation was the largest surface search in which they had participated." This phase of operations lasted until February 7. Thereafter, recovery efforts were managed by a Search, Recovery, and Reconstruction team; its aim was to salvage debris that would help in determining the cause of the accident. Sonar, divers, remotely-operated submersibles and manned submersibles were all used during the search, which covered an area of 480 square nautical miles (1600 km²), and took place at depths of up to 1200 feet (370 m). By May 1, enough of the right solid rocket booster had been recovered to determine the original cause of the accident, and the major salvage operations were concluded. While some shallow-water recovery efforts continued, this was unconnected with the accident investigation; it aimed to recover debris for use in NASA's studies of the properties of materials used in spacecraft and launch vehicles. The recovery operation was able to pull 15 tons of debris from the ocean; 55% of Challenger, 5% of the crew cabin and 65% of the satellite cargo is still missing.[20] Some of the missing debris still washes up on Florida shores, such as on December 17 1996, nearly eleven years after the incident, when two large pieces of the shuttle were found at Cocoa Beach.[21] Under Title 18, United States Code, Section 641 it is against the law to be in possession of Challenger Debris and any newly discovered pieces have to be turned in to NASA.[22]
On board ''Challenger'' was an American flag, dubbed the Challenger flag, that was sponsored by Boy Scout Troop 514 of Monument, Colorado. It was recovered intact, still sealed in its cargo bag.
The 'Presidential Commission on the Space Shuttle ''Challenger'' Accident', also known as the Rogers Commission (after its chairman), was formed to investigate the disaster. The commission members were chairman and former Secretary of State William P. Rogers, astronauts Neil Armstrong (Vice Chairman) and Sally Ride, lawyer David C. Acheson, aviation specialists Eugene Covert and Robert Hotz, physicists Richard Feynman, Albert Wheelon, and Arthur B. C. Walker, Jr., former Air Force general Donald Kutyna, Robert Rummel, Joseph Sutter, and former pilot Chuck Yeager. The commission worked for several months and published a report of its findings.
It found that the ''Challenger'' accident was caused by a failure in the O-rings sealing the aft field joint on the right solid rocket booster, which allowed pressurized hot gases and eventually flame to "blow by" the O-ring and make contact with the adjacent external tank, causing structural failure. The failure of the O-rings was attributed to a design flaw, as their performance could be too easily compromised by factors including the low temperature on the day of launch.[23] More broadly, the report also considered the contributing causes of the accident. Most salient was the failure of both NASA and its contractor, Morton Thiokol, to respond adequately to the design flaw. This led the Rogers Commission to conclude that the ''Challenger'' disaster was "an accident rooted in history."[24]
The report also strongly criticized the decision making process that led to the launch of ''Challenger'', saying that it was seriously flawed. The report cited evidence that NASA managers did not know of Thiokol's initial concerns about the effects of the cold on the O-rings, and did not understand that Rockwell viewed the large amount of ice present on the pad as a constraint to launch.[25] It concluded that:
Main articles: Richard Feynman#Challenger disaster
One of the commission's best-known members was theoretical physicist Richard Feynman. His style of investigating with his own direct methods rather than following the commission schedule put him at odds with Rogers, who once commented, "Feynman is becoming a real pain." During a televised hearing, Feynman famously demonstrated how the O-rings became less resilient and subject to seal failures at ice-cold temperatures by immersing a sample of the material in a glass of ice water.[26]
Feynman was so critical of flaws in NASA's "safety culture" that he threatened to remove his name from the report unless it included his personal observations on the reliability of the shuttle, which appeared as Appendix F.[27][28] In the appendix, he argued that the estimates of reliability offered by NASA management were wildly unrealistic, differing as much as a thousandfold from the estimates of working engineers. "For a successful technology," he concluded, "reality must take precedence over public relations, for nature cannot be fooled."[29]
The U.S. House Committee on Science and Technology also conducted hearings, and on October 29 1986 released its own report on the ''Challenger'' accident.[30] The committee reviewed the findings of the Rogers Commission as part of its investigation, and agreed with the Rogers Commission as to the technical causes of the accident. However, it differed from the committee in its assessment of the accident's contributing causes.
After the ''Challenger'' accident, further shuttle flights were suspended, pending the results of the Rogers Commission investigation. Whereas NASA had held an internal inquiry into the Apollo 1 fire in 1967, its actions after ''Challenger'' were more constrained by the judgments of outside bodies. The Rogers Commission offered nine recommendations on improving safety in the space shuttle program, and NASA was directed by President Reagan to report back within thirty days as to how it planned to implement those recommendations.[31]
In response to the commission's recommendation, NASA initiated a total redesign of the space shuttle's solid rocket boosters, which was watched over by an independent oversight group as stipulated by the commission. NASA's contract with Morton Thiokol, the contractor responsible for the solid rocket boosters, included a clause stating that in the event of a failure leading to "loss of life or mission," Thiokol would forfeit $10 million of its incentive fee and formally accept legal liability for the failure. After the ''Challenger'' accident, Thiokol agreed to "voluntarily accept" the monetary penalty in exchange for not being forced to accept liability.[32]
NASA also created a new Office of Safety, Reliability and Quality Assurance, headed as the commission had specified by a NASA associate administrator who reported directly to the NASA administrator. George Martin, formerly of Martin Marietta, was appointed to this position.[33] Former ''Challenger'' flight director Jay Greene became chief of the Safety Division of the directorate.[34]
The unrealistically optimistic launch schedule pursued by NASA had been criticized by the Rogers Commission as a possible contributing cause to the accident. After the accident, NASA attempted to aim at a more realistic shuttle flight rate: it added another orbiter, ''Endeavour'', to the space shuttle fleet in order to replace ''Challenger'', and it worked with the Department of Defense in order to put more satellites in orbit using expendable launch vehicles rather than the shuttle.[35] In August 1986, President Reagan also announced that the shuttle would no longer carry commercial satellite payloads. After a 32-month hiatus, the next shuttle mission, STS-26, was launched on September 29 1988.
Although significant changes were made by NASA after the ''Challenger'' accident, many commentators have argued that the changes in its management structure and organizational culture were neither deep nor long-lasting. After the Space Shuttle ''Columbia'' disaster in 2003, attention once again focused on the attitude of NASA management towards safety issues. The Columbia Accident Investigation Board (CAIB) concluded that NASA had failed to learn many of the lessons of ''Challenger''. In particular, the agency had not set up a truly independent office for safety oversight; the CAIB felt that in this area, "NASA's response to the Rogers Commission did not meet the Commission's intent".[36] The CAIB believed that "the causes of the institutional failure responsible for ''Challenger'' have not been fixed," saying that the same "flawed decision making process" that had resulted in the ''Challenger'' accident was responsible for ''Columbia's destruction seventeen years later.[37]
While the presence of New Hampshire schoolteacher Christa McAuliffe on the ''Challenger'' crew had provoked some media interest, there was little live coverage of the launch. The only live national coverage was provided by CNN. After the accident, however, seventeen percent of respondents in one study reported that they had seen the shuttle launch, while eighty-five percent said that they had learned of the accident within an hour. As the authors of the paper reported, "only two studies have revealed more rapid dissemination [of news]." (One of those studies was of the spread of news in Dallas after President Kennedy's assassination, while the other was the spread of news among students at Kent State regarding President Franklin D. Roosevelt's death.)[38] Another study noted that "even those who were not watching television at the time of the disaster were almost certain to see the graphic pictures of the accident replayed as the television networks reported the story almost continuously for the rest of the day."[39] Children were even more likely than adults to have seen the accident live, since many children—forty-eight percent of nine to thirteen-year-olds, according to a ''New York Times'' poll—watched the launch at school.
Following the day of the accident, press interest remained high. While only 535 reporters were accredited to cover the launch, three days later there were 1467 reporters at Kennedy Space Center and another 1040 at Johnson Space Center. The accident made headlines in newspapers worldwide.
The ''Challenger'' accident has frequently been used as a case study in the study of subjects such as engineering safety, the ethics of whistleblowing, communications, and group decision-making. It is part of the required readings for engineers seeking a professional license in Canada[40] and other countries. Roger Boisjoly, the engineer who had warned about the effect of cold weather on the O-rings, left his job at Morton Thiokol and became a speaker on workplace ethics.[41] He argues that the caucus called by Morton Thiokol managers, which resulted in a recommendation to launch, "constituted the unethical decision-making forum resulting from intense customer intimidation."[42] Universities such as MIT, Texas A&M, the University of Texas, Drexel University, and the Gemstone program at the University of Maryland have also used the accident in classes on the ethics of engineering.[43][44]
Information designer Edward Tufte has used the ''Challenger'' accident as an example of the problems that can occur when information is presented unclearly. He argues that if Morton Thiokol engineers had more clearly presented the data that they had on the relationship between cold temperatures and burn-through in the solid rocket booster joints, they might have succeeded in persuading NASA managers to cancel the launch.[45] Tufte has also argued that poor presentation of information may have affected NASA decisions during the last flight of the ''Columbia''.[46]
In 1990, a television movie called ''Challenger'' was made about the events leading up to the launching of the shuttle. It was announced in May 2006 that another movie about the accident would be made, also called ''Challenger''. The movie was to be directed by Philip Kaufman – whose 1983 film ''The Right Stuff'' chronicled the early history of the space program – and would focus on the role of Richard Feynman in the ensuing investigation.[47]
The ''Challenger'' accident has also been referenced in numerous other television shows and movies. A March 1986 episode of the NBC television series ''Punky Brewster'', entitled "Accidents Happen," dealt with the title character's reaction to the disaster as she watched it on TV at school. In past episodes Punky had shown interest in becoming an astronaut, and now she was terrified that she might meet a similar fate; the episode dealt with her being afraid to pursue her career in aeronautics, and how she was convinced by her adopted parent Henry Warnimont, her teacher Mike Fulton, and former astronaut Buzz Aldrin to not give up on her dreams. The ''Farscape'' episode "Kansas" involved the main character traveling back in time in order to stop his astronaut father from becoming a crew member on the ''Challenger'' mission. The movie '' was dedicated to the memory of the Challenger crew, "whose courageous spirit shall live to the 23rd century and beyond."[48] Early in Oliver Stone's 1987 movie ''Wall Street'', John C. McGinley tells Charlie Sheen that Gordon Gekko (Michael Douglas) is so greedy he was short selling NASA stock within minutes of the shuttle's explosion (despite the fact that NASA, as a government agency, does not issue stock, and the scene is actually set in 1985, making it anachronistic).
French electronic music artist Jean Michel Jarre had composed a track on his album ''Rendez-Vous'' which he intended to be performed by ''Challenger'' astronaut Ronald McNair, a saxophonist and personal friend of Jarre. After McNair's death, Jarre dedicated the album to his memory, and performed a free concert in Houston in memory of the ''Challenger'' astronauts.[49] John Denver also wrote a tribute to the crew of ''Challenger'' on his album ''One World'', released in June 1986. The song was called ''Flying For Me'', and ended with a 73-second instrumental to commemorate the flight's duration.
Leslie Fish, a popular filk singer, recorded a dirge to the Challenger entitled "Nightmare Launch" which centers on the singer's plea that the disaster be a nightmare, rather than real. "You lived the dream that I had dreamt," the song says, "and I longed to be there too. Now send in someone please, and tell me it is not true..." "Fire in the sky," a song written by scientist Dr. Jordin Kare and performed by Kristoph Klover, chronicles man's rise into space and touches upon the Challenger disaster with the lines "But the gods do not give lightly of the powers they have made, and with Challenger and seven once again the price is paid. Though a nation watched her falling, yet a world could only cry, As they passed from us to glory, riding fire in the sky." Buzz Aldrin was moved to tears by the work. He subsequently endorsed it.
The Vandals, a California punk band, mentioned the Challenger in their song "How did this loser get this job." The song disparages the education system in general, exclaiming "We watch the shuttle launch, read J.D. Salinger/I know one teacher who I wish was on the Challenger."
The band Brave Saint Saturn, in the introduction to their song Two-Twenty-Nine, used the audio recording of the Challenger disaster just before the first verse.[50]
At least one comic book story depicted what might have happened if a superhero had saved Challenger. In the premiere issue of the 1995 limited series Astro City, the Superman-like character Samaritan made his first public appearance rescuing the orbiter in an effort to prevent a rather bleak future for the World from unfolding as a consequence of the disaster. While no story featuring Superman made any direct reference to Challenger, some stories that followed the event did show the character saving other Space Shuttle-like vehicles. These stories include the opening chapter of the 1986 graphic novel The Man of Steel (which, like Samaritan, was his first public appearance), the pilot episode for the 1993–97 TV series (in which the vehicle happened to be named "Messenger"), and the 2006 feature film Superman Returns.
In the 1996 play ''Hush'', by James Still, Maggie, the main character, talks about a dream she had in which she was flying through space and saw Christa McAuliffe teaching children to read on Venus. After her speech, Jana, a news reporter in the scene, turns to Frank, Maggie's father, and says (in reference to the ''Challenger'' disaster), "I was eating Chicken McNuggets when it blew up."
1. McConnell, Malcolm. ''Challenger: A Major Malfunction,'' pages 150–153.
2. McConnell, Malcolm. ''Challenger: A Major Malfunction,'' page 154.
3. Report of the Presidential Commission on the Space Shuttle ''Challenger'' Accident, Volume 1, chapter 2 Rogers Commission report
4. Report of the Presidential Commission on the Space Shuttle ''Challenger'' Accident, Volume 1, chapter 5 Rogers Commission report
5. Space Shuttle Challenger Disaster, Aerospaceweb.org
6. A major source for information about the ''Challenger'' accident is the STS 51-L Incident Integrated Events Timeline developed by the NASA Photo and TV Support Team as part of the Rogers Report (Appendix N). Numerous other timelines have been written based on this information. A detailed transcript of air-to-ground and mission control voice communications was put together by Rob Navias and William Harwood for CBS News, and integrates a timeline of events: Voyage Into History Chapter 13: The Timeline
7. NASA Photo and TV Support Team Report, Report of the Presidential Commission on the Space Shuttle ''Challenger'' Accident, Volume 3, Appendix N Rogers Commission report
8.
9. ''Challenger'' crew cause and time of death Kerwin, Joseph P.
10.
11. Rogers Commission report, Volume I, chapter 9, Range Safety Activities, January 28, 1986 Rogers Commission report
12. Report of the Presidential Commission on the Space Shuttle ''Challenger'' Accident, Volume 1, chapter 9, page 180 Rogers Commission report
13. Implementation of the Recommendations of the Presidential Commission on the Space Shuttle Challenger Accident, Recommendation VI Rogers Commission report
14. At Mission Control, Silence and Grief Fill a Day Long Dreaded Robert Reinhold
15. Voyage Into History; Chapter Six: The Reaction Archived by the Internet Archive on 2006-05-04.
16. See, for example, ''New Orleans Times-Picayune'', January 29 1986, p. 1.
17. Jensen, Claus, ''No Downlink'', p. 17.
18. The Shuttle Challenger Memorial, Arlington National Cemetery.
19. Report of the Presidential Commission on the Space Shuttle Challenger Accident, Volume 3, Appendix O: NASA Search, Recovery and Reconstruction Task Force Team Report Rogers Commission report
20. Famous Pictures Magazine - Challenger
21. CNN.com (1996), Shuttle ''Challenger'' debris washes up on shore. Retrieved on July 4 2006.
22. Seller admits to Challenger debris fraud
23. Report of the Presidential Commission on the Space Shuttle ''Challenger'' Accident, Volume 1, chapter 4, page 72 Rogers Commission report
24. Report of the Presidential Commission on the Space Shuttle ''Challenger'' Accident, Volume 1, chapter 6 Rogers Commission report
25. Report of the Presidential Commission on the Space Shuttle ''Challenger'' Accident, Volume 1, chapter 5 Rogers Commission report
26. Richard Feynman Dead at 69; Leading Theoretical Physicist Gleick, James
27. Report of the Presidential Commission on the Space Shuttle Challenger Accident This link includes App. F.
28. "What Do You Care What Other People Think?", , Ralph, Leighton, Bantam Books, , ISBN 0-553-34784-5
29. Feynman, Richard P. (1986) Appendix F - Personal Observations on Reliability of Shuttle
30. Investigation of the Challenger Accident; Report of the Committee on Science and Technology, House of Representatives.
31. Report to the President: Actions to Implement the Recommendations of the Presidential Commission on the Space Shuttle Challenger Accident
32. Jensen, Claus. ''No Downlink'', p. 355.
33. Implementation of the Recommendations of the Presidential Commission on the Space Shuttle Challenger Accident, Recommendation IV Rogers Commission report
34. J.H. Greene, NASA Johnson Space Center Oral History Project Biographical Data Sheet.
35. Implementation of the Recommendations of the Presidential Commission on the Space Shuttle Challenger Accident, Recommendation VII Rogers Commission report
36. Report of Columbia Accident Investigation Board, Volume I, chapter 7, page 178 (PDF) Columbia Accident Investigation Board
37. Report of Columbia Accident Investigation Board, Volume I, chapter 8, page 195 (PDF) Columbia Accident Investigation Board
38. Diffusion of News of Shuttle Disaster: What Role for Emotional Response?, , Daniel, Riffe, Journalism Quarterly,
39. How Children Reacted to Televised Coverage of the Space Shuttle Disaster, , John C., Wright, Journal of Communication,
40. Canadian Professional Engineering Practice and Ethics, , Gordon C., Andrews, Harcourt Canada, , ISBN 0-7747-3501-5
41. Roger Boisjoly and the ''Challenger'' disaster
42. Ethical Decisions - Morton Thiokol and the Space Shuttle ''Challenger'' Disaster: Telecon Meeting
43. Engineering Ethics:The Space Shuttle Challenger Disaster
44. Studies in Ethics, Safety, and Liability for Engineers: Space Shuttle Challenger
45. Edward Tufte. (1997) ''Visual Explanations'', ISBN 0-9613921-2-6, Chapter 2.
46. PowerPoint Does Rocket Science—and Better Techniques for Technical Reports Tufte, Edward
47. Media 8 To Produce "Challenger" Directed by Philip Kaufman
48. Star Trek IV: The Voyage Home-Production Notes, page 5
49. Rendez-Vous Houston
50. So Far From Home @ everything2
★ Ethical Decisions - Morton Thiokol and the Space Shuttle ''Challenger'' Disaster: Telecon Meeting
★ CNN.com (1996), Shuttle ''Challenger'' debris washes up on shore. Retrieved on July 4 2006.
★ Report of Columbia Accident Investigation Board Columbia Accident Investigation Board
★ Engineering Ethics:The Space Shuttle Challenger Disaster
★ Feynman, Richard P. (1986) Appendix F- Personal Observations on the reliability of the Shuttle.
★ Feynman, Richard P.. ''What Do You Care What Other People Think?'' ISBN 0-586-21855-6.
★ Greene, J.H., NASA Johnson Space Center Oral History Project Biographical Data Sheet.
★ Voyage Into History; Chapter Six: The Reaction Archived by the Internet Archive on 2006-05-04.
★ Studies in Ethics, Safety, and Liability for Engineers: Space Shuttle Challenger
★ Jensen, Claus. (1996) ''No Downlink: A Dramatic Narrative about the Challenger Accident and Our Time.'' New York: Farrar, Straus, Giroux. ISBN 0-374-12036-6.
★ ''Challenger'' crew cause and time of death Kerwin, Joseph P.
★ McConnell, Malcolm. (1987) ''Challenger: A Major Malfunction.'' Garden City, NY: Doubleday. ISBN 0-385-23877-0.
★ Media 8 To Produce "Challenger" Directed by Philip Kaufman
★ Report to the President: Actions to Implement the Recommendations of the Presidential Commission on the Space Shuttle Challenger Accident
★
★ At Mission Control, Silence and Grief Fill a Day Long Dreaded Robert Reinhold
★ Rendez-Vous Houston
★ Diffusion of News of Shuttle Disaster: What Role for Emotional Response?, , Daniel, Riffe, Journalism Quarterly,
★ Report of the Presidential Commission on the Space Shuttle ''Challenger'' Accident Rogers Commission report
★ Implementation of the Recommendations of the Presidential Commission on the Space Shuttle Challenger Accident Rogers Commission report
★ Ronald Reagan Presidential Library, Address to the nation on the ''Challenger'' disaster. Retrieved on July 4 2006.
★ Shuttle Challenger Memorial, Arlington National Cemetery. arlingtoncemetery.net. Retrieved on 2006-09-18.
★ Star Trek IV: The Voyage Home-Production Notes, page 5
★ Tufte, Edward. (1997) ''Visual Explanations'', ISBN 0-9613921-2-6.
★ Investigation of the Challenger Accident; Report of the Committee on Science and Technology, House of Representatives.
★ Vaughan, Diane. (1996) ''The Challenger Launch Decision: Risky Technology, Culture and Deviance at NASA''. Chicago: University of Chicago Press. ISBN 0-226-85176-1.
★ How Children Reacted to Televised Coverage of the Space Shuttle Disaster, , John C., Wright, Journal of Communication,
★ Challenger STS 51-L Accident NASA History Office
★ Sequence of Major Events of the Challenger Accident NASA Kennedy Space Center
★ Report of the Presidential Commission on the Space Shuttle ''Challenger'' Accident Rogers Commission
★ Challenger timeline
★ (Video)
★ CBS Radio news Bulletin of the Challenger Disaster Anchored by Christopher Glenn from 1/28/86 Part 1, Part 2, Part 3, Part 4.
The iconic image of Space Shuttle ''Challenger's smoke plume after its breakup 73 seconds after launch. The accident caused the deaths of all seven crew members of the STS-51-L mission.
The 'Space Shuttle ''Challenger'' disaster' occurred in the United States, over the Atlantic Ocean, off the coast of central Florida, at 11:39 a.m. EST (16:39 UTC) on January 28 1986. The Space Shuttle ''Challenger'' disintegrated 73 seconds into its flight after an O-ring seal in its right solid rocket booster (SRB) failed at liftoff. The seal failure caused a breach in the SRB joint it filled, allowing a flare to reach the outside and impinge upon the adjacent attachment hardware and external fuel tank. The SRB breach flare led to the separation of the right-hand SRB and the structural failure of the external tank. Aerodynamic forces promptly broke up the orbiter. The shuttle was destroyed and all seven crew members were killed. The crew compartment and many other vehicle fragments were eventually recovered from the ocean floor after a lengthy search and recovery operation.
The disaster resulted in a 32-month hiatus in the shuttle program and the formation of the Rogers Commission, a special commission appointed by United States President Ronald Reagan to investigate the accident. The Rogers Commission found that NASA's organizational culture and decision-making processes had been a key contributing factor to the accident. NASA managers had known that contractor Morton Thiokol's design of the SRBs contained a potentially catastrophic flaw in the O-rings since 1977, but they failed to address it properly. They also ignored warnings from engineers about the dangers of launching on such a cold day and had failed to adequately report these technical concerns to their superiors. The Rogers Commission offered NASA nine recommendations that were to be implemented before shuttle flights resumed.
Many schoolchildren viewed the launch live due to the presence on the crew of Christa McAuliffe, the first member of the Teacher in Space Project. Media coverage of the accident was extensive: one study reported that 85 percent of Americans surveyed had heard the news within an hour of the accident. The ''Challenger'' disaster has been used as a case study in many discussions of engineering safety and workplace ethics and inspired the 1990 television movie, ''Challenger''.
Pre-launch conditions and delays
Ice on the launch tower on the morning of the ''Challenger'' launch
''Challenger'' was originally set to launch from Kennedy Space Center in Florida at 2:43 p.m. Eastern Standard Time (EST) on January 22. However, delays suffered by the previous mission, STS-61-C, caused the launch date to be pushed back to January 23 and then to January 24. Launch was then rescheduled to January 25 due to bad weather at the Transoceanic Abort Landing (TAL) site in Dakar, Senegal. NASA decided to use Casablanca as the TAL site, but because it was not equipped for night landings, the launch had to be moved to the morning (Florida time). Predictions of unacceptable weather at Kennedy Space Center (KSC) caused the launch to be rescheduled for 9:37 a.m. EST on January 27. According to Malcolm McConnell's book, ''Challenger: A Major Malfunction,'' NASA normally would have launched with the predicted forecast of a 50 percent chance of rain. However, managers wanted to invite Vice President George H.W. Bush to the launch, and did not want to risk having him sit and watch the window run out.
The launch was delayed the next day by problems with the exterior access hatch. First, one of the microswitch indicators used to verify that the hatch was safely locked malfunctioned.[1] Then, a stripped bolt prevented the closeout crew from removing a closing fixture from the orbiter's hatch.[2] When the fixture was finally sawn off, crosswinds at the Shuttle Landing Facility exceeded the limits for a Return to Launch Site (RTLS) abort.[3] The crew waited for the winds to die down until the launch window finally ran out, forcing yet another scrub.
Forecasts for January 28 predicted an unusually cold morning, with temperatures close to 31 °F (−0.5 °C), the minimum temperature permitted for launch. The low temperature had prompted concern from engineers at Morton Thiokol, the contractor responsible for the construction and maintenance of the shuttle's SRB. At a teleconference which took place on the evening of January 27, Thiokol engineers and managers discussed the weather conditions with NASA managers from Kennedy Space Center and Marshall Space Flight Center. Several engineers—most notably Roger Boisjoly, who had voiced similar concerns previously—expressed their concern about the effect of the temperature on the resilience of the rubber O-rings that sealed the joints of the SRBs. They argued that if the O-rings were colder than 53 °F (approximately 11.7 °C), there was no guarantee the O-rings would seal properly. This was an important consideration, since the O-rings had been designated as a "Criticality 1" component—meaning their failure would destroy ''Challenger'' and its crew. They also argued that the low overnight temperatures would almost certainly result in SRB temperatures below their redline of 40 °F. However, they were overruled by Morton Thiokol management, who recommended that the launch proceed as scheduled.[4]
Due to the low temperature, a significant amount of ice built up on the fixed service structure that stood beside the shuttle. The Kennedy Ice Team inadvertently pointed an infrared camera at the aft field joint of the right SRB and found the temperature to be only 8 °F (−13 °C). This was the result of supercooled air blowing on the joint from the liquid oxygen tank vent. It was much lower than the air temperature and far below the design specifications for the O-rings. This information was never communicated to the decision makers.[5]
Although the Ice Team had worked through the night removing ice—and not knowing of the super-cooled joint—engineers at Rockwell International, the shuttle's prime contractor, still expressed concern. They warned that during launch ice might be shaken loose and strike the shuttle, possibly due to the aspiration induced by the jet of exhaust from the SRBs. Although Rockwell viewed this situation as a launch constraint, Rockwell's managers at the Cape voiced their concerns in a manner that led Aldrich to go ahead with the launch. Aldrich decided to postpone the shuttle launch by an hour in order to give the ice team the time to perform another inspection. After that last inspection, during which the ice appeared to be melting, ''Challenger'' was finally cleared to launch at 11:38 a.m. EST.
January 28 launch and failure
Liftoff and initial ascent
The following account of the accident is derived from real time telemetry data and photographic analysis, as well as from transcripts of air-to-ground and mission control voice communications.[6] All times are given in seconds after launch and correspond to the telemetry time-codes from the closest instrumented event to each described event.[7]
At 6.6 seconds before liftoff, the three space shuttle main engines (SSME) ignited. Until liftoff actually occurs, the SSMEs can be safely shut down and the launch aborted if necessary. At liftoff time (T=0, which was at 11:38:00.010 EST), the three SSMEs were at 100% of their original rated performance, and began throttling up to 104% under computer control. At this moment, the two SRBs were ignited and hold-down bolts were released with explosives, freeing the vehicle from the pad. With the first vertical motion of the vehicle, the gaseous hydrogen vent arm retracted from the External Tank (ET) but failed to latch back. Review of film shot by pad cameras showed that the arm did not re-contact the vehicle, and thus it was ruled out as a contributing factor in the accident. The post-launch inspection of the pad also revealed that kick springs on four of the hold-down bolts were missing, but they were similarly ruled out as a possible cause.[8]
Later review of launch film showed that at T+0.678, strong puffs of dark grey smoke were emitted from the right-hand SRB near the aft strut that attaches the booster to the ET. The last smoke puff occurred at about T+2.733. The last view of smoke around the strut was at T+3.375. It was later determined that these smoke puffs were caused by the opening and closing of the aft field joint of the right-hand SRB. The booster's casing had ballooned under the stress of ignition. As a result of this ballooning, the metal parts of the casing bent away from each other, opening a gap through which hot gases above 5,000 °F (2,760 °C) leaked out. The primary O-ring was designed to close that gap, but was too cold to seal in time. The secondary O-ring was not in its seated position due to the metal bending. There was now no barrier to the gases, and both O-rings were vaporized across 70 degrees of arc. However, aluminum oxides from the burned solid propellant sealed the damaged joint, temporarily replacing the O-ring seal before actual flame rushed through the joint.
''Challenger'' lifts off.
As the vehicle cleared the tower, the SSMEs were operating at 104% of their rated maximum thrust, and control switched from the Launch Control Center (LCC) at Kennedy to the Mission Control Center (MCC) in Houston, Texas. To prevent aerodynamic forces from tearing the shuttle apart, at T+28 the SSMEs began throttling down to limit the velocity of the shuttle in the dense lower atmosphere. At T+35.379, the SSMEs throttled back further to the planned 65%. Five seconds later, at about 19,000 feet (5800 m), ''Challenger'' passed through Mach 1. At T+51.860, the SSMEs began throttling back up to 104% as the vehicle approached Max Q, the period of maximum aerodynamic pressure on the vehicle.
Plume
Just as the shuttle approached Max Q, it slammed through the most intense wind shear ever experienced to date in the space shuttle program.
At T+58.788, a tracking film camera captured the beginnings of a plume near the aft attach strut on the right SRB. Unknown to those on ''Challenger'' or in Houston, ignited gas had begun to leak through a growing hole in one of the right-hand SRB's joints. The force of the wind shear shattered the temporary oxide seal that had taken the place of the damaged O-rings, removing the last barrier to flame rushing through the joint. Had it not been for the wind shear, the oxide seal would have almost certainly held all the way through booster burnout.
Within a second, the plume became well defined and intense. Internal pressure in the right SRB began to drop because of the rapidly enlarging hole in the failed joint, and at T+60.238 there was visual evidence of flame coming through the joint and impinging on the external tank.
At T+64.660, the plume suddenly changed shape, indicating that a leak had begun in the liquid hydrogen tank, located in the aft portion of the external tank. The nozzles of the main engines pivoted under computer control to compensate for the unbalanced thrust produced by the booster burn-through. The pressure in the shuttle's external liquid hydrogen tank began to drop at T+66.764, indicating the effect of the leak.
At this stage the situation still seemed normal both to the astronauts and to flight controllers. At T+68, the CAPCOM informed the crew that they were "go at throttle up", and Commander Dick Scobee confirmed the call. His response, "Roger, go at throttle up," was the last communication from ''Challenger'' on the air-to-ground loop.
Vehicle breakup
View of the Space Shuttle ''Challenger'' disaster from Cocoa Beach
At T+72.284, the right SRB apparently pulled away from the aft strut attaching it to the external tank. Later analysis of telemetry data showed a sudden lateral acceleration to the right at T+72.525, which may have been felt by the crew. The last statement captured by the crew cabin recorder came just half a second after this acceleration, when Pilot Michael J. Smith said "Uh oh". Smith may also have been responding to onboard indications of main engine performance, or to falling pressures in the external fuel tank.
At T+73.124, the aft dome of the liquid hydrogen tank failed, producing a propulsive force that pushed the hydrogen tank into the liquid oxygen tank in the forward part of the ET. At the same time, the right SRB rotated about the forward attach strut, and struck the intertank structure.
The breakup of the vehicle began at T+73.162 seconds and at an altitude of 48,000 feet (14.6 km).[9] With the external tank disintegrating, ''Challenger'' veered from its correct attitude with respect to the local air flow and was immediately torn apart by abnormal aerodynamic forces resulting in a load factor of up to 20''g'' — well over its design limit. The two SRBs, which can withstand greater aerodynamic loads, separated from the ET and continued in uncontrolled powered flight for another 37 seconds. The SRB casings were made of half an inch (12.7 mm) thick steel and were much stronger than the orbiter and ET; thus, both SRBs survived the breakup of the space shuttle stack, even though the right SRB was still suffering the effects of the joint burn-through that had set the destruction of ''Challenger'' in motion.[8]
Post-breakup flight controller dialog
Jay Greene at his console after the breakup of ''Challenger''
In Mission Control, there was silence for a few seconds after the accident. Television screens showed a cloud of smoke and vapor where ''Challenger'' had been, with pieces of debris falling toward the ocean. At about T+89, flight director Jay Greene prompted his flight dynamics officer for information. The response was that "filters radar got discreting sources," a further indication that ''Challenger'' had broken into multiple pieces. The ground controller reported "negative contact, loss of downlink" of radio and telemetry data from ''Challenger''. Greene ordered his team to "watch your data carefully" and look for any sign that the Orbiter had escaped.
At T+110.250, the Range Safety Officer (RSO) at the Cape Canaveral Air Force Station sent radio signals that activated the range safety system's "destruct" packages on board both solid rocket boosters. This was a normal contingency procedure, undertaken because the RSO judged the free-flying SRBs a possible threat to land or sea. The same destruct signal would have destroyed the External Tank had it not already disintegrated.[11]
"Flight controllers here looking very carefully at the situation," reported public affairs officer Steve Nesbitt. "Obviously a major malfunction. We have no downlink." After a pause, Nesbitt said, "We have a report from the Flight Dynamics Officer that the vehicle has exploded."
Greene ordered that contingency procedures be put into effect at Mission Control; these procedures included locking the doors of the control center, shutting down telephone communications with the outside world, and following checklists that ensured that the relevant data was correctly recorded and preserved.
No "explosion"
''Challenger'' begins to disintegrate.
Contrary to the flight dynamics officer's initial statement, the shuttle and external tank did not actually "explode". Instead they rapidly disintegrated under tremendous aerodynamic forces, since the shuttle was past "Max Q", or maximum aerodynamic pressure. When the external tank disintegrated, the fuel and oxidizer stored within it were released, producing the appearance of a massive fireball. However, according to the NASA team that analyzed imagery after the accident, there was only "localized combustion" of propellant. Instead, the visible cloud was primarily composed of vapor and gases resulting from the release of the shuttle's liquid oxygen and liquid hydrogen propellant. Stored in cryogenic conditions, the liquid hydrogen could not have ignited rapidly enough to trigger an "explosion" in the traditional sense. Had there been a true explosion, the entire shuttle would have been instantly destroyed, killing the crew at that moment. The more robustly constructed crew cabin and SRBs survived the breakup of the launch vehicle; while the SRBs were subsequently detonated remotely, the detached cabin continued along a ballistic trajectory, and was observed exiting the cloud of gases at T+75.237. Twenty-five seconds after the breakup of the vehicle, the trajectory of the crew compartment peaked at a height of 65,000 feet (19.8 km); the breakup had occurred at only 48,000 feet (14.6 km).
Cause and time of death
During vehicle breakup, the robustly-constructed crew cabin detached in one piece and slowly tumbled. NASA estimated separation forces at about 12 to 20 times the force of gravity ''g'' very briefly; however, within two seconds, the forces on the cabin had already dropped to below 4 ''g'', and within ten seconds the cabin was undergoing free fall. These forces were likely insufficient to cause major injury. At least some of the astronauts were likely alive and briefly conscious after the breakup, because three of the four Personal Egress Air Packs (PEAPs) on the flight deck were found to have been activated. Investigators found their remaining unused air supply roughly consistent with the expected consumption during the 2 minute 45 second post-breakup trajectory. Whether the astronauts remained conscious long after the breakup is unknown, and largely depends on whether the detached crew cabin maintained pressure integrity. If it did not, time of useful consciousness at that altitude is just a few seconds; the PEAPs supplied only unpressurized air, and hence would not have helped the crew to retain consciousness. The crew cabin hit the ocean surface at roughly
334 km/h (207 mph), causing an instantaneous deceleration of over 200 ''g'', far beyond the structural limits of the crew compartment or crew survivability levels.
On July 28 1986, Rear Admiral Richard H. Truly, NASA's Associate Administrator for Space Flight and a former astronaut, released a report from Joseph P. Kerwin, biomedical specialist from the Johnson Space Center in Houston, relating to the deaths of the astronauts in the accident. Dr. Kerwin, a veteran of the Skylab 2 mission, had been commissioned to undertake the study soon after the accident. According to the Kerwin Report:
Crew escape was not possible
.
During powered flight of the space shuttle, crew escape was not possible. While launch escape systems were considered several times during shuttle development, NASA's conclusion was that the shuttle's expected high reliability would preclude the need for one. Modified SR-71 Blackbird ejection seats and full pressure suits were used on the first four shuttle orbital missions, which were considered test flights, but they were removed for the operational missions that followed. Providing a launch escape system for larger crews was considered undesirable due to "limited utility, technical complexity and excessive cost in dollars, weight or schedule delays."[12]
After the loss of ''Challenger'', the question was re-opened, and NASA considered several different options, including ejector seats, tractor rockets and bailing out through the bottom of the orbiter. However, NASA once again concluded that all of the launch escape systems considered would be impractical due to the sweeping vehicle modifications that would have been necessary and the resultant limitations on crew size. A bail-out system was designed to give the crew the option to leave the shuttle during gliding flight; however, this system would not have been available in the ''Challenger'' scenario.[13]
Aftermath
In the aftermath of the accident, NASA was criticized for its lack of openness with the press. ''The New York Times'' noted on the day after the accident that "neither Jay Greene, flight director for the ascent, nor any other person in the control room, was made available to the press by the space agency".[14] In the absence of reliable sources, the press turned to speculation; both ''The New York Times'' and United Press International ran stories suggesting that a fault with the external tank had caused the accident, despite the fact that NASA's internal investigation had quickly focused in on the solid rocket boosters.[15][16] "The space agency," wrote space reporter William Harwood, "stuck to its policy of strict secrecy about the details of the investigation, an uncharacteristic stance for an agency that long prided itself on openness."
Tributes
The Space Shuttle ''Challenger'' Memorial, where some remains were buried
On the night of the disaster, President Ronald Reagan had been scheduled to give his annual State of the Union Address. He initially announced that the address would go on as scheduled, but under mounting pressure he postponed the State of the Union Address for a week and gave a national address on the Challenger disaster from the Oval Office of the White House. It was written by Peggy Noonan, and finished with the following statement, which quoted from the poem "High Flight" by John Gillespie Magee, Jr.:
Three days later, Reagan and his wife Nancy traveled to the Johnson Space Center to be present at a memorial service honoring the astronauts. It was attended by six thousand NASA employees, as well as by the families of the crew.[17]
The remains of the ''Challenger'' crew are transferred to a C-141 bound for Dover Air Force Base, Delaware
The families of the Challenger crew organized the Challenger Center for Space Science Education as a permanent memorial to the crew. Fifty learning centers have been established by this non-profit organization.
The City of Palmdale, the birthplace of the entire shuttle fleet, and its neighbor City of Lancaster, California, both renamed ''10th Street East'', from Avenue M to Edwards Air Force Base, to ''Challenger Way'' in honor of the lost shuttle and its crew. This was the road that the Challenger, Enterprise, and Columbia all were towed along in their initial move from Palmdale Airport to Edwards AFB after completion since Palmdale airport had not yet installed the shuttle crane for placement on the 747.
In addition, the City of Lancaster has built Challenger Middle School, and Challenger Memorial Hall at the former site of the Antelope Valley Fairgrounds, all in tribute to the Challenger shuttle and crew.
Funeral ceremonies
The remains of the crew that were identifiable were returned to their families on April 29 1986. Two of the crew members, Dick Scobee and Michael J. Smith, were buried by their families at Arlington National Cemetery at individual grave sites. Other crew remains were buried at the Space Shuttle ''Challenger'' Memorial in Arlington on May 20 1986.[18]
Recovery of debris
In the first minutes after the accident, recovery efforts were begun by NASA's Launch Recovery Director, who ordered the ships used by NASA for recovery of the solid rocket boosters to be sent to the location of the water impact. Search and rescue aircraft were also dispatched. At this stage, however, debris was still falling, and the Range Safety Officer (RSO) held both aircraft and ships out of the impact area until it was safe for them to enter. It was about an hour until the RSO allowed the recovery forces to begin their work.[19]
The search and rescue operations which took place in the first week after the ''Challenger'' accident were managed by the Department of Defense on behalf of NASA, with assistance from the United States Coast Guard, and mostly involved surface searches. According to the Coast Guard, "the operation was the largest surface search in which they had participated." This phase of operations lasted until February 7. Thereafter, recovery efforts were managed by a Search, Recovery, and Reconstruction team; its aim was to salvage debris that would help in determining the cause of the accident. Sonar, divers, remotely-operated submersibles and manned submersibles were all used during the search, which covered an area of 480 square nautical miles (1600 km²), and took place at depths of up to 1200 feet (370 m). By May 1, enough of the right solid rocket booster had been recovered to determine the original cause of the accident, and the major salvage operations were concluded. While some shallow-water recovery efforts continued, this was unconnected with the accident investigation; it aimed to recover debris for use in NASA's studies of the properties of materials used in spacecraft and launch vehicles. The recovery operation was able to pull 15 tons of debris from the ocean; 55% of Challenger, 5% of the crew cabin and 65% of the satellite cargo is still missing.[20] Some of the missing debris still washes up on Florida shores, such as on December 17 1996, nearly eleven years after the incident, when two large pieces of the shuttle were found at Cocoa Beach.[21] Under Title 18, United States Code, Section 641 it is against the law to be in possession of Challenger Debris and any newly discovered pieces have to be turned in to NASA.[22]
On board ''Challenger'' was an American flag, dubbed the Challenger flag, that was sponsored by Boy Scout Troop 514 of Monument, Colorado. It was recovered intact, still sealed in its cargo bag.
Rogers Commission investigation
The 'Presidential Commission on the Space Shuttle ''Challenger'' Accident', also known as the Rogers Commission (after its chairman), was formed to investigate the disaster. The commission members were chairman and former Secretary of State William P. Rogers, astronauts Neil Armstrong (Vice Chairman) and Sally Ride, lawyer David C. Acheson, aviation specialists Eugene Covert and Robert Hotz, physicists Richard Feynman, Albert Wheelon, and Arthur B. C. Walker, Jr., former Air Force general Donald Kutyna, Robert Rummel, Joseph Sutter, and former pilot Chuck Yeager. The commission worked for several months and published a report of its findings.
Members of the Rogers Commission arrive at Kennedy Space Center.
It found that the ''Challenger'' accident was caused by a failure in the O-rings sealing the aft field joint on the right solid rocket booster, which allowed pressurized hot gases and eventually flame to "blow by" the O-ring and make contact with the adjacent external tank, causing structural failure. The failure of the O-rings was attributed to a design flaw, as their performance could be too easily compromised by factors including the low temperature on the day of launch.[23] More broadly, the report also considered the contributing causes of the accident. Most salient was the failure of both NASA and its contractor, Morton Thiokol, to respond adequately to the design flaw. This led the Rogers Commission to conclude that the ''Challenger'' disaster was "an accident rooted in history."[24]
The report also strongly criticized the decision making process that led to the launch of ''Challenger'', saying that it was seriously flawed. The report cited evidence that NASA managers did not know of Thiokol's initial concerns about the effects of the cold on the O-rings, and did not understand that Rockwell viewed the large amount of ice present on the pad as a constraint to launch.[25] It concluded that:
Role of Richard Feynman
Main articles: Richard Feynman#Challenger disaster
One of the commission's best-known members was theoretical physicist Richard Feynman. His style of investigating with his own direct methods rather than following the commission schedule put him at odds with Rogers, who once commented, "Feynman is becoming a real pain." During a televised hearing, Feynman famously demonstrated how the O-rings became less resilient and subject to seal failures at ice-cold temperatures by immersing a sample of the material in a glass of ice water.[26]
Feynman was so critical of flaws in NASA's "safety culture" that he threatened to remove his name from the report unless it included his personal observations on the reliability of the shuttle, which appeared as Appendix F.[27][28] In the appendix, he argued that the estimates of reliability offered by NASA management were wildly unrealistic, differing as much as a thousandfold from the estimates of working engineers. "For a successful technology," he concluded, "reality must take precedence over public relations, for nature cannot be fooled."[29]
U.S. House Committee hearings
The U.S. House Committee on Science and Technology also conducted hearings, and on October 29 1986 released its own report on the ''Challenger'' accident.[30] The committee reviewed the findings of the Rogers Commission as part of its investigation, and agreed with the Rogers Commission as to the technical causes of the accident. However, it differed from the committee in its assessment of the accident's contributing causes.
NASA response
After the ''Challenger'' accident, further shuttle flights were suspended, pending the results of the Rogers Commission investigation. Whereas NASA had held an internal inquiry into the Apollo 1 fire in 1967, its actions after ''Challenger'' were more constrained by the judgments of outside bodies. The Rogers Commission offered nine recommendations on improving safety in the space shuttle program, and NASA was directed by President Reagan to report back within thirty days as to how it planned to implement those recommendations.[31]
In response to the commission's recommendation, NASA initiated a total redesign of the space shuttle's solid rocket boosters, which was watched over by an independent oversight group as stipulated by the commission. NASA's contract with Morton Thiokol, the contractor responsible for the solid rocket boosters, included a clause stating that in the event of a failure leading to "loss of life or mission," Thiokol would forfeit $10 million of its incentive fee and formally accept legal liability for the failure. After the ''Challenger'' accident, Thiokol agreed to "voluntarily accept" the monetary penalty in exchange for not being forced to accept liability.[32]
NASA also created a new Office of Safety, Reliability and Quality Assurance, headed as the commission had specified by a NASA associate administrator who reported directly to the NASA administrator. George Martin, formerly of Martin Marietta, was appointed to this position.[33] Former ''Challenger'' flight director Jay Greene became chief of the Safety Division of the directorate.[34]
The unrealistically optimistic launch schedule pursued by NASA had been criticized by the Rogers Commission as a possible contributing cause to the accident. After the accident, NASA attempted to aim at a more realistic shuttle flight rate: it added another orbiter, ''Endeavour'', to the space shuttle fleet in order to replace ''Challenger'', and it worked with the Department of Defense in order to put more satellites in orbit using expendable launch vehicles rather than the shuttle.[35] In August 1986, President Reagan also announced that the shuttle would no longer carry commercial satellite payloads. After a 32-month hiatus, the next shuttle mission, STS-26, was launched on September 29 1988.
Although significant changes were made by NASA after the ''Challenger'' accident, many commentators have argued that the changes in its management structure and organizational culture were neither deep nor long-lasting. After the Space Shuttle ''Columbia'' disaster in 2003, attention once again focused on the attitude of NASA management towards safety issues. The Columbia Accident Investigation Board (CAIB) concluded that NASA had failed to learn many of the lessons of ''Challenger''. In particular, the agency had not set up a truly independent office for safety oversight; the CAIB felt that in this area, "NASA's response to the Rogers Commission did not meet the Commission's intent".[36] The CAIB believed that "the causes of the institutional failure responsible for ''Challenger'' have not been fixed," saying that the same "flawed decision making process" that had resulted in the ''Challenger'' accident was responsible for ''Columbia's destruction seventeen years later.[37]
Popular impact
Media coverage
While the presence of New Hampshire schoolteacher Christa McAuliffe on the ''Challenger'' crew had provoked some media interest, there was little live coverage of the launch. The only live national coverage was provided by CNN. After the accident, however, seventeen percent of respondents in one study reported that they had seen the shuttle launch, while eighty-five percent said that they had learned of the accident within an hour. As the authors of the paper reported, "only two studies have revealed more rapid dissemination [of news]." (One of those studies was of the spread of news in Dallas after President Kennedy's assassination, while the other was the spread of news among students at Kent State regarding President Franklin D. Roosevelt's death.)[38] Another study noted that "even those who were not watching television at the time of the disaster were almost certain to see the graphic pictures of the accident replayed as the television networks reported the story almost continuously for the rest of the day."[39] Children were even more likely than adults to have seen the accident live, since many children—forty-eight percent of nine to thirteen-year-olds, according to a ''New York Times'' poll—watched the launch at school.
Following the day of the accident, press interest remained high. While only 535 reporters were accredited to cover the launch, three days later there were 1467 reporters at Kennedy Space Center and another 1040 at Johnson Space Center. The accident made headlines in newspapers worldwide.
Use as case study
The ''Challenger'' accident has frequently been used as a case study in the study of subjects such as engineering safety, the ethics of whistleblowing, communications, and group decision-making. It is part of the required readings for engineers seeking a professional license in Canada[40] and other countries. Roger Boisjoly, the engineer who had warned about the effect of cold weather on the O-rings, left his job at Morton Thiokol and became a speaker on workplace ethics.[41] He argues that the caucus called by Morton Thiokol managers, which resulted in a recommendation to launch, "constituted the unethical decision-making forum resulting from intense customer intimidation."[42] Universities such as MIT, Texas A&M, the University of Texas, Drexel University, and the Gemstone program at the University of Maryland have also used the accident in classes on the ethics of engineering.[43][44]
Information designer Edward Tufte has used the ''Challenger'' accident as an example of the problems that can occur when information is presented unclearly. He argues that if Morton Thiokol engineers had more clearly presented the data that they had on the relationship between cold temperatures and burn-through in the solid rocket booster joints, they might have succeeded in persuading NASA managers to cancel the launch.[45] Tufte has also argued that poor presentation of information may have affected NASA decisions during the last flight of the ''Columbia''.[46]
References in popular culture
In 1990, a television movie called ''Challenger'' was made about the events leading up to the launching of the shuttle. It was announced in May 2006 that another movie about the accident would be made, also called ''Challenger''. The movie was to be directed by Philip Kaufman – whose 1983 film ''The Right Stuff'' chronicled the early history of the space program – and would focus on the role of Richard Feynman in the ensuing investigation.[47]
The ''Challenger'' accident has also been referenced in numerous other television shows and movies. A March 1986 episode of the NBC television series ''Punky Brewster'', entitled "Accidents Happen," dealt with the title character's reaction to the disaster as she watched it on TV at school. In past episodes Punky had shown interest in becoming an astronaut, and now she was terrified that she might meet a similar fate; the episode dealt with her being afraid to pursue her career in aeronautics, and how she was convinced by her adopted parent Henry Warnimont, her teacher Mike Fulton, and former astronaut Buzz Aldrin to not give up on her dreams. The ''Farscape'' episode "Kansas" involved the main character traveling back in time in order to stop his astronaut father from becoming a crew member on the ''Challenger'' mission. The movie '' was dedicated to the memory of the Challenger crew, "whose courageous spirit shall live to the 23rd century and beyond."[48] Early in Oliver Stone's 1987 movie ''Wall Street'', John C. McGinley tells Charlie Sheen that Gordon Gekko (Michael Douglas) is so greedy he was short selling NASA stock within minutes of the shuttle's explosion (despite the fact that NASA, as a government agency, does not issue stock, and the scene is actually set in 1985, making it anachronistic).
French electronic music artist Jean Michel Jarre had composed a track on his album ''Rendez-Vous'' which he intended to be performed by ''Challenger'' astronaut Ronald McNair, a saxophonist and personal friend of Jarre. After McNair's death, Jarre dedicated the album to his memory, and performed a free concert in Houston in memory of the ''Challenger'' astronauts.[49] John Denver also wrote a tribute to the crew of ''Challenger'' on his album ''One World'', released in June 1986. The song was called ''Flying For Me'', and ended with a 73-second instrumental to commemorate the flight's duration.
Leslie Fish, a popular filk singer, recorded a dirge to the Challenger entitled "Nightmare Launch" which centers on the singer's plea that the disaster be a nightmare, rather than real. "You lived the dream that I had dreamt," the song says, "and I longed to be there too. Now send in someone please, and tell me it is not true..." "Fire in the sky," a song written by scientist Dr. Jordin Kare and performed by Kristoph Klover, chronicles man's rise into space and touches upon the Challenger disaster with the lines "But the gods do not give lightly of the powers they have made, and with Challenger and seven once again the price is paid. Though a nation watched her falling, yet a world could only cry, As they passed from us to glory, riding fire in the sky." Buzz Aldrin was moved to tears by the work. He subsequently endorsed it.
The Vandals, a California punk band, mentioned the Challenger in their song "How did this loser get this job." The song disparages the education system in general, exclaiming "We watch the shuttle launch, read J.D. Salinger/I know one teacher who I wish was on the Challenger."
The band Brave Saint Saturn, in the introduction to their song Two-Twenty-Nine, used the audio recording of the Challenger disaster just before the first verse.[50]
At least one comic book story depicted what might have happened if a superhero had saved Challenger. In the premiere issue of the 1995 limited series Astro City, the Superman-like character Samaritan made his first public appearance rescuing the orbiter in an effort to prevent a rather bleak future for the World from unfolding as a consequence of the disaster. While no story featuring Superman made any direct reference to Challenger, some stories that followed the event did show the character saving other Space Shuttle-like vehicles. These stories include the opening chapter of the 1986 graphic novel The Man of Steel (which, like Samaritan, was his first public appearance), the pilot episode for the 1993–97 TV series (in which the vehicle happened to be named "Messenger"), and the 2006 feature film Superman Returns.
In the 1996 play ''Hush'', by James Still, Maggie, the main character, talks about a dream she had in which she was flying through space and saw Christa McAuliffe teaching children to read on Venus. After her speech, Jana, a news reporter in the scene, turns to Frank, Maggie's father, and says (in reference to the ''Challenger'' disaster), "I was eating Chicken McNuggets when it blew up."
Media
Notes
1. McConnell, Malcolm. ''Challenger: A Major Malfunction,'' pages 150–153.
2. McConnell, Malcolm. ''Challenger: A Major Malfunction,'' page 154.
3. Report of the Presidential Commission on the Space Shuttle ''Challenger'' Accident, Volume 1, chapter 2 Rogers Commission report
4. Report of the Presidential Commission on the Space Shuttle ''Challenger'' Accident, Volume 1, chapter 5 Rogers Commission report
5. Space Shuttle Challenger Disaster, Aerospaceweb.org
6. A major source for information about the ''Challenger'' accident is the STS 51-L Incident Integrated Events Timeline developed by the NASA Photo and TV Support Team as part of the Rogers Report (Appendix N). Numerous other timelines have been written based on this information. A detailed transcript of air-to-ground and mission control voice communications was put together by Rob Navias and William Harwood for CBS News, and integrates a timeline of events: Voyage Into History Chapter 13: The Timeline
7. NASA Photo and TV Support Team Report, Report of the Presidential Commission on the Space Shuttle ''Challenger'' Accident, Volume 3, Appendix N Rogers Commission report
8.
9. ''Challenger'' crew cause and time of death Kerwin, Joseph P.
10.
11. Rogers Commission report, Volume I, chapter 9, Range Safety Activities, January 28, 1986 Rogers Commission report
12. Report of the Presidential Commission on the Space Shuttle ''Challenger'' Accident, Volume 1, chapter 9, page 180 Rogers Commission report
13. Implementation of the Recommendations of the Presidential Commission on the Space Shuttle Challenger Accident, Recommendation VI Rogers Commission report
14. At Mission Control, Silence and Grief Fill a Day Long Dreaded Robert Reinhold
15. Voyage Into History; Chapter Six: The Reaction Archived by the Internet Archive on 2006-05-04.
16. See, for example, ''New Orleans Times-Picayune'', January 29 1986, p. 1.
17. Jensen, Claus, ''No Downlink'', p. 17.
18. The Shuttle Challenger Memorial, Arlington National Cemetery.
19. Report of the Presidential Commission on the Space Shuttle Challenger Accident, Volume 3, Appendix O: NASA Search, Recovery and Reconstruction Task Force Team Report Rogers Commission report
20. Famous Pictures Magazine - Challenger
21. CNN.com (1996), Shuttle ''Challenger'' debris washes up on shore. Retrieved on July 4 2006.
22. Seller admits to Challenger debris fraud
23. Report of the Presidential Commission on the Space Shuttle ''Challenger'' Accident, Volume 1, chapter 4, page 72 Rogers Commission report
24. Report of the Presidential Commission on the Space Shuttle ''Challenger'' Accident, Volume 1, chapter 6 Rogers Commission report
25. Report of the Presidential Commission on the Space Shuttle ''Challenger'' Accident, Volume 1, chapter 5 Rogers Commission report
26. Richard Feynman Dead at 69; Leading Theoretical Physicist Gleick, James
27. Report of the Presidential Commission on the Space Shuttle Challenger Accident This link includes App. F.
28. "What Do You Care What Other People Think?", , Ralph, Leighton, Bantam Books, , ISBN 0-553-34784-5
29. Feynman, Richard P. (1986) Appendix F - Personal Observations on Reliability of Shuttle
30. Investigation of the Challenger Accident; Report of the Committee on Science and Technology, House of Representatives.
31. Report to the President: Actions to Implement the Recommendations of the Presidential Commission on the Space Shuttle Challenger Accident
32. Jensen, Claus. ''No Downlink'', p. 355.
33. Implementation of the Recommendations of the Presidential Commission on the Space Shuttle Challenger Accident, Recommendation IV Rogers Commission report
34. J.H. Greene, NASA Johnson Space Center Oral History Project Biographical Data Sheet.
35. Implementation of the Recommendations of the Presidential Commission on the Space Shuttle Challenger Accident, Recommendation VII Rogers Commission report
36. Report of Columbia Accident Investigation Board, Volume I, chapter 7, page 178 (PDF) Columbia Accident Investigation Board
37. Report of Columbia Accident Investigation Board, Volume I, chapter 8, page 195 (PDF) Columbia Accident Investigation Board
38. Diffusion of News of Shuttle Disaster: What Role for Emotional Response?, , Daniel, Riffe, Journalism Quarterly,
39. How Children Reacted to Televised Coverage of the Space Shuttle Disaster, , John C., Wright, Journal of Communication,
40. Canadian Professional Engineering Practice and Ethics, , Gordon C., Andrews, Harcourt Canada, , ISBN 0-7747-3501-5
41. Roger Boisjoly and the ''Challenger'' disaster
42. Ethical Decisions - Morton Thiokol and the Space Shuttle ''Challenger'' Disaster: Telecon Meeting
43. Engineering Ethics:The Space Shuttle Challenger Disaster
44. Studies in Ethics, Safety, and Liability for Engineers: Space Shuttle Challenger
45. Edward Tufte. (1997) ''Visual Explanations'', ISBN 0-9613921-2-6, Chapter 2.
46. PowerPoint Does Rocket Science—and Better Techniques for Technical Reports Tufte, Edward
47. Media 8 To Produce "Challenger" Directed by Philip Kaufman
48. Star Trek IV: The Voyage Home-Production Notes, page 5
49. Rendez-Vous Houston
50. So Far From Home @ everything2
References
★ Ethical Decisions - Morton Thiokol and the Space Shuttle ''Challenger'' Disaster: Telecon Meeting
★ CNN.com (1996), Shuttle ''Challenger'' debris washes up on shore. Retrieved on July 4 2006.
★ Report of Columbia Accident Investigation Board Columbia Accident Investigation Board
★ Engineering Ethics:The Space Shuttle Challenger Disaster
★ Feynman, Richard P. (1986) Appendix F- Personal Observations on the reliability of the Shuttle.
★ Feynman, Richard P.. ''What Do You Care What Other People Think?'' ISBN 0-586-21855-6.
★ Greene, J.H., NASA Johnson Space Center Oral History Project Biographical Data Sheet.
★ Voyage Into History; Chapter Six: The Reaction Archived by the Internet Archive on 2006-05-04.
★ Studies in Ethics, Safety, and Liability for Engineers: Space Shuttle Challenger
★ Jensen, Claus. (1996) ''No Downlink: A Dramatic Narrative about the Challenger Accident and Our Time.'' New York: Farrar, Straus, Giroux. ISBN 0-374-12036-6.
★ ''Challenger'' crew cause and time of death Kerwin, Joseph P.
★ McConnell, Malcolm. (1987) ''Challenger: A Major Malfunction.'' Garden City, NY: Doubleday. ISBN 0-385-23877-0.
★ Media 8 To Produce "Challenger" Directed by Philip Kaufman
★ Report to the President: Actions to Implement the Recommendations of the Presidential Commission on the Space Shuttle Challenger Accident
★
★ At Mission Control, Silence and Grief Fill a Day Long Dreaded Robert Reinhold
★ Rendez-Vous Houston
★ Diffusion of News of Shuttle Disaster: What Role for Emotional Response?, , Daniel, Riffe, Journalism Quarterly,
★ Report of the Presidential Commission on the Space Shuttle ''Challenger'' Accident Rogers Commission report
★ Implementation of the Recommendations of the Presidential Commission on the Space Shuttle Challenger Accident Rogers Commission report
★ Ronald Reagan Presidential Library, Address to the nation on the ''Challenger'' disaster. Retrieved on July 4 2006.
★ Shuttle Challenger Memorial, Arlington National Cemetery. arlingtoncemetery.net. Retrieved on 2006-09-18.
★ Star Trek IV: The Voyage Home-Production Notes, page 5
★ Tufte, Edward. (1997) ''Visual Explanations'', ISBN 0-9613921-2-6.
★ Investigation of the Challenger Accident; Report of the Committee on Science and Technology, House of Representatives.
★ Vaughan, Diane. (1996) ''The Challenger Launch Decision: Risky Technology, Culture and Deviance at NASA''. Chicago: University of Chicago Press. ISBN 0-226-85176-1.
★ How Children Reacted to Televised Coverage of the Space Shuttle Disaster, , John C., Wright, Journal of Communication,
External links
★ Challenger STS 51-L Accident NASA History Office
★ Sequence of Major Events of the Challenger Accident NASA Kennedy Space Center
★ Report of the Presidential Commission on the Space Shuttle ''Challenger'' Accident Rogers Commission
★ Challenger timeline
★ (Video)
★ CBS Radio news Bulletin of the Challenger Disaster Anchored by Christopher Glenn from 1/28/86 Part 1, Part 2, Part 3, Part 4.
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