On the morning of 28 January 1986, the Space Shuttle Challenger, mission 51-L, rose into the cold blue sky over the Cape. To exuberant spectators and breathless flight controllers, the launch appeared normal. Within 73 seconds after liftoff, however, the external tank ruptured, its liquid fuel exploded, and Challenger broke apart. Stunned spectators saw the explosion and the trails from the spiral flights of the solid rocket boosters, but the vapor cloud obscured how the orbiter shattered into large pieces. The crew cabin remained intact, trailing wires and plummeting to the Atlantic; the six astronauts and one school teacher aboard perished.
Over the next three months, a presidential commission led by former Secretary of State William P. Rogers and a NASA team investigated the accident. Television images of the flight revealed an anomalous flame from a joint between segments of the right-hand solid rocket motor. Photographs showed puffs of black smoke escaping from the joint during the first moments of ignition. Wreckage of the motor recovered from the Atlantic floor demonstrated the failure of the joint and proved that propulsion gases had melted surrounding metals and caused the explosion of the external tank.
Propulsion engineers from Morton- Thiokol Incorporated, the Utah company responsible for the solid rocket motors, testified that for years they had been discussing problems with the joints and their O-ring seals, especially in cold weather. The night before the launch they had warned Marshall officials that the anticipated cold weather could freeze the rubber O-rings and trigger disaster, but company executives and Marshall project managers had rejected calls for a launch delay.
The Rogers Commission concluded that managers at Marshall and Thiokol had known (or should have known) that the case joints were hazardous. They had failed to inform senior officials in the Shuttle program or to act promptly to reduce risks, and thus had failed to prevent a predictable accident. The commission decided that since Marshall officials had prior knowledge of the hazard, the accident primarily resulted from ineffective communications and management at the Center.
The commission's interpretation has dominated discourse about Challenger. Journalists and academics have relied on the commission's evidence, and have mainly added analysis to confirm its "bad communication" thesis. "Instant histories" often treated the scenarios in the Rogers Report as quasi-crimes, with journalist-authors reporting dirty deeds in the Shuttle program and telling scabrous stories about NASA officials with "the wrong stuff."
Unfortunately, the commission's interpretation oversimplified complex events. The oversimplifications emerged mainly because the commission and later pundits dismissed the testimony of Marshall engineers and managers and distorted information about hazards in written sources from the Shuttle program prior to the accident. Allowing Marshall engineers and managers to tell their story, based on pre-accident documents and on post-accident testimony and interviews, leads to a more realistic account of the events leading up to the accident than that found in the previous studies.
The story of the Marshall engineers and managers was that they had carefully studied the problems of the motor case joints and had concluded that the joints were not hazardous, that they had taken steps to improve the joints, and that they had communicated their conclusions and actions to superior Shuttle officials. Because they believed the joints were not hazardous, they did not predict the accident and could not have prevented it.
- STS-51L Challenger Mission Profile.
- Sequence of Major Events of the Challenger Accident.
- Image library of the STS-51L Challenger mission at Johnson Space Center.
- Movie clips of the STS-51L Challenger mission, from the Kennedy Space Center.
- Press Kit: this pre-launch document has been scanned in regular and high-resolution formats by volunteer Rich Orloff.
- Report of the Presidential Commission on the Space Shuttle Challenger Accident (commonly called the Rogers Commission Report), June 1986 and Implementations of the Recommendations, June 1987
- A description of modifications to the Solid Rocket Motors from the On-line Space Shuttle Reference Manual.
- Chapter IX - The Challenger Accident MSFC History
- A Challenger Bibliography: This is chapter 7 of the Space Shuttle bibliography published in 1992.
- The fate of Challenger's crew: Dr. Joseph P. Kerwin's investigation tried to determine the cause of the crew's deaths. His report and the accompanying press release are available.
- The transcript from the mission's voice recorder, which operated from T-2:05 until the accident.
- Biographical Information on the Challenger Crew.
- NASA Shuttle Web site on STS-51L.
- NASA Administrator's Statement, on the Tenth Anniversary of the Challenger Accident.
- President Reagan's Address to the Nation on January 28, 1986.
- Senator John Glenn's Remarks at a Memorial Service for Judith Resnick, February 3, 1986
- Post-Challenger Evaluation of Space Shuttle Risk Assessment and Management, a 1988 report from the National Academies of Science's Aeronautics and Space Engineering Board
- Feynman's Appendix to the Rogers Commission Report on the Space Shuttle Challenger Accident
- President Reagan's Eulogy: Remarks at a memorial service held in Houston following the Challenger disaster, January 31, 1986.
- Houston Chronicle's Remembrance of the Challenger Disaster, January 28, 1986
- An Analysis of the Challenger Accident by Mark Haisler and Robert Throop, from the University of Texas at Austin mechanical engineering department
- A case study in engineering ethics on the Challenger accident, from the departments of philosopy and mechanical engineering at Texas A&M University
- The Challenger Shuttle Disaster: A Failure in Decision Support System and Human Factors Management
- Roger Boisjoly on the Challenger Disaster
- Davinder Mahal's Challenger page
- Challenger Center for Space Science Education, a living memorial foundation, comprised of a network of educational learning centers around the world, dedicated to the educational spirit of STS 51-L.
- Selected Congressional Hearings and Reports from the Challenger Space Shuttle Accident, a series of links from the Government Printing Office to information related to the Challenger Accident
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