On January 28, 1986, the space shuttle Challenger lifted off from Cape Canaveral, Florida, carrying a crew of seven — among them Christa McAuliffe, a New Hampshire schoolteacher selected to be the first teacher in space. Seventy-three seconds into the flight, as families watched from the ground and classrooms watched live across the country, the shuttle broke apart. All seven crew members were killed.
The launch had gone ahead on the coldest morning in shuttle history, with temperatures around 36 degrees Fahrenheit, over the objections of engineers at the booster manufacturer who warned that the rubber O-rings sealing the joints of the solid rocket boosters might not seal properly in such cold.
The Presidential Commission chaired by former Secretary of State William P. Rogers identified the physical cause: hot gas escaped through the failed O-ring seal in the aft field joint of the right solid rocket booster, burning through the joint; the booster broke away and the external fuel tank collapsed, and the vehicle was torn apart by aerodynamic forces. The commission’s second finding was about NASA itself — a flawed decision-making process in which schedule pressure and a management structure that muted engineers’ concerns allowed a known and growing risk to be accepted, flight after flight. Physicist Richard Feynman’s appendix to the report became a landmark statement on engineering honesty and the reality of risk.
The shuttle fleet was grounded for nearly three years. The booster joints were redesigned with a third O-ring, capture features and joint heaters, NASA’s safety and launch-decision structure was overhauled, and managers responsible for the launch decision left the agency. American human spaceflight resumed with the launch of Discovery on September 29, 1988.
Download the Rogers Commission Report — Volume I (25.1 MB file)