The Challenger Disaster - 1986

Conditions at Kennedy Space Center in Florida were anything but ideal for a Space Shuttle launch on the morning of January 28, 1986. The temperature was 31 degrees farenheit, far colder than for any previous shuttle launch. Engineers at Morton Thiokold (manufacturer of the Shuttle's solid rocket boosters, or SRBs) warned against launching in such cold temperatures. They feared there was a distinct possibility that the O-rings on the SRBs might not seal correctly in such temperatures. Engineers at Rockwell International (primary contractor for the Shuttle program) also expressed grave concerns over the temperature. Primarily over the possibility that ice, which had accumulated all over the Shuttle and adjacent launch pad, would break free during launch and damage the critical heat absorbing tiles on the Shuttle's underbelly. Both sets of engineers advised against launching.

Their bosses however, feeling the pressure to launch after a week of delays and in the full glare of the public spotlight due to the presence of the first "teacher in space" (Christa McAuliffe) among the crew, overroad their engineers and gave STS-51L the green light.

They should have listened.

Just 73 seconds after lift off the Thiokold engineer's worst nightmares were realized as super-heated gas leaking through a failed O-ring on the right hand SRB burned through the external fuel tank causing a cascading series of events that led to the breakup of the Shuttle Challenger 48,000 feet over the Atlantic. Contrary to popular belief at the time the Shuttle was not torn apart by the explosion of gases in the external fuel tank but instead by aerodynamic forces exerted on the orbiter when it veered off its intended trajectory due to thrust anomolies coming from the right SRB (which had broken loose) and the external fuel tank. The last words heard from Pilot Michael Smith just milliseconds before the orbitor was torn apart were an ominous "Uh oh."

In a grissly discovery made some weeks later it was learned that several members of the crew had apparently survived the orbiter's breakup and activated their emergency oxygen supplies. Indeed Pilot Michael Smith - in a valiant but hopeless attempt to gain control of the situation - had been working the control panel, activating switches in an apparent attempt to restore electicity after the breakup. Because of these discoveries many experts now believe that at least some of the crew members survived the entire 2 minute 45 second free fall to the ocean's surface and that it was that impact with the water - at 207 mph - that was the likely cause of death, not the explosion or orbiter's initial breakup.

In the aftermath of the Challenger disaster the Shuttle program was grounded for 31 months while changes to the decision making culture at NASA as well as new, more robust safety procedures were implemented.

The crew of STS-51L were: Dick Scobee, Michael J. Smith, Greg Jarvis, Judith Resnik, Ronald McNair, Ellison Onizuka and Christa McAuliffe.