STS-51-L

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STS-51-L was the twenty-fifth flight of the American Space Shuttle program, which marked the first time a civilian had flown aboard the Space Shuttle. The mission used Space Shuttle Challenger, which lifted off from Launch Complex 39-B on January 28, 1986 from Kennedy Space Center, Florida.

The mission ended in disaster following the destruction of Challenger 73 seconds after lift-off because of the failure of an O-ring seal on Challenger's right Solid Rocket Booster (SRB). The failure of the seal allowed a blow-torch like flare to impinge upon one of two aft SRB attach struts, which eventually failed, freeing the booster to pivot about its remaining attachment points. Subsequently, the forward part of the booster cylinder impacted the external tank (ET) intertank area, leading to a structural failure of the ET - the core structural component of the entire stack. A rapid burning of liberated propellants ensued. With the structural "backbone" of the stack compromised and breaking up, the SRBs flew off on their own, as did the orbiter, which rapidly disintegrated due to the overwhelming aerodynamic forces. Evidence later re-opened shows that one of the Oxygen Tanks carried by crew members in case of such a disaster had been activated, showing that one of the crew members may have been alive during the fall into the sea. If this is so, that crew member is likely to have died and/or disintegrated due to massive amounts of g-force, much like the orbiter which disintegrated due to huge amounts of overwhelming aerodynamic forces.

The tenth mission for Challenger, STS-51-L was scheduled to deploy the second in a series of Tracking and Data Relay Satellites, carry out the first flight of the Shuttle-Pointed Tool for Astronomy (SPARTAN-203)/Halley's Comet Experiment Deployable in order to observe Halley's Comet, and carry out several lessons from space as part of the Teacher in Space Project and Shuttle Student Involvement Program (SSIP). The flight also marked the first American manned mission to involve in-flight fatalities, and the first American manned mission to launch and fail to reach space, the first in the world being Soyuz 18a.

Crew

Francis "Dick" Scobee (2), Commander
Michael J. Smith (1), Pilot
Judith Resnik (2), Mission Specialist
Ellison Onizuka (2), Mission Specialist
Ronald McNair (2), Mission Specialist
Gregory Jarvis (1), Payload Specialist
Sharon Christa McAuliffe (1), Spaceflight Participant (Teacher in Space)

(1) number of spaceflights each crew member has completed, including this mission.

In the event McAuliffe was disqualified from flight, she would have been replaced by her NASA-selected backup, Barbara Morgan.

Mission objectives

Deployment of Tracking Data Relay Satellite-B (TDRS-B) with an Inertial Upper Stage booster
Flight of Shuttle-Pointed Tool for Astronomy (SPARTAN-203)/Halley's Comet Experiment Deployable
Fluid Dynamics Experiment (FDE)
Comet Halley Active Monitoring Program (CHAMP)
Phase Partitioning Experiment (PPE)
Three Shuttle Student Involvement Program (SSIP) experiments
Two lessons for the Teacher in Space Project (TISP).

None of the mission objectives were accomplished.

Mission parameters

Mass:

Orbiter Liftoff: 121 778 kg
Orbiter Landing: 90 584 kg (planned)
Payload: 21 937 kg

Perigee: ~285 km (planned)
Apogee: ~295 km (planned)
Inclination: 28.45° (planned)
Period: ~90.4 min (planned)
Duration: 73 seconds (6 days 0 hours 34 minutes planned)

Mission insignia

The STS-51-L crewmembers designed the insignia seen above to represent their participation in NASA's mission aboard Challenger, depicted launching from Florida and soaring into space to carry out a variety of goals. Among the prescribed duties of the five astronauts and two payload specialists (represented by the seven stars of the US flag) was observation and photography of Halley's Comet, backdropped against the U.S. flag in the insignia. Surnames of the crewmembers encircle the scene, with the payload specialists being recognized below. Surname of the first teacher in space, Christa McAuliffe, is followed by a symbolic apple.

External link

Report of the Presidential Commission on the Space Shuttle Challenger Accident