STS-51-L

For more on the accident, see Space Shuttle Challenger disaster.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 pad 39B on 1986-01-28 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.
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For further information about Challenger's mission and crew, see STS-51-L. 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.
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