Posted on Mar 12, 2014
What were doing on January 28th, 1986 when the the Space Shuttle Challenger exploded on takeoff?
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I was sitting around the table at the DFAC tonight here at Camp Arifjan Kuwait when the topic of the Space Shuttle Challenger came up. I had to laugh when one of the guys told me he wasn't even born yet. I was a Senior in High School in DeLand Florida at the time. I went outside and could see the smoke trails from where the Challenger had come apart. What is your memory of the event?
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I was a guest observer at the launch, listening to cap com and eng nets, throwing up, and on the phone to iTek to expedite the frame by frame enhancement of tracking camera footage.
By the evening, the iTek enhancement showed solid rocket booster burn through (hot propellant exhaust through the skin of the booster). But, it took much longer time for Feynman Committee to determine the problem originated from thermal expansion and contraction damage to the key O-Ring seals between the solid rocket motor segments.
Note dark grey smoke from SRB on ground and bright secondary plume from SRB in flight.
This was a devastating personal loss for NASA, survivors, contractors, and the nation.
CH (MAJ) (Join to see)
Sandy… unbelievable! I can't imagine the trauma that you and everyone else who where at the launch site experienced that morning. My heart goes out to you and everyone else that where there that day. Thanks for sharing the images. I have never seen the one with the grey smoke while still on the ground. Thanks for helping us all have an inside view of this tragedy!
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Disintegration of the entire vehicle began after an O-ring seal in its right solid rocket booster (SRB) failed at liftoff. The O-ring failure caused a breach in the SRB joint it sealed, allowing pressurized hot gas from within the solid rocket motor to reach the outside and impinge upon the adjacent SRB attachment hardware and external fuel tank. This led to the separation of the right-hand SRBs aft attachment and the structural failure of the external tank. Aerodynamic forces promptly broke up the orbiter.
Feynman Committee (Rogers Commission) Key Launch Details:
At T+72.284, the right SRB pulled away from the aft strut attaching it to the external tank. Later analysis of telemetry data showed a sudden lateral acceleration to the right at T+72.525, which may have been felt by the crew. The last statement captured by the crew cabin recorder came just half a second after this acceleration, when Pilot Michael J. Smith said “Uh oh.”
At T+73.124, the aft dome of the liquid hydrogen tank failed, producing a propulsive force that pushed the hydrogen tank into the liquid oxygen tank in the forward part of the ET. At the same time, the right SRB rotated about the forward attach strut, and struck the intertank structure. This resulted in the spontaneous conflagration of the fuel in the external tank, creating a massive plume of water vapor exhaust that enveloped the entire stack.
The breakup of the vehicle began at T+73.162 seconds and at an altitude of 48,000 feet (15 km). With the external tank disintegrating (and with the semi-detached right SRB contributing its thrust on an anomalous vector), Challenger veered from its correct attitude with respect to the local air flow and was quickly torn apart by abnormal aerodynamic forces, resulting in a load factor of up to 20 (or 20 g), well over its design limit of 5 g.
The more robustly constructed crew cabin and SRBs survived the breakup of the launch vehicle. The detached cabin continued along a ballistic trajectory, and was observed exiting the cloud of gases at T+75.237. Twenty-five seconds after the breakup of the vehicle, the trajectory of the crew compartment peaked at a height of 65,000 feet.
Conclusion: The Space Shuttle was never certified to operate in the 18 degree temperatures of the morning of the launch. The O-rings, as well as many other critical components, had no test data to support any expectation of a successful launch in these conditions.
Bob Ebeling from Morton Thiokol delivered a biting final analysis: “[W]e’re only qualified to 40 degrees …‘what business does anyone even have thinking about 18 degrees, we’re in no man’s land’”.
Full Report: http://history.nasa.gov/rogersrep/genindex.htm
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