Quote:
Originally Posted by Donger
The truly horrible part is that we know that some of the crew survived the disintegration, and may have actually died on impact with the Atlantic, two minutes after the malfunction.
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From WIKI, Jesus Christ, what a way to go.
Cause and time of death
The shuttle was designed to withstand a load factor of 3 (or 3 g), with another 1.5 g safety factor built in.[13] The crew cabin in particular is a very robust section of the shuttle because of its design and construction of reinforced aluminum.[13] During vehicle breakup, the crew cabin detached in one piece and slowly tumbled into a ballistic arc. NASA estimated the load factor at separation to be between 12 and 20 g; however, within two seconds it had already dropped to below 4 g and within ten seconds the cabin was in free fall. The forces involved at this stage were likely insufficient to cause major injury.
Astronauts from a later Shuttle flight (STS-34) stand next to their PEAPs
At least some of the astronauts were likely alive and briefly conscious after the breakup, as three of the four Personal Egress Air Packs (PEAPs) on the flight deck were found to have been activated. Investigators found their remaining unused air supply roughly consistent with the expected consumption during the 2 minute 45 second post-breakup trajectory.
While analyzing the wreckage, investigators discovered that several electrical system switches on Pilot Mike Smith's right-hand panel had been moved from their usual launch positions. These switches were protected with lever locks that required them to be pulled outward against a spring force before they could be moved to a new position. Later tests established that neither force of the explosion nor the impact with the ocean could have moved them, indicating that Smith made the switch changes, presumably in a futile attempt to restore electrical power to the cockpit after the crew cabin detached from the rest of the orbiter.[14]
Whether the astronauts remained conscious long after the breakup is unknown, and largely depends on whether the detached crew cabin maintained pressure integrity. If it did not, the time of useful consciousness at that altitude is just a few seconds; the PEAPs supplied only unpressurized air, and hence would not have helped the crew to retain consciousness. The cabin hit the ocean surface at roughly 207 mph (333 km/h), with an estimated deceleration at impact of well over 200 g, far beyond the structural limits of the crew compartment or crew survivability levels.[11]
“Scob fought for any and every edge to survive. He flew that ship without wings all the way down....they were alive”
Robert Overmyer, NASA Lead Investigator[13]
On July 28, 1986, Rear Admiral Richard H. Truly, NASA's Associate Administrator for Space Flight and a former astronaut, released a report from Joseph P. Kerwin, biomedical specialist from the Johnson Space Center in Houston, relating to the deaths of the astronauts in the accident. Kerwin, a veteran of the Skylab 2 mission, had been commissioned to undertake the study soon after the accident. According to the Kerwin Report:
The findings are inconclusive. The impact of the crew compartment with the ocean surface was so violent that evidence of damage occurring in the seconds which followed the disintegration was masked. Our final conclusions are:
the cause of death of the Challenger astronauts cannot be positively determined;
the forces to which the crew were exposed during Orbiter breakup were probably not sufficient to cause death or serious injury; and
the crew possibly, but not certainly, lost consciousness in the seconds following Orbiter breakup due to in-flight loss of crew module pressure.[11]
Some experts, including one of NASA's lead investigators Robert Overmyer, believed most if not all of the crew were alive and possibly conscious during the entire descent until impact with the ocean.[13]