2009/01/09

Voyage Of The Doomed

NASA Releases Details On Deaths Of Columbia Crew

In a newly released research from NASA, it is revealed the astronauts had no chance of surviving the critical mishap that befell Columbia.
The last seconds of the astronauts aboard the doomed Columbia space shuttle have been described in graphic and harrowing detail by Nasa after a four-year investigation into the 2003 disaster.

The 400-page report reveals that they had no more than 40 seconds to react — not long enough to seal their suits and avoid blacking out from hypoxia, a condition said to be similar to extreme alcoholic intoxication.

None of the crew of seven had a helmet visor closed during re-entry into the Earth’s atmosphere over Texas on February 1. One was not wearing a helmet, and three were not wearing the gloves that came with their orange pressure suits. This was a response to a design flaw with the suits — if the astronauts kept their helmet visors closed it allowed too much oxygen to build up in the cabin, and the gloves were too bulky to allow them to operate the spacecraft’s controls.

The crew members, returning from a 16-day mission, would have lost consciousness almost immediately after superheated gases entered a small ragged hole in the shuttle’s left-wing heat shield — caused by a briefcase-sized chunk of foam from the external fuel bank breaking off 81.7 seconds after lift-off. The gas melted the spacecraft’s frame, sending it into an uncontrollable spin at 203,000ft and 12,500mph. Moments later the nose section — where the crew were seated — broke away from the fuselage.

The nose cone began to break up in the intense heat of re-entry, causing a violent cabin decompression. If the decompression alone did not kill the astronauts, the violent shaking and spinning of the nose section probably did, because they were not property restrained in their seats. According to the report: “The inertial reel mechanisms on the crews’ shoulder harnesses did not lock . . . As a result, the unconscious or deceased crew was exposed to cyclical rotational motion while restrained only at the lower body.” It added that “crew helmets do not conform to the head . . . consequently, lethal trauma occurred to the . . . crew due to the lack of upper body support and restraint”.

The last words from the stricken spacecraft came at 8.59am, when commander Rick Husband said: “Roger, uh, buh . . .” as alarms began to go off in the cabin simultaneously. A minute later the nose section had fallen to 137,000ft. Within the next 24 seconds it was destroyed. The report concludes that even if the harnesses and suits had been working perfectly, the accident would have been unsurvivable, because ultimately the crew members, practically torn in half by their lap belts, were thrown out of the nose section into superheated, near-vacuum conditions. It goes on to make 30 recommendations for improving crew safety. “I call on spacecraft designers from all the other nations of the world, as well as the commercial and personal spacecraft designers here at home to read this report and apply these hard lessons, which have been paid for so dearly,” said Wayne Hale, a Nasa associate administrator.

“This report confirms that although the valiant Columbia crew tried every possible way to maintain control of their vehicle, the accident was not ultimately survivable.”

I guess that covers that.

One of the things that prompted me to start blogging was actually the aftermath of the Columbia disaster. I think it kind of hit me that for years NASA had been doing the shuttle program only to have lost 2 of a fleet of 5 shuttles, while accomplishing relatively little, even when compared to the Apollo program. In the years since then, we've all come to understand that perhaps the concept of the shuttle was always a little sketchy, and all the technical problems it contained led to both the Challenger and Columbia disasters.

In a nutshell, they are the most complicated machines ever built by mankind, which means that it has the most parts that can fail. The effect of any of the failed pieces of the shuttle can be absolutely overwhelmingly catastrophic, which in a sense accounts for both accidents. In response to the Columbia disaster, NASA grounded its fleet, and then 4 years ago, gingerly proceeded to continue with the flights. The fleet of shuttles will be retired in 2010, which is now less than 2 years away.

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