Tuesday, December 30, 2008

NASA report on Columbia crew is out

NASA's Spacecraft Crew Survival Integrated Investigation Team has published its report, available at:
http://www.nasa.gov/reports
The report on lessons learned from Columbia states that the crew was incapacitated almost immediately from decompression, without even time to lower their helmet visors. As NASA PAO describes the report, "The team's final report includes 30 recommendations to improve spacecraft design and crew safety. The recommendations cover a broad range of subjects from crew training, procedures, restraints and individual safety equipment to spacecraft design methods and recommendations regarding future accident investigations."

COMMENT: One recommendation (already put into effect) is that Shuttle crews be trained to activate personal breathing systems and close visors at the first sign of a problem. I'm missing something here. Why are crews not required to be in fully pressurized suits, visors down and sealed, with an independent air supply, during every reentry?

UPDATE:

It was pointed out to me that the report says:

"The launch and entry suit was added in response to the Challenger accident, rather than as a part of the original vehicle design. The ACES was the successor to that suit. The suit protects the crew in many scenarios; however, there are several areas where integration difficulties diminish the capability of the suit to protect the crew. Integration issues include: the crew cannot keep their visors down throughout entry because doing so results in high oxygen concentrations in the cabin; gloves can inhibit the performance of nominal tasks; and the cabin stow/deorbit preparation timeframe is so busy that sometimes crew members do not have enough time to complete suit-related steps prior to atmospheric entry."

Granted, the engineering changes for a mod like this will not be attempted now, with the shuttle scheduled for retirement, but the oxygen level problem could be fixed by a tweak to environmental control system (making it, essentially, run slightly less efficiently during the last hour of flight), the timeline adjusted a few minutes to permit the additional suit-related steps, and, as to the gloves, the gloves of the ACES suit, like all pilot/astronaut pressure suits, are specifically designed to permit use of the control stick and other critical controls while fully pressurized. The crew's actions would be less efficient, but not prohibited.

I know the folks who did this report and the CAIB and Challenger ones are infinitely more qualified than I am, but I'm still missing the logic here.

ANOTHER UPDATE: I posted this comment on NASAWatch, and Shuttle Program Director Wayne Hale took the time to respond and note that my suggested setup is not possible with the environmental control system built into the Shuttle, but will be possible with Orion. Thanks, Wayne.

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