Originally Posted by
vitira
I mean … there are 54 peaks in Colorado >14k ft which people climb without oxygen. Useful consciousness there can be forever, depending on the person.
Climbing a peak is not the same as sudden decompression. Your body has time to acclimatize when you are climbing a mountain. When the cabin of an aircraft loses pressurization, your body effectively is going from 6-8k feet to whatever the external altitude is within 1-2 seconds.
Originally Posted by
DenverBrian
Some Coloradans live every day at over 10,000 feet. Trail Ridge Road in Rocky Mountain National Park is at 12,000 feet. @:-)
Again, those people are acclimatized, not experiencing a rapid decompression. The human body can acclimatize up to ~8,000m, but it takes months to achieve this. A sudden decompression to 14k feet gives around 30 mins of useful consciousness.
Originally Posted by
timfountain
As you likely know, at max cruise altitude (above 35k ft.) one of the pilots SHOULD be wearing an O2 mask full time as per FAR 91.211. It's a well know fact that this is one of the most disregarded rules in the aviation industry. But this episode is there to remind us why that rules exists....
There's an exemption for quick deploying masks. Really, the most sinister type of decompression is when there is a bleed valve issue or something similar, where the pilots slowly lose situational awareness due to hypoxia. This is what killed Payne Stewart and what happened with the Helios flight in 2005. The pilots will set an altitude in the autopilot and slowly become hypoxic, which makes it even harder for them to identify that there is an issue.