For technical aspect/debate of cabin depressurization, read this thread:
http://www.freerepublic.com/focus/f-news/1463039/posts
One gent had a particularly interesting point:
#120:
To: leadpenny
Maybe, but something smells bad about this. Commercial pilots are trained, trained, and trained again what to do in this kind of situation. They've got oxygen masks immediately handy, and in the 737 they've got a gauge handy that shows them the relative altitude of the cabin (what altitude the cabin pressure is simulating), what the differential is between outside and inside, and they've also got alarms that go nuts if the cabin altitude goes over a certain figure.
If those alarms go off, they immediately call ATC, declare an emergency, and descend to under 14,000 feet as quickly as possible, which would take several minutes from 30,000+ feet. The oxygen masks have to be able to be donned in just a few seconds, and pilots practice it every year in training.
Also, a commercial jetliner is going to be flying about 10,000 feet lower than Stewart's jet was (I think he was up at FL450, 45,000 feet), which *should* extend the time of useful consciousness enough to let them at least call ATC and declare the emergency, and start down.
In order for something like this to happen I think two separate things have to go wrong--there has to be a pressurization failure somewhere on the airplane, *and* the backup oxygen systems, which use chemical generators (like what brought down that Valujet DC-9 in the Everglades), have to fail. If both of those happened, then yes, the pilots and passengers could conceivably pass out before the plane reached breathable altitudes. But, they *should* come back around when it does. Now, will they come back to consciousness in time to stop the plane from hitting the ground? Maybe, maybe not.
Something really, really, smells here. Especially since one news article mentions that a passenger text-messaged a relative before the crash that the pilots were unconscious. If true, that means the cabin had pressure, but the pilots were still unconscious or dead? Very fishy.
BTW, I'm not a pilot, just a wannabee and flight-sim geek. We need some real pilots in here to clarify.
}:-)4
That was me that posted that, and I've been rooting around for information in other places; take it with a grain of salt, but other postings I've seen on other boards indicated that the escorting F-16s may have seen oxygen masks deployed (indicating depressurization) and that either the F-16 pilot, or a passenger--I've heard both versions--reported that the pilot's face was "blue".
It almost certainly wasn't a bomb, because the plane flew along at cruise altitude for some period of time, probably on autopilot, with no visual damage that the escorting fighters could see and no contact with air traffic control, hence the fighters. So Occam's Razor says that it's a pressurization problem (which would also explain the "frozen" bit...it's pretty darn cold up there at 34,000 feet). But pilots are trained in what to do when that happens, and there's two of them up in the front of that 737. And if the cabin pressure alarms go off, the first thing they're supposed to do is put on their own masks...the second is to get the airplane the hell down to 14,000 feet or lower as fast as they safely can. EVERYTHING else is secondary, because at those altitudes, hypoxia will turn anybody into a blithering idiot in mere seconds, and knock them out cold seconds after that.
It may not be terrorism. It may just be a mechanical failure compounded by pilot error. I seriously doubt it was a 9/11-style hijack, or a bomb; if there was foul play involved, my SWAG is that it would have to have been on the maintenance side. But we won't know until the investigators get to the crash and start digging through the wreckage.
All we know for sure right now is that a helluva tragedy just went down.
}:-)4
I'm a pilot, and everything that you wrote makes sense.
I'm waiting for some more clarity from the authorities before assuming anything more, but the news points reported don't make sense when taken together.
We need some real pilots in here to clarify.
Well stated post by that guy.
Unlike that poster I am a pilot, a retired fighter pilot, as well as a USAF trained Life Support Officer that was trained at Kelly AFB and Brooks.
Mechanical failure if back-up Oxygen systems are there in case of emergency. The issue is one of mechanical reliability and an aircrew’s ability to react in a timely manner.
Mechanical reliability of systems rarely ever deployed is problematic and involved regular maintenance checks, which by the way, do add a human error element in the reliability of the system. Also, we are talking a foreign maintenance program. Foreign maintainers are notorious for their lack of reliability and safety practices. Indeed, Cypress is ranked very low for maintenance practices and safety.
As far as the aircrew reacting, if the warning are not present they do have a cabin altimeter they can reference, but here is the thing: A reliance on the back-up system and warning systems does lead to complacency and complacency will affect their discipline to actually read the gauge. Of course, in a climb you reference the gauge to make sure cabin pressurization is working, and that is usually done when climbing through 10,000 feet. If it looks good at that time you rely more on the bells and whistles rather than the gauge.
Now, if the pilots succumbed to Oxygen deprivation (hypoxia) due to a slow leak, the discovery of their hypoxia symptoms may be slow in coming. . .too slow to discover. They would slowly, and without really noticing, pass out.
With rapid decompression the effects are felt (and usually heard) and see and reacted too. TUC, (time of useful consciousness) varies with altitude. At FL35 I think it is around 20 secs to react, with less time if higher and more time if lower.
So, if the aircraft experienced rapid decompression the aircrew would have known and reacted quickly, and if the cockpit oxygen back-up system was still functioning, they would have survived.
If the hypoxia were due to a slow leak then they would have passed out not knowing what was happening. Of course, as the aircraft descended to a lower altitude the aircrew would recover, but they recovery is not like you see in movies. There is not magic moment of awakening. . it is a wakening where the aircrew are confused and unsure and groggy. If there is enough time then they may recover fully to save the jet, if not, they die.
Right now we simply don't know what happened. We have no facts, no flight data recorder, and we certainly have no survivor from the cockpit to tell us what happened.
The supposed text message is interesting in that the guy that sent the text was likely metabolically more fit than others and that might explain the message.
Anything else right now is guesswork only, and I as, irresponsible.
Now, for real, I'm outta here.
It is indeed "fishy".Could they have been drugged?
Check out the article on http://www.theaustralian.news.com.au/common/story_page/0,5744,16262302%255E601,00.html
Paragraph #16
"Citing Larnaca airport sources, it reported that the plane had called technicians to repair problems with its communications and cabin pressure systems before take-off."
Pilots are trained to radio for help when needed. This whole thing stinks.
A possibility here:
Maybe the pilot had ALREADY LEFT HIS SEAT inorder to explore some solution when the reason/need to don the oxygen appeared...such that he was caught unawares (out of his seat, out of reach of the oxygen mask).
He MIGHT have left his seat to try to repair or remedy whatever might have been a problem, is my point, and THEN the emergency that prompted donning the oxygen mask occured.
That would explain the pilot not being in his seat, not being in the cabin (I haven't read if he was IN the cabin or not, just that he was not in his seat), and if that event then occured, the copilot would be as was wearing his oxygen mask and in the cabin but unconscious...with others trying to wrestle the plane under control.
I think there's not yet enough information to speculate about the various positions the crew and cabin crew were seen to be in from the F-16's.
Cold has been mentioned, but telephone keypads don't work very well below 20 degrees F or so. I used to have to put my handset on the defroster (bag phone) in the winter to get it warm enough to work. (older van, more space than heat).
the "receipient" of that "message" has been arrested and has admitted thathelied about receiving it.