How do you lose a 777?

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http://flightsafety.org/hf/hf_may-jun97.pdf

"At very high alltitudes (45,000 feet) or higher even the use of 100 percent oxygen will not sustain conciousness because of the increased volume of water vapor and CO2 in the lungs, Above 33,000 feet to breathe normally, the lungs must be pressurized by some mechanical means"

 
http://flightsafety.org/hf/hf_may-jun97.pdf

"At very high alltitudes (45,000 feet) or higher even the use of 100 percent oxygen will not sustain conciousness because of the increased volume of water vapor and CO2 in the lungs, Above 33,000 feet to breathe normally, the lungs must be pressurized by some mechanical means"
I don't remember what school it was for but my husband had to take a test in-flight at some elevation with out oxygen... the test looked like something maybe a 1st grader may take and most of the people couldn't do it. (like "draw hands on the clock so it says 12:50" type questions)

EDIT- actually I think it was in a simulator now that I recall...

 
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Not the same but I can attest that breathing at 13,500 feet is difficult even if your not moving... Can't imagine if you doubled that....

 
A hypobaric chamber... that is what it is, and it was to show how poor your judgement and display how bad of a decision you may make with the lack of oxygen. That test is supposedly given at the equivalent to 25,000 ft off oxygen for just a min or two.

 
Not the same but I can attest that breathing at 13,500 feet is difficult even if your not moving... Can't imagine if you doubled that....
Anything sustained over 12,500 ft MSL in an aircraft requires oxygen. They allow temporary operation (max 30 minutes) up to 14,500.

A friend of mine got caught in an updraft that took him to about 17,000 feet before he could get clear of it. He was on the verge of passing out and remembers watching his finger tips start to turn blue.

 
I'll attest to that. I was the one that had the cabin depressurize and was headed into blackout before the pilot nose dived and had us skimming the ground on the way back to Orlando.

 
I usually cruise between 6,000 and 10,000 ft depending on winds. The service ceiling on mine is 17000 ft but I'm not sure my normally aspirated engine could actually haul the airframe up there. I've had it at 12500 a couple of times and it's pretty weak on power.

There's a turbo charger modification available for mine that will move the ceiling up to 25000 ft.

 
I summeted a 14er last summer, meaning that I have been higher above sea level than your airplane has.

 
That's getting up there. Pike's Peak is just over 14k elevation.

 
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I summeted a 14er last summer, meaning that I have been higher above sea level than your airplane has.
Great, now I'm gonna have to go out and take it up to 14.5 just to see if it will do it. I'm too lazy to borrow an oxygen bottle to see just where it stops.

 
You can do 14k without oxygen, no problem - you might get a little dizzy, or a bit of a headache.

I've been there, Dex!

Back on subject, I am beginning to suspect that the plane may never be found. Just two more weeks until the black box stops emitting. I heard on CNN this morning (so take that for what' it's worth) that the pings it emits are only audible within about 2 miles. So does that mean you couldn't even hear it from the surface directly above, in waters deeper than about 11,000 ft???

My prediction: this will be the Emilia Earhart mystery of the entire 21st century.

 
^I thought they could be heard for 5 miles but that still makes it a pretty small circle when you consider the size of the search area.

 
Flyer, do you know why plane data is still stored in black boxes instead of being transmitted to a server off of the plane?

 
^^^

For older planes I'd guess it cost to much, these days that probably isn't as much of an issue but the standard practice is still to put the box in the plane.

Have they ever not recovered a black box? I know they were worried about it when that Air France flight went down in the Atlantic in 2009(?). Eventually they found it, but he search area was no where near as large.

 
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Flyer, do you know why plane data is still stored in black boxes instead of being transmitted to a server off of the plane?
I think the technology for transmitting that much data from a flying aircraft isn't quite there yet. I think things are heading that way though as evidenced by the data feeds received by the engine manufacturer.

I don't know if they will ever totally eliminate the black boxes but I think the ability to transmit all of the relevant data in nearly real time isn't very far off. It will be interesting to see how fast it gets adopted.

 
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