Explosive Decompression - Emergency Breathing Techniques
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From: Cote d'Azur
Explosive Decompression - Emergency Breathing Techniques
In the absence of sufficient cabin altitude, and failure of supplemental oxygen, is there any case to be made for emergency breathing techniques?
Perhaps adapting those used by mountaineers ("grunt breathing", etc. See this article, or this one for instance.
Is any such training given in current civil or military operations
Perhaps adapting those used by mountaineers ("grunt breathing", etc. See this article, or this one for instance.
Is any such training given in current civil or military operations
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From: Leafy Suburbia - In the High towers
Emergency Breathing Techniques
what a way to go if you are going to draw a last breathe
TnT
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From: Down at the sharp pointy end, where all the weather is made.
If you're at a cabin altitude of FL250 or above, then all the breathing techniques in the world aren't going to prevent you losing consciousness in around 30 seconds. The only training for this situation is to get on to an oxygen supply within that 30 secs. The other part of the training is to ensure that you have that supply available, before embarking on the flight.
Cheers,
The Odd One
Cheers,
The Odd One
Joined: May 2002
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From: Downeast
Well's...let's considere it is minus 50 degrees or there about...the air is as about as thin as my wallet....and the airplane remains at cruise altitude until it runs out of fuel....
Just what are you going to grunt breathe at 34,000 feet?
Just what are you going to grunt breathe at 34,000 feet?
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From: Down at the sharp pointy end, where all the weather is made.
Just before this gets moved to a more sensible forum, TnT has a point, 'cept of course that I'd MUCH prefer to change the genders around in my case, or it would be definitely NOT the way I'd like to go!!!!!
The Odd One
ps why do these ladies always seek after a young chap to draw their last breath with? Who's going to look after us old'uns??
Oh, I see, no-one...
The Odd One
ps why do these ladies always seek after a young chap to draw their last breath with? Who's going to look after us old'uns??
Oh, I see, no-one...
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From: England
I think I read somewhere (senility kicking in chaps, help me out) that Everest has been conquered without the use of oxygen. The trick, I believe was to very slowly acclimatise yourself to the high altitude by spending time at several increasingly higher levels.
Therefore, you have the answer: spend 6 months gradually ascending the Himalayas before each flight!
Therefore, you have the answer: spend 6 months gradually ascending the Himalayas before each flight!
Greetings From Hell's Dark Heart
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From: The Emerald City
Been reading Jon Krakauer's book "Into Thin Air" about a major problem on an Everest expedition.
As I recall, even after acclimitization to the altitude, above some level (26,000' I think), your body starts consuming itself because of the low oxygen levels -- you start losing fat and muscle tissue and other stuff. Sounds like a whole bunch of no-fun.
Not to be morbid, but a sudden decompression might not be a bad way to go out -- a moment or two of panic, a realization that all the pretty women are now attached to men other than yourself, and then lights out.
Then you wake up in the line at the Pearly Gates, and St. Peter says, "go away, mate, your name is on Draper's list"
As I recall, even after acclimitization to the altitude, above some level (26,000' I think), your body starts consuming itself because of the low oxygen levels -- you start losing fat and muscle tissue and other stuff. Sounds like a whole bunch of no-fun.
Not to be morbid, but a sudden decompression might not be a bad way to go out -- a moment or two of panic, a realization that all the pretty women are now attached to men other than yourself, and then lights out.
Then you wake up in the line at the Pearly Gates, and St. Peter says, "go away, mate, your name is on Draper's list"
Last edited by john_tullamarine; 17th August 2005 at 13:50.
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From: Planet Tharg
You could always hold your breath if you have advance warning.
...Of course, this may lead to a Mr Creosote impression you certainly won't enjoy.
You with the penguin.....! Yes, you!....... Why are you stalking me? 
...Of course, this may lead to a Mr Creosote impression you certainly won't enjoy.
You with the penguin.....! Yes, you!....... Why are you stalking me?
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From: Minnesota
From a currant thread in the Questions Forum:
Oxygen vs Altitude
My question relates to the emergency oxygen facility of an airliner (or any high altitude pressurised aircraft). My understanding so far, is that as altitude increases, pressure reduces, but the level of oxygen in the air remains the same. Therefore, because of the reduction in pressure, our bodies cannot absorb oxygen very well and thus we can get hypoxia.
So, when the oxygen masks are deployed (in an emergency) with a supply of oxygen, how can this help us to breathe if the outside pressure is still too low? Does it have something to do with the pressure of the oxygen chamber which goes over your mouth?
Thanks pruners,
Maz
But:
If oxygen remains at the same level (20%) as altitude increases then why do I have to lean my piston engine to correct the air fuel ratio? I mean as altitude increases, the engine breathes less air, because it is less dense, and as the carburetor dispenses fuel based upon the mass of airflow, then because the mass flow is lower it will dispense less fuel, automatically correcting the air fuel ratio.
Or am I being very dense myself…
Regards,
White Bear.
Oxygen vs Altitude
Oxygen vs Altitude
My question relates to the emergency oxygen facility of an airliner (or any high altitude pressurised aircraft). My understanding so far, is that as altitude increases, pressure reduces, but the level of oxygen in the air remains the same. Therefore, because of the reduction in pressure, our bodies cannot absorb oxygen very well and thus we can get hypoxia.
So, when the oxygen masks are deployed (in an emergency) with a supply of oxygen, how can this help us to breathe if the outside pressure is still too low? Does it have something to do with the pressure of the oxygen chamber which goes over your mouth?
Thanks pruners,
Maz
But:
If oxygen remains at the same level (20%) as altitude increases then why do I have to lean my piston engine to correct the air fuel ratio? I mean as altitude increases, the engine breathes less air, because it is less dense, and as the carburetor dispenses fuel based upon the mass of airflow, then because the mass flow is lower it will dispense less fuel, automatically correcting the air fuel ratio.
Or am I being very dense myself…
Regards,
White Bear.
Oxygen vs Altitude
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From: ball gazing
In the absence of sufficient cabin altitude, and failure of supplemental oxygen, is there any case to be made for emergency breathing techniques?
...as someone who has (deliberately) come off oxygen at 25,000 cabin altitude in an aircraft - momentarily - let me tell you that the first thing you will do is cough uncontrollably like a 200 a day addict....
....emergency breathing techniques? Don't think so....
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From: Canada
Drapes,
"A sudden lung full of even very thin air at -40 degree can't do much good either."
I'd agree about the "Thin" but the -40, although bracing, actualy seems not to have too much permanent effect as any one who has spent time in the far frozen North of Canada can tell you, through experience. Just don't freeze any of your bits.
"A sudden lung full of even very thin air at -40 degree can't do much good either."
I'd agree about the "Thin" but the -40, although bracing, actualy seems not to have too much permanent effect as any one who has spent time in the far frozen North of Canada can tell you, through experience. Just don't freeze any of your bits.
Hmmmyeah
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From: Leopardess.
[Sorry, off topic post.]
White Bear,
There are many other variables caused by changes in air density with altitude, and hence its compressibility and other factors in the inlet tract, but, in very rough terms, the carburetor does not so much read air mass as air velocity.
The pressure drop this velocity creates as it passes through a venturi in the inlet tract serves to siphon fuel from the float chamber into the inlet air stream.
Obviously the element in the air required in combustion is oxygen, which decreases in abundance, for any given volume of air through that signal venturi, with altitude.
The volume of air, more a less, being a constant of the pumping efficiency of the engine maintains a more linear siphon effect on the fuel than is required resulting in the mixture becoming over rich, hence you lean the mixture to compensate.
By no means the best example, as it's more concerned with design inefficiencies than principle, but take a look here (some way down the page) for a little more insight. (Sorry, only made a very brief search for an example and this certainly isn't the best, previous or subsequent pages may be more relevant possibly.)
Edit to add: Here's a better link. Scroll down a good way to a section sub-headed 'Mixture Control'.
White Bear,
There are many other variables caused by changes in air density with altitude, and hence its compressibility and other factors in the inlet tract, but, in very rough terms, the carburetor does not so much read air mass as air velocity.
The pressure drop this velocity creates as it passes through a venturi in the inlet tract serves to siphon fuel from the float chamber into the inlet air stream.
Obviously the element in the air required in combustion is oxygen, which decreases in abundance, for any given volume of air through that signal venturi, with altitude.
The volume of air, more a less, being a constant of the pumping efficiency of the engine maintains a more linear siphon effect on the fuel than is required resulting in the mixture becoming over rich, hence you lean the mixture to compensate.
By no means the best example, as it's more concerned with design inefficiencies than principle, but take a look here (some way down the page) for a little more insight. (Sorry, only made a very brief search for an example and this certainly isn't the best, previous or subsequent pages may be more relevant possibly.)
Edit to add: Here's a better link. Scroll down a good way to a section sub-headed 'Mixture Control'.
Last edited by SyllogismCheck; 16th August 2005 at 18:36.
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From: The Roman Empire
Chatting with a colleague today he said your blood will start to boil at 34000ft, so even if you wear an oxygen mask you won't survive the sudden decompression.
I told him this is not true, at worst you'll feel some bends...
Anybody able to confirm?
I told him this is not true, at worst you'll feel some bends...
Anybody able to confirm?
