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cheezyflier
November 6th, 2008, 08:48
ok, so maybe this is a dumb question but try not to laugh too loud.
i can handle polite snickering :icon_lol:

anyhow i was checking out some specs on the 206 and also the mooney bravo. they both seem capable of far greater altitude than i have ever flown them in fsx. ok... ready for the question?

how does one breathe up there at that altitude in planes like that? i know how it's done in a tubeliner, but what about the g/a stuff that's capable of over 15k ft?

Big_Stick
November 6th, 2008, 08:56
ok, so maybe this is a dumb question but try not to laugh too loud.
i can handle polite snickering :icon_lol:

anyhow i was checking out some specs on the 206 and also the mooney bravo. they both seem capable of far greater altitude than i have ever flown them in fsx. ok... ready for the question?

how does one breathe up there at that altitude in planes like that? i know how it's done in a tubeliner, but what about the g/a stuff that's capable of over 15k ft?

Take along a small portable supply of supplemental oxygen, available through any pilot shop.

luckydog
November 6th, 2008, 09:35
I don't usually fly that high 'cause I'm scared of heights, but when I do I just hold my breath.......

cheezyflier
November 6th, 2008, 12:40
I don't usually fly that high 'cause I'm scared of heights, but when I do I just hold my breath.......

what happened to your lipstick?

tigisfat
November 6th, 2008, 12:52
I don't usually fly that high 'cause I'm scared of heights, but when I do I just hold my breath.......

there's nothing wrong with breathing the air up there....It's not like it's toxic. At the minimum you'll get more oxygen than holding your breath.

It all depends on the person. I regularly fly up to the low teens in unpressurized aircraft out here in texas. I don't get hypoxic easy, but I also run five miles 3 times a week and gave up smoking a long time ago. If you're in terrible shape and you smoke like Andrew Dice Clay you're likely to get hypoxic faster. The very act of lighting up a cigarette can ignite a 'fire' inside of you (speaking from experience now) and slowly pull a nearly unavoidable and incomprehensible gray-out over your eyes.

Like mentioned before, it's no problem to take supplemental oxygen in an unpressurized aircraft. It's too bad the air is thin up there, because it's so clean feeling to breathe it's amazing.

luckydog
November 6th, 2008, 12:54
what happened to your lipstick?

The "party's" over :crybaby:......

Lionheart
November 6th, 2008, 16:01
Some planes even come with a linkage plumbing system for oxygen. Just fill the bottle / tank and fit it in the place it is to go, plug it in, plug in the oxy masks at the proper time into the oxy sockets located at each seat position, and you are set. Some aircraft also feature a low oxygen alert alarm so if you are climbing up there and forget to activate the oxygen, it will let you know.

Some things that happen with low oxygen to the brain is headaches, disorientation of up, inability to concentrate, breakdown in cognisence, such as which way is left, what direction to flip a switch on, etc. Then, you fall asleep if you dont figure out what to do, (lose altitude fast, or put on the oxygen if you have it).

I have heard people that flew Vikings and Socata Trinidads of how they would take trips and climb up to absolute max altitude the craft could go, and they would see up close the airliner traffic. I wonder what it was like for an airliner crew to see a Viking or Trinidad go past, lolol.. :d



Bill

PS: LuckyDog.. That photo just doesnt look right anymore without the lipstick...

srgalahad
November 6th, 2008, 16:29
and there's the legalities involved that pilots are supposed to comply with...

Flight above 10,000 ft . max 30 minutes without supplementary O2
Flight above 13,000 ft supplementary O2 required for all crew and passengers

which is why the old air routes across the Rockies were so dang scary


Bill,
"I wonder what it was like for an airliner crew to see a Viking or Trinidad go past, lolol.."
probably not quite as amazing as being in a tube cockpit at FL290 and being told traffic was a sailplane, 10 o'clock, 4 miles at FL 310. More fun when both pilots discovered they knew each other. :mixedsmi:

jmig
November 6th, 2008, 16:36
and there's the legalities involved that pilots are supposed to comply with...

Flight above 10,000 ft . max 30 minutes without supplementary O2
Flight above 13,000 ft supplementary O2 required for all crew and passengers

which is why the old air routes across the Rockies were so dang scary


Bill,
"I wonder what it was like for an airliner crew to see a Viking or Trinidad go past, lolol.."
probably not quite as amazing as being in a tube cockpit at FL290 and being told traffic was a sailplane, 10 o'clock, 4 miles at FL 310. More fun when both pilots discovered they knew each other. :mixedsmi:

You beat me to it. LOL I never have forgotten the audio tape they played for us in pilot training. It was of a F-100 pilot who was hypoxic. He laughed and joked all the way to the ground where it ended mid laugh.

It does something to you when you hear a real tape like that one. Hypoxia is nothing to fool around with. Evey three years we had to take an altitude chamber ride where we got hypoxic so we could recognize the onset.

SirBenn21
November 6th, 2008, 17:59
Glider pilots use standard medical oxy cylinders all the time.
It was one of our pre-flight checks at my old club.

Here is a link of the guys that do it in an extreme way.

http://www.perlanproject.com/

I remember a guy in South Africa that got to 46000 ft and almost died from the cold. He only had a track-suit and wind breaker on to fight the elements!

cheezyflier
November 6th, 2008, 19:10
i know it probably sounds funny but all this time i have been staying under 10k ft in my small g/a planes and the dc-3 because i didn't know the answer to this. i kept meaning to ask, but i would come here and get distracted by everything else going on here. :costumes:

djscoo
November 6th, 2008, 19:15
RAF training cartoon about Hypoxia
PUHlUkz-CdI

N2056
November 6th, 2008, 19:36
Here's an example of what is called a 'nasal cannula' that I modeled for Lionheart's FSX Viking. When you click on the oxygen valve in the vc this appears :d

60885

limjack
November 6th, 2008, 19:43
OMG!......great topic...I never new this...I would not want to be a pilot with Hypoxia...game over and you would be done!!!
http://www.youtube.com/watch?v=qLQMupV3DLk

Jim

cheezyflier
November 7th, 2008, 06:01
OMG!......great topic...I never new this...I would not want to be a pilot with Hypoxia...game over and you would be done!!!
http://www.youtube.com/watch?v=qLQMupV3DLk

Jim

wow! that was really something!:isadizzy:

srgalahad
November 7th, 2008, 08:01
Most transport aircraft have "cabin altitude" set for 8000-8500 ft and it still has an effect on the body and brain (it's only a 'best compromise' of structure vs pressurization).
Lower O2 content also exacerbates the effect of alcohol and any respiratory disfunction gets worse. Most people don't know about hypoxia so a chest cold and a couple of drinks on a long flight can be dangerous.
Also, the mental impairment shown in limjack's UTube video explain a lot of the cases of 'air rage' .. the twits just don't comprehend instructions given by the crew (like "Sit down and shut up") any more than the aircrew trainee got the message to put on his mask.
One of the first signs is often visual impairment.. things like missing the "thousands" needle on an altimeter (misreading 22,000 as 12,000) or just not comprehending what is read.

jmig, I got the same F-100 tape played for me in training and I will NOT go there!

BTW, living at sea level all your life and then transitioning to a high altitude city (or ski hill!) can have a similar effect for a few days/weeks until you acclimatize.

..and then we could get into the really severe results but those are usually discussed after an autopsy :redf:

Lateral-G
November 7th, 2008, 08:46
Let's not forget most normally aspirated engines do not perform well above 14.5K

You need some sort of turbo or supercharger.

-G-

fliger747
November 7th, 2008, 09:53
The old Supercub has been up to 21,000'..... (yes still within 1200' of terrain) Not real perky up there as a normally aspirated engine, in essence the mixture control becomes the throttle above 15,000'.

In the 747 we are required to wear the O2 mask if the other pilot leaves his seat. Above 40,000' one has to wear the mask at all times. Though with the amazing volume of the 747 fuselage, depresurization is not likely to extremely rapid, but it is possible. At those altitudes unconciousness would be almost immediate. Not too much higher and very sophisticated oxygen breathing and pressure suits become necessary.

Numerous fighter aircraft were lost during WWII due to undetected failure of the O2 apparatus. On problem on longer flights was icing of the regulators etc.

Cheers: T.

EgoR64
November 7th, 2008, 14:39
:wavey:

Very Cool Vids, too high with no Oxygen is a bad thing !!

Cheers !! :ernae:

SkippyBing
November 7th, 2008, 15:17
I actually had a flick through an AvMed book recently, and at the heights passenger jets fly at e.g. 30000' if you do suffer complete de-pressurisation you've only got around 30-45 seconds to get the mask on before you suffer permanent damage/death. Much higher and it's down to <10 seconds, plus you have to use pressure breathing as the partial pressure of Oxygen isn't enough even at 100% O2.

Lionheart
November 7th, 2008, 15:22
Man....! 10 to 30 seconds!! That cant be good.

Thats like being in a submarine, running out of oxygen, deep under the sea, and you have to surface emmediately. For a small plane at that altitude, even in a dive, you would take a short while to get to 10,000 feet.

You would think people could last 3 min's unconcious with the air in their blood sustaining them. Does the atmosphere suck it out of them or something?

Skeeeeery....



Bill

SkippyBing
November 7th, 2008, 15:45
Due to it being a medical text book I'm not 100% sure on the mechanics (On a good day I have an engineering degree but it's been a few years since I used it in anger), but I don't think it's the same as holding your breath. I.e. once you're unconscious you'll start to hyperventilate due to the build up of CO2/lack of Oxygen which will only make the situation worse, similarly if you don't know you're about to lose the Oxygen supply you won't have the supply in your body to last that long. For instance to hold your breath for 3 minutes you'll generally want to do a few deep breaths before hand.
I've also got a sneaky feeling the drop in pressure doesn't help.
Personally I can't remember the last time I went above 3000' in an unpressurised airplane so it's less worrying!