How often do plane stowaways fall from the sky?
bbc.co.uk
bbc.co.uk
Even with a canister of oxygen, at 35,000 feet you can't breath if you aren't in a pressure suit. Just doesn't work that way.
Even with a canister of oxygen, at 35,000 feet you can't
breath if you aren't in a pressure suit.
"At 18,000ft (5,490m), experts say, hypoxia will set in, causing weakness, tremors, light-headedness and visual impairment...Above 33,000ft (10,065m) the lungs require artificial pressure to function normally."
Above 33,000ft (10,065m) the lungs require artificial
pressure to function normally.
So I wouldn't count on the canister alone, unless it is connected to a full-body suit.
Unsurprisingly, there is little data on this, but what there is seems to indicate that vacuum is survivable.see e.g. http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/970603.h..., http://www.newscientist.com/blog/space/2008/06/how-long-can-...
You can breath at 35,000 ft without a pressured suit, but go much higher and you can't.
At sea level, you have 760 mmHg of air pressure. Oxygen is 21% of the air mixture, so you have a partial O2 pressure of 160 mmHg.
At 35,000 ft, air pressure is 179 mmHg [1], so if you breath 100% pure oxygen, you're getting the same amount of oxygen you'd get at sea level.
Go up to 50,000 ft and the air pressure is only 83 mmHg, so even breathing 100% oxygen, you're only getting 50% of the oxygen you'd get at sea level.
[1] http://www.engineeringtoolbox.com/air-altitude-pressure-d_46...
Is there, perhaps, some reason why I can't? Lungs exploding because of the 1ATM pressure differential, for instance? It seems that 1ATM is not that much, but perhaps it is... That's what I'm curious about.
I'm sure at some point you need a pressurized suit to make breathing possible, but it likely has more to do with preventing decompression sickness and protecting against the cold (at very low pressure the moisture from your skin will rapidly boil, cooling off your skin).
The summary then would be that you aren't going to survive in a wheel well of an air craft above 35,000 without carrying both oxygen and a delivery system that is capable of maintaining an adequate partial pressure in your lungs.
Now when I visited NASA AMES during one of their many open houses we got to look at one of their U2 research planes and either I or one of my kids asked the pilot why they wore a 'spacesuit' and their response was "Because oxygen masks don't work above 35,000 feet." which, more accurately it would seem its harder and harder to make a working system as you go above 35,000'.
Very cool discussion btw, clearly its a very nuanced kind of thing.
Regardless (and I feel like such a broken record saying this), meaning in language is determined by consensus, not dictum, and at least for me (a 21 year old who grew up in the United States), "nauseous" can have no meaning but "sickened". "Nauseating" is what I would use for your meaning.
Humans can function to varying degrees at lower partial pressures of O2 than you experience at sea level (obviously, since people live at altitudes of up to 12K ft).
If you have not adapted to high altitude, you will experience cognitive decline at altitudes much higher than 10K ft, although they can be imperceptible. You can also go up to 30K ft, lose consciousness, but experience no long term harm as long as it's not for extended periods of time.
There have been glider pilots who have been caught in massive up drafts, climbed to 30K ft or higher, lost consciousness, then regained consciousness when they descended and safely landed their planes.
http://www.smh.com.au/news/national/dead-luck-ewas-flight-of...
It seems to be that above 40,000 feet that the oxygen you're taking in can't be absorbed if the air you're breathing isn't sufficiently pressurized. Decompression sickness will be your biggest problem.
Presumably they were talking about conventional oxygen masks and not the tight fitting, high pressure masks that pilots use.
In any case I was fairly shocked that breathing pure oxygen made such a small difference at altitude, but the difference it does make can be critical at the limits of human endurance.
just once
I approached a couple of old fellows top-roping a route on the Niagara Escarpment. I asked if they would be long, as I wanted to do the route. They invited me to jump on their rope. I had a look. It was dirty and the sheath seemed to be detaching from the core. The end was kinked and frayed. How of ten do you change your ropes, I asked in horror.
"Every time they break. Why?"
"In a lot of places around the world, the control of movement and airside control areas is not the same as what we have here."
"It's much easier in some locations to access the airside areas than it is in the UK. The only way it could be prevented is if the rest of the world tightened their procedures."
I would think the obvious solution would be to slap a big old multilingual warning sign on the wheel wells, clearly stating "flying in wheel wells WILL result in death by asphyxiation, hypothermia, and severe physical trauma".
Attempting to stop people or bombs in under carriage would EXACTLY BE SECURITY THEATER. That is an overreaction to insignificant but recently hyped/fear mongered threat that results in no statistically significant reduction in risk. But, writes up good in the papers.
People thinking like you are why security theater can exist.
However, I wasn't saying that we should be trying to stop this. I meant to show up, conversely, that a lot of the existing security is there merely for show.
How many planes have been bombed by someone sneaking something into the wheel well?
I can't imagine it would be too hard to place a bomb in the wheel well of a plane parked in Nairobi, for example. The biggest issue would be avoiding the pilot's pre-flight check.
That wouldn't be to hard to do if you are a member of a ground crew that has access to the aircraft after the pilot is on board.
BTW, we keep bombs out of the cargo area well because there was a time we didn't do this well at all. Then this happened: http://en.wikipedia.org/wiki/Air_India_Flight_182 along with this: http://en.wikipedia.org/wiki/Pan_Am_Flight_103
What might be better is having a camera or motion sensor in the wheel well that can look for surprise guests.
I almost want to go to the class graduation ceremony of every high school in america and say "tl;dr AT LEAST FUCKING GOOGLE IT." :)
We basically had to do menial tasks, like read a deck of cards, play "paddy-cake", etc., and then put our oxygen masks back on once we thought we were too impaired, while a technician was there with us.
However, I think the simulated altitude was 20k or 25k feet.
Needless to say there's a reason that O2 is (legally) required in unpressurized aircraft for anything over 10k feet.
I have flown at 12k for 1 hour and could tell that the air was much thinner and that going much higher would have started to impair.
I think that most commercial aircraft run somewhere between a 6k and 8k cabin altitude and as such a whole different set of rules apply. I don't know for sure - I'm only a private pilot.