How often do plane stowaways fall from the sky?(bbc.co.uk)
bbc.co.uk
How often do plane stowaways fall from the sky?
http://www.bbc.co.uk/news/magazine-19562101
52 comments
Even with a canister of oxygen, at 35,000 feet you can't
breath if you aren't in a pressure suit.
Partial pressures.
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...
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...
The OP said you needed a pressure suit, and that an O2 canister wouldn't help. Since the pressure of the O2 cannister will be down regulated to 1ATM, I can breath 1ATM air, no matter where I am, including 35,000 feet.
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.
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.
You can breath pressurized air directly from an air mask without wearing a pressurized suit. Many military aircraft use this system (the air mask is strapped tightly to the face to maintain pressure).
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).
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).
I found this. Towards the end, it starts talking about positive pressure respiration at high altitude.
http://webs.lanset.com/aeolusaero/Articles/A_Brief_History_o...
That's a great link. Here is another http://www.nasa.gov/centers/dryden/pdf/87912main_H-1093.pdf both of which say that if you have an air tight mask correctly valved you can breath at 40,000' on stored oxygen. (in the NASA case they were interested in getting between really high altitude and then down to 40K' in the event of a loss of cabin pressure)
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.
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.
Sea level is not the minimum oxygen levels tolerable by your body. Why, just a month or two ago I climbed to 14,000ft. Made me dizzy and nauseous , but the partial pressure was somewhere around 80mmHg.
This is true and something I should have mentioned.
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...
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...
Unless you hadn't showered for a long time prior, you were probably nauseated, not nauseous.
The OED attests that silverstorm's usage is the older one, predating yours by 8 years (1604 vs 1612).
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.
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.
Nauseous has at least two meanings, one of which is causing nausea. The other is being inclined to vomit.
Your lungs need a minimum density of air in order for the gas to pass into your blood. If you can't maintain that air density you 'outgas' only. It won't kill you immediately (you can actually survive in a complete vacuum for example) until the existing oxygen in your system runs out, then its game over.
I don't believe you can survive in a true vacuum. Your skin would bruise instantly for one.
Some anecdotal evidence here: http://www.geoffreylandis.com/vacuum.html
Even if that is true, why do you think skin bruising is lethal?
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-...
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-...
Did you read the article?
"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."
"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.
I doubt that human lungs can withstand this much difference between inside and outside pressure. I haven't found the maximum non-harmful difference but a quick google found that maximum expiratory pressure in men is 97 cmH2O. This is only about 0.08 atm.
So I wouldn't count on the canister alone, unless it is connected to a full-body suit.
So I wouldn't count on the canister alone, unless it is connected to a full-body suit.
More information on Wikipedia: http://en.wikipedia.org/wiki/Pressure_suit
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.
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.
I was watching a documentary about a group of doctors doing high altitude research while climbing Mt Everest. It was claimed in that documentary that breathing pure oxygen only increases actual oxygen intake by 5% at those sort of altitudes.
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.
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.
>How often do plane stowaways fall from the sky?
just once
just once
Reminds me of...
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?"
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?"
nyuk nyuk
But actually preventing someone slipping into the undercarriage depends on checks and procedures that are not always present, Shanks warns.
"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".
"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".
This really shows up how much of our security is theatre - if people can get into the wheel well of a flight landing at Heathrow there's very little stopping someone putting a bomb there. Yet legitimate, paying travellers have to jump through all the hoops.
I did not see statistics on # of people stopped, # of people who were deterred, and less than a 100 succeeded in hundreds of thousands of flights.
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.
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.
The statistics lacking is a very good point, and a large oversight on my part.
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.
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.
Keeping bombs out of the cargo bay is one of the things we seem to do very well, and has little to do with all the screenings we instituted since 9/11.
How many planes have been bombed by someone sneaking something into the wheel well?
How many planes have been bombed by someone sneaking something into the wheel well?
None, yet.
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
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
How many planes have been bombed full stop? As an attacker, why would you ever try to bomb a plane? Unlike a hostage-taking/hijacking where there are obvious advantages to being in a plane, if you just want to plant a bomb and kill some people you can do that much more easily in a building, or on a train, or...
This presumes people this desperate and, at the same time, willing to undertake such a fool's errand would be literate. It would also have to be a very big sign to cover even half the languages spoken in India.
What might be better is having a camera or motion sensor in the wheel well that can look for surprise guests.
What might be better is having a camera or motion sensor in the wheel well that can look for surprise guests.
I'd be interested to see graphic designers attempting to create suitable, er, designs / graphics / logos to warn of the danger.
It's probably a challenge on par with creating a warning sign for nuclear waste that will make sense 10,000 years in the future (http://www.salon.com/2002/05/10/yucca_mountain/).
I bet this would be as successful as warnings on packs of cigarettes.
Wheel-well stowaway is just about the worst thing you can do, ever. The wheel-wells are unpressurized, unheated, and designed to snugly fit the wheels in there (airplane designers don't waste space!). If you're not crushed to death upon retraction then you're almost certainly going to freeze to death or die of hypoxia. Just don't do it.
Hitching a ride on a boat full of drug-running pirates is actually safe by comparison.
There must be a way to monitor wheel well activity with cameras? And abort the flight if someone tries to get on?
Or, you know, secure the airport properly to see nothing bad or unusual is happening...
It was only 73 recorded deaths starting from 1946. This would be one of the crappiest cost/result ratio in lifesaving efforts in the history of humanity.
It should be possible, but I guess airlines probably aren't keen to spend money on something like that since they won't see it as their problem. Their paying passengers aren't the ones dying.
We all know how to deal with these parasites in the landing gear:
http://www.youtube.com/watch?feature=player_detailpage&v...
http://www.youtube.com/watch?feature=player_detailpage&v...
Anyone who googles "wheel well stowaway" finds out the risk. In one google.
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." :)
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." :)
I'm pretty sure that military pilots have to go unpressurized to 25,000 feet in order to be qualified. however they don't have to stay there for very long. and certainly not as long as the duration of a commercial flight.
When I did my training (Canadian Air Force, in the early 90's), we only had to go through controlled hypoxia training that allowed us to experience high altitude sickness, and therefore (hopefully) recognize the symptoms of it so we could react to some failure at altitude.
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.
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.
Here in the US oxygen is required for the primary crew at over 14k cabin altitude. At 12.5-14k it's required after 30 minutes. No requirement under 12.5k.
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.
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.
[deleted]
I've got "It's Raining Men" on my internal jukebox now :-(
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.