Can pilots REALLY concentrate at 35,000 feet?
There's an aricle in Flight International this week about "Hypoxia like" incidents when flying the F-22 Raptor. Now, there is simply no way that anything that happens to an F-22 pilot could be likened to a civilian air transport pilot but I found one paragraph interesting in relation to this discussion.
USAF pinpoints root cause of F-22 Raptor is the whole article. The paragraph that I find interesting is towards the end:
In the early days of jet aviation, Schwartz says, the aerospace physiology community played a very large role. But in recent years, that base of expertise has atrophied. "The engineering know how that's associated with that has diminished, I think, even on a national basis."Now, again, I am not trying to make a direct correlation here that would be silly. But I find it intresting the there seems to have been no real research into the effects of working at altitude (unless someone knows different.....)
USAF pinpoints root cause of F-22 Raptor is the whole article. The paragraph that I find interesting is towards the end:
In the early days of jet aviation, Schwartz says, the aerospace physiology community played a very large role. But in recent years, that base of expertise has atrophied. "The engineering know how that's associated with that has diminished, I think, even on a national basis."
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If it can happen to climbers, why would pilots be immune?
Well - of course I'm not a doctor. ...And indeed I'm not much of a pilot either. But I did once manage to get a Victa Airtourer to climb to over 9000 feet - at which - point both plane and pilor were struggling.
But really, what we're doing to passengers (and pilots) in airliners, is asking them to ascend from not much above sea level to 8000 feet very quickly.
There's really not much difference between people in a plane and people climbing mountains. ....And we know altitude sickness can begin to affect otherwise healthy people at just 5000 feet after just a few hours ( maybe over three or four) at that level.
Acute Mountain Sickness (AMS) apparently starts to manifest itself at anything above 6,500 ft.. Symptoms include headache, fatigue, stomach illness, dizziness.
..........So, if it can happen to fit people like climbers - what's so special about pilots - or, come to that, passengers?
Frankly I have to confess I don't feel all that great after a long flight - like one of those bone-crackers from Los Angeles to London.. And I guess that goes for a fair proportion of the other passengers.......... But we knew what we were getting into when we booked - and if our performance is poorer than normal it probably won't matter.that much ...As for the pilots though - Well that's a different matter..
Air France 447 had been in the air for around 4 hours when the pilots (at cabin pressurre of 8000 feet) were overwhelmed by the emergency and clearly weren't able to think straight. The Captain had been off-watch asleep - but how many pilots - let alone passengers - when roused from a relatively low-oxygen slumber at 8000 feet would be sharp enough to deal logically with a multi faceted emergency like that?
But really, what we're doing to passengers (and pilots) in airliners, is asking them to ascend from not much above sea level to 8000 feet very quickly.
There's really not much difference between people in a plane and people climbing mountains. ....And we know altitude sickness can begin to affect otherwise healthy people at just 5000 feet after just a few hours ( maybe over three or four) at that level.
Acute Mountain Sickness (AMS) apparently starts to manifest itself at anything above 6,500 ft.. Symptoms include headache, fatigue, stomach illness, dizziness.
..........So, if it can happen to fit people like climbers - what's so special about pilots - or, come to that, passengers?
Frankly I have to confess I don't feel all that great after a long flight - like one of those bone-crackers from Los Angeles to London.. And I guess that goes for a fair proportion of the other passengers.......... But we knew what we were getting into when we booked - and if our performance is poorer than normal it probably won't matter.that much ...As for the pilots though - Well that's a different matter..
Air France 447 had been in the air for around 4 hours when the pilots (at cabin pressurre of 8000 feet) were overwhelmed by the emergency and clearly weren't able to think straight. The Captain had been off-watch asleep - but how many pilots - let alone passengers - when roused from a relatively low-oxygen slumber at 8000 feet would be sharp enough to deal logically with a multi faceted emergency like that?
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No, they have great difficulty performing the simplest tasks - and that's when they are awake. I'm constantly having to enter the flight deck on my portable oxygen bottle and either wake them up or help them fly the aircraft. If you ask me, this is an accident waiting to happen...
Hartington,
There certainly have been studies although I can't point to an example of one online at the moment. I know there have been because I have read one or two and have actually been a guinea pig for another couple over the years!
I often work at 14,000 feet (on Mauna Kea, unpressurised) and I don't know anyone working at that altitude that doesn't suffer at least one sympton of high altitude sickness, although it's usually very minor (e.g., slight headache). I can count the number of people whose mental performance is not degraded in some way on the fingers of one hand (there's one remarkable individual I know whose mental performance actually seems to improve at altitude!).
As someone mentioned, it's the partial pressure of oxygen that's the important thing, not the actual percentage of oxygen in the atmosphere (which is essentially unchanged at these altitudes). What I can tell you is that most if not all altitude related problems seem to go away when we stay at the accommodation at 9,000 feet (again unpressurised). Although most people find it hard to sleep at that altitude, at least initially, mental performance is rarely degraded.
Given my own experience I don't think working at an altitude of 8,000 feet is much of an issue for most especially if it's not particularly physical work, but you don't need to go much higher to start having problems, especially if you are not acclimated.
Now, again, I am not trying to make a direct correlation here that would be silly. But I find it intresting the there seems to have been no real research into the effects of working at altitude (unless someone knows different.....)
I often work at 14,000 feet (on Mauna Kea, unpressurised) and I don't know anyone working at that altitude that doesn't suffer at least one sympton of high altitude sickness, although it's usually very minor (e.g., slight headache). I can count the number of people whose mental performance is not degraded in some way on the fingers of one hand (there's one remarkable individual I know whose mental performance actually seems to improve at altitude!).
As someone mentioned, it's the partial pressure of oxygen that's the important thing, not the actual percentage of oxygen in the atmosphere (which is essentially unchanged at these altitudes). What I can tell you is that most if not all altitude related problems seem to go away when we stay at the accommodation at 9,000 feet (again unpressurised). Although most people find it hard to sleep at that altitude, at least initially, mental performance is rarely degraded.
Given my own experience I don't think working at an altitude of 8,000 feet is much of an issue for most especially if it's not particularly physical work, but you don't need to go much higher to start having problems, especially if you are not acclimated.
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If the pax had abnormal air, it would make the work of the CC easier! They could sit with their O2 masks on and giggle as we sat goggle eyed, unable to reach the call button!
Recollections from military training! At 10000', the partial pressure of O2 is 1/2 that at sea level which is the point at which you start needing to increase the level of O2, so a military mask will start to give an O2 airmix to solve this problem. More clever stuff happens higher up.
It is ok to operate at this 10000 level indefinitely but above that not so, which is why the CABIN ALT warning goes off at 10000' cabin alt.
Problems with concentration come not from the reduced O2 in a properly functioning cockpit but from a myriad of factors - time zone changes, sleep patterns, diet, temperature, vibration, noise, under arousal among others and some or all of which exist in aviation and other careers. Certainly in a short-term office based job poor eating habits, insufficient sleep, repetitive work, higher temperatures and others made concentration very difficult.
It is ok to operate at this 10000 level indefinitely but above that not so, which is why the CABIN ALT warning goes off at 10000' cabin alt.
Problems with concentration come not from the reduced O2 in a properly functioning cockpit but from a myriad of factors - time zone changes, sleep patterns, diet, temperature, vibration, noise, under arousal among others and some or all of which exist in aviation and other careers. Certainly in a short-term office based job poor eating habits, insufficient sleep, repetitive work, higher temperatures and others made concentration very difficult.
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The real reason pilots are nodding off on the flight deck.
I hadn't planned to add any more to this thread - but the interesting comments made here prompted me to do a little more research.
The more I looked the more obvious it became - the scientists, the airlines, the CAA, BALPA and Parliament are all missing the point.
They've all tried to explain why pilots fall asleep on the flight deck, or why their performance -when awake - is so degraded it results in increased risk to the flight or even an accident. ....And they all blame pilot rosters, insufficient sleep, insufficient breaks and "flying around the backside of the clock".
However incontrovertible peer-reviewed studies like that by J H Goode (Journal of Safety Research "Are pilots at risk of accidents due to fatigue?" Issue 34: Pages 309–313) produce graphs show that the longer the flight, the greater the likelihood of accident - and again lack of sleep gets the blame:-.
Loads of work has been done on the circadian rhythms (i.e. sleep/wake patterns) of flight crew. Books like "Lag: A Look at Circadian Rhythms" by Bill Ragan highlights the tactic of taking a "power nap" on the flight deck (one pilot at a time of course) - but we all know what happens then. A sleepy Air Canada pilot suddenly wakes up, totally disorientated, spots a bright light (the planet Venus), thinks it's an oncoming plane and cranks his aircraft into a nosedive. It would be funny if it wasn't for the fact that 16 passengers were injured and he nearly hit a real aircraft flying below him.
Mr Ragan says its not only airline pilots who "power nap" - so do military pilots - 94% of them. He also says military pilots also use drugs like dextroamphetamine to stay alert on 54% of missions.
BUT .... it doesn't seem to have occured to any of these researchers is that very probably the real reason airline and military pilots are nodding off is not so much because of lack of sleep and roster patterns. The real culprit is that recycled, rarified air - air which just has too few oxygen molecules in it. The longer pilots work at an equivalent atmospheric pressure of 8000 feet (or even higher) the worse they perform.
Astonishingly the CAA's 2007 weighty paper entitled “Aircrew Fatigue" -a learned treatise some 68 pages long - doesn't even mention cabin air pressure or oxygen levels once. Maybe they should take another look at this
What's the answer? Well clearly the ironically-named Boeing Dreamliner is, paradoxically, the one airliner which is the least likely to send you to sleep because it has a cabin pressure equivalent to 6000 feet. As for the rest of the world's airliners - they'd probably start rupturing their skins if the internal pressure was pumped up.
.....So I suppose we'll have to leave things the way they are until they all get scrapped - maybe 25 even 50 years from now....keep our fingers crossed...hope for the best .....and nod off.....
The more I looked the more obvious it became - the scientists, the airlines, the CAA, BALPA and Parliament are all missing the point.
They've all tried to explain why pilots fall asleep on the flight deck, or why their performance -when awake - is so degraded it results in increased risk to the flight or even an accident. ....And they all blame pilot rosters, insufficient sleep, insufficient breaks and "flying around the backside of the clock".
However incontrovertible peer-reviewed studies like that by J H Goode (Journal of Safety Research "Are pilots at risk of accidents due to fatigue?" Issue 34: Pages 309–313) produce graphs show that the longer the flight, the greater the likelihood of accident - and again lack of sleep gets the blame:-.
- Fly for 1 - 6 hours and you have fewer accidents than the average for all pilots.
- Fly for 7 - 9 hours and you have slightly above average risk of accident (1.1 times the average)
- Fly 10 - 12 hours and the risk rises to 1.7 times that of all pilots
- Fly over 13 hours and the proportion is 5.62 times higher.....and that is a lot
Loads of work has been done on the circadian rhythms (i.e. sleep/wake patterns) of flight crew. Books like "Lag: A Look at Circadian Rhythms" by Bill Ragan highlights the tactic of taking a "power nap" on the flight deck (one pilot at a time of course) - but we all know what happens then. A sleepy Air Canada pilot suddenly wakes up, totally disorientated, spots a bright light (the planet Venus), thinks it's an oncoming plane and cranks his aircraft into a nosedive. It would be funny if it wasn't for the fact that 16 passengers were injured and he nearly hit a real aircraft flying below him.
Mr Ragan says its not only airline pilots who "power nap" - so do military pilots - 94% of them. He also says military pilots also use drugs like dextroamphetamine to stay alert on 54% of missions.
BUT .... it doesn't seem to have occured to any of these researchers is that very probably the real reason airline and military pilots are nodding off is not so much because of lack of sleep and roster patterns. The real culprit is that recycled, rarified air - air which just has too few oxygen molecules in it. The longer pilots work at an equivalent atmospheric pressure of 8000 feet (or even higher) the worse they perform.
Astonishingly the CAA's 2007 weighty paper entitled “Aircrew Fatigue" -a learned treatise some 68 pages long - doesn't even mention cabin air pressure or oxygen levels once. Maybe they should take another look at this
What's the answer? Well clearly the ironically-named Boeing Dreamliner is, paradoxically, the one airliner which is the least likely to send you to sleep because it has a cabin pressure equivalent to 6000 feet. As for the rest of the world's airliners - they'd probably start rupturing their skins if the internal pressure was pumped up.
.....So I suppose we'll have to leave things the way they are until they all get scrapped - maybe 25 even 50 years from now....keep our fingers crossed...hope for the best .....and nod off.....
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Am really glad this issue has been raised, and good on you Korrol for sticking with it in the face of some less than encouraging posts.
I'm not a Doctor, but it's NOT NORMAL to spend your working day at 8000' breathing in stale farts and skin flakes. It must have an effect, what that is needs some proper analysis.
We, as a workforce are our own worst enemy in these and other issues, by that I mean we don't tend to 'make a fuss'. For example, when your mate down the pub asks you how your day was (eg ugly scenes at INN, SMI, JMK etc) the typical response is "fine".
There is an issue here, it should be investigated and the results made clear, not least to airline management, who think we sit in a comfy chair watching 'the computers' do the work!!
I'm not a Doctor, but it's NOT NORMAL to spend your working day at 8000' breathing in stale farts and skin flakes. It must have an effect, what that is needs some proper analysis.
We, as a workforce are our own worst enemy in these and other issues, by that I mean we don't tend to 'make a fuss'. For example, when your mate down the pub asks you how your day was (eg ugly scenes at INN, SMI, JMK etc) the typical response is "fine".
There is an issue here, it should be investigated and the results made clear, not least to airline management, who think we sit in a comfy chair watching 'the computers' do the work!!
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Hi,
Just wanted to make sure that you understand the difference between PERCENTAGE of something and the AMOUNT of something....
Anyway, I had a little browse and found this which you might find interesting (or take with a pinch of salt etc...)
Just wanted to make sure that you understand the difference between PERCENTAGE of something and the AMOUNT of something....
Anyway, I had a little browse and found this which you might find interesting (or take with a pinch of salt etc...)
crippen
No, they don't.
The reason, I would guess: great additional cost for little increase in realism.
Most, but not all, simulator work is carried out close to airport level.
If simulating high level cruise or a high level airport at, say, 8000ft, the alteration in aircraft handling characteristics will be reproduced but not the physiological effect of the reduction in pp of O2.
Do the flight simulators have reduced pressure in them?
The reason, I would guess: great additional cost for little increase in realism.
Most, but not all, simulator work is carried out close to airport level.
If simulating high level cruise or a high level airport at, say, 8000ft, the alteration in aircraft handling characteristics will be reproduced but not the physiological effect of the reduction in pp of O2.
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There is some good info in this thread and some mis-information.
As has been stated, the percentage of oxygen in the air is the same at all levels (in and outside the cabin) but the partial pressure will reduce at altitude. At 10,000 ft the pressure is about 85% of sea level pressure and at 18,000 ft it is about half.
Cabin altitude in cruise is typically 6-7000 ft and never above 8000 ft unless something has gone wrong.
Your body - and the pilot's - won't have any significant drop in blood oxygen levels in spite of the reduced pressure, because the body's need for oxygen is quite low as we are mainly sitting. There is not any significant or measureable effect on mental performance.
This is also why altitude sickness is not a concern at these levels. Smokers handicap themselves with equivalent of a few thousand feet extra altitude, but that has never shown significant negative effects on mental performance at these altitudes.
Even at 14,000 ft most people are "fully functional", although they may be losing some mental performance. Back in the early days of aviation pilots regularly flew at these altitudes without oxygen.
For a healthy person on an airplane, your brain can get all the oxygen it needs during a normal flight.
The effects of fatigue are much more significant on pilot performance. The airline business with its industrial attitude to crew duty times and rest requirements is a thousand times more significant in putting a "slow" pilot in the seat.
As has been stated, the percentage of oxygen in the air is the same at all levels (in and outside the cabin) but the partial pressure will reduce at altitude. At 10,000 ft the pressure is about 85% of sea level pressure and at 18,000 ft it is about half.
Cabin altitude in cruise is typically 6-7000 ft and never above 8000 ft unless something has gone wrong.
Your body - and the pilot's - won't have any significant drop in blood oxygen levels in spite of the reduced pressure, because the body's need for oxygen is quite low as we are mainly sitting. There is not any significant or measureable effect on mental performance.
This is also why altitude sickness is not a concern at these levels. Smokers handicap themselves with equivalent of a few thousand feet extra altitude, but that has never shown significant negative effects on mental performance at these altitudes.
Even at 14,000 ft most people are "fully functional", although they may be losing some mental performance. Back in the early days of aviation pilots regularly flew at these altitudes without oxygen.
For a healthy person on an airplane, your brain can get all the oxygen it needs during a normal flight.
The effects of fatigue are much more significant on pilot performance. The airline business with its industrial attitude to crew duty times and rest requirements is a thousand times more significant in putting a "slow" pilot in the seat.
Last edited by AtoBsafely; 4th Aug 2012 at 02:36.
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Why the CAA should test pilots - and passengers - at altitude
Instinctively I'm so not sure that AtoB is right about his assertion that most airliners are usually being pressurised to 6500 feet. I would bet that they're not - but would be more than happy to look at any evidence that this is the case.
Apart from the Dreamliner - which we've already mentioned here - it must cost more to crank up the pressure above the "accepted" 8000 level - not just in power but in ensuring the aircraft will remain robust enough, over its long service life, to withstand the repeated pressurisation cycles to contain a 6500 ft pressure at - say 35,000 feet. We all know about the incidents in which the skins of high-cycle aircraft have failed . 8000 ft pressure was enough to peel back the roof of that Aloha airlines 737 in 1988. ......Just imagine what the pressure equivalent of 6500 feet would have done.
Another factor in crew (and passenger) alertness - or lack of it after, say, 4 hours at 35,000 feet (pressurised to the equivalent of 8000feet) is something that hasn't been discussed here so far - the temperature of the air. When cold rarified air is drawn in at 35,000 feet AND heated to 70 degrees F (to say nothing of its subsequently being recycled) it must further reduce the concentration of oxygen molecules. Ergo - there may well be less oxygen available in this heated rarified air than people might think.
In summary I think we need some hard evidence to prove the often-made but totally unproven assertion that the performance of pilots and passengers is NOT degraded after sustained (3 hours or more) flight at 35,000 feet.
The way to establish what's really going on here is for the CAA to carry out cognitive ability tests of pilots (and passengers) . Test them on the ground at sea level - and then see how they perform after flying for at least three hours at 35,000 feet in an aircraft pressurised to 8000 feet. It would be a safe bet that performance would be worse at 35,000 feet.
........Such tests would settle the issue once and for all - and may well result in far reaching changes and safer flying.
Apart from the Dreamliner - which we've already mentioned here - it must cost more to crank up the pressure above the "accepted" 8000 level - not just in power but in ensuring the aircraft will remain robust enough, over its long service life, to withstand the repeated pressurisation cycles to contain a 6500 ft pressure at - say 35,000 feet. We all know about the incidents in which the skins of high-cycle aircraft have failed . 8000 ft pressure was enough to peel back the roof of that Aloha airlines 737 in 1988. ......Just imagine what the pressure equivalent of 6500 feet would have done.
Another factor in crew (and passenger) alertness - or lack of it after, say, 4 hours at 35,000 feet (pressurised to the equivalent of 8000feet) is something that hasn't been discussed here so far - the temperature of the air. When cold rarified air is drawn in at 35,000 feet AND heated to 70 degrees F (to say nothing of its subsequently being recycled) it must further reduce the concentration of oxygen molecules. Ergo - there may well be less oxygen available in this heated rarified air than people might think.
In summary I think we need some hard evidence to prove the often-made but totally unproven assertion that the performance of pilots and passengers is NOT degraded after sustained (3 hours or more) flight at 35,000 feet.
The way to establish what's really going on here is for the CAA to carry out cognitive ability tests of pilots (and passengers) . Test them on the ground at sea level - and then see how they perform after flying for at least three hours at 35,000 feet in an aircraft pressurised to 8000 feet. It would be a safe bet that performance would be worse at 35,000 feet.
........Such tests would settle the issue once and for all - and may well result in far reaching changes and safer flying.
Last edited by korrol; 9th Aug 2012 at 06:12.
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........Such tests would settle the issue once and for all - and may well result in far reaching changes and safer flying.
...I'm so not sure that AtoB is right about his assertion that most airliners are usually being pressurised to 6500 feet. I would bet that they're not - but would be more than happy to look at any evidence that this is the case.
8000 ft pressure was enough to peel back the roof of that Aloha airlines 737 in 1988. ......Just imagine what the pressure equivalent of 6500 feet would have done.
...I think we need some hard evidence to prove the often-made but totally unproven assertion that the performance of pilots and passengers is NOT degraded
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Korrol,
As you obviously have no need for facts and summarily dismisses them and weighs "instinct" or what you "think" much higher, here's a few other things for you to ignore.
You require evidence to disprove your "instinct". How about you prove your "instinct".
As it happens AtoB is entirely correct. Also note that AtoB did not say "pressurised to..." as aircraft are not pressurised to an altitude, despite your "as we all know" claim. Aircraft are pressurised to a maintain a constant differential pressure, not a specific altitude. The resulting cabin altitude is a function of ambient pressure. Knowing that the differential pressure is between 8 and 9 PSI, depending on aircraft type, it is not difficult to calculate the resulting cabin altitude.
You appear somewhat confused here. "crank up the pressure to above...8000". It is again apparent that you do not understand how an aircraft pressurisation system works. The Aloha flight was a short one, so it was cruising at FL240. You do the math, it is not difficult.
Complete nonsense, is the kindest thing that can be said.
Not really. What we need is you providing some hard evidence to prove your often-made but totally unproven assertion that the performance of pilots and passengers is degraded after sustained (3 hours or more) flight at 35,000 feet.
Knowledgeable people already know what's going on. They have known for some time. The effects of altitude on physical and cognitive abilities have been examined numerous times by both military and civilian organisations.
The only issue is your idče fixe.
As you obviously have no need for facts and summarily dismisses them and weighs "instinct" or what you "think" much higher, here's a few other things for you to ignore.
Instinctively I'm so not sure that AtoB is right about his assertion that most airliners are usually being pressurised to 6500 feet. I would bet that they're not - but would be more than happy to look at any evidence that this is the case.
As it happens AtoB is entirely correct. Also note that AtoB did not say "pressurised to..." as aircraft are not pressurised to an altitude, despite your "as we all know" claim. Aircraft are pressurised to a maintain a constant differential pressure, not a specific altitude. The resulting cabin altitude is a function of ambient pressure. Knowing that the differential pressure is between 8 and 9 PSI, depending on aircraft type, it is not difficult to calculate the resulting cabin altitude.
Apart from the Dreamliner - which we've already mentioned here - it must cost more to crank up the pressure above the "accepted" 8000 level - not just in power but in ensuring the aircraft will remain robust enough, over its long service life, to withstand the repeated pressurisation cycles to contain a 6500 ft pressure at - say 35,000 feet. We all know about the incidents in which the skins of high-cycle aircraft have failed . 8000 ft pressure was enough to peel back the roof of that Aloha airlines 737 in 1988. ......Just imagine what the pressure equivalent of 6500 feet would have done.
Another factor in crew (and passenger) alertness - or lack of it after, say, 4 hours at 35,000 feet (pressurised to the equivalent of 8000feet) is something that hasn't been discussed here so far - the temperature of the air. When cold rarified air is drawn in at 35,000 feet AND heated to 70 degrees F (to say nothing of its subsequently being recycled) it must further reduce the concentration of oxygen molecules. Ergo - there may well be less oxygen available in this heated rarified air than people might think.
In summary I think we need some hard evidence to prove the often-made but totally unproven assertion that the performance of pilots and passengers is NOT degraded after sustained (3 hours or more) flight at 35,000 feet.
The way to establish what's really going on here is for the CAA to carry out cognitive ability tests of pilots (and passengers) . Test them on the ground at sea level - and then see how they perform after flying for at least three hours at 35,000 feet in an aircraft pressurised to 8000 feet. It would be a safe bet that performance would be worse at 35,000 feet.
........Such tests would settle the issue once and for all
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Korrol
Why the Pax??
If such a test were done (and I really don't care one way or the other) pax could not be a 'control group' for flight and cabin crew.
(yawn) The air pressure today is really high and it's made me very tired, so I'm off to have a snooze.
The way to establish what's really going on here is for the CAA to carry out cognitive ability tests of pilots (and passengers)
- Pax are not working.
- Pax may have BEEN working and be tired.
- Pax may have delayed meals to hurry to the airport and have low blood sugars at the start and be less alert.
- Etc.
If such a test were done (and I really don't care one way or the other) pax could not be a 'control group' for flight and cabin crew.
(yawn) The air pressure today is really high and it's made me very tired, so I'm off to have a snooze.
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Well, as somebody who has been around long enough to remember travelling from the channel ports across europ in 2nd class sitty up trains, and who still occasionally does an overnight drive to the alps with friends, I can confirm that performance is degraded much more significantly during such ground level experiences, rather than a Europe-west coast americas hop at 35000 feet.
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Korrol,
The lack of oxygen is not an issue at the slightly reduced pressures of an aircraft cabin.
People inside an aircraft tend to feel drowsy because:
- they are not moving about much (check out "stagnant hypoxia"),
- they don't have much to do, and
- the constant noise is actually quite fatiguing, and tends to put you to sleep.
The lack of oxygen is not an issue at the slightly reduced pressures of an aircraft cabin.
People inside an aircraft tend to feel drowsy because:
- they are not moving about much (check out "stagnant hypoxia"),
- they don't have much to do, and
- the constant noise is actually quite fatiguing, and tends to put you to sleep.