Sim so good I feinted...

[ARM505]

GGTharos is correct - it is possible that you may not notice the symptoms of hypoxia, being somewhat akin to being drunk. Feelings of euphoria, happiness or some other emotion, inability to concentrate etc. If you don't suddenly notice that you are not acting or feeling 'normal', and have the mental function to connect this to hypoxia AND are able to take corrective action (Masks on), you may well end up completely unconscious, and ultimately dead. This is NOT THE SAME as detecting that the cabin is not pressurising properly, or noticing that the cabin is climbing slowly due to other physiological effects caused by pressure change (ears popping, equalising etc)

[HemingwayFE]

GGTharos is correct - it is possible that you may not notice the symptoms of hypoxia, being somewhat akin to being drunk. Feelings of euphoria, happiness or some other emotion, inability to concentrate etc. If you don't suddenly notice that you are not acting or feeling 'normal', and have the mental function to connect this to hypoxia AND are able to take corrective action (Masks on), you may well end up completely unconscious, and ultimately dead. This is NOT THE SAME as detecting that the cabin is not pressurising properly, or noticing that the cabin is climbing slowly due to other physiological effects caused by pressure change (ears popping, equalising etc)

 

I would not buy this for a dollar. You're just mincing words or not understanding the physiological training aircrew goes through to understand/prevent this.

 

Cabin climbing to 10,000 feet triggers a Loss of Pressure horn. I ignore it and silence the horn. We climb to an altitude of 32,000 feet. I feel sleepy, and tingling in my fingers. That is going to tell me something is amiss. How do I know this? Because I've been trained to. I've detected that the cabin is not pressuring properly and/or climbing slowly causing an insidious onset of hypoxia.

 

I don't know how else to explain this.

Edited November 14, 2010 by HemingwayFE

[SimFreak]

I would not buy this for a dollar. You're just mincing words or not understanding the physiological training aircrew goes through to understand/prevent this.

 

Cabin climbing to 10,000 feet triggers a Loss of Pressure horn. I ignore it and silence the horn. We climb to an altitude of 32,000 feet. I feel sleepy, and tingling in my fingers. That is going to tell me something is amiss. How do I know this? Because I've been trained to. I've detected that the cabin is not pressuring properly and/or climbing slowly causing an insidious onset of hypoxia.

 

I don't know how else to explain this.

 

Exactly.

[Eddie]

That's all well and good, if you happen to realise that you are suffering the effects early. However this doesn't always happen, and it's been demonstated on many occasions that even experienced and trained aircrew can (and have) miss(ed) the signs and very quickly reached the point of no return, at which point they can't even follow the instructions of others telling them to put their mask on. UK military aircrew are taken to this point in training just to prove to them that if they don't act early, they are buggered.

 

At the end of the day, there have been the accidents to prove that sometimes aircrew do indeed miss the signs and symptoms.

[HemingwayFE]

That's all well and good, if you happen to realise that you are suffering the effects early. However this doesn't always happen, and it's been demonstated on many occasions that even experienced and trained aircrew can (and have) miss(ed) the signs and very quickly reached the point of no return, at which point they can't even follow the instructions of others telling them to put their mask on. UK military aircrew are taken to this point in training just to prove to them that if they don't act early, they are buggered.

 

At the end of the day, there have been the accidents to prove that sometimes aircrew do indeed miss the signs and symptoms.

 

And so are USAF aircrews. Been there, done that. I understand mishaps happen and will happen. The training is in place to prevent those mishaps. Bottom line is a crew going hypoxic is not the only reason why a plane ends up turfed. There are many other factors coming into play well before that point. Human error being chief among them.

[Bucic]

Helios Airways flt #522 crashed into a mountain for the same reason. Just imagine 140 people getting hypoxia...Terrifying

 

http://en.wikipedia.org/wiki/Helios_Airways_Flight_522

Actually it's a 'desirable way to die', however silly it may sound. Sensations far from excruciating remain until the moment very close to death, AFAIK. Not to mention the relatively safe initial phase where you go goofy and merry. However even in that phase there's a risk of 'going Ikarus'...

[159th_Viper]

Actually it's a 'desirable way to die', however silly it may sound. Sensations far from excruciating remain until the moment very close to death, AFAIK....

 

Not that simple I'm afraid :)

 

 

Differs vastly from person to person: Dealing specifically with Hypoxia as opposed to altitude sickness, decompression sickness and barotrauma, which can all affect you in an aircraft, signs are:

• Rapid Breathing
  
• Cyanosis
  
• Poor Coordination
  
• Lethargy/Lassitude
  
• Executing Poor Judgment
  

Gradual onset of Hypoxia symptoms are inter alia:

 

 

Air hunger

Severe Headache

Dizziness

Mental and Muscle Fatigue

Nausea

Hot and cold flashes

Tingling

Visual Impairment

Euphoria

 

As opposed to rapid onset, symptoms whereof are:

 

Cyanosis (Blue discoloration of the skin)

Shortness of breath

Seizures

Coma

Priapism

Death, in some cases.

 

Not fun and definitely not desirable.

Edited November 14, 2010 by 159th_Viper
Grammar

[HemingwayFE]

Actually it's a 'desirable way to die', however silly it may sound. Sensations far from excruciating remain until the moment very close to death, AFAIK. Not to mention the relatively safe initial phase where you go goofy and merry. However even in that phase there's a risk of 'going Ikarus'...

 

There's no damn desirable way to die in an airplane.

[Bucic]

Not that simple I'm afraid :)

I simplified but I didn't say it was simple ;)

[159th_Viper]

I simplified but I didn't say it was simple ;)

 

Granted.

 

Merely an attempt to correct a common misconception that Hypoxia leads to a 'relatively safe initial phase where you go goofy and merry' - That would be referring to Narcosis, specifically Nitrogen Narcosis ;)

[Eddie]

Bottom line is a crew going hypoxic is not the only reason why a plane ends up turfed. There are many other factors coming into play well before that point. Human error being chief among them.

 

Totally agree, but it can be a major contributing factor. Your original post gave the impression that you can always spot the signs and act accordingly, I'd merely like to state that this isn't always the case for vairous reasons. As we all know, there is always someone one thinks they know better than what they were told in training.

 

Find me an aircraft accident or near miss where human error wasn't involved at some point. ;) (ok there are one or two, but not many)

[Bucic]

Granted.

 

Merely an attempt to correct a common misconception that Hypoxia leads to a 'relatively safe initial phase where you go goofy and merry' - That would be referring to Narcosis, specifically Nitrogen Narcosis ;)

If 5000 - 6000 m MSL counts for 'initial phase of hypoxia' then I know exactly what I am talking about and no one fed me Nitrogen ;) The only misunderstanding here may be vocabulary.

[HemingwayFE]

Totally agree, but it can be a major contributing factor. Your original post gave the impression that you can always spot the signs and act accordingly, I'd merely like to state that this isn't always the case for vairous reasons. As we all know, there is always someone one thinks they know better than what they were told in training.

 

Find me an aircraft accident or near miss where human error wasn't involved at some point. ;) (ok there are one or two, but not many)

 

I was speaking to the point that training provides the means and tools to deal with most any situation. Ad yea, you should be able figure out what the hell is going on. Doesn't mean it always happens, but if you're with the aircraft then I don't see why you shouldn't.

 

EDIT: I should also add that it would hopefully never get that far anyway. Taking a glance at the pressurization panel needs all of a second or so.

 

The Helios crew punched their tickets well before wheels up.

Edited November 14, 2010 by HemingwayFE

[Beagle One]

This happens to me when I was 13 on a trip in a single engine Piper from Germany to Jugoslavia. Somewhere over the alps at 12.000 feet I got very, very tired...it turned out later my oxigen mask did not work.

 

The altitude was mandatory due to clouds and only VFR equipment.

[rud]

I think most of us can agree that oxygen is important and it's a good idea to have a bunch of it handy when one is flying a plane.

 

I'm just glad the environmental system has such a pronounced effect. I hope that Black Shark gets patched up to include this and we see a rush of Ka-50 pilots taking off their weapons, taking on only 10% fuel, and shooting up into the sky to try and see it for themselves.

[ARM505]

All I'm saying is that hypoxia is notoriously difficult to self-diagnose. Your brain is the first organ to be affected, before your eyes and ears. It's very, very easy to sit on the ground and say 'hmmm, if I noticed that I was blue in my fingertips, feeling slightly dreamy/etc I'm sure I'd do something proactive'. Your thought process is impaired - you have to 'snap out of it' and do something, which doesn't always happen. This alone has killed people - that is an unalterable fact, so it is clearly a threat by itself. Also, everyone seems to think that aircrew all have to undergo a flip in a high alt chamber - that simply isn't true. Military maybe, civilian, no (or at least not under the regs I fly, heavily JAR (or whatever it is nowdays!) influenced). I fly 737's every day, and I have never experienced hypoxia, intentional or not.

 

In summary - you cannot plan to RELIABLY self diagnose it, unlike in DCS where the symptoms are obvious and the remedy very very clear. That is my 2c, backed up by real world theory, training, and the fact that hypoxia is a proven killer, despite crew KNOWING about it and having access to oxygen.

[Druid_]

Well said ARM505

 

I'd like to see how the 'can't be that difficult' posters operate after 3 back to back 12 hour night duties, or a 20 hour ULR (Ultra Long Range) flight.

 

Even Approach and landing the aircraft becomes a much more difficult task under these circumstances and I challenge any sleep deprived person to have the spare mental capacity to realise that he/she is suffering from the symptoms of hypoxia. In the end its the aircrafts warning systems that will save you.

 

In fact I'd go as far to say that your average overworked airline pilot might spend some of his rostered month feeling in a constant state of hypoxia.:cry:

 

An accident is usually a result of more than 1 factor. It is rarely so cut and dry.

 

Anyway, my 2c.

 

For those who want to know what happened to Helios 522 then click here.

and ... spare a thought for the golfer Payne Stewart, his flight lasted less than 14 mins as far as he was concerned! link

[PourLeMerite]

I take it HeminhgwayFe and Simfreak your are an actual pilots who has done this kind of stuff for real yes. Was this in military aircraft of civilian? if it makes any difference.

 

Me...well this sim is the closest I have ever got to even being in a plane, never been in one at all, so count yourselves lucky to have experienced the real thing and thanks for all the tips and real accounts interesting stuff.

 

Still no sure what the air bleed thing is in the A10, should I put it on during flight check or what, and what does it do?

[NoJoe]

All I'm saying is that hypoxia is notoriously difficult to self-diagnose.

 

That's true: notoriously difficult to diagnose. But not impossible.

 

I got to do an altitude chamber trip down to Peterson AFB in Colorado Springs a couple years ago and experience a pressure altitude of 25,000 MSL. It was essentially a pretty fast decompression. We were given little sheets to work on that had things like simple math problems, word puzzles, and the like.

 

Most of us were able to recognize our personal symptoms and then put the oxygen mask back on. I lasted around 4 minutes before I realized I couldn't subtract 5 from 7 and figured I'd better put that mask on and turn on the O2! (interestingly, we were using the exact same panel that's in the A-10) :D

 

There were several people, though, who got to the point of no return (past the "Time of Useful Consciousness") before they could recognize and react to the hypoxia. One of them (our teacher, nonetheless! ) was unable to even follow the direct instructions to put his mask on, and had to be helped. That was pretty interesting!

 

So yes, while it is difficult to recognize the symptoms (especially if you're not expecting it, and history backs that up with multiple crashes), it's not impossible, and probably not as hard as most would expect. It certainly helps that I now know my own personal symptoms, and can recognize them early.

 

And for what it's worth I'm a civilian flight instructor, flying mostly single engine non-pressurized Cessnas and the like.

 

--NoJoe

Edited November 15, 2010 by NoJoe
typo

[lubey]

I think a system should be invented to help an aircrew who is suffering hypoxia and can't be raised on the radios so something can be done during these incidents in the future.

 

Maybe some sort of UAV deployed from a B-52 that clamps itself to the aircraft fueselage and then has a massive air scoop which repressurises the cabin via the ram effect. Or maybe the UAV could have large enough wings and control surfaces that once clamped on it or a human operator could fly the doomed plane down to a safe altitute.

[Napa]

and ... spare a thought for the golfer Payne Stewart, his flight lasted less than 14 mins as far as he was concerned! link

 

Spare a thought for all those people in Helios flight too who died in their sleep. Lets hope something like that never happens again. As I said in my previous post, I knew a guy in that flight (only met a couple of times though) and a friend of a friend lost BOTH his parents in that flight at the age of 24. RIP...

 

Anyway, for those who want to know the latest: The case is still in criminal-court with 7 new testimonies, 5 from Boeing and 2 from National Transportation Safety Board with the method of TV-video live link. The Criminal Court ruled that it has no power to order testimony by video-conferencing, noting that the matter should be brought before the Legislature.

 

It is the first time in the history of Cyprus Justice submitted a request to take testimony via remote videoconferencing in criminal proceedings.

[Druid_]

Spare a thought for all those people in Helios flight too who died in their sleep. Lets hope something like that never happens again.

Absolutely. Any aircraft accident is a tradegy.

 

There was also a Doctor onboard the Helios flight who will have known the symptoms of hypoxia. Its one thing to sit in a chamber knowing whats about to happen and another to realise whats happening for real on a 'routine' flight.

[Thurston]

Honestly, it is pretty cool that its modeled in this sim.

 

We had to go to training about every two years regarding this very issue. We would go to the altitude chamber and be exposed to high altitudes. The idea was we could learn to identify our Hypoxia symptoms. Believe me you can tell. The problem is those symptoms can change ever so often and that is why we had to keep going back for more chamber rides. The most dangerous symptom was euphoria. If you had that particular symptom.....you tend to just enjoy the whole experience and are much more likely to not do anything about it. It was always fun to see other crewdogs gimp out with Hypoxia. Those where the good ole days....been out of the service for about 10 years now but I remember that training well.

[HemingwayFE]

In summary - you cannot plan to RELIABLY self diagnose it, unlike in DCS where the symptoms are obvious and the remedy very very clear. That is my 2c, backed up by real world theory, training, and the fact that hypoxia is a proven killer, despite crew KNOWING about it and having access to oxygen.

 

I never said it was easy to recognize. The training is there to provide a toolset. It's not a 100% guarantee. And yes, all USAF flyers undergo altitude chamber training.

 

Well said ARM505

 

I'd like to see how the 'can't be that difficult' posters operate after 3 back to back 12 hour night duties, or a 20 hour ULR (Ultra Long Range) flight.

 

Even Approach and landing the aircraft becomes a much more difficult task under these circumstances and I challenge any sleep deprived person to have the spare mental capacity to realise that he/she is suffering from the symptoms of hypoxia. In the end its the aircrafts warning systems that will save you.

 

In fact I'd go as far to say that your average overworked airline pilot might spend some of his rostered month feeling in a constant state of hypoxia.:cry:

 

An accident is usually a result of more than 1 factor. It is rarely so cut and dry.

 

Anyway, my 2c.

 

12 hour night duties would be great. I routinely pull 12+ on flying days. I know the rigors of back to back flying. That's why we do an Operational Risk Management sheet. The Aircraft Commander has, at a glance, a good snapshot of the crew's ability. Am I still sharp on the 3rd 14 hour sortie of the week? Yup. Am I still fallible to mistakes? Yup. No denying that. If I'm following the checklists and so are the other guys there shouldn't (note how I didn't say never) be an issue catching something early. And for the record, I never said anything near 'can't be that difficult'. I'm not that big of a dumb dumb.

 

 

I take it HeminhgwayFe and Simfreak your are an actual pilots who has done this kind of stuff for real yes. Was this in military aircraft of civilian? if it makes any difference.

 

Me...well this sim is the closest I have ever got to even being in a plane, never been in one at all, so count yourselves lucky to have experienced the real thing and thanks for all the tips and real accounts interesting stuff.

 

Still no sure what the air bleed thing is in the A10, should I put it on during flight check or what, and what does it do?

 

I'm an E-3 Sentry flight engineer. Bleed air is air tapped off from either a ground cart, auxiliary power unit, or the aircraft's engine. You need bleed air on to use things like the A/C system which, in turn, pressurizes the aircraft.

 

Bleed air from an APU or ground cart is used to start the aircraft's engine--2 things needed, one being electrical power and the other being air. Air engages the starter turbine which then cranks the engine turbine (most likely an N2 turbine shaft then followed by an N1 turbine--that's how it is on the TF-33 anyhow).

[SimFreak]

I take it HeminhgwayFe and Simfreak your are an actual pilots who has done this kind of stuff for real yes. Was this in military aircraft of civilian? if it makes any difference.

 

Me...well this sim is the closest I have ever got to even being in a plane, never been in one at all, so count yourselves lucky to have experienced the real thing and thanks for all the tips and real accounts interesting stuff.

 

Still no sure what the air bleed thing is in the A10, should I put it on during flight check or what, and what does it do?

 

I have my wings with radiator. Lets just keep it at that.