Asphyxia Modeled?

[[TWB]Sauerkraut-]

Quick question:

 

Is asphyxia modeled in BoS? I know that the aircraft's oxygen system can be damaged, but I'm wondering if that even matters. Will the pilot asphyxiate when flying at high alt with a damaged oxygen system? I've never actually flown at high alt with a damaged oxygen system before so I'm curious.

 

I would like to test asphyxia definitively but of course one of the things the virtual pilot does for you is turn on the oxygen system, so you that isn't possible.

[seafireliv]

Good question.

[Finkeren]

Should be. Haven’t tested it lately, but it definitely worked, when it was implemented.

[Haza]

It usually works for me, however, if I stop playing the Wife releases her tight grip from around my throat and all is well again.

I need to try it in VR to see if it looks or feels any different.

 

Regards

[Field-Ops]

I remember a video long ago of it being demonstrated but that was before Moscow was out. I doubt its gone but I'm not entirely sure. 

[Voidhunger]

2 hours ago, Haza said:

It usually works for me, however, if I stop playing the Wife releases her tight grip from around my throat and all is well again.

I need to try it in VR to see if it looks or feels any different.

 

Regards

Hehe, I know this

[migmadmarine]

If I remember right, the Hs-129B has no oxygen system, so should be easy enough to test with that.  

[SCG_motoadve]

Before 3.001 I got my oxygen shot in a Yak and intentionally I climbed as high as possible and stayed there for a while and nothing happened.

I have not tested it post patch.

[216th_Jordan]

1 minute ago, II./JG77_motoadve said:

Before 3.001 I got my oxygen shot in a Yak and intentionally I climbed as high as possible and stayed there for a while and nothing happened.

I have not tested it post patch.

 

AFAIK it affects the amount of G-load your virtusal pilot can take. He will not blackout at 1g AFAIK, which would be very nice if you would gradually lose sight/ability to manouver.

[Venturi]

It should incapacitate your pilot if he's above 6km or so without supplemental O2, regardless of G's. Maybe not the best suggestion on a computer game forum, but try hiking at 3km or higher, and you'll see what the effects are even at that low altitude.

[ZachariasX]

You don‘t have to go to 6000 m to feel the effect of hypoxia. If you go up fast (like in a jet or Mustang) you will most surely pass out and never wake up.

 

Depending on your tolerance to hypoxia, 4500 m is about where things get really dangerous. You will not notice this normally, as you will feel comfortable. Only if you are very lucky you notice fading colors in your vision and narrowing field of view, kind of like in high g pulls.

 

If you spawn in the Henschel at 6000 m you cannot expect to last longer than a minute.

 

Edit: Just took the Henschel to 7500 m where her limit is. No problems there. (no invulnerability checked...) So, no, no need for oxygen in this game.

Edited April 9, 2018 by ZachariasX
Added info

[56RAF_Roblex]

I remember discovering that DCS models it and you have to manually switch it on.  I could not work out why my graphics was going blurry and doubling :-)

[catchthefoxes]

 why aren't oxygen masks modeled? 

[Blutaar]

There is a term which is called "Time of Useful Consciousness" in aiviation. 

 

"It is the period of time from the interruption of the oxygen supply or exposure to an oxygen-poor environment to the time when useful function is lost, and the individual is no longer capable of taking proper corrective and protective action. It is not the time to total unconsciousness."

 

At 6000m you shoud have plenty of time according to this picture below or did i misunderstand something?

 

Edited April 9, 2018 by Ishtaru

[ZachariasX]

It makes a difference how fast you go to altitude. In a quick climb, you have much less tolerance than when gradually going up, like climbing on a mountain.

 

This way you can walk up to the summit of the Kilimajaro and you will not pass out. you will notice getting „less fit“ plus you might experience altitude sickness in a way of severe discomfort. But you will not getting increasingly happy and impared mentally like you would in an aircraft.

 

The body can adjust to a lot, but you gotta give it some time. Thus, you should take that table with a grain of salt. It is very plausible what is lised there, but but circumstances might not favor you living up to school book values.

 

The „lack of oxygen“ will be important on planes like the Tempest V, where exhaust gases enter the cockpit and you are compelled having a breathing system unless you want to die of carbon monoxide poisoning even if you are low enough to mow the lawn with your propeller.

For practical purposes, in aircraft expect crew start to have symptoms of altitude sickness from 12000 ft and up. Depending on the individual. „Useful consciousness“ is not useful to operate an aircraft, much less fighting. Anyone without oxygen is gambling his life higher up than 16000 ft. 

[Blutaar]

Hmm i dont know how it changes while climbing but it makes sense what you are saying. I guess this table is for planes where the planes pressurisation fails at certain altitudes. But it shows how short the time can be when flying really high. At 30-35k feet you have to be really quick with your oxygen mask. Thats kind of frightening isnt it? 

[ZachariasX]

10 hours ago, Ishtaru said:

Hmm i dont know how it changes while climbing but it makes sense what you are saying. I guess this table is for planes where the planes pressurisation fails at certain altitudes. But it shows how short the time can be when flying really high. At 30-35k feet you have to be really quick with your oxygen mask. Thats kind of frightening isnt it? 

It is. They drop you from an airliner, you will not be awake for most of the fall. Maybe you wake up before impact, maybe you're frozed dead, depending on your clothing.

 

The problem with all of that is, is that you're not "ok" until you suddenly pass out. You are getting progessively more stupid. Eventually, you reach a level, where you cannot saturate your blood with oxygen enough to even supply you with the oxygen needed for basic functioning. If that happens fast, you feel the happyness of hypoxia. If you remain for some time above the zone of where you are not suplying enough oxygen with normal breathing, you start to experience discomfort.

 

What you can see in the chart posted is what happens if you suddenly reduce pressure to the corresponding altitude. In all cases, you are still drawing from a system that is "full" of oxygen and you eat up that budget until you are getting at an equilibruim with the now low pressure. The less pressure you have the faster that will go. Looking at the table you can see that you WILL pass out at ANY of the altitudes listed, starting from 20'000 ft. 

 

Now translate this to what happens when you fly an aircraft to that altitude. It means that you cannot get to 20'000 ft and expect 30 minutes of "functioning", as you already spent some time losing oxygen pressure in your system while getting to 20'000 ft. You can see the quick drop in time left above 20'000 ft because that is where you are not breathing enogh while sitting (remember, you will not have the suffocating feeling as you exhale carbodioxide) even though you theoretically could.

 

The death zone (also applicable for mountain climbers), where you cannot saturate the blood with oxygen sufficiently even when hyperventilating, is a fair bit higher, above 23'000 ft and it is nicely shown on the table. So I shouldn't be able to fly the Henschel at 7'500 m for 10 minutes.

 

If you climb Mount Everest (and you are fit!) you reach this point and then you know you have 48 hours and you will be DEAD at that altitude, as from then on, you're drawing entirely from internal reserves. You can only last that long because your body could adjust to those extreme conditions (you spent weeks in the base camp) and is not functioning normally anymore, most of your system are shut down just to forestall imminent death. If you go up quickly, the body doesn't shut down in that way and you are drawing oxygen much faster. As a climber on Everest you then must reach the summit in high pressure conditions or you will be dead. Sudden low pressure will kill you (half of all fatalities there are due to that effect, even bringing oxygen will not be sufficient then).

 

For practical purposes in flying, you knowing the limits, is that when you are for instance crossing the Rockies and you don't have oxygen for all PAX aboard your Piper and you cruise at 14'000 ft, then you might make life miserable for yourself (if you don't use oxygen) as well as for your PAX. It is at first a question of comfort. Now, since you're already at 14'000 and you see that there's some clouds, maybe crossing the mountains over there, adding some thousand ft... it goes well after all, right? you're "functioning". As a scuba diver crossing 100 ft depht "and nothing happened" why not just a bit more? You're happy after all? So what may seem a question of comfort is essentially a question of safety. Essentially you're making yourself stupid while bringing yourself in a progressively dangerous situation. You do that, you don't age well as a pilot.

 

That reminds me of an instructor when I did my glider rating. He was once asked "how high can a glider go?"  and his reply was "That is simply a question of intelligence."

 

[Blutaar]

7 hours ago, ZachariasX said:

What you can see in the chart posted is what happens if you suddenly reduce pressure to the corresponding altitude. In all cases, you are still drawing from a system that is "full" of oxygen and you eat up that budget until you are getting at an equilibruim with the now low pressure.

 

But would the oxygen not be sucked out in case of decompression? I dont say that hypoxia dosent happen at lets say 20000 feet (6000m), dont get me wrong here. I saw a video from an airline pilot who talked about rapid decompression and thats where i got the charts from. I just thought that at 6000m you should have more time then a minute or so.

 

23 hours ago, ZachariasX said:

If you spawn in the Henschel at 6000 m you cannot expect to last longer than a minute.

 

The Video i got the info and chart from is from a guy named Mentour Pilot and he explains all sorts of airliner related stuff and what procedures pilots have to do and so on. Here the Link to the video about rapid decompression where he talks about hypoxia at around the 3 minute mark: https://www.youtube.com/watch?v=D7ECAgv-R48

 

7 hours ago, ZachariasX said:

The death zone (also applicable for mountain climbers), where you cannot saturate the blood with oxygen sufficiently even when hyperventilating, is a fair bit higher, above 23'000 ft and it is nicely shown on the table. So I shouldn't be able to fly the Henschel at 7'500 m for 10 minutes.

 

Sure you shouldnt be able to do that and i dont say you should. But according to the table you could be able to fly the plane for around 3-5 min before reaching the point where you cannot fly the plane anymore. Thats i guess the reason why it is called "Time of Useful Consciousness" which is not Time to Uconsciousness. How one could reach that alt in the first place without the effects of hypoxia in a Hs 129 is another story of course.

 

Qouted from Wikipedia:

 

"Time of useful consciousness (TUC), also Effective Performance Time (EPT), is defined as the amount of time an individual is able to perform flying duties efficiently in an environment of inadequate oxygen supply.^[1] It is the period of time from the interruption of the oxygen supply or exposure to an oxygen-poor environment to the time when useful function is lost, and the individual is no longer capable of taking proper corrective and protective action. It is not the time to total unconsciousness. At the higher altitudes, the TUC becomes very short; considering this danger, the emphasis is on prevention rather than cure.

For orbital altitudes and above, that is, direct exposure to space, 6–9 seconds of consciousness is expected.

 

The table below shows the average of TUCs recorded over a number of years for a group of healthy, young military pilots at rest during and immediately before exposure to altitude. The TUCs for any given individual may differ significantly from this. Aerobic exercise during the TUC period will reduce the TUCs considerably, so will exercise immediately prior to the TUC as this induces an oxygen debt prior to exposure."

 

The shown table differs slighty from the one i posted. And just to make it clear. I dont think that the table shows guaranteed numbers for everyone, everywhere and everytime, more a rough estimate for fit people. Or that anyone would be safe flying high wthout oxygen for a certain time. And what you say about climbers, i am sure your 100% right. And it is interesting what the human body can do even when its limits are reached.

 

7 hours ago, ZachariasX said:

That reminds me of an instructor when I did my glider rating. He was once asked "how high can a glider go?"  and his reply was "That is simply a question of intelligence."

 

Nice one!

 

edit: btw, thanks for taking the time and responding.

Edited April 10, 2018 by Ishtaru

[blockheadgreen_]

On 09/04/2018 at 9:52 PM, ZachariasX said:

IThe „lack of oxygen“ will be important on planes like the Tempest V, where exhaust gases enter the cockpit and you are compelled having a breathing system unless you want to die of carbon monoxide poisoning even if you are low enough to mow the lawn with your propeller.

I thought was a problem only affecting the Typhoon, as forward of the cockpit up to the firewall the structure was lengthened and revised, so you'd assume they'd have done some sealing work to remedy that.

[Field-Ops]

From Dev Diary # 89:

 

Quote

 

Every aircraft in BOS, except IL-2, is equipped with an oxygen system. It’s designed to provide normal breathing for a pilot on high altitudes. Flying higher than 3000m with a malfunctioning oxygen system or without one is dangerous due to chances of falling unconscious and lowered tolerance to overloads.

Soviet planes are equipped with KPA-3bis open type oxygen devices. He 111 have similar systems while all other German planes in our game have lung-governed oxygen feed devices. The first type delivers pure oxygen directly while the automated lung-governed systems mix oxygen with the surrounding air and feed it for breath-in only. Accordingly, such devices spend different amount of oxygen on different altitudes.

Oxygen is stored highly pressurized in special tanks. Every plane has a manometer to control the use of oxygen. Normally there’s enough oxygen to gain altitude and maintain flight on reached altitudes for a long time; some planes have so much oxygen on board that it’s basically impossible to spend it all on one fuel tank.

In case if the oxygen system is damaged it is highly recommended to avoid high-g maneuvers and descend to 3km and lower.

 

 

[ZachariasX]

13 hours ago, Ishtaru said:

I just thought that at 6000m you should have more time then a minute or so.

 

It is true that you (if all fit and healthy) probably last longer than "a" minute if you have a rapid decompression at 6000 m altitude. But given you are already in a dire situation, these additional minutes you might have are not the credit you should take for granted. And you might be doing very bad much before that already, but you cannot simulate pain and discomfort (we better not), so for a game, I would be rather conservative about the hard limit here.

 

There are different ways to model the progressive degradation of your abilities. You can start with having fading colors, change of FoV no more narrow/zoomed, or even hav "zoom in and out" while you are still allowed to move the stick and levers in the cockpit. Then later you will black out.

 

2 hours ago, Field-Ops said:

Every aircraft in BOS, except IL-2, is equipped with an oxygen system.

 

I just did the test with the IL-2, taking her to 8'300 m. The pilot is fine. But I don't really mind that hypoxia doesn't seem to me modelled (according to the tests I did). Up where you really need oxygen are the 109, and most of the rest are usually mowing the lawn. In a ETO theater, hypoxia will be an important factor. Besides, in this game you cannot make errors in handling the oxygen system. This way it is just "there" making you able to ignore altitude effects in all planes except the ones that are to be flown near treetops. So indeed, why bother. (If you can shoot down a 109 @ 7'000 m in an IL-2, that should be worth 5 time "Hero of the Soviet Union".)

[LukeFF]

The M41 Il-2 has an oxygen system.

[II/JG17_HerrMurf]

There is also the very real possibility that oxygen is modeled and the Hs 129 has had it (digitally) installed inadvertently which would give the stated result as well.

[E69_geramos109]

Is very funny to find a I 16 at 7k on this game with open cockpit hahhaa.

 

[ZachariasX]

On 11.4.2018 at 11:02 PM, II/JG17_HerrMurf said:

There is also the very real possibility that oxygen is modeled and the Hs 129 has had it (digitally) installed inadvertently which would give the stated result as well.

It equals "hypoxia not modelled". But ais said, I think that's ok.

[LukeFF]

6 hours ago, E69_geramos109 said:

Is very funny to find a I 16 at 7k on this game with open cockpit hahhaa.

 

 

The I-16 has an oxygen system

hahhaa

[ZachariasX]

I guess I‘d be happy NOT having oxygen in an open cockpit at 7k m, as it surely puts one out of that misery.

 

I haven‘t found anyone flying above 1500 m in open cockpit (even when it‘s warm in the location you took off) for longer than 30 min voluntarily. It is a pain, honestly.

 

But if you are used to that like Udet, as you didn‘t know anything else, it might not be so bad.

https://m.youtube.com/watch?v=A_nZosMbnZg

Different times, different people. 

[II/JG17_HerrMurf]

7 hours ago, LukeFF said:

 

The I-16 has an oxygen system

hahhaa

 

That’s what I thought but I couldn’t remember for sure. All those early B-17 waist gunners were essentially in the open air and on oxygen. I’m sure it sucks but it can be overcome.

[Venturi]

On 4/9/2018 at 10:56 AM, Ishtaru said:

There is a term which is called "Time of Useful Consciousness" in aiviation. 

 

"It is the period of time from the interruption of the oxygen supply or exposure to an oxygen-poor environment to the time when useful function is lost, and the individual is no longer capable of taking proper corrective and protective action. It is not the time to total unconsciousness."

 

At 6000m you shoud have plenty of time according to this picture below or did i misunderstand something?

 

Your blood's hemoglobin saturation reaches equilibrium with the surrounding air within a minute or two at the most. That means that at a atmospheric pressure of 6km altitude, (Everest base camp), you are at 45% of the sea level oxygen pressure. There are additional physiologic factors which reduce the oxygen pressure at your gas exchange units in your lungs even further beyond this point. But suffice to say that you require a hemoglobin saturation of at least 80% to function, this corresponds to about 4.2km altitude for a healthy young adult.

 

Bottom line, you will begin to slowly die if you do not quickly die at 6km, and it will happen faster as you go up. Whether or not you immediately pass out, which is simply an indication of widespread and serious brain malfunction, is largely a function of how much reserve your body has and how hard you are physically or mentally working. If you are old, or smoke, or have had lung surgeries or infections in the past, this process may happen at even lower altitudes. Young fit pilots may last a little longer than people a decade or two older than them. And over the course of weeks your body will make some remarkable physiologic adaptations to be able to deal better with the reduced oxygen pressure. But beyond a certain point human life at high altitude is time limited, it is only a matter of time before you ptfo (and if you do not descend, die). By the way, before you scoff, people die of altitude sickness every year, even at altitudes of 3km.

 

Do you ever wonder why trees do not grow above 3km? It is not because of the cold. It is because the partial pressure of carbon dioxide is not high enough.

Edited April 24, 2018 by Venturi