However, whenever the aircraft is operating above flight level 450, the pilot, or one of the pilots, seated at the controls of the aircraft must wear an oxygen mask that is properly fitted and supplying oxygen

That would have meant that an N-reg Concorde PIC would have been on O2 for most of the flight.

Risk assessment in aviation always includes probability and severity. While the severity of rapid decompression is very high, probability of happening it exactly when one pilot is out of the cockpit is very high.

There has to be some common sense in aviation.

By all rights, if a rapid decompression occurred at altitudes above 50,000 ft, one would need a pressure suit to survive.

https://en.wikipedia.org/wiki/Pressure_suit

The rule in FAA-land is F410 which does affect bizjet operators. We're trying to change it, but it doesn't effect the airlines, so the FAA isn't interested.

GF

So to confirm then....it is NOT regulatory practice in most ICAO states.

"Last week a crew had the hose come off the mask during removal and flailed all over the cockpit."

Sounds like a good reason to check functionality of the system out before you go flying. Pretty much SOP in the FAA Part 121 world. The full face masks as used by a number of airlines, are a little more difficult.

"Sounds like a good reason to check functionality of the system out before you go flying"

Interesting take on it.

I suspect the damage is being done by the constant removal and replacement of the masks. Chicken or egg?

oicur12.again

I think you may have a good point there. A certain Asian airline requires the masks to be tested and re-stowed before every flight by the flight crew. There have been countless occasions where the re-stowing was incorrectly carried out rendering the quick don function to be lost!

In my company we check the operation (flow and oxy rate etc) while still in its cubby, but don't physically remove it.

I pull mine out, clean it with a sanitizing swab, and put it on, check o2 flow and communications, then give it another wipe with the sanitizing swab and stow it. That way I know that if I need it, it's ready to go, o2 is there, the microphone is correctly connected and the hose is not in a snarl. I don't know how many times I've pulled it out and the mic is not connected correctly. In our airplanes the mic plugs into a small panel which is hard to see and hard to reach, consequently the mask mic plug often gets mistakenly plugged into the hand mic jack. Finding a ball of snarled hose is not uncommon. I once found the mask half full of frozen coffee.

I'm not going to say that these things happen all the time, but they're common enough that there's at least some chance that my quick donning mask isn't going to be quite so "quick donning" if I need it to be. So I preflight it.

The rule in FAA-land is F410 which does affect bizjet operators. We're trying to change it, but it doesn't effect the airlines, so the FAA isn't interested.

Oh yeh? Most private biz-jets most likely do what they like: or file FL410 as max.

To those who say the quite regularly deploy the O2 max and re-stow it; I salute you. It has never been a teaching point in nay of my TR courses. I learnt how to do it using initiative & an engineer. IMHO a quick poll of those who know how to re-stow an O2 mask would show a very small %. Surely, if there is a need to use and re-stow then crews should be instructed how to do so.

On the types i'm rated both flow and microphone can be tested while the mask is still stowed. And yes, we have to do that before the first of our flights of the day of course. But regularly taking the mask out and use it is not part of the normal test, and since we do not have to use it during normal operations re-stowing isn't trained, let the engineers handle that, it is part of their job. It is the same in the simulator. Use it, roughly place it close to its stow position and let the simulator engineers stow it after the session. My company pays for that after all.

So, because of incorrect re-stowing, the solution is to re-stow it every day?

I agree with Denti, let the engineers handle the re-stowing of the oxygen mask. As a pilot, your main duty is to stop the oxygen flow (usually by closing the left door and pressing the test/reset button) when you don't need the mask anymore and verifying it has indeed stopped.

CanadianAirbusPilot;
One carrier in Canada used to require it when one pilot left the FD. That same carrier now requires both pilots to wear O2 masks when above FL410 and the masks are the quick-donning type.

I suppose that I should clarify that I'm dealing with a little different setup than the Boeing and Airbus masks. The masks, together with the coiled hose is hung from the cockpit sidewall from a quick release loop, so everything is exposed and subject to getting knocked around by flight bags or the odd foot. And being out in the open the mask is subject to catching debris, such as the aforementioned spilled coffee. re-stowing the deal isn't really a maintenance procedure, more a matter of hanging the hose so the loops aren't twisted, and won't turn into a bird's nest if the mask is grabbed in a hurry. Although, apparently, some of my co-workers can;t figure that out out, or can't be bothered.

RAT 5

The problem is "doing what they like" cause normalization of deviation in ignoring the rule. Some stay at F410, some use oxygen above F410, some, no doubt ignore the rule as being out of date. The stats of high altitude loss of pressurization support changing the rule or deleting it entirely. The oxygen masks in a side wall cubby (Scott EROS) weren't designed for constant use and constantly being undone and restowed, hence the test function which doesn't require removing the mask.

GF

Here are some additional references.


Operators Press For Relief From Oxygen Mask Rule | NBAA2014 content from Aviation Week

Let's just hope none of you jokers ever have to use your mask because you won't even know if it's there or where it is.

So in response to the OP, we have USA and NZ only. Anywhere else?

Forgive my ignorance here as a controller, but a G5 driver told me a couple of years ago that if they depressurise and don't respond within a set time limit up in the FL400s the aircraft will deviate and descend off track automatically? And bang out an emergency ADS report for non radar environments advising of same? Is this, like ADS/CPDLC, fairly standard equipment on the latest biz jets?