So the simulated decompression is more benign than the real thing?
So the simulated decompression is more benign than the real thing?
It was done at a simulated FL 270 and already impressive, let alone if it happens at FL 400
Fletio_Flyer wrote:
wait until it really happens, when people probably even can’t find their own mask in complete fog.
Actually, it does happen now and then, so the reaction of the passengers should be well understood.
Speaking about finding out how your body reacts to a reduction of oxygen level. Short of a simulation in a pressure chamber, how save would you consider a self-test with two pilots, one on oxygen and climbing according to a preset plan, the other one “experimenting” with their reactions, trying to solve a pre-defined “puzzle” and on the next flight, changing roles, i.e. the other pilot flying on oxygen, while the other can monitor their experiences?
I’m thinking about doing this soon in the club C182 before I take non-flying passengers with me on flights that might involve oxygen.
Patrick wrote:
how save would you consider a self-test with two pilots, one on oxygen and climbing according to a preset plan
I think it’s safe as long as you monitor the O2 levels of both the pilot and the passenger.
Why do you want to experiment with it? It’s a fact that human performance deteriorates by lack of oxygen.
You might perform well without O2 at say, FL150, but that doesn’t mean you can always fly safe at FL150 without oxygen.
I think the only thing that matters is that you are able to keep your O2 saturation at a safe level (> 90%).
You need supplemental oxygen for that.
how save would you consider a self-test with two pilots, one on oxygen and climbing according to a preset plan, the other one “experimenting”
I’d say no. You’ll miss all these little signs, that people can expose differently. Only a trained expert can point you to it. You’ll need to have appropriate tests too.
I remember one of the guys had to draw a line from 1 to 2 to 3 etc, to produce a nice drawing. Normally fun for a 6 years old. It took him ages to find the next number. In the end he was drawing on his pants. When asked how he was doing, we got a big smile and thumbs up. The doctor that accompanied us, told him to put his mask on. He ackowledged, but didn’t do it. On the second advise, again a big smile but no show. We had to do it for him.
OK,OK, that was FL 270, and it is not 100, 120 or 150, but still……..
I learned that day not to mess and look for borders.
Remember too, what you seem to manage today can be impossible for you to achieve tomorrow. Condition, stress, fatigue, food to digest, too little drinking (you don’t want to pee,dont you) etc., all these things count.
That’s my two cents.
Fletio_Flyer wrote:
I learned that day not to mess and look for borders.
lenthamen wrote:
You might perform well without O2 at say, FL150, but that doesn’t mean you can always fly safe at FL150 without oxygen.
lenthamen wrote:
Why do you want to experiment with it?
I’m curious how and when I start reacting to it and I find that knowledge somewhat useful. To be clear, I don’t want to apply that knowledge to every day flying at high altitudes without oxygen, that’s not the point. But next to being simply interested in this, I also find it useful info for emergency cases when oxygen might not – for whatever reason – be available to a) have a rough idea of the level/s this would become an issue for me and b) have a rough idea of the signs leading to it – like bosco saying he’ll usually feel quite miserable. Again, these are all not waterproof limitations used for normal operations, but I believe they can be parameters helpful in an unplanned situation.
Here is a fantastic example of the effect of Hypoxia, which fortunately ended well.
At the time of the incident, the aircraft was somewhere around FL300 or higher (at a point they are cleared to descend to FL260).
Altitude to set Oxygen flowmeter
When setting the flow at oxygen bottle flowmeters which one should it be ?
I was thinking of DENSITY ALTITUDE since this is the “true” altitude your body is in (at unpressurized cabins) based on barometric pressure, temperature etc.
I read this out by setting correct local QNH on the Shadin ADC (Air Data Computer) of the aircraft and as we all know at FL120 you may well be at e.g. 14,000ft. Density altitude depending on conditions.
Am I right in this thinking ?
From one of my flights cruising at FL160
No, you should use the pressure altitude. The oxygen intake depends on the oxygen partial pressure. Temperature isn’t a factor
If I understand your procedure correctly, you shouldn’t use the QNH. At the standard (flight level) altimeter setting, indicated altitude corresponds directly to pressure.
