once&future wrote: ↑
Tue Jul 10, 2018 10:41 pm
No arguments on proper techniques for coring sink nor on choice of O2 cannulae. I just wonder what your criteria are for needing or wanting to carry supplemental oxygen. One can argue that it's worthwhile whenever one is going to be over 10K for any period of time, but the extra weight and complexity were enough of a negative for me that I never bothered unless I expected to be over 14K for at least a half hour or so. In my most recent flying in the last few years I didn't go as high as in the old days, but still got to 12-14K several times and never felt like I missed the O2.
The FAA requires oxygen for all pilots above 10,00 feet MSL. A brief
sprint above that limit is legal, but not for long. Argue with the FAA at your own peril (and everybody else's, for that matter). I see nothing in FAA FAR 103 that gives us any extra leeway, there.
Realistically, your personal need for oxygen depends on how high your home neighborhood may be, MSL. I've had seacoast pilots here that are dizzy, with headaches, and puking ON LAUNCH
in our mountains, and no, today is not a good day for you to fly, mate. Sit them down and feed them oxygen, and they are okay again in a while, but I need all that stuff back when I launch, right?
Local pilots who often fly here may be good to about 14,000 feet, but nobody at 14k' is going to leave the lift, usually, so I still recommend oxygen as required.
Having and using oxygen contributes greatly to your confidence and well-being, when 'way up there. Without it, you will soon be feeling anxious and uneasy, but you will not
know why. Euphoria will be the the first symptom, though.
There was a time when I used an O2 cartridge system, like big CO2 cartridges but carrying oxygen instead. One time, on a high mountain flight, the cartridge ran dry, and there was no notice, except for a gauge reading Zero. I did not
notice that. I found I was about 90 degrees off course, corrected that, and soon I was 90 degrees off course again. This was on a glider that would fly in straight lines for several minutes, hands off, so I corrected my course once again. Then I started checking things, and found that I could not count to 30 by threes. I was out of oxygen. I installed a fresh cylinder and all was well again, but except for a great feeling of euphoria, there was no way I could have said anything was off, when my oxygen was lacking.
Now we all know that there is only one Four-Of-Spades in any deck of cards. Check out Mr. Four-Of-Spades in an altitude chamber, and watch how many cards he mis-identifies in this video:
To your good health, then,