There is a wide variation in of hypoxia from person to person and possibly from day to day in the same person. I had an explosive decompression at 22,000 ft 15 years ago and I had headache for a day, never did have the time to put on the O2 mask, and started an emergency decent immediately to 12,000 ft which was the altitude I flew home without O2. I had, around the same time frame, an O2 malfunction in my glider, spent much of the day at 17,500 with no ill effects. Yet another day at a region 12 contest (remember those) I had obvious signs of hypoxia, even to me, when the flight never got higher than 16,500 and I had a working O2 system. I suspect on the last one I had a kink in the O2 line as once on the ground my thought process cleared up and I tested the O2 system, worked fine. Flew next day with no problems.

I live at sea level and have decided to go on O2 at 10,000 ft. Have not tested my high altitude no O2 capabilities lately, thank goodness. However, about four or five years ago I started doing Bikram yoga daily, which starts and ends with a breathing exercise. I found after about six months of Bikram on my thrice weakling 1.5 mile swims I had changed my breathing from every stroke to every third stroke! My heart rate is also considerably lower, might have some effect.


On Friday, May 19, 2017 at 11:43:20 AM UTC-7, Frank Whiteley wrote:
On Friday, May 19, 2017 at 12:18:01 PM UTC-6, jfitch wrote:
On Friday, May 19, 2017 at 10:21:03 AM UTC-7, gkemp wrote:
On Friday, May 19, 2017 at 8:20:36 AM UTC-7, quietpilot wrote:
Bouncing off a comment from another thread.

a number of we "not in our 40s anymore" pilots are setting the O2 to kick in at 5000 msl.

O2 is cheap. Clarity of mind at altitude - priceless!


Being in the middle of my 40s myself. I recall spending time periodically in various smoke filled rooms when I was younger before the attacks on tobacco set laws in motion. Although I didn't smoke myself, the 2nd hand effects were noticeable even then. Do people who set their O2 to start at 5kmsl think environmental factors were important or just adjusting to the requirements of age in the interest of safety? I start feeling the need about 12kmsl and set it at 10K

O2 cheap? Perhaps in Hobbs, in the midwest all I get are weird looks. I have had an empty tank for years but would like to take the fiberglass stallion somewhere more dynamic eventually and not have to hunt for 02 once there.

Curiously

I remember reading an air force study some years ago where they found reduced judgement in their pilots at 5000 feet. I started using oxygen from 5K from then on.

Gary Kemp (NK)

Flying at Truckee, I would need to turn on the oxygen on the drive to the gliderport, since the pass is 7200 msl and the runway is 5900 msl.

Also the answer must surely depend on aclimatization: going from sea level to 12,000 in an hour is different than your second or third day living at 5900 ft and going to 12,000.

Agreed YMMV.

Back in 1984, I requested organized a civilian chamber ride at Beale AFB for the upcoming PASCO wave camp. During the FL250 decompression, the younger (by at least 10 years) man next to me was to remove his mask as we did it in alternates so we could assist if necessary. He mentioned that he'd been partying in the Bay Area for a couple of days and nights and had little or no rest. Within one minute, he was completely unconscious and rigid from head to tow, like a plank. Only the back of his head and his heels were touching the seat and floor. I put his mask back on and it took a full five minutes for him to regain consciousness. With my mask off, I did all the puzzles and wanted to keep my mask off until I noticed something as I felt just fine and perhaps a little euphoric. I was clearly convinced there was a wide variation in individual response after that experience.

Frank Whiteley