"Happy Dog" wrote in message
news
"T o d d P a t t i s t" wrote in message
"Ian Johnston" wrote:

That's a real feat. Without acclimatisation training, which, among other
things, increases hemoglobin counts, it's hard to stay usefully awake
after
a rapid ascent to that altitude. If you used an oximeter, I'd be
interested
in the readings. Did you notice any of the usual effects of hypoxia?

moo

I flew a glider to over 29,000 feet with an A-14 diluter demand system and a
pulse oximeter. It showed a solid 98% SpO2. I have flown to more than
38,000 feet with an A-14 and felt fine but I didn't have a oximeter.

The military systems like the A-14 are good to 38,000 feet according to the
manuals. Above that, a pressure demand system is needed like the US Navy A1
or the USAF A15 with matching pressure demand mask. The pressure demand
system is good to over 50,000 feet, again according to the manuals. The US
Navy A1 system manual specifically says normal SpO2 to 55,000.

Note that a pressure demand mask is very hard to breathe through below about
20,000 feet because of the effort to work the double check valves.

Bill Daniels