I have a question concerning hypoxia; I did a search on this site and couldn't find any previous threads on this subject. I retired from the USAF in 2001 after many years of flying on the AC-130U Gunship; big fun, I still can't believe they paid me to do that job, haha, I would have paid them. Since my retirement I've been doing "contract" work flying over the friendly skies of Kosovo for the US KFOR and NATO. Lately we've been spending a lot of time around 13K MSL for up to 6+ hours unpressurized while flying over our targets. We have the wimpy civilian nasal cannula type O2 system on board. I've noticed that I'm experiencing hypoxia while climbing through 11.5 for 13; when I use my O2 I feel better but not 100% better. About 2 years before I retired I was diagnosed with and received a waiver for mitral valve prolapse with AI. I'm wondering about a couple of things here. Is it normal to experience hypoxia starting at 11.5? Could this be related to my heart valves? Is there some sort of test that I can have done at Hurlburt to measure the O2 in my blood and find out if there is a problem with that? Thanks in advance for answering my first post.

BadMonkey130U

[ 21. March 2005, 22:52: Message edited by: BadMonkey130U ]

You should NOT be feeling hypoxia that low, I've flown at 12.5 for 4 hours, with no problems, and flown at 17.5 using the cannulas for 4 hours and have felt fine. Do you smoke? Just look back at your altitude chamber flying see what you do that could cause it. The docs will have to answer the last part.

Comanche

Thanks comanche. I don't smoke, I drink maybe 1 beer every 2 weeks and I feel great. I've only experienced hypoxia before this while attending the chamber. On the guships we had to be on O2 before we went through 10K unpressureized so I never experienced it there.

Badmonkey130U

I ski at 10500 all day long and have no problems, just sounds funny at 11.5 you would feel anything. I'm sure you know the FAA requirement is above 12500 for 30 min you need it. You can fly all day AT 12500. I'm guessing you should get a check up.

Badmonkey

Sorry I re-read your post, I thought you were staying at 11.5. If you are at 13 for that long I could posibbly understand, but again whats 500 feet? 12.5 and 13. If you feel it while going through 11.5 try putting in the cannulas early, say 8.

Hope it goes away!

Comanche

Hard to say what is going on, or why. You CAN be hypoxic at that altitude. Most aren't, but it's possible. Valvular heart disease makes your heart less efficient at pumping blood around - namely, to your brain. If you add that to lower levels of oxygen, it is possible that you could be getting hypoxic. Now, you wouldn't have gotten your USAF waiver if it were that bad...but you could be getting worse. I would look into it.

Thanks F16PilotMD. I'll go to the Hurlburt clinic tomorrow and get it checked out.

-BadMonkey130U