Sunday, February 3, 2008
The Altitude Chamber
Pilots who fly above 10,000 feet above sea level need to be intimately familiar with what is now called Aerospace Physiology, the effects of the thinning of air on the body as you climb to altitude.
When I attended flight school at Pensacola in 1936-37, almost all our training was done below 2,500’msl, much less 10,000’msl. We had a class on high altitude flight, but there was no such thing as an “altitude chamber” where one could experience the physiological changes as one climbs to altitude. It had not been invented yet and most Navy pilots never would fly that high. But, when you left flight school, if you were headed to a fighter, you had to get the training.
There was no “altitude chamber”, so what to do? Once you got your wings and your assignment, you got one last ride. I don’t remember his name, but he was a Marine pilot instructor. He briefed me on my “altitude familiarization” flight. The aircraft was one of two, or maybe three, single seat Boeing F4B biplane aircraft fitted out for this specialized training. It was supercharged, had a recording barometric altimeter to make sure you really climbed up and had a large oxygen tank fitted. You were to breathe from a wooden mouthpiece, which as I recall, you started using about 10,000’msl, or so. The Marine told me that I should look for symptoms of oxygen starvation, check my nails for bluing, tingling in the fingers and the like. As soon as I felt light headed, I should take off my gloves, look at my nails and if they were blue, start down.
So off I went. Passing about 27,000’msl, I began to feel a bit tingly, I looked at my nails, still pink, or maybe some other color. Passing about 29,000’msl, I felt a bit light headed, I, well I don’t really know what I did next. According to the recording barometric altimeter, I climbed to a little over 33,000’msl. All I can tell you is that I woke up in a spin at around 7,000’msl.
When I got down, the Marine seemed satisfied. I was not so happy. I said, “What if I hadn’t awaken at 7,000’msl?” “We’d of had to get a new plane,” he answered.
I was never tempted to set any altitude records after that.
Oral History by Admiral Jackson D. Arnold 2004