I read a very interesting article recently, and I can't remember where it was. I'm pretty sure it was one of the magazines.
The pilot concerned was a very experienced ATPL, who was carrying out a high level flight in a glider. He had an oxygen system, but hadn't begun to use it yet. He was keeping a check on his mental state by regularly counting backwards from 100 to ensure he wasn't suffering from hypoxia.
He goes on to explain how he made a series of mistakes throughout the flight, which although he didn't realise at the time, were caused by hypoxia. He had been regularly counting backwards, but towards the end of the flight he'd become increasingly bored with the counting, and had gone from 100 to 50, or from 100 to 80. He'd considered that he wasn't suffering from hypoxia because he was able to count backwards - he had assumed that hypoxia would show as an inability to count backwards, not as a lack of enthusiasm for it.....
Maybe someone else will remember the article and be able to point us to it, because it's very relevant to the thread?
FFF
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