In the article that I read, the FAA said that the napping had a
detrimental affect on performance. It meant the controllers were
groggy when returning to the scope.

So maybe the FAA has their own study.

If they do, I'm unaware of it. However, length of nap was important, as
well as when (and how) they were woken up. Being woken up in some
phases of sleep is better than others.

Jose
--
There are more ways to skin a cat than there are cats.
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