I wish I had chanced upon this thread before. I think I read one truly sensible posting which revealed that humans will sleep if sufficiently tired as the poor sentries in WW1 discovered. I would now like to tell the world (including journalists and assorted laypersons) PILOTS ARE HUMAN. This is incontrovertible. At one time I flew on the bucket and spade trade with 7 day rosters comprising 2 days early, 3 days normal and 2 days overnight. Although it was called short haul, two 5 hour sectors with a one hour turn round makes for a pretty long day. If on the final two days you find yourself flogging back over Hungary or Austria at 0300 or 0400 I think you could be forgiven for feeling just a little jaded and fighting to keep the eyes open. How silly when it has been proved that a 20 minutes power nap will give you about 3 hours of alert consciousness. Of course this napping must be properly controlled with appropriate checks and balances. But how much better and safer to reach destination (possibly in grotty conditions) with both pilots fresh and alert than to have one succumb to a micro sleep on final approach. It does happen - I once had to take control from a senior training captain who fell asleep on a NPA at the end of such a sector. It taught us both lessons and the company thereafter were happy for their crews to use controlled power naps.