In reply to Tim Chappell:
Highest sleep recently was a result!
Flying economy from Houston to Heathrow, we are all packed in like sardines, and I was in the middle seat. On my first visit to the toilets I noticed the entire back row of seats was empty.
I had a wee word with one of the cabin crew and then I did the generous thing and gave the people on either side of me a bit more elbow room
Arm rests up, stretch out flat on the back seat, slept like a log back to Heathrow.