Back and I need a rest

Well I can never sleep on a flight. I just never figure out why? Could it be the cramp seats (nope A380 is quite spacious), could it be the distracting interactive entertainment unit then? (have watched Casino Royale 2 times)

I never know for sure

What I do know is that I sure can doze off in a boring training lecture in a small uncomfortable chair.

ps. do go for the upper deck if you taking the A380