At 24,000 feet in the cruise, you notice that the Flight Engineer is surreptitiously strapping himself into his seat. You are puzzled and a little worried. Why is he doing this?
a) He is anticipating a little turbulence ahead
b) He has spotted a potential malfunction and is preparing for the possibility of some red card drills.
c) He can't keep his eyes open any longer and he is strapping in to avoid waking the Captain & Co Pilot by falling forward on to the centre console.