... into those big cushy seats.
What the hell airline do you fly on?! LOL
As far as the generalization goes that someone is sleep deprived and that's a medical condition if they fall asleep on an airliner goes... sometimes sleep deprivation is chosen, not medical.
I'd book insane flight times into and out if customer sites back when I traveled extensively specifically so I *would* sleep through the hell of air travel. And most of that was back before TSA and airport retardedness and even bigger seat pitches than today.
You know, back when the seat recline function didn't start fistfights? LOL.
Work was often also done overnight like most telecom and IT work.
So yeah, sleep deprived on the airliner was a planned event. Finish work at dawn, hop the earliest flight out, and sleep all the way home.
A great way to ignore the idiots and tourists on most flights who weren't flying weekly or more than weekly to customer sites.
Standard business travel briefing: Sit up, shut up, buckle up, and don't throw up. Exit door is there and there. Zzzzz. Best possible use of time.