I can fall asleep almost anywhere. I routinely fall asleep in the break room at work. Once, I was helping a friend fix his car, and I fell asleep on his garage floor when he went inside to get water.
But in a hot metal tube tearing through the sky, with my neck all kinked? Get out of here, man.
Worst one for me was a business trip to Asia where I worked Friday, went home for a couple hours and then headed to the airport for a 1AM flight. 13 hours on the flight where I don’t sleep at all, landed at my destination at 5AM local time. Had to then kill an entire day and pushed through till 10PM before going to bed. I think it was around 40 hours between beds.