There's this thing that will happen to me when I doze off as a passenger in a car: When I wake up, there's often a split second of panic between the visceral understanding that I'm in a moving vehicle and the slightly delayed recollection that I'm not the one responsible for driving it.

Somehow, this turned into a problem for me when flying (even though I'm not a pilot). I wake up, I instantly know I'm moving at 500 miles per hour through the air, then I have a singular panic of being in a vehicle not under my control. This has only happened once – I haven't slept on a plane since.