I can fall asleep if I'm really, really tired. Other than that, nothing will do it.

I try to put in earplugs and use a mask to make sure that once I fall asleep, I stay asleep.

However... I talk in my sleep. How horrible! One time I had a dream that I was on a plane that was crashing and I think I might have screamed out loud because I woke myself up. I felt too funny about it to ask anybody if it was out loud!!! I wonder if I've ever said anything strange in my sleep on a flight. I definitely talk every night so I imagine I talk on the plane, too.