Sleeping on flights

[ddubois]

I used to be able to sleep on airplanes, but I lost the ability somewhere around 20. For some reason, I just can't fall asleep when semi-upright, no matter how tired I am, nor how much I try. I've got a long overnight Hawaii -> Boston trip coming up, for which I very much want to be sharp and alert when I arrive. I would be interested in hearing from people who have had the same problem, or any advice people have about falling asleep in this situation.