Sounds like fun.

I used to share a house with a guy like that. His snoring would reverberate throughtout the whole house. My room was next to his and at night it would keep me awake for hours. So after a while I came up with a cunning plan. I would 'accidently' bang on the wall a couple of times, this would either disturb him and he'd roll over, or it would wake him up and he'd wonder what was going on. This would give me plenty of time to get to sleep myself before he started snoring again.

Maybe you could have tried shaking or banging your seat a bit, might have disturbed him, at least you could blame it on turbulence if he gave you a funny look.