If I had no other choice than commercial flight, I think I would duct tape a few pampers together and let them wonder what the problem might be.
Oh wait. I just had a better idea. Say the following at the top of your lungs:
I pledge Allegiance to the flag
of the United States of America
and to the Republic for which it stands,
one nation under God, indivisible,
with Liberty and Justice for all.
and when you get to the part about liberty and justice, turn your body away from the pervert in a jerk.