Well, of course yes, flying can lead to high eye pressure because of the gravity. Maybe you feel strange about it, but it actually occurs. First, you should know that when you take the fly, there will have gravity, and it can give you a kind of pressure on your eyes, when it takes off. In that way, high eye pressure will occur to your eyes. And eye strain can be another one. And for some people whose eyes are sensitive, it is very normal to have red eyes or headache when they have flying, because of the high eye pressure. Especially for some people who have taken some eye surgery, it can be dangerous to take a plane. So just be careful about it.