We took our 2 children (6 y/o and 3 y/o) on their first trip on an airplane last September. No problems at all. But I did read a post on the message board from a mother who had a CAH child that got motion sickness from the plane ride and started vomiting. I was glad I read that before our trip, because I had never thought of motion sickness being a problem. It is good to think of all of the possible scenarios. But as far as the trip to disney....I would make sure you have several copies of  letter from your child’s endo saying how to treat in an emergency and also the emergency cards that the CARES foundation sent out. They are wonderful! Have fun!!!