I'm from Canada and yes men here too get kicked in the nuts when it comes to child custody issues.
I had the same round of disputes with my X. She said I was absolutely not to take my son, then 4 or 5, flying.
I took him flying anyways and he really enjoyed it. I snapped a few pictures of him having a good time.
She threatened to take it to court, I just smiled and said see you there. It was one of the few times she couldn't get a lawyer to take up her case. It was just plain and simple not winnable.
As my lawyer said, "If you're licenced and legal to go flying she can't tell you can't take him flying any more than she can say you can't take him for a car ride."
In other words there is no discernable difference between a personal car and a personal airplane in the eyes of the court.
She tried to inject ideas like, oh he’s scared of flying, he doesn’t like the noise etc. All of these were her fears not his and even if he was a bit timid the argument still doesn’t hold. If a child is scared of riding in a car for no good reason you can’t force the parents to walk everywhere. It’s the boogie man in the closet thing. Sooner or later the child needs to face those fears, either by sleeping in their bed alone or going for a car/plane ride.
15 years later my son enjoys going up for rides and often takes the controls under my supervision as he hasn’t gotten his licence yet. His two half siblings from his mothers second marriage won’t get into the plane even on the ground as they think it’s going to spontaneously explode (guess where they got those ideas from.)
There is distinction between being amicable for the sake of the children and giving up on your ideals and values. I would say that if flying is your true passion and what defines your character and person then to agree not to involve your children is the later.