When we first got chickens, the younger ones easily flew to the top of a 7+ foot fence. Then I heard a lot of racket and found a black orpington had cornered my neighbor's cat on her carport and was terrorizing the poor thing. Never saw a cat with eyes so big. We clipped wings once, and it has resolved the problem. We have one older girl who will occasionally go for a walk in the front yard and come back on her own. She had a friend that would go with her that passed of old age earlier this year. It was funny, they would wait until the two of them were alone, so the younger ones couldn't figure out how they were doing it.