Dogs in Aeroplanes
Well, I have two greyhounds and they have well over 100 flying hours each. Based in Blackpool, they have flown to Jersey direct (3 hours); Western Isles of Scotland; Alderney to Cornwall, etc. Up to FL100, but usually around 3-4,000 feet.
You have to know your own dog, of course, so there are no hard and fast rules. We take large comfortable beds and make sure that they have had exercise before we go flying. They are large dogs, but that's not a bad thing - they don't walk around whilst we are flying! (C172, usually - 1 in the baggage compartment, the other on the back seat).
We don't use ear defenders - they don't seem to mind not having them and they don't like anything on their heads. (How would you keep them on?)
We have also found lots of really good dog walks next to airfields (Donegal, Carenarfon, North Coates, Welshpool, Isle of Man, Oban, Mull - I could go on).
We love taking the dogs with us and they love flying. Far better behaved than kids! Go for it.