I flew with a dog and two cats, and they all recovered remarkably quickly. I was expecting a lot more upset. I'd been crate training the dog for months, and really tried to make it as comfortable as possible for her. Still, she's always had some claustrophobia issues, and I figured that the nearly 20 hours she had to spend in the crate (the flight, plus check-in, plus the drive from London to Newcastle) were going to be hell. She seemed just fine, though. We let her out of the crate for a potty break a little bit outside of London, and I was terrified she wouldn't get back in (I was being driven from one place to the next--if it had just been me I would have let her out of her crate for the car ride), but she seemed pretty chill about it. We went for a decent walk when we got to the flat, so that she could sniff, etc, and after that she settled right in.