What happens to a dog in flight?

[LittleLoves]

I'm curious to hear any stories of those who have flown their pets for longer flights.

We are facing a possible cross country move that would have us fly from the East Coast to the West.

I've gone on Air Canada's site to see what we would need to do to prepare, but I'm so concerned that the Oscar and Lady would be thirsty/scared and the flight would be delayed (causing them to have to wait even longer for drinks)

It did say that agents may give your pet water in the event of a delay, but does that happen often?

Thanks for any info you may have. This is obviously early in the game (hubby's interview is Friday for the job out west) but I want to be prepared.