Well, from my experience, having worked for 2 airlines, they don't accept rats in the cabin any more. They have rats escape and had to evacuate planes because the danger of a rat chewing on a cord. This was in Norway. I don't know how the practice is in other countries.
wow, I don't know, I was asking myself the same question when I first got my rat, I think they do, but I am not sure. I was asking myself that question becasue I visit my Grandparents ever year bymyself in Washington. It would be so cool to take Templeton on an ariplane to my Grandparetns house!
Delta airlines allows ferrets, so maybe they allow rats too. I dunno. The problem though (and this is the case with just about any airline that allows pets in the cabin) is that you have to call months and months ahead of time just for a chance to be able to fly with your pet, as they only allow a limited number of pets in the cabin at a time. Delta I think only allows 2 animals at a time with no exceptions. I could be wrong though.