Rules in the US about traveling with emotional support dogs. As pointed out earlier, lots of flights over water have other regs.

I have a news article on the latest, up dated 30 Mar 2018

https://www.transportation.gov/individuals/aviation-consumer-protection/service-animals-including-emotional-support-animals

unless it is real....and I mean real don't. flights that are transatlantic have unique rules for all dogs. As a Special Ed teacher fake service and support dogs hurt a lot of people with real needa.