I have a soft flannel bag with a drawstring that came with a purse long ago. I bring that in my carryon and then stuff my puffer coat in it when I get on the plane. It makes a great pillow or I can stuff it under the seat.

For the most part, I put my bug coat in my luggage and wear a hoodie or sweater while traveling. It's just too much of a pain in the butt to manage everyone's coats in the terminal and on the plane (I have young kids so it's not just my coat) and you're usually not outside for long enough for something like 32F to be a problem. If I'm flying to somewhere like Chicago in the winter I'll pull the coats out before we leave the terminal or put them back in luggage before we go through security/check bags.

We just flew from Newark to Frankfurt and they said since the plane was full, only luggage above - no coats.

Anonymous wrote:I always bring my puffy jacket on the plane and use it as a pillow/blanket (depending on the comfort level of the cabin).

This. Unless you are in first class.

I rarely check a bag anymore.

I have a "packable" coat that squishes pretty small so I just take it off before I even go through security at the airport and put it in my carry on.
I feel it would get uncomfortable wearing it for a long international flight, especially if it was a red eye.

Always have them with you in case you get diverted to a airport in a cold weather climate that has steps that you have to use to get down and walk across the runway to get into the airport

We always bring them, but we fly private anyway, so it doesn't matter much.

We wear them to the airport (if needed), then we each put ours in our individual suitcases' outer zipped pocket to quickly pull out upon arrival.