I did it every year for 20 years, couple different dogs. My current brace of shorthairs started making the trip at six months, they are 12 and 13 now. Portland and Seattle suck! They have done very little in the way of accommodating dogs. Get there early and plan on having to explain to them you will be taking the dogs out for one more potty break before checking them through the TSA process. If you try to game the system, arrive with just enough time, it's your dog that suffers. PDX and SeaTac are the same in this regard. I used either airport based on schedule and whichof mysiblingswanted my truckfortheseason.
Anc is completely different. You still need to be early checking in but then you ask if they will check with the baggage super and find out what time you need to have the dog back. Lots of good dog walking out in the parking area.
On the way up I always had a connection out to King Salmon. The dogs were checked through on the ticket. We always had a couple hours, I would go check with the baggage guys and get the dogs out for a walk and have them back 15 minutes early.
Sometimes had to run them back through TSA, that depends on who I was flying out to King Salmon with. They will let you know if you're going to have to re check the dog.
Have your vet paper work handy, you will need it. Make sure there is no damage to the crate, make sure there is a bolt through every hole that holds top and bottom of the crate together, I've done that dance, most importantly, invest in a couple dozen of the removable zip ties to secure the door because nobody at baggage claim will have a knife or scissors available to let your dog out. The dogs always made it just fine.
