Under the seat
The most worriesome parts of the trip were at certain security checks where we had to take her out and hold her while the carrier went through the scanner. We had put a kitty halter and leash on her, which she hated even more than the carrier.Still, it was scary standing there holding a squirming cat in an enormous and chaotic airport. The security people seemed remarkably clueless about this and would fire questions at us and demand documents while the cat freaked out and the cat carrier sat there on the scanner belt, already approved for flight but just beyond arm's reach.
Susu was anxious at the beginning of the journey, she was panting with her mouth open, which is a strange and disturbing thing in a cat. I can't say she really got adjusted to traveling but she basically wore herself out after several hours and fell asleep. When we got to the airport hotel in LA she pulled the Invisible Kitty act, vanishing for at least an hour before we figured out that she had climbed up inside the box spring. But by morning she had recovered enough to investigate the room.
After that it was just one more short flight to Phoenix and a well-earned rest for all concerned.
Flying Cat Tips:
1. I found putting a puppy training pad in the bottom of the carrier completely pointless. It just got wadded up in a big lump in the corner. Susu was so stressed out I don't think she could have emitted any waste products anyway. In fact, she had a hard time using the litter box even after we settled into the hotel; I think she got pretty dehydrated.
2. Bring something warm to put in or around the carrier (being careful not to block the cat's air supply). Planes are really cold.
3. Get a carrier with a reach-in zipper so you can pet your cat when s/he is anxious. That really seemed to reassure her.