Boeing A319 sitting in seat C on the aisle.
After trying to shoehorn my size 50 as a personal item, I have downsized to a 40 which fits nicely on this plane. It was a little snug on my last flight which was a 737-800. I had to orient it north-south. It exceed the space a little, but the flight attendants didn’t complain.

After trying to shoehorn my size 50 as a personal item, I have downsized to a 40 which fits nicely on this plane. It was a little snug on my last flight which was a 737-800. I had to orient it north-south. It exceed the space a little, but the flight attendants didn’t complain.
