I've seen a lot of backpacks go through as carryon. As a warning - if you've EVER used it for camping, check every pocket carefully for a leftover knife, aerosol can of anything, or anything else that the TSA could call a weapon. It's very easy to make a serious mistake. One time I was sweating a bit with a daypack that I've used many times for hunting with my handloads. I got the complete check, including swabbing down the pack for explosives. I was concerned about powder residue from the ammo. They didn't find any.
