I've done this. We checked with the airlines first, were told that PFDs with CO2 cartridge were allowed, BUT that we needed to be certain to declare them to the TSA folks. We did all that, had only a little delay because the first person we declared the PFD and cartridge to was uncertain, but he checked with his supervisor who knew the rules and allowed the PFD through. We didn't have to remove the CO2 cartridge. We also took an EPIRB which I expected might have caused more of an issue with its batteries and wiring, etc. but it was also allowed through. This was flying from Central California to Seattle to deliver a friend's boat. Our experience overall was a positive one. I'm one that's glad they check this stuff.