+1 to what ringworm said. I would also point out that occasionally, with full flights, carry-on luggage has to be checked at the gate due to limited space onboard. They tag it at the door of the plane then haul it out and stick it in cargo hold with all the other luggage. Some airlines keep it checked until final destination, others return it at the bridge when de-boarding occurs. Along with a change of socks and underwear, maybe an extra shirt, I carry my optics, rangefinder, camera, flashlights, etc. in a backpack that I can fit under the seat. This keeps me from having to check anything at the gate, keeps sensitive items safely in my hands, as well as helps reduce weight of any bags I checked at the counter. If it'll fit under the seat, you don't have to gate-check. Be sure to check your airline's policy on how they handle gate-checked luggage, as well as how to carry batteries, ammunition, checking firearms, etc. Know their rules inside and out. When booking flights, give yourself a decent layover. I shoot for at least an hour on hunting trips because I'd rather have a longer layover than have a tight layover and my gun/bags not get transferred to the next flight because of a time crunch. Get to the airport early enough to make sure any wrinkles you may encounter during the check in process can be ironed out with plenty of time to spare. Last, but definitely not least, be polite.