We are camping at FW and are flying in. We can fit all our equipment in a trunk, and the trunk is the appropriate size that the airline allows. My question is how to keep it closed. It's basically a foot locker, so the "clips" that keep it closed aren't the best. Will the airline allow us to zip tie it, or is that the same as locking it? I know you can't lock your luggage. Any suggestions? Thanks!