It all depends on how much risk you are willing to take. Most airports have Valet's outside that you can give your luggage to who will check it in & have it put on the plane. That way you don't have to pass any security points carrying the luggage that you have your stash in. Just don't put it in your carry on luggage. Vacuum sealing would be a big benefit to you. The worse place to keep it is on yourself or in your carry on bag. Those are the first places they will check.