Carry On Restrictions
Carry on restrictions change just as frequently as flights in many places. The TSA and airport security have their own carry on restrictions that focus more on what you can and can’t have, while airlines have their own carry on restrictions for the size of bag and such that you can carry. The idea is to insure that nothing that could be used against anyone on the plane or anywhere else for that matter makes it through security. Size restrictions are more focused on limiting the amount of weight the plane carries and not overloading it.
TSA Carry-on Restrictions – There are carry on restrictions on basically every weapon, knife or gun, anything flammable, sports equipment, large tools, saws, drills, all martial arts weapons, any and all explosives, any chemicals, and most gels. The item by item list is much longer and can be found on the TSA website. In essence anything that can be seen as a threat or could harm a person, as well as anything that could cause problems with the plane.
Exceptions: There are exceptions for certain items. Weapons that are declared to the airline before getting aboard can often be carried provided they are locked using a safety mechanism, unloaded, and the person carrying them has no law violations. They can still be refused if the TSA finds apt reason.
Size Restrictions – Carry on size restrictions depend more on the airline then the TSA. Each model of plane has only a limited amount of space for carry on baggage as well as a limit to how much added weight they can take. For the most part the size limit for carry on luggage on all airlines is generally the same, 22” x 14” x 9” for luggage. Other bags like purses and computer bags are also allowed and they have their own size limits. There are also weight limits to each of these bags, though the size limits generally preclude ever surpassing that weight limit.
Note: Some airlines also limit the number of carry on bags that a person can carry on so it might be best to just pay the fee for one checked bag and not worry about it. Most airlines have begun or are planning to begin charging for carrying on baggage as well.