Restrictions for Checked Luggage
After considering all the confusing and heavy-handed restrictions placed on items permitted in carry-on luggage, you might be surprised at the wide range of things you're permitted to stash in your checked bags. There are only a few broad restrictions on checked luggage, almost all having to do with safety concerns. Individual airlines may also have regulations regarding bag weight and size in addition to specific procedures in place for live animals, sports equipment and other special cases. Note that, if you are flying internationally, there may be additional customs restrictions. For the most comprehensive and up-to-date list of banned hazardous materials, check the Federal Aviation Administration's Web site.
Flammables and Explosives
The reason for forbidding flammable substances and explosives on airplanes should be obvious -- you don't want something catching on fire or punching a hole in the luggage compartment while your plane's in the air. That means no flares, no fireworks, no dynamite. Flammable paint, gasoline, cooking fuels and turpentine are banned as well. It also means no matches and no cigarette or torch lighters; you can carry personal lighters and matches in your carry-on instead. Guns are allowed in checked luggage but ammunition and gunpowder are not. Realistic replicas of all of the above are also disallowed.
Items consisting of compressed gas are also forbidden by the Transportation Security Administration and Federal Aviation Administration. Personal aerosol containers such as spray-on deodorant are allowed, but fire extinguishers, spray paint and tear gas -- including self-defense sprays -- are forbidden.
Certain corrosive chemicals are also banned from checked luggage. Bleach and chlorine for cleaning pools are the two notable examples in this category.
Size and Weight Restrictions
Size and weight restrictions regarding checked baggage vary from airline to airline. Generally you will be allowed a certain weight and size maximum, after which you will be charged extra fees for transport.