It depends on what you mean. You can transport some weapons such as handguns, shotguns, and knives in your checked, locked luggage, but you are not allowed to carry these items on your person or in your carry on luggage. To transport a firearm, you tell the ticket agent that you want to check an unloaded firearm. They will give you an orange tag that you sign and then that tags goes into your luggage.
No you need a Federal ID such as drivers license, passport or militay ID.
I can't see why you wouldn't be allowed to unless you conceal anything illegal in them.
Sure they can. Just go to your local Immigration office. They'll put you on a plane straight away.
nope because it can now be used as an offensive weapon to hiijac a plane
Yes, your horse can travel by plane to a competition. I asume that is very expensive!
airline travel is traveling on a plane
Travel by plane.
You can travel by plane.
Statistically plane travel is safer.
By plane,
a plane
There is no such age actually but for your own sake you need to be mature. But as per the rules, if you are not adult then, you can travel plane with escort. For that, you need to go through the proper channel.