Wondering if this list of items was permitted on a plane, specifically leaving O'Hare Airport if anyone has ever flown from here:
Jetboil Fuel Canister
Ursack Bear Bag
Any other miscellaneous backpacking items useful in the outdoors.
Any info would be greatly appreciated.
It depends on the size of your filled backpack and whether you want to take stuff that you have to check.
If you have to check stuff anyway (eg...tent poles trekking poles pointy things) then I would check it all packed carefully in your pack and inside a duffle or similar bag. If your pack has a rigid belt that could get crushed then you will want to pad it out say with your sleeping bag.
If you can get your pack to carry on size then you may prefer to just check the things you have to and carry on your pack. Bear in mind you will need to pack the same stuff for the return trip so you will need a way to recreate your packing...which you probably don't want to carry on your trip.
Within the US, you possibly could mail your self all your non carry on stuff for general delivery at a post office close to your destination. In theory you can mail butane gas canisters this way so long as the packages are properly marked. They have to go ground. This also might be a way to deal with "luggage" to pack your gear on your return trip particularly if you mail it to the same post office...I think you can do that. The downside is you have to get to the post office and often they open limited hours and are not open on weekends. Some outfitters, hotels and hostels will hold stuff you mail to them usually for a fee.
I'll second this. Every time I've taken a backpacking trip that required flights, I used the REI bag that is designed to hold your pack for flying (similar to a large duffle). Its tough, and keeps all the strap together and out of the way, and is certainly big enough for larger packs. This will save your pack from the hands of the TSA.