Traveling with a 600mm

I recently acquired a Canon 600mm lens. I was looking advice regarding transporting during air travel both domestically or internationally with these larger lens. I do have a Think Tank international, but this lens will not fit in this bag. I've looked at a few options that would allow me to transport the lens itself but not the rest of my gear etc. Any ideas, solutions (sending ahead of time etc) would be greatly appreciated.

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I use a Kinesis backpack to transport a 500 mm f/4 lens with TC and camera body attached, lens hood reversed. My regular carry-on bag goes in the overhead bin and the camera travels between my feet and as far under the seat in front of me as it can go. The camera satisfies the conditions of the allowed, second small carry-on item. My wife does the same, but with a smaller Kinesis bag with a second body and landscape lens. So far, we have had no issues with this system and have traveled domestically as well as in Central America.