CO2 are used a lot in triathlon also as you want the bike as area as you can Beerguts don't help) neither does a pump. The inflate a tyre in seconds and get them to such a high presssure that would break you arm or take 2 days with a mini pump

I think I may have forgotten them a couple of times in my bike bag. Calling Teece. I am sure Teece as he is a man who knows about flying with a bike