Yes I have flown with the PC many times now. It just about fits into the peli air 1535, and that is of allowable size for carry on. I have not run into any issues regarding the liquid cooling. Every single time security makes me open the peli case and asks what it is, but then let me through. HOWEVER, once (in germany) I was asked to weigh the case, and it came in at 13Kg, which is above the standard limit of 8Kg for carry ons. They did not want to let me take it on, ordering that I check the case in - which I adamently refused (since the protection in the pelicase is rather thin and weak). I argued all the way to the highest level, getting managers etc involved, and was allowed to take the case onboard - not putting it in the overhead storage, but it was taken onboard into a separate private area (I believe where the crew store their bags). I believe this was a favour they did to me that I will not be able to pull again. So I'm really hesitant to fly with it again unfortunately due to the weight.