What kind of tripod?
I was flying Air New Zealand a couple of months ago and thought I'd ask at the check in desk before I got to security. My tripod has some pretty sharp metal spikes on the bottom so they said to check it with the main luggage. If you don't pack it into a suitcase with lots of clothes, ask them to put a fragile tag on it. It might still be thrown around but at least it's less likely to have 300kg of other people's suitcases on top.