If you look on Trip Advisor you'll see a variety of different behaviors, and few of them consistent. Lately, security at airports in Australia have been confiscating drones. I've read similar stories about a single airport in Vietnam. The most frequent advice I've seen is to pack the drone itself very well padded in your checked suitcase, and the batteries and RC in your carry-on. Keeping the aircraft separate from the batteries seems to stop confiscations, at least on international flights and going through customs. But it's a risk -- if you can't bear the thought of possibly losing it, leave it at home.