I haven't flown with it but I'm pretty sure it's not carry-on size when folded. If that was what you were looking for. It would have to be a sizable suitcase to fit the bike in, they sell a soft bag for it but I wouldn't trust the baggage handlers not to damage the bike (worked for TWA back in the day loading the planes).

Here's a pic of it folded to get an idea. The seat post will go down more and just FYI the front wheel is removed to fold.