I have flown with my now 2 1/2 month son a LOT since he was 8 weeks old. First off, I would suggest bringing your carseat. If there is room on the flight, they will actually let you bring it on and get an extra seat. All the times I'd flown with my son, I brought our whole travel system (carseat/stroller). When he grew out of the carseat, I still brought the stroller along, and his separate carseat. It actually worked where I just set his carseat down into the stroller, and it worked fine. They gate check the stroller...and the carseat if there's no room on the flight for it. I never had any problems while flying with him, AND, because a lot of times I flew by myself with him, the stewardesses were always extra helpful, and the pilot even carried some of our stuff on the plane for us one time (that was when I flew with my then 19 month old son AND my then-10 year old step-daughters ALONE).