When I traveled to Lake Tahoe with, at the time, my 15 month old son, we carried our covertible car seat through the airport. It was a total pain but I'm glad we did. Since we had a seat for him, we just secured the car seat into his seat and he pretty much slept in the car seat like he would when we drive. Much better than holding him and knowing that he would be fussy and trying to run around. I think we plan to buy that luggage system where you can secure the car seat to wheels this year when we fly to San Diego, except this time I will have 2 car seats to think about. First, did you purchase a seat for your daughter? If you did not, you can't take the car seat into the plane and will have to check it in obviously. If you bring your convertible check it in curbside so it won't be a total pain to carry through the airport. But if she sleeps in her car seat like my son does it will be nice to have on the plane since more than likely she will sleep for most of the flight. For us, it was worth every cent having bought a seat for him and having him sleep through the flight.