I truly do not understand why people don't simply wait until the kid is old enough to handle frying before travelling with an airplane. My family travelled a lot by train, or sometimes car, then when I was around 7 or 8 years old we took a short flight.
Babies really won't remember anything of the trip anyway, I really feel that travelling by plane is one of the things that you sacrifice for the first years of having a child. Call me entitled or whatever, but your childs screaming or running around on the plane is absolutely annoying to others.