I have never been able to install a graco carseat with base on a plane. However, I have successfully installed them without the base. Just makes it a bit of a pain to get the baby in and out (you have to either loosen or undo the seatbelt each time).
The person in front of you won't be able to recline, Ive only had a problem with one person on that. Funny thing is she was flying with three kids, all in carseats but wanted to complain to the flight attendant that my carseat was blocking her recline and I needed to move.