Hi, I have three kids and we have traveled with them at all different ages. Here are my observations on what to do/use to make a good trip with a baby:
1) Stroller: Check it in at the airplane door, or if you are flying an airline that won't let you do that, consider a travel stroller like the one by summer infant. It folds into three and is super light. It fits into the overhead compartment on the plane so you don't have to check it in at the check in counter (
http://www.summerinfant.com/strollers.htm and you can buy them at
www.target.com).
2) Feeding: Try to arrange it so that it's bottle time when the plane takes off, to help with little ears. If the baby fusses a bit and the plane isn't taking off yet, try to keep her as satisfied as possible to wait until take off. It's better people on the plane with you have to deal with a little noise beforehand because if her ears start popping it can be unpleasant and she might wind up for a big cry. But of course you know your baby's moods best.
3) Napping: I have had 50% success with bassinet usage. You should end up with a bulkhead seat, which is nice to be able to stretch your legs in front of you in case you aren't able to get up and walk around because you are holding a sleeping baby.
4) Diaper changing: Slather a bunch of desitin or balmex on her bottom so that diaper changing goes easier, or if she sleeps the majority of the plane trip you aren't worrying that she will get a diaper rash.
5) Entertainment: Buy some new toys/stickers/biter biscuits to pull out for playing.
6) If she cries: Don't be too apologetic to those around you. I would try to avoid too much eye contact with people if it happens because then sometimes people feel they have the right to make comments to you, not all of them supportive. People will take their cue from you and pick up on your state of being. If you can project a sense of confidence, being calm and soothing with your baby it send the message to anyone watching you that they needn't worry, you have everything under control. I would venture a commiserating smile if you do end up making eye contact, but don't worry about other people too much. You can't please everyone.
Good luck, and have a safe trip!