Not having the information if the airline requests it could result in missing your flight. Make sure Baby is sucking on a bottle or pacifier during the take-off and landing. This will help prevent painful ear pressure. Since airplane cabins are being pressurized before take-off, a pacifier or bottle should help with any ear pain baby experiences during this time as well. The flight attendant should be happy to keep extra bottles in the plane's refrigerator for you, as well as warm bottles as Baby needs them.
Babies spit up, and diapers sometimes leak.
Consider having at least one change of clothes for Mom, Dad, and Baby in the diaper bag, depending on the length of your flight. This will also be comforting to Baby and keep your hands fairly free during the flight. Even though we adopted from another state, we chose to drive instead of fly. We had a luncheon scheduled with Baby's birth mother a few days after placement, so we remained in the agency's town until after our visit. Then we drove to within a few miles of the state line, headed home.