Eventually this will be handled by the proficiency system, but in the short term, there should be different traits to enable different vehicles. So TRAINED_ROTORCRAFT_PILOT would let you fly helicopters, TRAINED_FIXEDWING_PILOT would let you fly normal planes, etc.
Piloting as a general skill to represent your ability to navigate and control any flying vehicle works fine, with proficiencies/traits to cover the stuff you really know.