A pilot will probably only perform one kind of mission, either CAS, AirDef, Strike, ASW, SAR etc. It depends on what aircraft you decide to use. If, for example, you chose an A-10 to be the character's aircraft you'd be limited to doing CAS or observation missions. I'd suggest picking CAS because they will be more flexible and varied than AirDef (fly around and blow stuff up) or Strike (fly to point A and blow stuff up) whereas CAS would be; fly to point A, find a target, destroy it, now divert to point B...