For an IFR general aviation flight, which callsign is typically used in air-ground communications?

• A. The aircraft's registration (N-number) or the filed flight identification
• B. The airline flight number
• C. The military callsign
• D. The weather station ID

Answer: (A)

When communicating with ATC, your callsign should be a fixed, recognizable identifier for the aircraft. For IFR general aviation in the United States, that is usually the aircraft’s registration number (the N-number) or, if you filed a specific flight identification in your flight plan, that flight identification. The registration provides a unique and constant identity for the plane, while the filed flight ID is used when a particular operator wants a different, easily recognized code. This helps ATC distinguish you from other traffic, track your position, and sequence you properly through airspace. Airline flight numbers are used for commercial airline operations, military callsigns for military flights, and weather station IDs are not used for identifying aircraft in air-ground radio communications.