AIM ¶ 4-2-6 — Ground Station Call Signs
AIM 4-2-6 explains how pilots should address ATC ground stations: facility name plus type (Tower, Ground, Approach, Center, Radio, UNICOM).
In Plain English
When calling any ground facility on the radio, start with the facility name followed by the facility type. This standardization helps controllers immediately recognize who is being called and reduces frequency confusion.
Per AIM 4-2-6 (TBL 4-2-1), use these conventions:
- Airport UNICOM: "Shannon UNICOM"
- FAA Flight Service Station: "Chicago Radio"
- Airport Traffic Control Tower: "Augusta Tower"
- Clearance Delivery (IFR): "Dallas Clearance Delivery"
- Ground Control (in Tower): "Miami Ground"
- Radar or Nonradar Approach Control: "Oklahoma City Approach"
- Radar Departure Control: "St. Louis Departure"
- FAA Air Route Traffic Control Center (ARTCC): "Washington Center"
Note that Flight Service Stations are addressed as "Radio", not "Flight Service", and ARTCCs are addressed as "Center". Using the correct call sign on first contact is a recommended practice for clear, professional communications and is something examiners listen for during checkride radio work.
AIM Source Text
FAA AIM ¶ 4-2-64-2-6. 4-2-6. Ground Station Call Signs
Pilots, when calling a ground station, should begin with the name of the facility being called followed by the type of the facility being called as indicated in TBL 4-2-1 . TBL 4-2-1 Calling a Ground Station Facility Call Sign Airport UNICOM “Shannon UNICOM” FAA Flight Service Station “Chicago Radio” Airport Traffic Control Tower “Augusta Tower” Clearance Delivery Position (IFR) “Dallas Clearance Delivery” Ground Control Position in Tower “Miami Ground” Radar or Nonradar Approach Control Position “Oklahoma City Approach” Radar Departure Control Position “St. Louis Departure” FAA Air Route Traffic Control Center “Washington Center”
Oral Exam Questions a DPE Might Ask
Q1How should a pilot address a Flight Service Station on the radio?
Per AIM 4-2-6, a Flight Service Station is addressed using the facility name followed by the word "Radio," for example "Chicago Radio."
Q2What is the correct call sign for an ARTCC, and how does it differ from approach or tower?
Per AIM 4-2-6, an FAA Air Route Traffic Control Center is called using the facility name plus "Center" (e.g., "Washington Center"), whereas approach control uses "Approach" (e.g., "Oklahoma City Approach") and a tower uses "Tower" (e.g., "Augusta Tower").
Q3When initiating contact with any ground station, what general format should a pilot use?
Per AIM 4-2-6, the pilot should begin the call with the name of the facility followed by the type of facility, as listed in TBL 4-2-1 (for example, "Miami Ground" or "Dallas Clearance Delivery").
Related Paragraphs in AIM Chapter 4