If one controller manages both Arrival and Departure, what is the call sign they use?

When one controller is responsible for managing both arrivals and departures at an airport, they typically use the call sign "TERMINAL." This designation indicates that the controller oversees operations within the terminal airspace, which includes aircraft that are approaching to land and those that are taking off.

The use of the "TERMINAL" call sign helps to signify to pilots and other air traffic control personnel that this controller is handling the critical phases of flight near the airport, as well as coordinating the safe and efficient flow of traffic in and out of the terminal area. It establishes clarity in communication and ensures that all parties understand the scope of the controller's responsibilities.

In contrast, other call signs such as "RADIO," "GROUND," and "APRON" refer to different operational roles. "RADIO" typically relates to general communications and may not specify any particular control function. "GROUND" is used for controllers managing vehicles and aircraft movement on the taxiways and ramps, while "APRON" pertains to the area where aircraft are parked, loaded, or serviced but doesn't include management of air traffic. Hence, "TERMINAL" is the most appropriate and specific call sign for a controller managing both arrivals and departures.