Definition
Initial radio contact made by one station to another to establish communication, in which the calling station identifies the station being called and then identifies itself.
Plain English
The first radio call you make to get someone's attention before passing your message. You say who you are calling, then who you are.
Context Anchor
Used during aircraft radio communications, especially when first contacting ground control, tower, approach control, or flight service.
Derivation
Call comes from an older word meaning to speak out or summon someone. In aviation radio use, a call-up is the act of calling a station so communication can begin.
Why Pilots Care
A clear call-up ensures the receiving station is listening before you transmit important details such as position, altitude, or requests.
Intuition Check
Call-up does not mean a phone call or a military summons here. In aviation, it means the first radio contact used to start communication.
Example Sentence 1
She made the call-up with "Centennial Tower, Cessna Three-Four-Alpha," and waited for the controller to respond before passing her request.
Example Sentence 2
After the call-up the controller responded and the pilot requested vectors to the airport.