Definition
A radio frequency assigned to a specific airport for pilots to broadcast their position and intentions when operating at that airport without an active control tower. Pilots use this single shared frequency to self-coordinate arrivals, departures, and ground movement by announcing their location and intentions to other traffic in the area.
Plain English
A radio channel set aside for one airport so pilots flying in or out can talk to each other and stay clear of one another when no controller is on duty.
Context Anchor
Seen in airport information, charts, and the Chart Supplement when preparing to arrive at or depart from a non-towered airport.
Derivation
‘Common’ here means shared by everyone using that airport. ‘Advisory’ signals that pilots are giving and receiving information to help one another, not receiving instructions from a controller. The word ‘designated’ means the frequency has been formally assigned to that airport for this purpose.
Why Pilots Care
Using the correct frequency lets pilots know where other aircraft are and reduces the chance of conflicts in the traffic pattern.
Intuition Check
Do not read “common” as meaning any frequency that many pilots happen to use. Here, the key word is “designated”: it means the assigned, published frequency for that airport.
Example Sentence 1
Ten miles out, the pilot tuned the designated common traffic advisory frequency for the destination airport and listened for other traffic before making a position call.
Example Sentence 2
The sectional chart showed the designated common traffic advisory frequency as 122.8, so the pilot monitored it for traffic calls while taxiing.