Definition
A radio frequency designated for pilots to broadcast their position and intentions to other aircraft when operating at an airport without an active control tower. The CTAF may be a UNICOM, MULTICOM, FSS, or tower frequency, and is identified on aeronautical charts and in the Chart Supplement.
Plain English
A shared radio frequency that pilots use to talk to each other at airports where no one in a tower is directing traffic. Everyone tunes to the same frequency and announces what they are doing so other pilots in the area know where they are.
Context Anchor
Pilots see the CTAF listed in airport information and use it before taxi, takeoff, landing, or flying near that airport.
Derivation
Common because everyone shares it. Traffic Advisory because pilots use it to advise other traffic of their position and intentions. Frequency because it is a specific radio channel.
Why Pilots Care
Lets pilots coordinate their movements and maintain separation without ATC assistance, directly reducing the chance of conflicts in the airport traffic area.
Intuition Check
A CTAF is not a control frequency, and a call on CTAF is not a clearance. It is a shared frequency for pilots to coordinate with each other.
Example Sentence 1
Ten miles out, she switched to the CTAF and announced her position and intention to enter a left downwind for runway 27.
Example Sentence 2
All aircraft operating in the area monitor the CTAF so they remain aware of other traffic in the pattern.