What does the "C" after an airport frequency signify?

The "C" after an airport frequency indicates that it is a Common Traffic Advisory Frequency (CTAF). This frequency is designated for pilots to use when operating in non-towered airports or when communicating with other traffic in the vicinity of an airport. The purpose of using a CTAF is to enhance safety by allowing pilots to announce their intentions and positions to one another, ensuring better situational awareness among all users of the airspace in that area.

Using a CTAF helps create a common platform for communication, especially in environments where there is no control tower to manage the traffic. Pilots utilize this frequency to announce their approaches, departures, and other maneuvers, fostering an open line of communication that is essential for maintaining safety in the airspace around an airport.