followers the common traffic advisory frequency.

Standing advisory committee on radio frequency alocation.

An En Route Flight Advisory Service is a branch of the FAA. it is composed of men and women trained in weather reporting, traffic, and other factors having to do with flights between airports.

Automatic terminal advisory frequency.

The most effective frequency at a specified time for ionosperic propagation of radio waves between two specified points: also known as Frequency Optimum Traffic; Optimum Traffic Frequency