Alaska CTAFs are regional

Some areas in the state have high concentrations of airports, often a mixture of public and private facilities, ranging from busy residential airparks to farm strips. These areas often have high volumes of air traffic, but without the benefit of a control tower or airspace requiring two-way communication. 

In response to some tragic midair collisions, the FAA worked with aviation industry groups to develop the concept of using a common traffic advisory frequency to cover a geographic area, rather than an individual airport. The convention of a area-based CTAF is unique to Alaska and not routinely depicted on aeronautical charts—so how are pilots supposed to find out when they are entering a CTAF area not associated with an airport? The information is published in the Notices Section of the Alaska Chart Supplement, but recently Alaska Flight Service has posted a set of diagrams depicting these larger areas on its website in a single location. 

Background

CTAFs are defined for use while operating to and from nontowered airports—or airports where the control tower is not in operation. They provide a means to increase situational awareness among aircraft sharing the airspace and to help avoid midair collisions.  According to the Aeronautical Information Manual, pilots are expected to monitor and communicate on a CTAF within 10 miles of the airport they are operating to or from. 

Private airstrips are very popular in Alaska, where the lack of roads makes airplanes an essential means of transportation. The Matanuska Susitna Valley, in south central Alaska, has over 200 registered airports and landing areas. Initially, airports were assigned one or another of the CTAF frequencies allowed by FAA. However, this resulted in a situation where two aircraft, headed to nearby airstrips, could share the same airspace while monitoring different CTAFs—a detriment to safety.

Designated CTAF areas

To address this issue, FAA and an aviation industry working group went through a lengthy process to define discrete CTAF zones in selected locations, where all airstrips and landing areas are using the same frequency. Today, designated CTAF areas are found in several locations, where high volumes of traffic are known to operate, often without the benefit of radar coverage to provide VFR flight following. However, this solution isn’t perfect—on busy flying days, frequency congestion becomes a problem. Consequently, pilots need to be concise when reporting their location and intentions.