Pilot Counsel

Two-way radio communications

July 1, 2010

John YodiceConflicts between pilots and controllers in what should be routine air traffic situations tell us that this is a legal concern that pilots might appreciate reviewing. In several places in the flight rules of FAR Part 91, in several forms, there is the requirement to “establish two-way radio communications with ATC.” This requirement frequently applies prior to entering certain airspace, and makes these situations time-critical.

Conflicts arise because what constitutes the “establishment” of the required communications can be subject to dispute. According to the FAA, not every response by ATC to a pilot call-up establishes two-way radio communications. The flight rules themselves are not helpful on this issue. However, the Aeronautical Information Manual, while technically not regulatory, does provide helpful guidance. According to the AIM, the key to whether communications have been established depends on the controller’s response to the pilot’s callup. If the controller responds using the aircraft’s call sign, communications have been established. If the controller responds to the initial radio call without using the aircraft identification, radio communications have not been established. This guidance can be helpful in keeping pilots out of trouble.

Here are some illustrations from the AIM. The conflicts often involve Class C, D, and E airspace.

Class C airspace is charted on Sectional and IFR En Route Low Altitude Charts for easy reference, and includes that airspace from the surface to 4,000 feet above the airport elevation (expressed in mean sea level) surrounding certain airports that have an operational control tower, radar approach control services, and certain minimum traffic and passenger counts. Here is the rule for aircraft arriving into or flying through Class C airspace: “Each person operating an aircraft in Class C airspace must establish two-way radio communications with the ATC facility providing air traffic services prior to entering that airspace and thereafter maintain those communications while within that airspace.” The same applies to departing flights, whether departing from the primary airport or a satellite airport with an operating control tower, except that an aircraft departing a satellite airport without an operating control tower must establish communications “as soon as practicable after departing.”

Here are illustrations from the AIM that show how the presence or absence of the magic words, the aircraft’s call sign, in the controller’s response have a significant legal effect:

  1. If the controller responds to a radio call with, “[aircraft call sign] stand by,” radio communications have been established.
  2. If workload or traffic conditions prevent immediate provision of Class C services, the controller will inform the pilot to remain outside the Class C airspace until conditions permit the services to be provided.
  3. It is important to understand that if the controller responds to the initial radio call without using the aircraft identification, radio communications have not been established and the pilot may not enter the Class C airspace. Example, “aircraft calling New York approach control, stand by.”

Communications for operations into Class D airspace have virtually the same legal situation. Class D airspace is also charted, and comprises the airspace from the surface to 2,500 feet above the airport elevation (charted in mean sea level) surrounding those airports that have an operational control tower but do not meet the Class C criteria. For aircraft operating at the primary airport, or departing a satellite airport that has an operating control tower, the pilot must “establish and maintain two-way radio communications with the ATC facility providing air traffic services prior to entering that airspace and thereafter maintain those communications while within that airspace.” Aircraft departing a satellite airport without an operating control tower must establish communications as soon as practicable.

Here is a helpful Class D illustration from the AIM: “If the controller responds to a radio call with, “[aircraft call sign] stand by,” radio communications have been established and the pilot can enter Class D airspace. It is important to understand that if the controller responds to the initial radio call without using the aircraft call sign, radio communications have not been established and the pilot may not enter the Class D airspace.” Example: “Aircraft calling Manassas Tower, stand by.”

Last, there are some airports with operating control towers that are in Class E airspace. An aircraft may not be operated to, from, through, or on an airport in Class E airspace that has an operational control tower “unless two-way radio communications are maintained between that aircraft and the control tower. Communications must be established prior to 4 nautical miles from the airport, up to and including 2,500 feet agl.”

So, as in Class E airspace and wherever there is a regulatory requirement to “establish two-way radio communications with ATC,” we should use the guidance provided by the AIM. That is, we should not consider that communications with ATC have been established as required unless the response to our call uses our aircraft’s identification. Then, pilots and controllers will better understand each other. Safety will be enhanced. And the possibility of FAA enforcement action will be significantly reduced.

John S. Yodice is the owner of a Cessna 310 based at Frederick, Maryland.