Common Traffic Advisory Frequency
Encyclopedia
Common Traffic Advisory Frequency (CTAF), is the name given to the VHF radio frequency
used for air-to-air communication at U.S.
, Canadian
and Australia
n non-towered airport
s.
Many towered airports close their towers overnight, keeping the airport itself open for cargo operations and other activity. Pilot
s use the common frequency to coordinate their arrivals and departures safely, giving position reports and acknowledging other aircraft in the airfield traffic pattern
.
In many locations, smaller airports use pilot-controlled lighting systems
when it is uneconomical or inconvenient to have automated systems or staff to turn on the taxiway
and runway lights. In Canada, the lighting system is accessed through an Aircraft Radio Control of Aerodrome Lighting
(ARCAL) frequency which is often shared with the CTAF.
Two common CTAF allocations are UNICOM
, a licensed non-government base station that provides air-to-ground communications (and vice versa) and may also serve as a CTAF when in operation, and MULTICOM
, a frequency allocation (without a physical base station) that is reserved as a CTAF for airports without other facilities.
US/World
One important note to all aviators: UNICOM and a CTAF are mutually exclusive. This distinction led to nearly disastrous consequences during hurricane Katrina as pilots flying into unfamiliar airports did not properly interpret their sectional map and communicated on the wrong frequency. UNICOM airports never have an operating control tower.
Radio frequency
Radio frequency is a rate of oscillation in the range of about 3 kHz to 300 GHz, which corresponds to the frequency of radio waves, and the alternating currents which carry radio signals...
used for air-to-air communication at U.S.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, Canadian
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
and Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
n non-towered airport
Non-towered airport
A non-towered airport, sometimes referred to as an uncontrolled airport, is an airport with no operating tower, or air traffic control unit...
s.
Many towered airports close their towers overnight, keeping the airport itself open for cargo operations and other activity. Pilot
Aviator
An aviator is a person who flies an aircraft. The first recorded use of the term was in 1887, as a variation of 'aviation', from the Latin avis , coined in 1863 by G. de la Landelle in Aviation Ou Navigation Aérienne...
s use the common frequency to coordinate their arrivals and departures safely, giving position reports and acknowledging other aircraft in the airfield traffic pattern
Airfield traffic pattern
An airfield traffic pattern is a standard path followed by aircraft when taking off or landing, while maintaining visual contact with the airfield....
.
In many locations, smaller airports use pilot-controlled lighting systems
Pilot Controlled Lighting
Pilot Controlled Lighting , also known as Aircraft Radio Control of Aerodrome Lighting or Pilot Activated Lighting , is a system which allows aircraft pilots to control the lighting of an airport or airfield's approach lights, runway edge lights, and taxiways via radio. At some airfields, the...
when it is uneconomical or inconvenient to have automated systems or staff to turn on the taxiway
Taxiway
A taxiway is a path on an airport connecting runways with ramps, hangars, terminals and other facilities. They mostly have hard surface such as asphalt or concrete, although smaller airports sometimes use gravel or grass....
and runway lights. In Canada, the lighting system is accessed through an Aircraft Radio Control of Aerodrome Lighting
Pilot Controlled Lighting
Pilot Controlled Lighting , also known as Aircraft Radio Control of Aerodrome Lighting or Pilot Activated Lighting , is a system which allows aircraft pilots to control the lighting of an airport or airfield's approach lights, runway edge lights, and taxiways via radio. At some airfields, the...
(ARCAL) frequency which is often shared with the CTAF.
Two common CTAF allocations are UNICOM
UNICOM
Universal Communications or as known by its abbreviation, UNICOM, is an air-ground communication facility operated by a private agency to provide advisory service at uncontrolled aerodromes and airports.-Description:...
, a licensed non-government base station that provides air-to-ground communications (and vice versa) and may also serve as a CTAF when in operation, and MULTICOM
MULTICOM
In U.S. and Canadian aviation, MULTICOM is a frequency allocation used as a Common Traffic Advisory Frequency by aircraft near airports where no air traffic control is available...
, a frequency allocation (without a physical base station) that is reserved as a CTAF for airports without other facilities.
Australia
In Australia, there are many landing strips in remote locations that have CTAF operations 24 hours a day, seven days a week. There are also CTAF(R) landing strips which require the aircraft intending to enter the area of operation to be fitted with a radio. The most common CTAF frequency is 126.7 at non towered aerodromes except for when two CTAF airports are near each other. Aerodromes using CTAF outside tower hours typically nominate a frequency that is used during tower hours.US/World
One important note to all aviators: UNICOM and a CTAF are mutually exclusive. This distinction led to nearly disastrous consequences during hurricane Katrina as pilots flying into unfamiliar airports did not properly interpret their sectional map and communicated on the wrong frequency. UNICOM airports never have an operating control tower.