A UNICOM (universal communications) station is an air-ground communication facility operated by a non-
air traffic control
Air traffic control (ATC) is a service provided by ground-based air traffic controllers who direct aircraft on the ground and through a given section of controlled airspace, and can provide advisory services to aircraft in non-controlled airsp ...
private agency to provide advisory service at
uncontrolled aerodromes and airports and to provide various non-flight services, such as requesting a
taxi
A taxi, also known as a taxicab or simply a cab, is a type of vehicle for hire with a driver, used by a single passenger or small group of passengers, often for a non-shared ride. A taxicab conveys passengers between locations of their choic ...
, even at towered airports.
It is also known as an ''aeronautical advisory station''. The equivalent European/ICAO service is known as ''(aerodrome) flight information service'', abbreviated as AFIS or FIS.
Description
UNICOM is employed at airports with a low volume of
general aviation
General aviation (GA) is defined by the International Civil Aviation Organization (ICAO) as all civil aviation aircraft operations with the exception of commercial air transport or aerial work, which is defined as specialized aviation services ...
traffic and where no
control tower
Air traffic control (ATC) is a service provided by ground-based air traffic controllers who direct aircraft on the ground and through a given section of controlled airspace, and can provide advisory services to aircraft in non-controlled air ...
is active. UNICOM stations typically use a single communications frequency. Some airfields always offer UNICOM service while others revert to UNICOM procedures only during hours when the control tower is closed. Under this protocol, aircraft may call a non-government ground station to make announcements of their intentions. Pilots who join the frequency later can request field advisories, which may include "weather information, wind direction, the recommended runway" and any previously reported traffic.
In some cases, the ground station is not staffed, and attempts to communicate will, of course, receive no acknowledgement. During these times, pilots self-announce their position and/or intentions over the
CTAF frequency, which is often the same as the UNICOM frequency. When a part-time UNICOM station is located on the same airport as a part-time control tower, the same frequency will be used by both ground stations to avoid confusion. Many UNICOM stations are operated by a
fixed-base operator
A fixed-base operator (FBO) is an organization granted the right by an airport to operate at the airport and provide aeronautical services such as fueling, hangaring, tie-down and parking, aircraft rental, aircraft maintenance, flight instructio ...
(FBO), and it may be possible to request services such as fuel trucks, taxi service from the airport, outgoing phone calls, and others.
''FBO at small airport using unassigned unicom frequency for airport information.''
NASA ASRS Report 106369, March 1989. 37000 Feet. August 2007. Retrieved 26 February 2013.
Frequencies
The actual frequency used at any particular airport can be found on the relevant sectional, terminal area chart or in airport directories, such as the Canada Flight Supplement
The Canada Flight Supplement (CFS) (french: link=no, Supplément de vol Canada) is a joint civil/military publication and is a supplement of the Aeronautical Information Publication (AIP Canada). It is the nation's official airport directory. It ...
.
United States
In the United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country Continental United States, primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., ...
, radio frequencies made available by the Federal Communications Commission
The Federal Communications Commission (FCC) is an independent agency of the United States federal government that regulates communications by radio, television, wire, satellite, and cable across the United States. The FCC maintains jurisdicti ...
for use as UNICOM are:
Canada
In Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by to ...
, the radio frequencies assigned for UNICOM are:
See also
* CTAF
* MULTICOM
References
* "Chapter 4: Air Traffic Control
Air traffic control (ATC) is a service provided by ground-based air traffic controllers who direct aircraft on the ground and through a given section of controlled airspace, and can provide advisory services to aircraft in non-controlled airsp ...
," ''Airman's Information Manual'' (Washington, DC
)
, image_skyline =
, image_caption = Clockwise from top left: the Washington Monument and Lincoln Memorial on the National Mall, United States Capitol, Logan Circle, Jefferson Memorial, White House, Adams Morg ...
: Superintendent of Documents, 1999).
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Airbands
Aviation communications