Aviation Definitions

Advisory airspace. An airspace of defined dimensions, or designated route, within which air traffic advisory service is available.
Advisory route. A designated route along which air traffic advisory service is available.
Aerodrome. A defined area on land or water (including any buildings, installations and equipment) intended to be used either wholly or in part for the arrival, departure and surface movement of aircraft.
Aerodrome control service. Air traffic control service for aerodrome traffic.
Aerodrome control tower. A unit established to provide air traffic control service to aerodrome traffic.
Aerodrome elevation. The elevation of the highest point of the landing area.
Aerodrome traffic. All traffic on the manoeuvring area of an aerodrome and all aircraft flying in the vicinity of an aerodrome.
Aerodrome traffic circuit. The specified path to be flown by aircraft operating in the vicinity of an aerodrome.
Aeronautical fixed service (AFS). A telecommunication service between specified fixed points provided primarily for the safety of air navigation and for the regular, efficient and economical operation of air services.
Aeronautical fixed station. A station in the aeronautical fixed service.
Aeronautical ground light. Any light specially provided as an aid to air navigation, other than a light displayed on an aircraft.
Aeronautical Information Publication (AIP). A publication issued by or with the authority of a State and containing aeronautical information of a lasting character essential to air navigation.
Aeronautical mobile service. A mobile service between aeronautical stations and aircraft stations, or between aircraft stations, in which survival craft stations may participate; emergency position-indicating radio beacon stations may also participate in this service on designated distress and emergency frequencies.
Aeronautical station. A land station in the aeronautical mobile service. In certain instances, an aeronautical station may be located, for example, on board ship or on a platform at sea.
Aeronautical telecommunication station. A station in the aeronautical telecommunication service.
Airborne collision avoidance system (ACAS). An aircraft system based on secondary surveillance radar (SSR) transponder signals which operates independently of ground-based equipment to provide advice to the pilot on potential conflicting aircraft that are equipped with SSR transponders.
Aircraft. Any machine that can derive support in the atmosphere from the reactions of the air other than the reactions of the air against the earth’s surface.
Aircraft address. A unique combination of 24 bits available for assignment to an aircraft for the purpose of air-ground communications, navigation and surveillance.
Aircraft identification. A group of letters, figures or a combination thereof which is either identical to, or the coded equivalent of, the aircraft call sign to be used in air-ground communications, and which is used to identify the aircraft in ground-ground air traffic services communications.
Aircraft observation. The evaluation of one or more meteorological elements made from an aircraft in flight.
Air-ground communication. Two-way communication between aircraft and stations or locations on the surface of the earth.
AIRMET information. Information issued by a meteorological watch office concerning the occurrence or expected occurrence of specified en-route weather phenomena which may affect the safety of low-level aircraft operations and which was not already included in the forecast issued for low-level flights in the flight information region concerned or sub-area thereof.
AIRPROX. The code word used in an air traffic incident report to designate aircraft proximity.
Air-report. A report from an aircraft in flight prepared in conformity with requirements for position, and operational and/or meteorological reporting.
Air-taxiing. Movement of a helicopter/VTOL above the surface of an aerodrome, normally in ground effect and at a ground speed normally less than 37 km/h (20 kt).
Air-to-ground communication. One-way communication from aircraft to stations or locations on the surface of the earth.
Air traffic. All aircraft in flight or operating on the manoeuvring area of an aerodrome.
Air traffic advisory service. A service provided within advisory airspace to ensure separation, in so far as practical, between aircraft which are operating on IFR flight plans.
Air traffic control clearance. Authorization for an aircraft to proceed under conditions specified by an air traffic control unit.
Air traffic control instruction. Directives issued by air traffic control for the purpose of requiring a pilot to take a specific action.
Air traffic control service. A service provided for the purpose of:
a) preventing collisions:
1) between aircraft, and
2) on the manoeuvring area between aircraft and obstructions; and
b) expediting and maintaining an orderly flow of air traffic.
Air traffic control unit. A generic term meaning variously, area control centre, approach control unit or aerodrome control tower.

About Wayne Farley

I am Wayne, a career air traffic controller. Engage me while I share my thoughts, experience, and news from around the aviation world. A post titled “13 Characteristics of an Air Traffic Controller” written in 2010 went viral and established me as the unofficial ambassador of ATC.

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