Commission Implementing Regulation (EU) No 923/2012 of 26 September 2012 laying down the common rules of the air and operational provisions regarding services and procedures in air navigation and amending Implementing Regulation (EU) No 1035/2011 and Regulations (EC) No 1265/2007, (EC) No 1794/2006, (EC) No 730/2006, (EC) No 1033/2006 and (EU) No 255/2010 Text with EEA relevance

‘accuracy’ means a degree of conformance between the estimated or measured value and the true value;

‘advisory airspace’ means an airspace of defined dimensions, or designated route, within which air traffic advisory service is available;

‘advisory route’ means a designated route along which air traffic advisory service is available;

‘aerobatic flight’ means manoeuvres intentionally performed by an aircraft involving an abrupt change in its attitude, an abnormal attitude, or an abnormal variation in speed, not necessary for normal flight or for instruction for licenses or ratings other than aerobatic rating;

‘aerodrome’ means a defined area (including any buildings, installations and equipment) on land or water or on a fixed, fixed off-shore or floating structure intended to be used either wholly or in part for the arrival, departure and surface movement of aircraft;

‘aerodrome control service’ means air traffic control service for aerodrome traffic;

‘aerodrome control tower’ means a unit established to provide air traffic control service to aerodrome traffic;

‘aerodrome traffic’ means all traffic on the manoeuvring area of an aerodrome and all aircraft flying in the vicinity of an aerodrome. An aircraft operating in the vicinity of an aerodrome includes but is not limited to aircraft entering or leaving an aerodrome traffic circuit;

‘aerodrome traffic circuit’ means the specified path to be flown by aircraft operating in the vicinity of an aerodrome;

‘aerodrome traffic zone’ means an airspace of defined dimensions established around an aerodrome for the protection of aerodrome traffic;

‘aerial work’ means an aircraft operation in which an aircraft is used for specialised services such as agriculture, construction, photography, surveying, observation and patrol, search and rescue, aerial advertisement, etc.;

‘Aeronautical Information Publication (AIP)’ means 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’ means 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’ means 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;

‘aeroplane’ means a power-driven heavier-than-air aircraft, deriving its lift in flight chiefly from aerodynamic reactions on surfaces which remain fixed under given conditions of flight;

‘airborne collision avoidance system (ACAS)’ means 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’ means 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’ means a unique combination of 24 bits available for assignment to an aircraft for the purpose of air-ground communications, navigation and surveillance;

‘aircraft observation’ means the evaluation of one or more meteorological elements made from an aircraft in flight;

‘AIRMET’ means 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 of the development of those phenomena in time and space, and which was not already included in the forecast issued for low-level flights in the flight information region concerned or sub-area thereof;

‘air-ground communication’ means two-way communication between aircraft and stations or locations on the surface of the earth;

‘air-ground control radio station’ means an aeronautical telecommunication station having primary responsibility for handling communications pertaining to the operation and control of aircraft in a given area;

‘air-report’ means a report from an aircraft in flight prepared in conformity with requirements for position, and operational and/or meteorological reporting;

‘air-taxiing’ means movement of a helicopter/vertical take-off and landing (VTOL) above the surface of an aerodrome, normally in ground effect and at a ground speed normally less than 37 km/h (20 kts);

‘air traffic’ means all aircraft in flight or operating on the manoeuvring area of an aerodrome;

‘air traffic advisory service’ means a service provided within advisory airspace to ensure separation, in so far as practical, between aircraft which are operating on instrument flight rules (IFR) flight plans;

‘air traffic control (ATC) clearance’ means authorisation for an aircraft to proceed under conditions specified by an air traffic control unit;

‘air traffic control instruction’ means directives issued by air traffic control for the purpose of requiring a pilot to take a specific action;

‘air traffic control service’ means a service provided for the purpose of:

‘air traffic control unit’ means a generic term meaning variously, area control centre, approach control unit or aerodrome control tower;

‘air traffic service (ATS)’ means a generic term meaning variously, flight information service, alerting service, air traffic advisory service, air traffic control service (area control service, approach control service or aerodrome control service);

‘air traffic services (ATS) airspaces’ mean airspaces of defined dimensions, alphabetically designated, within which specific types of flights may operate and for which air traffic services and rules of operation are specified;

‘air traffic services (ATS) reporting office (ARO)’ means a unit established for the purpose of receiving reports concerning air traffic services and flight plans submitted before departure;

‘air traffic services (ATS) unit’ means a generic term meaning, variously, air traffic control unit, flight information centre, aerodrome flight information service unit or air traffic services reporting office;

‘airway’ means a control area or portion thereof established in the form of a corridor;

‘alerting service’ means a service provided to notify appropriate organisations regarding aircraft in need of search and rescue aid, and assist such organisations as required;

‘alternate aerodrome’ means an aerodrome to which an aircraft may proceed when it becomes either impossible or inadvisable to proceed to or to land at the aerodrome of intended landing, where the necessary services and facilities are available, where aircraft performance requirements can be met and which is operational at the expected time of use. Alternate aerodromes include the following:

‘altitude’ means the vertical distance of a level, a point or an object considered as a point, measured from mean sea level (MSL);

‘approach control service’ means air traffic control service for arriving or departing controlled flights;

‘approach control unit’ means a unit established to provide air traffic control service to controlled flights arriving at, or departing from, one or more aerodromes;

‘apron’ means a defined area, intended to accommodate aircraft for purposes of loading or unloading passengers, mail or cargo, fuelling, parking or maintenance;

‘area control centre (ACC)’ means a unit established to provide air traffic control service to controlled flights in control areas under its jurisdiction;

‘area control service’ means air traffic control service for controlled flights in control areas;

‘area navigation (RNAV)’ means a method of navigation which permits aircraft operation on any desired flight path within the coverage of ground- or space-based navigation aids or within the limits of the capability of self-contained aids, or a combination of these;

‘ATS route’ means a specified route designed for channelling the flow of traffic as necessary for the provision of air traffic services;

‘automatic dependent surveillance — broadcast (ADS-B)’ means a means by which aircraft, aerodrome vehicles and other objects can automatically transmit and/or receive data such as identification, position and additional data, as appropriate, in a broadcast mode via a data link;

‘automatic dependent surveillance — contract (ADS-C)’ means a means by which the terms of an ADS-C agreement will be exchanged between the ground system and the aircraft, via a data link, specifying under what conditions ADS-C reports would be initiated, and what data would be contained in the reports;

‘automatic terminal information service (ATIS)’ means the automatic provision of current, routine information to arriving and departing aircraft throughout 24 hours or a specified portion thereof:

‘ceiling’ means the height above the ground or water of the base of the lowest layer of cloud below 6 000 m (20 000 ft) covering more than half the sky;

‘change-over point’ means the point at which an aircraft navigating on an ATS route segment defined by reference to very high frequency omnidirectional radio ranges is expected to transfer its primary navigational reference from the facility behind the aircraft to the next facility ahead of the aircraft;

‘clearance limit’ means the point to which an aircraft is granted an air traffic control clearance;

‘cloud of operational significance’ means a cloud with the height of cloud base below 1 500 m (5 000 ft) or below the highest minimum sector altitude, whichever is greater, or a cumulonimbus cloud or a towering cumulus cloud at any height;

‘code (SSR)’ means the number assigned to a particular multiple pulse reply signal transmitted by a transponder in Mode A or Mode C;

‘competent authority’ means the authority designated by the Member State as competent to ensure compliance with the requirements of this Regulation;

‘control area’ means a controlled airspace extending upwards from a specified limit above the earth;

‘controlled aerodrome’ means an aerodrome at which air traffic control service is provided to aerodrome traffic;

‘controlled airspace’ means an airspace of defined dimensions within which air traffic control service is provided in accordance with the airspace classification;

‘controlled flight’ means any flight which is subject to an air traffic control clearance;

‘controller-pilot data link communications (CPDLC)’ mean a means of communication between controller and pilot, using data link for ATC communications;

‘control zone’ means a controlled airspace extending upwards from the surface of the earth to a specified upper limit;

‘cruise climb’ means an aeroplane cruising technique resulting in a net increase in altitude as the aeroplane mass decreases;

‘cruising level’ means a level maintained during a significant portion of a flight;

‘current flight plan (CPL)’ means the flight plan, including changes, if any, brought about by subsequent clearances;