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see also: World Geodetic System 1984 (WGS-84)

Fr: Système de référence nord-américain de 1983
North American Route Other expression for: North American Routes System (NAR System)
. abbreviation: NAR
North American Routes System A special routing system consisting of routes located within the high level airspace established to facilitate control of the flow of international air traffic between the North Atlantic (NAT) and domestic airspace, as described in the “Planning” section of the Canada Flight Supplement (CFS).
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abbreviation: NAR System

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also called: North American Route (NAR)

Fr: réseau de routes aériennes nord-américaines
North Atlantic organized track system A variable track structure developed daily by appropriate Oceanic Area Control Centres (Gander [West] or Shanwick [East]) to create a series of minimum time tracks across the North Atlantic (NAT) taking into consideration weather, opposite direction traffic, danger areas, airspace reservations, usable NAVAIDs, aircraft volume and domestic routes.
. abbreviation: NAT OTS
Fr: système de routes organisées de l’Atlantique Nord
Northern Control Area
A controlled airspace within the Northern Domestic Airspace (NDA) at FL 230 and above.
. abbreviation: NCA
Fr: région de contr.le du Nord
Northern Domestic Airspace As geographically delineated in the Designated Airspace Handbook (DAH), a subdivision of Canadian Domestic Airspace (CDA) commencing at the North Pole and extending southward  to the northern limit of the Southern Domestic Airspace (SDA).
. abbreviation: NDA
Fr: espace aérien intérieur du Nord
North Warning System A system that provides airspace surveillance and command and control capability for air defence identification over the northern approaches to the continent. It consists of 15 long-range radars (LRR) and 39 short-range radars (SRR) across the Canadian Arctic and Alaska. Systems deployed on Canadian territory are operated and maintained by Canada for the Norht American Aerospace Defence Command (NORAD) on behalf of Canada and the United States.
. abbreviation: NWS
Fr: Système d’alerte du Nord
NOTAM A notice distributed by means of telecommunication containing information concerning the establishment, condition or change in any aeronautical facility, service, procedure or hazard,  the timely knowledge of which is essential to personnel concerned with flight operations. Fr: NOTAM
NOTAMJ Other expression for: RSC/CRFI NOTAM
notice to airmen U.S.: Expression for: NOTAM
no-transgression zone A corridor of airspace of defined dimensions, located centrally between the two extended runway centrelines, where controller intervention is required to manoeuvre the non-blundering aircraft when the airspace is penetrated by an aircraft conducting a simultaneous approach to the adjacent parallel or near-parallel instrument runway.