(See FLIGHT INFORMATION REGION.)
NATIONAL FLIGHT DATA CENTER- A facility in Washington D.C., established by FAA to operate a central aeronautical information service for the collection, validation, and dissemination of aeronautical data in support of the activities of government, industry, and the aviation community. The information is published in the National Flight Data Digest.
(See NATIONAL FLIGHT DATA DIGEST.)
NATIONAL FLIGHT DATA DIGEST- A daily (except weekends and Federal holidays) publication of flight information appropriate to aeronautical charts, aeronautical publications, Notices to Airmen, or other media serving the purpose of providing operational flight data essential to safe and efficient aircraft operations.
NATIONAL ROUTE PROGRAM (NRP)- The NRP is a set of rules and procedures which are designed to increase the flexibility of user flight planning within published guidelines.
NATIONAL SEARCH AND RESCUE PLAN- An interagency agreement which provides for the effective utilization of all available facilities in all types of search and rescue missions.
(See NAVIGATIONAL AID.)
NAVAID CLASSES- VOR, VORTAC, and TACAN aids are classed according to their operational use. The three classes of NAVAID's are:
a. T- Terminal.
b. L- Low altitude.
c. H- High altitude.
NOTE: The normal service range for T, L, and H class aids is found in the AIM. Certain operational requirements make it necessary to use some of these aids at greater service ranges than specified. Extended range is made possible through flight inspection determinations. Some aids also have lesser service range due to location, terrain, frequency protection, etc. Restrictions to service range are listed in Airport/Facility Directory.
NAVIGABLE AIRSPACE- Airspace at and above the minimum flight altitudes prescribed in the FAR's including airspace needed for safe takeoff and landing.
NAVIGATIONAL AID- Any visual or electronic device airborne or on the surface which provides point-to-point guidance information or position data to aircraft in flight.
(See AIR NAVIGATION FACILITY.)
(See NATIONAL BEACON CODE ALLOCATION PLAN AIRSPACE.)
(See NONDIRECTIONAL BEACON.)
NEGATIVE- "No," or "permission not granted," or "that is not correct."
NEGATIVE CONTACT- Used by pilots to inform ATC that:
a. Previously issued traffic is not in sight. It may be followed by the pilot's request for the controller to provide assistance in avoiding the traffic.
b. They were unable to contact ATC on a particular frequency.
(See NATIONAL FLIGHT DATA CENTER.)
(See NATIONAL FLIGHT DATA DIGEST.)
NIGHT- The time between the end of evening civil twilight and the beginning of morning civil twilight, as published in the American Air Almanac, converted to local time.
(See ICAO term NIGHT.)
NIGHT [ICAO]- The hours between the end of evening civil twilight and the beginning of morning civil twilight or such other period between sunset and sunrise as may be specified by the appropriate authority.
NOTE. Civil twilight ends in the evening when the center of the sun's disk is 6 degrees below the horizon and begins in the morning when the center of the sun's disk is 6 degrees below the horizon.
NO GYRO APPROACH- A radar approach/vector provided in case of a malfunctioning gyro-compass or directional gyro. Instead of providing the pilot with headings to be flown, the controller observes the radar track and issues control instructions "turn right/left" or "stop turn" as appropriate.
NO GYRO VECTOR-
(See NO GYRO APPROACH.)
NO TRANSGRESSION ZONE (NTZ)- The NTZ is a 2,000 foot wide zone, located equidistant between parallel runway final approach courses in which flight is not allowed.
NONAPPROACH CONTROL TOWER- Authorizes aircraft to land or takeoff at the airport controlled by the tower or to transit the Class D airspace. The primary function of a nonapproach control tower is the sequencing of aircraft in the traffic pattern and on the landing area. Nonapproach control towers also separate aircraft operating under instrument flight rules clearances from approach controls and centers. They provide ground control services to aircraft, vehicles, personnel, and equipment on the airport movement area.
NONCOMMON ROUTE/PORTION- That segment of a North American Route between the inland navigation facility and a designated North American terminal.
NONCOMPOSITE SEPARATION- Separation in accordance with minima other than the composite separation minimum specified for the area concerned.
NONDIRECTIONAL BEACON- An L/MF or UHF radio beacon transmitting nondirectional signals whereby the pilot of an aircraft equipped with direction finding equipment can determine his bearing to or from the radio beacon and "home" on or track to or from the station. When the radio beacon is installed in conjunction with the Instrument Landing System marker, it is normally called a Compass Locator.
(See COMPASS LOCATOR.)
(See AUTOMATIC DIRECTION FINDER.)
NONMOVEMENT AREAS- Taxiways and apron (ramp) areas not under the control of air traffic.
(See NONPRECISION APPROACH PROCEDURE.)
NONPRECISION APPROACH PROCEDURE- A standard instrument approach procedure in which no electronic glideslope is provided; e.g., VOR, TACAN, NDB, LOC, ASR, LDA, or SDF approaches.
NONRADAR- Precedes other terms and generally means without the use of radar, such as:
a. Nonradar Approach. Used to describe instrument approaches for which course guidance on final approach is not provided by ground-based precision or surveillance radar. Radar vectors to the final approach course may or may not be provided by ATC. Examples of nonradar approaches are VOR, NDB, TACAN, and ILS/MLS approaches.
(See FINAL APPROACH-IFR.)
(See FINAL APPROACH COURSE.)
(See RADAR APPROACH.)
(See INSTRUMENT APPROACH PROCEDURE.)
b. Nonradar Approach Control. An ATC facility providing approach control service without the use of radar.
(See APPROACH CONTROL FACILITY.)
(See APPROACH CONTROL SERVICE.)
c. Nonradar Arrival. An aircraft arriving at an airport without radar service or at an airport served by a radar facility and radar contact has not been established or has been terminated due to a lack of radar service to the airport.
(See RADAR ARRIVAL.)
(See RADAR SERVICE.)
d. Nonradar Route. A flight path or route over which the pilot is performing his own navigation. The pilot may be receiving radar separation, radar monitoring, or other ATC services while on a nonradar route.
(See RADAR ROUTE.)
e. Nonradar Separation. The spacing of aircraft in accordance with established minima without the use of radar; e.g., vertical, lateral, or longitudinal separation.
(See RADAR SEPARATION.)
(See ICAO term NONRADAR SEPARATION.)
NONRADAR SEPARATION [ICAO]- The separation used when aircraft position information is derived from sources other than radar.
(See NORTH PACIFIC.)
(See LOST COMMUNICATIONS.)
NORMAL OPERATING ZONE (NOZ)- The NOZ is the operating zone within which aircraft flight remains during normal independent simultaneous parallel ILS approaches.
NORTH AMERICAN ROUTE- A numerically coded route preplanned over existing airway and route systems to and from specific coastal fixes serving the North Atlantic. North American Routes consist of the following:
a. Common Route/Portion. That segment of a North American Route between the inland navigation facility and the coastal fix.
b. Noncommon Route/Portion. That segment of a North American Route between the inland navigation facility and a designated North American terminal.
c. Inland Navigation Facility. A navigation aid on a North American Route at which the common route and/or the noncommon route begins or ends.
d. Coastal Fix. A navigation aid or intersection where an aircraft transitions between the domestic route structure and the oceanic route structure.
NORTH MARK- A beacon data block sent by the host computer to be displayed by the ARTS on a 360 degree bearing at a locally selected radar azimuth and distance. The North Mark is used to ensure correct range/azimuth orientation during periods of CENRAP.
NORTH PACIFIC- An organized route system between the Alaskan west coast and Japan.
(See NOTICE TO AIRMEN.)
NOTICE TO AIRMEN- A notice containing information (not known sufficiently in advance to publicize by other means) concerning the establishment, condition, or change in any component (facility, service, or procedure of, or hazard in the National Airspace System) the timely knowledge of which is essential to personnel concerned with flight operations.
a. NOTAM(D)- A NOTAM given (in addition to local dissemination) distant dissemination beyond the area of responsibility of the Flight Service Station. These NOTAM's will be stored and available until canceled.
b. NOTAM(L)- A NOTAM given local dissemination by voice and other means, such as telautograph and telephone, to satisfy local user requirements.
c. FDC NOTAM- A NOTAM regulatory in nature, transmitted by USNOF and given system wide dissemination.
(See ICAO term NOTAM.)
NOTAM [ICAO]- A notice 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.
a. I Distribution- Distribution by means of telecommunication.
b. II Distribution- Distribution by means other than telecommunications.
NOTICES TO AIRMEN PUBLICATION- A publication issued every 28 days, designed primarily for the pilot, which contains current NOTAM information considered essential to the safety of flight as well as supplemental data to other aeronautical publications. The contraction NTAP is used in NOTAM text.
(See NOTICE TO AIRMEN.)
(See NOTICES TO AIRMEN PUBLICATION.)
NUMEROUS TARGETS VICINITY (LOCATION)- A traffic advisory issued by ATC to advise pilots that targets on the radar scope are too numerous to issue individually.
(See TRAFFIC ADVISORIES.)