(2)
NON-RADAR 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 Air Traffic Control. Examples of non-radar approach are VOR, NDB, TACAN, and Instrument Landing System/Microwave Landing System approach. (See Final Approach - IFR, Final Approach Course, Radar Approach, Instrument Approach Procedure)

(3)
NON-RADAR 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)

(4)
NON-RADAR 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, Radar Service)

(5)
NON-RADAR APPROACH CONTROL - An Air Traffic Control facility providing approach control service without the use of radar. (See Approach Control, Approach Control Service)

NON-RADAR SEPARATION (ICAO) - The separation used when aircraft position information is derived from sources other than radar.
NORDO - Non-radio equipped aircraft. Not to be used to designate aircraft which have radio failure.
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:
(1)
COMMON ROUTE/PORTION - That segment of a North American route between the inland navigation facility and the coastal fix.

(2)
NON-COMMON ROUTE/PORTION - That segment of a North American route between the inland navigation facility and a designated North American terminal.

(3)
INLAND NAVIGATION FACILITY - A navigation aid on a North American route at which the common route and/or the non-common route begins or ends.

(4)
COASTAL FIX - A navigation aid or intersection where an aircraft transitions between the domestic route structure and the oceanic route structure.

NORTH AMERICAN ROUTE PROGRAM (NRP) - The North American Route Program is a joint Federal Aviation Administration (FAA) and NAV CANADA program. The objective of the NRP is to harmonize and adopt common procedures, to the extent possible, applicable to random route flight operations at and above Flight Level 290 (FL290) within the conterminous United States and Canada. The procedures are published in FAA Advisory Circular 90-91H. Advisory Circulars are available through the FAA website at http://www.faa.gov. Any question on NRP procedures and altitudes should be forwarded to the ATC System Command Center, (ATCSCC) Herndon, VA at C703-904-4417.