Pilot/Controller Glossary

8/15/19

PCG N

−

1

N

NAS

−

(See NATIONAL AIRSPACE SYSTEM.)

NAT HLA–

(See NORTH ATLANTIC HIGH LEVEL

AIRSPACE.)

NATIONAL AIRSPACE SYSTEM

−

 The common

network of U.S. airspace; air navigation facilities,
equipment and services, airports or landing areas;
aeronautical charts, information and services; rules,
regulations and procedures, technical information,
and manpower and material. Included are system
components shared jointly with the military.

NATIONAL BEACON CODE ALLOCATION
PLAN AIRSPACE (NBCAP)

−

 Airspace over United

States territory located within the North American
continent between Canada and Mexico, including
adjacent territorial waters outward to about bound-
aries of oceanic control areas (CTA)/Flight
Information Regions (FIR).

(See FLIGHT INFORMATION REGION.)

NATIONAL FLIGHT DATA CENTER (NFDC)

−

 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 (NFDD)

−

 A

daily (except weekends and Federal holidays)
publication of flight information appropriate to
aeronautical charts, aeronautical publications, No-
tices to Airmen, or other media serving the purpose
of providing operational flight data essential to safe
and efficient aircraft operations.

NATIONAL SEARCH AND RESCUE PLAN

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 An

interagency agreement which provides for the
effective utilization of all available facilities in all
types of search and rescue missions.

NAVAID

−

(See NAVIGATIONAL AID.)

NAVAID CLASSES

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 VOR, VORTAC, and TACAN

aids are classed according to their operational use.
The three classes of NAVAIDs are:

a.

T

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 Terminal.

b.

L

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 Low altitude.

c.

H

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 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 Chart Supplement U.S.

NAVIGABLE AIRSPACE

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 Airspace at and above

the minimum flight altitudes prescribed in the CFRs
including airspace needed for safe takeoff and
landing.

(Refer to 14 CFR Part 91.)

NAVIGATION REFERENCE SYSTEM (NRS)

−

The NRS is a system of waypoints developed for use
within the United States for flight planning and
navigation without reference to ground based
navigational aids. The NRS waypoints are located in
a grid pattern along defined latitude and longitude
lines. The initial use of the NRS will be in the high
altitude environment in conjunction with the High
Altitude Redesign initiative. The NRS waypoints are
intended for use by aircraft capable of point

−

to

−

point

navigation.

NAVIGATION SPECIFICATION [ICAO]

−

 A set of

aircraft and flight crew requirements needed to
support performance

−

based navigation operations

within a defined airspace. There are two kinds of
navigation specifications:

a.

RNP specification. A navigation specification

based on area navigation that includes the
requirement for performance monitoring and
alerting, designated by the prefix RNP; e.g., RNP 4,
RNP APCH.

b.

RNAV specification. A navigation specifica-

tion based on area navigation that does not include the
requirement for performance monitoring and alert-