Section 2. Encode

EXPLANATION OF CODES

GEN - Indicates general aeronautical usage.

NWS - Indicates National Weather Service and aeronautical weather usage.

ATC - Indicates Air Traffic Control usage.

ICAO - Indicates International Civil Aviation Organization usage. International messages should use these.

METAR/TAF - Indicates ICAO weather usage.

A

Definition

Contraction

Usage

1 or 2 octas (eighths) cloud coverage

FEW

METAR

abandon

ABND

GEN

abbreviate

ABBR

GEN

Abbreviated precision approach path indicator

APAPI

ICAO

Abbreviated T visual approach slope indicator system

AT VASIS

ICAO

abeam

ABM

ICAO

abnormal

ABNML

GEN

aboard

ABD

GEN

about

ABT

GEN

above

ABV

ICAO

above aerodrome level

AAL

ICAO

above clouds

ACLD

GEN

above ground level

AGL

ICAO

above mean sea level

AMSL

GEN

above mountains

MON

ICAO

above sea level

ASL

GEN

above transmitted as received

ATAR

GEN

absolute (temperature)

A

NWS

abundant

ABNDT

GEN

accelerate

ACLT

GEN

accelerate- stop distance available

ASDA

ICAO

accept

ACPT

GEN

acceptance (message type designator)

ACP

ICAO

access

ACES

GEN

accident

ACDNT

GEN

accident notice

ACNOT

GEN

accompany

ACPY

GEN

account

ACCT

GEN

account mechanical

AMECH

GEN

account traffic

ATFC

GEN

account weather

AWX

GEN

accumulate

ACCUM

GEN

acknowledge

ACK

GEN

acknowledgement of receipt (message handling)

R

GEN

acrobatic

ACRBT

ATC

across

ACRS

GEN

acting

ACTG

GEN

activate

ACTVT

GEN

activate IFR flight plan

AIFP

ATC

activate VFR flight plan

AVFP

ATC

active

ACTV

GEN

active or activated or activity

ACT

ICAO

actual time of arrival

ATA

ATC

actual time of departure

ATD

ATC

actual time of penetration

ATP

ATC

actual time of release

ATRLS

ATC

actual wind factor

ALWF

NWS

addition

ADDN

GEN

additional

ADNL

GEN

additional traffic is

ADNL TFC

ATC

address

ADS

GEN

adequate

ADQT

GEN

adirondack

ADRNDCK

NWS

adjacent

ADJ

ICAO

administration

ADMIN

GEN

administrative

ADMIV

GEN

administrator

ADMIR

GEN

advance

ADVN

GEN

Advance boundary information

ABI

ICAO

Advanced Navigation Routes

ANR

ATC

advection

ADVCTN

NWS

advice

ADVC

GEN

advise

ADV

NWS

advise

ADZ

ICAO

advise arrival

ADZAR

ATC

advise at what time able

AAWTA

ICAO

advise by air mail as soon as possible

ADMAP

GEN

advise customs

ADCUS

GEN

advise disposition

ADSPN

GEN

advise if able

AIA

ATC

advise if able to proceed

AAP

ATC

advise if not correct

ADNOK

ATC

advise intentions

ADZI

ATC

advise or issue instructions to all concerned

ADCON

GEN

advise present position and altitude

APPA

ATC

advise reason for delay

ADRDE

ATC

advise this office

ADZOF

GEN

advise when able

AWA

ATC

advise when established

AWE

ATC

advisory

ADVY

NWS

advisory

ADZY

GEN

advisory

ADZY

ATC

advisory

ADVZY

ATC

advisory area

ADA

ATC

Advisory Circular

AC

GEN

advisory route

ADR

ATC

aerial

ARL

ATC

aerodrome

AD

ICAO

aerodrome beacon

ABN

ICAO

Aerodrome chart

ADC

ICAO

aerodrome control tower

TWR

ICAO

aerodrome flight information service

AFIS

ICAO

aerodrome forecast

TAF

ICAO

aerodrome obstacle chart (followed by type & name/title)

AOC

ICAO

Aerodrome office (specify service)

ADO

ICAO

aerodrome reference point

ARP

ICAO

aerodrome traffic zone

ATZ

ICAO

aerodromes, air routes and ground aids

AGA

ICAO

aeronautical

AERO

GEN

Aeronautical chart 1:500 000 (followed by name/title)

ANC

ICAO

aeronautical fixed service

AFS

GEN

Aeronautical Fixed Telecommunications Network

AFTN

GEN

Aeronautical Information Circular

AIC

GEN

Aeronautical Information Publication

AIP

ATC

aeronautical information publications (In General)

AIP

GEN

aeronautical information regulation and control

AIRAC

GEN

aeronautical information service

AIS

GEN

aeronautical information specialist

AIS

GEN

aeronautical maps and charts

MAP

ICAO

aeronautical mobile satellite service

AMSS

ICAO

aeronautical mobile service

AMS

GEN

Aeronautical navigation chart small scale (followed by name/title scale)

ANCS

ICAO

Aeronautical Radio, Incorporated

ARINC

GEN

Aeronautical Telecommunications Network

ATN

ICAO

aeronautical telecommunications operator

ATO

GEN

affect

AFCT

GEN

affirmative

AFIRM

GEN

affirmative

AFM

ICAO

After

AFT

GEN

after dark

AFDK

NWS

after passing

APSG

ICAO

Afternoon

AFTN

GEN

Again

AGN

GEN

Aggregate demand list

ADL

ATC

Agree

AGR

GEN

agreement

AGRMT

GEN

Ahead

AHD

GEN

air carrier

ACR

GEN

Air Carrier District Office

ACDO

GEN

air combat maneuvers

ACM

ATC

air combat training

ACT

ATC

Air Defense Control Facility

ADCF

GEN

Air Defense Emergency

ADE

GEN

air defense identification zone

ADIZ

GEN

Air Defense Liaison Officer

ADLO

GEN

Air Defense Sector

ADS

GEN

air defense warning

ADW

GEN

air evacuation

AEVAC

ATC

air express

AXPS

GEN

Air Force Base

AFB

GEN

Air Force Communications Network

AIRCOMNET

GEN

Air Force Jet

AFJ

ATC

Air Force NOTAM Exchange Area

AFNEA

GEN

Air Force NOTAM Exchange Office

AFNEO

GEN

Air Force overrun 1000 ft standard approach lighting system

AFOVRN

MIL

Air Force Representative to the FAA

AFREP

GEN

Air Force Rescue Coordination Center

AFRCC

GEN

air freight

AFRT

GEN

air ground

AG

ATC

Air Line Dispatchers Association

ALDA

GEN

Air Line Pilots Association

ALPA

GEN

air mass

AMS

NWS

Air Mobility Command

AMC

ATC

Air National Guard

ANG

GEN

air navigation facility

ANF

GEN

air navigation radio aids

ANRA

GEN

air operations network

AIROPNET

GEN

air refueling

AIRFL

ATC

air refueling control point

ARCP

ATC

air refueling egress point

AREP

ATC

air refueling exit

AREX

ATC

air refueling initial point

ARIP

ATC

air report

AIREP

GEN

Air Rescue Service (USAF)

ARS

GEN

Air Reserve Base

ARB

GEN

air route surveillance radar

ARSR

GEN

air route traffic control

ARTC

GEN

Air Route Traffic Control Center

ARTCC

GEN

air to air

A/A

ATC

air to ground

A/G

ICAO

air traffic control

ATC

ICAO

Air Traffic Control Association

ATCA

GEN

air traffic flow management

ATFM

ICAO

air traffic management

ATM

ICAO

air traffic manager

ATM

ATC

Air Traffic Organization

ATO

GEN

air traffic procedures

ATP

GEN

Air Traffic Procedures Advisory Committee

ATPAC

GEN

air traffic representative

ATREP

GEN

Air Traffic Service Contingency Command Post

ATSCCP

GEN

Air traffic services inter facility data communication

AIDC

ICAO

air traffic services reporting office

ARO

GEN

Air Transport Association of America

ATA

GEN

air transport pulse radar navigation aid

CPN

GEN

air transport pulse radar search

CPS

GEN

air transport rating

ATR

GEN

air weather service (USAF)

AWS

GEN

airborne

AB

ATC

airborne collision avoidance system

ACAS

ICAO

airborne early warning

AEW

GEN

airborne launching

ABLCHG

ATC

airborne pulse search radar

APS

GEN

Airborne Radar Unit

ARU

GEN

aircraft

ACFT

ICAO

aircraft and engine mechanic

AEM

GEN

aircraft classification number

ACN

ICAO

Aircraft communication addressing & reporting system

ACARS

ICAO

aircraft control and warning

ACW

GEN

aircraft departing at (number of minutes) intervals

ADMIS

ATC

aircraft earth station

AES

ICAO

aircraft identification

ACID

ATC

aircraft movement information services

AMIS

GEN

aircraft out of commission for parts

AOCP

GEN

Aircraft Owners and Pilots Association

AOPA

GEN

Aircraft parking/docking chart (followed by name/title)

APDC

ICAO

aircraft rescue and fire fighting

ARFF

ATC

airmail

ARML

GEN

Airman s Information Manual

AIM

GEN

Airmen s Meteorological Information

AIRMET

GEN

AIRMET

WA

NWS

airport

AP

ICAO

airport

ARPT

GEN

airport acceptance rate

AARTE

ATC

airport arrival rate

AAR

ATC

airport departure rate

ADR

ATC

Airport Development Aid Program

ADAP

GEN

Airport District Office

ADO

GEN

airport in sight

AIS

GEN

airport information desk

AID

GEN

airport layout plan

ALP

GEN

airport lights

APL

GEN

airport manager

AMGR

GEN

airport of entry

AOE

GEN

airport operating certificate

AOC

GEN

airport radar service area

ARSA

ATC

airport reference point

ARP

GEN

airport rescue and fire fighting alarm checked

ARFFOK

ATC

airport reservation position

ARP

GEN

Airport Reservations Office

ARO

GEN

airport surface detection equipment

ASDE

GEN

airport surveillance radar

ASR

GEN

airport system plan

ASP

GEN

Airport Traffic Control Tower

ATCT

GEN

airports program report

APR

GEN

air-report

ARP

GEN

Airspace

ASP

GEN

airspace docket

ASD

GEN

airspace flight inspection pilot

ASIP

GEN

Airspace Reservation Unit (Canadian)

ARU

GEN

airway

AWY

ICAO

airways engineer

AENG

GEN

Alaskan Air Command

AAC

GEN

Alaskan Region, FAA

AAL

GEN

Alaskan Standard Time (time groups only)

A

NWS

Alberta

ALTA

NWS

alert notice

ALNOT

GEN

alert phase code (alerting service)

ALERFA

ATC

alerting

ALR

ICAO

Aleutian

ALUTN

NWS

alighting area

ALA

GEN

alignment

ALNMT

GEN

all (when used as prefix)

AL

GEN

all accident notice offices

ALANO

GEN

all air carrier field offices

ALACFO

GEN

all air defense liaison officers in service area

ALADLO

GEN

all air route traffic control centers in service area

ALARTC

GEN

all air traffic (area) supervisors in service area

ALATAS

GEN

all air traffic field facilities

ALATF

GEN

all air traffic field offices

ALATFO

GEN

all air traffic service personnel in service area

ALAT

GEN

all technical operations

ALAFFO

GEN

all air traffic combined station/centers in service area

ALCS/C

GEN

all air traffic combined station/towers in service area

ALCS/T

GEN

all ATC towers in service area

ALTWR

GEN

all concerned notified

ACN

GEN

all FAA field offices and personnel

ALFAA

GEN

all FAA offices on NADIN

ALFAB

GEN

all flight service stations in service area

ALFSS

GEN

all flight standards field offices

ALFSFO

GEN

all international aeronautical telecommunication switching centers

ALIATSC

GEN

all international air traffic switching centers

AIATSC

GEN

all international field offices

ALIFO

GEN

all international flight service stations in service area

ALIFSS

GEN

all offices having send receive teletypewriter service on circuit

ALCKT

GEN

all quadrants

ALQDS

NWS

all radar ATC facilities in service area

ALRAFAC

GEN

all regional/service area offices

ALRGN

GEN

all sectors

ALSEC

NWS

all technical operations

ALAFFO

GEN

all up weight (gross weight)

AUW

GEN

all weather landing

AWL

ATC

Allegheny

ALGHNY

NWS

allotment advice

ADVALT

GEN

allowable take off gross weight

ATOG

GEN

aloft

ALF

NWS

along

ALG

GEN

already had

A/H

ATC

alternate

ALTN

GEN

alternate (aerodrome)

ALTN

ICAO

alternate airport

ALTPT

GEN

alternate departure route

ADRT

ATC

altimeter

ALTM

GEN

altimeter check location

ACL

ATC

altimeter setting

ALSTG

GEN

altimeter setting indicator

ASI

GEN

altimeter sub scale setting to obtain elevation when on the ground

QNH

ICAO

Altimetry system error

ASE

ICAO

altitude

ALT

ICAO

altitude radial

ARAD

ATC

altitude reservation

ALTRV

GEN

altitude reservation void for aircraft not airborne by

AVANA

ATC

altocumulus

AC

NWS

altocumulus castellanus

ACCAS

NWS

altostratus

AS

NWS

amber

A

GEN

ambiguity

AMB

GEN

amend / amended forecast

AMD

GEN/

amended clearance

AMCL

ATC

amended route of flight

AMRF

ATC

amendment

AMDT

ICAO

American Meteorological Society

AMS

NWS

American Telephone and Telegraph Company

ATT

GEN

amount

AMT

GEN

amplifier or amplify

AMP

GEN

amplitude

AMPLTD

NWS

analysis

ANLYS

NWS

announce

ANNC

GEN

annual leave

AL

GEN

anomalous propagation

AP

ATC

answer

ANS

GEN

ante meridiem

AM

NWS

antenna

ANT

GEN

anticipate

ANCPT

GEN

anticyclonic

ACYC

NWS

Appalachian

APLCN

NWS

apparent

APRNT

GEN

appear

APPR

GEN

appoint

APNT

GEN

approach

APCH

ICAO

approach and departure control

AADC

ATC

approach control

A/C

ATC

approach control or approach control office

APP

ICAO

approach end runway

AER

GEN

approach light lane

YL

ATC

approach light system

ALS

ICAO

approach path alignment panel

APAP

GEN

Appropriate

APROP

GEN

Approval

APVL

GEN

approval request

APREQ

GEN

approve

APV

GEN

approximate

APRX

GEN

Apron

APN

ICAO

arctic (air mass)

A

NWS

area airports checked

ARAC

ATC

Area chart

ARC

ICAO

area command post

ACP

GEN

area control center

ACC

ATC

area forecast

ARFOR

GEN

area forecast

FA

NWS

area forecast center

AFC

NWS

area minimum altitude

AMA

ICAO

area navigation

RNAV

ICAO 

area notice

ARNOT

GEN

area positive control

APC

ATC

Army Air Field

AAF

GEN

Army Liaison Officer

ARLO

GEN

Army National Guard

RNG

GEN

Army Radar Approach Control facility (US Army)

ARAC

GEN

around

ARND

GEN

arrange

ARNG

GEN

arrest

ARST

GEN

arresting

ARST

ICAO

arresting gear

A GEAR

GEN

arrival aircraft interval

AAITVL

ATC

arrival approved request for IFR flight

AI

ATC

arrival delay

ADLY

ATC

arrival or arrive

ARR

ICAO

arrival report will be filed with

FIRIV

ATC

arrival unknown

ARUNK

ATC

artic control area

ACA

ATC

as soon as possible

ASAP

GEN

as soon as possible

SAP

ICAO

ascend

ASND

GEN

ascent to

ASC

GEN

ASOS automated observation with precipitation discriminator (rain/snow)

AO2

NWS

ASOS automated observation without precipitation discriminator (rain/snow)

AO1

METAR

asphalt

ASPH

ICAO

assign

ASGN

GEN

Assigned altitude deviation

AAD

ICAO

assistant

ASST

GEN

assistant chief

AC

GEN

associate

ASSOC

GEN

assumed

ASMD

ATC

at all times

AATM

GEN

at and maintain

ATAM

ATC

at least (altitude)

AL/( )

ATC

at or above

AOA

ATC

at or after

AOAF

ATC

at or before

AOBF

ATC

at or below

AOB

ATC

at sea

MAR

ICAO

at the coast

COT

ICAO

at this time

ATTM

GEN

ATC advises

ATCA

ATC

ATC assigned airspace

ATCAA

ATC

ATC beacon interrogator

ATCBI

GEN

ATC clears

ATCC

ATC

ATC facility

ATCF

GEN

ATC operations representative

ATCOR

GEN

ATC radar beacon system

ATCRBS

GEN

ATC requests

ATCR

ATC

ATC specialist

ATCS

GEN

ATC tower, approach and departure control facility

TAD

ATC

Atlantic

ATLC

NWS

Atlantic Route

AR

ATC

atmospheric pressure at airport elevation

QFE

ICAO

atmospherics

SFERICS

NWS

atmospherics

XS

ICAO

ATS/MET reporting point

MRP

ICAO

Attach

ATCH

GEN

Attempt

ATMT

GEN

attempt to contact

ATMTC

ATC

attempt to locate

ALCT

GEN

Attend

ATND

GEN

Attention

ATTN

GEN

Aurora Borealis

AURBO

NWS

authentication maneuver

ATM

ATC

Authority

AUTH

GEN

authority granted

AUGRA

GEN

authority is requested

AUREQ

GEN

authorization for interceptor operations

AFIO

ATC

Authorize

AUZ

GEN

authorized or authorization

AUTH

ICAO

automated flight information service

FISA

ICAO

Automated Mutual Assistance Vessel Rescue System

AMVER

ATC

Automated Radar Terminal Systems

ARTS

GEN

automated surface observing system

ASOS

NWS

automatic

AUTO

ICAO

automatic broadcast

ABCST

GEN

automatic carrier landing system

ACLS

GEN

automatic data processing

ADP

GEN

automatic data processing equipment

ADPE

GEN

automatic data processing systems

ADPS

GEN

automatic dependent surveillance

ADS

ICAO

Automatic Dependent Surveillance-Broadcast

ADS-B

ICAO

automatic dependent surveillance unit

ADSU

ICAO

automatic direction finder

ADF

GEN

automatic direction finder approach

ADFAP

ATC

automatic error correction equipment

ARQ

GEN

automatic ground air/ground communication system

AGACS

GEN

automatic instrument landing system

AILS

GEN

Automatic Meteorological Observing System

AMOS

GEN

Automatic Network Management System

ANMS

GEN

automatic scanning control unit

ASCU

GEN

automatic scanning unit out of service

SCANO

GEN

automatic scanning unit returned to service

SCAOK

GEN

automatic send/receive

AS/R

GEN

automatic terminal information service

ATIS

ICAO

automatic weather broadcast equipment

AWBE

GEN

automatic weather observing/reporting system

AWOS

GEN

automatic weather reporting system

AUTOB

GEN

auxiliary

AUX

GEN

Auxiliary Aviation Weather Facility

AAWF

NWS

Auxiliary Flight Service Station

XFSS

ATC

auxiliary report

XREP

GEN

available or availability

AVBL

ICAO

average

AVG

GEN

aviation

AVN

GEN

Aviation Area Forecast Center

FA CENTER

GEN

aviation gasoline

AVGAS

ICAO

aviation routine weather report

METAR

ICAO

aviation selected special weather report

SPECI

METAR

Aviation Weather and NOTAM System

AWANS

GEN

aviation weather processors

AWP

NWS

await or awaiting

AWT

GEN

azimuth

AZM

ICAO

azimuth and range data

AZRAN

ATC

,

B

Definition

Contraction

Usage

back course

BC

GEN

back course marker

BCM

GEN

back taxiing

BT

ATC

backing

BCKG

NWS

backup emergency communication

BUEC

GEN

backup interceptor control

BUIC

ATC

Bahama Route

BR

ATC

balance

BAL

GEN

balloon

BLN

GEN

baroclinic or baroclinic prognosis

BACLIN

NWS

barometer

BRM

NWS

barotropic or barotropic prognosis

BATROP

NWS

base leg

B

ATC

base of overcast

BOVC

NWS

Base Operations Office

BASOPS

GEN

basic meteorological services

BMS

NWS

beach

BCH

NWS

beacon

BCN

ICAO

beacon data (digitized)

BDAT

ATC

bearing

BRG

GEN

become

BCM

GEN

becoming (expected between 2 digit beginning hour and 2 digit ending hour)

BECMG

TAF

Before

BFR

GEN

before dark

BFDK

NWS

before encountering IFR conditions

BIFR

ATC

before proceeding on course

BPOC

ATC

began or begin

BGN

GEN

begin or beginning descent

BGND

ATC

begin standard refuel orbit

BSRO

ATC

beginning climb

BC

ATC

beginning of precipitation (time in minutes) (weather reports only)

B

NWS

beginning procedure turn

BPT

ATC

beginning standard holding procedure

BSHP

ATC

beginning standard range approach

BSRAP

ATC

beginning straight in approach

BSIAP

ATC

Behind

BHND

GEN

Below

BLO

GEN

Below

BLW

ICAO

below all clouds

BAC

ATC

below clouds

BLO

ICAO

beneath

BNTH

GEN

Bering Standard Time (time groups only)

B

NWS

Berkshire

BRKSHR

NWS

Bermuda

BDA

NWS

Better

BTR

GEN

Between

BTN

ICAO

Between

BTWN

NWS

between layers

BTL

ICAO

Beyond

BYD

GEN

bids accepted for the following vacancies

BAFVC

GEN

bids solicited

BDSLD

GEN

bids solicited as follows

BSAF

GEN

bird sweep completed

BSC

ATC

Black Hills

BLKHLS

NWS

Blanket

BLKT

NWS

Blizzard

BLZD

NWS

Block

BLX

ATC

Blowing

BL

METAR

blowing dust

BLDU

METAR

blowing sand

BLSA

METAR

blowing snow

BLSN

METAR

blowing spray (weather reports only)

BY

METAR

Blue

B

GEN

Bomber

BMBR

GEN

Bombing

BOMB

GEN

Border

BDR

GEN

Bound

BND

GEN

Boundary

BDRY

ATC

boundary

BNDRY

ICAO

braking

BRKG

ICAO

braking action

BA

ICAO

braking action good

BRAG

GEN

braking action medium

BRAM

GEN

braking action nil

BRAN

GEN

braking action poor

BRAP

GEN

branch

BR

GEN

break

BRK

NWS

breaks in higher overcast

BRKHIC

NWS

breaks in overcast

BINOVC

NWS

brief

BRF

NWS

bright

BRGT

GEN

bright radar indicator tower equipment

BRITE

GEN

British Columbia

BC

NWS

broadcast

BCST

ICAO

broadcast requested

BCREQ

ATC

broadcast station

BCSTN

GEN

broken

BKN

METAR

build

BLD

NWS

building

BLDG

ICAO

buildup

BLDUP

NWS

bulletin

BUL

GEN

bureau

BUR

GEN

business

BUS

GEN

buzzer (radar)

BZR

GEN

by visual reference to the ground

VSA

ICAO

by way of

VIA

GEN

bytes per second

BPS

GEN

,

C

Definition

Contraction

Usage

calibration

CLBR

ICAO 

calibration performance monitoring equipment

CPME

ATC

Call sign

CS

ICAO

Calling

CLG

ICAO

Canada

CAN

NWS

Canadian

CNDN

NWS

Canadian Airspace Reservation Unit

CARU

GEN

Canadian Armed Force

CANFORCE

GEN

Canadian Armed Forces Transport Command

CAM

GEN

Canadian Forces Air Defense Command

CFADC

GEN

Canadian NORAD Region

CANR

GEN

Canadian NOTAM

CANOT

GEN

cancel

CNCL

NWS

cancel

CNL

GEN

cancel approved arrival

CXA

ATC

cancel approved departure

CXD

ATC

cancel flight plan

CNLFP

ATC

cancel IFR clearance previously given

CIFR

ATC

cancel IFR flight plan

CIFP

ATC

cancel VFR flight plan

CVFP

ATC

candela

CD

ICAO

capable

CPBL

GEN

capacity

CPTY

GEN

captain

CAPT

GEN

carbon copy

CC

GEN

Caribbean

CARIB

NWS

carryover from previous log

CFPL

ATC

cascades

CASCDS

NWS

catalogue number

CANO

GEN

category

CAT

ICAO

category

CTGY

NWS

cathode ray tube

CRT

GEN

Catskills

CTSKLS

NWS

caution

CTN

GEN

caution advised until further notice

CAUFN

GEN

ceiling

CIG

NWS

celestial

CLST

ATC

celestial navigation

CELNAV

GEN

celsius

C

GEN

center

CNTR

GEN

center clearance delivered

B

ATC

centerline

CNTRLN

GEN

centimeter

CM

ICAO

central

CNTRL

GEN

central altitude reservation function

CARF

GEN

Central Computer Complex

CCC

GEN

central flow weather service unit

CFWSU

GEN

Central North Pacific

CENPAC

ATC

Central Region, FAA

ACE

GEN

Central Standard Time (time groups only)

C

NWS

central weather service unit

CWSU

GEN

centre (runway ID)

C

ICAO

centre line

CL

ICAO

certificate

CERT

GEN

certification

CERTIF

GEN

certify

CRTFY

GEN

chance

CHC

NWS

change

CHG

GEN

change frequency to

CF

ICAO

change of appointing office

CAO

GEN

change to approach control or changing to approach control

CAC

ATC

change to center control or changing to center control

CTCC

ATC

change weight manifest

CWM

GEN

changeover

CHOV

ATC

changeover point

COP

GEN

changing over

CHGO

ATC

channel

CH

ICAO

channel

CHNL

GEN

chapter

CHAP

GEN

characteristic

CHARC

GEN

charge

CHRG

GEN

charter

CHTR

GEN

check

CK

ICAO

check area airports

CARA

GEN

check okay

CHOK

GEN

chemicals

CHM

GEN

Chesapeake

CHSPK

NWS

chief controller

CCTLR

GEN

Chief, Airport District Office

CADO

GEN

circle

CRC

GEN

circling (approach and landing charts)

C

ATC

circling guidance light

CGL

ICAO

circuit

CKT

GEN

circuit line up

CLU

GEN

circuit notice

CIRNOT

GEN

circular polarization

CP

GEN

circulate

CRLC

GEN

circumnavigate

CIRNAV

ATC

cirrocumulus

CC

NWS

cirrostratus

CS

NWS

cirrus

CI

NWS

City (or County) Civil Defense Director at____

CCD

GEN

civil

CIV

ICAO

civil air carrier turbojet

CACT

GEN

Civil Air Patrol

CAP

GEN

civil defense

CD

GEN

civil engineer

CENGR

GEN

civil reserve air fleet

CRAF

GEN

clarify

CFY

GEN

Class A Airspace

CAAS

ATC

Class B airspace

CBAS

ATC

Class B surface area

CBSA

ATC

Class C airspace

CCAS

ATC

Class C surface area

CCSA

ATC

Class D airspace

CDAS

ATC

Class D surface area

CDSA

ATC

Class E airspace

CEAS

ATC

Class E surface area

CESA

ATC

Class G airspace

CGAS

ATC

clears, or cleared to, or clearance

CLR

ICAO

clear above (PIREP only)

CA

ATC

clear air turbulence

CAT

GEN

clear and smooth

CLRS

NWS

clear of clouds

CCLDS

ATC

clear or scattered clouds and visibility greater than ten miles

CAVU

NWS

clear or scattered clouds and visibility greater than ten, remainder of report missing (weather reports only)

DCAVU

NWS

clear type of ice formation

CLA

ICAO

clearance

CLNC

GEN

clearance delivery

CD

GEN

clearance void if not off

CVINO

ATC

cleared as planned

CLRAP

ATC

cleared Customs

CCUS

GEN

cleared for approach

CFAP

ATC

cleared to fix

F

ATC

clearway

CWY

ICAO

climb

CLB

ATC

climb and cross

CATX

ATC

climb and cruise

CCRZ

ATC

climb at pilot s discretion

CAPD

ATC

climb en route

CER

ATC

climb immediately

CLBI

ATC

climb on course

COC

ATC

climb so as to cross

CSATX

ATC

climb so as to reach

CSATR

ATC

climb to and cross

CTAX

ATC

climb to and maintain

CTAM

ATC

climb to or climbing to

CMB

ICAO

climb well to right

CWTR

ATC

climb well to right of course

CWRC

ATC

clockwise

CLKWS

GEN

clockwise orbit

CLKOB

ATC

close of business

COB

GEN

close this office

CLOTO

GEN

closed

CLSD

ICAO 

closing date

CLODA

GEN

closing station

CL

GEN

cloud

CLD

NWS

cloud and visibility OK

CAVOK

NWS

cloud base

BASE

GEN

cloud top

TOP

NWS

Coarse/Acquisition

C/A

ATC

coast

CST

NWS

Coast Guard

CG

GEN

Coast Guard Air Station

CGAS

GEN

Coast Guard LORAN Station

CGLS

GEN

coastal zone management

CZM

GEN

Cockpit voice recorder

CVR

ICAO

Code of Federal Regulations

CFR

GEN

cold (air mass)

K

NWS

cold front

CDFNT

NWS

cold front passage

CFP

NWS

collaborative convective forecast product

CCFP

ATC

collaborative decision making

CDM

ATC

collect

COLL

GEN

collision avoidance system

CAS

GEN

colon

CLN

GEN

combine

COMB

GEN

combined approach control/international station

CAP/IS

GEN

combined center/RAPCON

CERAP

GEN

combined station/center

CS/C

GEN

combined station/tower

CS/T

GEN

comma

CMA

GEN

Commander in Chief, North American Aerospace Defense Command

CINCNORAD

GEN

commence

CMNC

GEN

commercial

COML

GEN

commercial broadcasting station

BS

ICAO

commission

CMSN

GEN

common aviation weather subsystem

CAWS

NWS

common ICAO data interchange network

CIDIN

ICAO

Common IFR Room

CIFRR

GEN

common terminal radar approach control

CTRAC

GEN

common traffic advisory frequency

CTAF

ATC

communication

COM

ICAO

communications duty officer

CDO

GEN

communications equipment

CE

GEN

communications instructions for reporting vital intelligence sightings

CIRVIS

ATC

communications, navigation and surveillance

CNS

ICAO

compact

CMPCT

GEN

company

CO

GEN

compare

COMPR

GEN

compartment

COMPRT

GEN

compass locator

COMLO

GEN

compass locator at ILS middle marker

LMM

GEN

compass locator at ILS outer marker

LOM

GEN

complete

CMPLT

GEN

complete crew

CCRU

GEN

complete or completed or completion

CMPL

ICAO

complete power failure

CPF

GEN

completed procedure turn

COPT

ATC

complex

CMPLX

GEN

component

CMPT

GEN

composite flight data processing

CFAD

GEN

composite radar data processing

CRAD

GEN

composition

CMPSN

GEN

computer display channel

CDC

GEN

computerized voice reservation system

CVRS

ATC

concrete

CONC

ICAO

concurrently

CNCNT

GEN

condensation trails

CONTRAILS

NWS

condition

COND

ICAO

confidence

CONFDC

NWS

confidential

CONF

GEN

configuration

CONFIGN

GEN

configuration

CONFIG

ATC

confine

CFN

GEN

confirm

CFM

GEN

Confirm or I confirm

CFM

ICAO

confirming requisition follows

COREQ

GEN

congestion

CGSTN

GEN

connect

CNCT

GEN

consider

CSDR

GEN

considerable

CSDRBL

GEN

consistent

CNSTNT

GEN

consol beacon

CONSOL

GEN

CONSOLAN Facility

CONSO

GEN

consolidate

CSLDT

GEN

Consolidated NOTAM System

CNS

ATC

construction

CONST

ICAO

construction maintenance supervisor

CMS

GEN

contact

CTC

ICAO

contact approach control

CAC

ATC

contact center

CTCEN

ATC

contact center control

CTCC

ATC

continental (air mass)

C

NWS

continental control area

CCA

GEN

Continental Divide

CONTDVD

NWS

Continental NORAD Region

CONR

GEN

continue calling until

CONCA

ATC

continue(s) or continued

CONT

ICAO

continue to hold

CONTH

ATC

continuous

CONS

ICAO

continuous 24 hour service

H24

ICAO

continuous wave

CW

ICAO

contract

CONTR

GEN

control

CTL

ICAO

control area

CTA

ICAO

control area

CTLA

GEN

control boundary

CTLB

GEN

control zone

CTLZ

GEN

control zone

CTR

ICAO

controlled airspace

CTAS

ATC

controlled firing area

CFA

ATC

controller

CTLR

GEN

controller in charge

CIC

GEN

Controller pilot data link communications

CPDLC

ICAO

Controllers Operations and Procedures Committee

COPCOM

GEN

convective

CNVTV

NWS

convene

CVN

GEN

converge

CNVG

GEN

conversion

CNVSN

GEN

convert

CNVRT

GEN

coordinate

COORD

GEN

Coordinated Universal Time

UTC

ICAO

Coordinated Universal Time Coordinate Check Completed

UTCOK

GEN

Coordinates

COORD

ICAO

coordination

CDN

ICAO

correct or corrected or correction

COR

GEN

corridor assignment

CORAS

ATC

counterclockwise

CCLKWS

NWS

counterclockwise orbit

CCLKOB

ATC

county

CO

GEN

coupled

CPD

GEN

course

CRS

GEN

course line

CL

ATC

cover

COV

ICAO

cover

CVR

GEN

crash locator beacon

CLBN

GEN

crash phone activated

CPA

GEN

crew chief

CRCHF

GEN

cross

X

ICAO

cross talk

XTLK

ATC

crossbar

XBAR

ICAO

crossing

XNG

ICAO

crosswind

XW

ATC

cruise

CRZ

ICAO

cruise and maintain

CRZAM

ATC

cruise well to right

CRZWTR

ATC

Cryptographic

CRYPTO

GEN

Crystal

XTAL

GEN

Cumuliform

CUF

ICAO

Cumulonimbus

CB

NWS

cumulonimbus mamma

CBMAM

NWS

Cumulus

CU

NWS

cumulus fractus

CUFRA

NWS

current flight plan

CPL

ICAO

Customs

CUST

ICAO

customs has been notified

CUSNO

GEN

Cyclic redundancy check

CRC

ICAO

Cyclogenesis

CYCLGN

NWS

Cyclonic

CYC

NWS

Cylinder

CYL

GEN

,

D

Definition

Contraction

Usage

Daily

DLY

GEN

Daily

DLY

ICAO

daily flight log

DFL

GEN

Dakotas

DKTS

NWS

damage

DMG

GEN

danger

DGR

GEN

danger

DNG

ICAO

danger area

D

ICAO

dangerous cargo

DGCGO

GEN

data link

DOLLY

GEN

Data link Automatic Terminal Information Service

D ATIS

ICAO

Data link initiation capability

DLIC

ICAO

Data link VOLMET

D VOLMET

ICAO

data terminal equipment

DTE

GEN

data transmission feature

DTF

GEN

data transmission request

DTR

GEN

date of birth

DOB

GEN

date time group

DTG

GEN

Davide J. Hurley ATC System Command Center

ATCSCC

GEN

daybreak

DABRK

NWS

daylight

DALGT

GEN

dead reckoning

DR

ATC

decelerate

DCLRT

ATC

decibel

DB

GEN

decision altitude

DA

ICAO

decision height

DH

ICAO

decommission

DCMSN

GEN

decrease

DCR

GEN

deep

DP

NWS

deepening

DPNG

NWS

defense

DEF

GEN

defense combat maneuvers

DCM

ATC

Defense Commercial Communications Office

DECCO

GEN

Defense Communications Agency

DCA

GEN

defense communications system

DCS

GEN

Defense Mapping Agency Aerospace Center

DMAAC

GEN

Defense Mapping Agency Hydrographic Center

DMAHC

GEN

Defense Nuclear Agency

DNA

GEN

Defense Readiness Conditions

DEFCON

GEN

Defense Switching Network

DSN

GEN

defense VFR

DVFR

GEN

definite

DFNT

GEN

degree

DEG

ICAO

delay or delayed

DLA

ICAO

delay account of

DLAC

ATC

delay clearance or delayed clearance

DLC

ATC

delay indefinite

DI

ATC

delay time

DLAT

ATC

delayed

RTD

ICAO

delete

DLT

GEN

deliver

DLVR

GEN

deliver by telephone

DELPHO

GEN

delivery

DLVY

GEN

demolition

DEMOL

GEN

demonstration

DMSTN

GEN

dense

DNS

NWS

dense upper cloud

DUC

ICAO

depart

DEP

ATC

department

DEPT

GEN

Department of Commerce

DOC

GEN

Department of Defense

DOD

GEN

Department of Energy

DOE

GEN

Department of Transportation

DOT

GEN

departure

DEP

ICAO
departure end of runway DER ICAO

departure approval request for IFR flight

DI

ATC

departure approved

DA

ATC

departure procedure

DPCR

ATC

Deployment Readiness Review

DRR

ATC

depth

DPT

ICAO

depth

DPTH

NWS

deputy chief

DCF

GEN

Deputy Commander for Operations

DO

GEN

descend

DSND

ATC

descend at pilot s discretion

DAPD

ATC

descend immediately

DSNDI

ATC

descend so as to cross

DSATX

ATC

descend so as to reach

DSATR

ATC

descend to and cross

DTAX

ATC

descend to and cruise

DCRZ

ATC

descend to and maintain

DTAM

ATC

descend to or descending to

DES

ICAO

descend well to right

DWTR

ATC

descend well to right of course

DWRC

ATC

descent

DSCNT

ATC

describe

DB

GEN

designate a friction value representing runway surface conditions (Greek letter)

MU

GEN

designated

DSGND

GEN

desire

DSR

GEN

destination

DESTN

GEN

destined

DSTND

ATC

detail

DTL

GEN

deteriorate

DTRT

NWS

determine

DTRM

GEN

develop

DVLP

GEN

deviation

DEV

ATC

deviation approved as requested

DAAR

ATC

dew point

DWPNT

NWS

dew point temperature

DP

ICAO

diagonal

DGNL

GEN

diameter

DIAM

GEN

difference in depth of modulation

DDM

GEN

differs

DFRS

GEN

difficult

DFCLT

GEN

diffuse

DFUS

GEN

diffuse

DIF

ICAO

digital altimeter setting indicator

DASI

GEN

Digital-Automatic Terminal Information Service D-ATIS ATC

digital barometer altimeter setting indicator

DBASI

GEN

Digital flight data recorder

DFDR

ICAO

diminish

DMSH

NWS

Diplomatic Telecommunications Service

DTS

GEN

direct

DCT

ICAO

direct

DRCT

GEN

direct altitude and identification readout equipment

DAIRE

GEN

Direct controller pilot communications

DCPC

ICAO

direct current

DC

GEN

direct readout infrared

DRIR

GEN

direct route

DR

GEN

direct user access terminal system

DUATS

GEN

direction

DRCTN

GEN

Directives Management Officer, FAA

DMO

GEN

director

DIR

GEN

disabled

DISABLD

GEN

discontinue

DISC

GEN

dispersal

DSPRL

GEN

displace

DSPLC

GEN

Displaced runway threshold

DTHR

ICAO

display

DSPL

GEN

disposition

DSPN

GEN

disregard

DSRGD

GEN

disseminate

DISEM

GEN

dissipate

DSIPT

NWS

distance

DIST

ICAO

distance

DSTC

GEN

distance from touchdown indicator

DFTI

GEN

distance measuring equipment

DME

ICAO

Distance Root Mean Square

DRMS

ATC

distant

DSNT

GEN

distant early warning

DEW

GEN

distant early warning identification zone

DEWIZ

GEN

distinguished visitors

DV

GEN

distort

DST

GEN

Distress Phase Code (Alerting Service)

DETRESFA

ATC

distribute

DISTR

GEN

district

DIST

GEN

district airport engineer

DAE

GEN

ditto

DO

GEN

diverge

DVRG

GEN

diversion

DVRSN

GEN

divert

DIV

ICAO

division

DIV

GEN

DME collocated with glide slope

DMEG

GEN

DME collocated with localizer

DMEL

GEN

DME collocated with VOR

DMEV

GEN

DME tactical air navigation with DME only commissioned

DMER

GEN

do all possible

DAP

GEN

do not pass to Air Defense radar

NOPAR

ATC

Do you intend to ask me for a series of bearings? Or I intend to ask you for a series of bearings

QDL

ICAO

docking

DCKG

ICAO

document

DCMT

GEN

doing business as

DBA

GEN

domestic

DOM

ICAO

domestic services (island operations)

DS

GEN

dominant

DMNT

GEN

doppler VHF omni directional radio range

DVOR

ICAO

double

DBL

GEN

double channel duplex

DCD

ICAO

double channel simplex

DCS

GEN

double sideband

DSB

ICAO

doubtful

DBTF

GEN

downdrafts

DWNDFTS

NWS

downslope

DNSLP

NWS

downstream

DNSTRM

NWS

downward vertical velocity

DVV

NWS

downwind

DNWND

ATC

drawing

DWG

GEN

drift

DRFT

NWS

drizzle

DRZL

NWS

drizzle

DZ

ICAO

dual tandem wheels

DTW

ICAO

dual wheels

DW

ICAO

duplex

DX

GEN

duplicate

DUPE

GEN

duration

DUR

ICAO

duration

DURN

GEN

during

DRG

ICAO

during

DURG

GEN

during climb

DURC

ATC

during descent

DURD

ATC

dust devils

PO

METAR

dust storm

DS

METAR

duststorm, sandstorm, rising dust or sand

SA

METAR

,

E

Definition

Contraction

Usage

each thousand foot level

ETFL

ATC

Early

ERY

GEN

early departure authorized

EDA

GEN

east or eastern longitude

E

ICAO

eastbound

EB

ICAO

eastbound

EBND

GEN

Eastern Region, FAA

AEA

GEN

Eastern Standard Time (time groups only)

E

NWS

eastern test range

ETR

ATC

east north east

ENE

ICAO

east northeastern (weather reports only)

ENERN

NWS

east northeastward (weather reports only)

ENEWD

NWS

east south east

ESE

ICAO

east southeastern (weather reports only)

ESERN

NWS

east southeastward (weather reports only)

ESEWD

NWS

effect

EFCT

GEN

effective

EFF

GEN

elapsed time

ETIM

ATC

electric

ELEC

GEN

electrical engineer

EENGR

GEN

electrician

ELECN

GEN

electronic counter measure mission

ECMSN

ATC

electronic counter measures

ECM

GEN

electronic equipment modification

EEM

GEN

electronic geographic coordinator navigation system

EGECON

GEN

electronic installation technician

EIT

GEN

electronic maintenance inspector

EMI

GEN

electronic maintenance technician

EMT

GEN

electronic mechanic technician

ELMT

GEN

electronic specialist

ECSP

GEN

electronic technician

ET

GEN

electronic unit

EU

GEN

electronic voice switching system

EVS

GEN

elevate or elevation

ELEV

ICAO

elliptical

ELIP

GEN

elongate

ELNGT

NWS

elsewhere

ELSW

GEN

embedded

EMBDD

NWS

embedded (in cloud layer)

EMBD

ICAO

emergency

EMERG

ICAO 

emergency gear

EG

GEN

emergency location beacon aircraft

ELBA

ICAO

emergency locator transmitter

ELT

GEN

emergency security control of air traffic

ESCAT

GEN

emergency use only

EUO

GEN

emission

EM

ICAO

en route

ENRT

GEN

en route automated radar tracking system

EARTS

GEN

en route communications

ECOM

GEN

en route communications

RCOM

GEN

en route metering

ERMG

ATC

en route penetration

EP

ATC

en route radar (broadband)

ERAD

GEN

en route secondary radar beacon (broadband)

ESEC

GEN

en route sequencing program

ESP

ATC

en route spacing program

ERSP

ATC

en route surveillance radar

RSR

ICAO

en route tracking automatic radar service

ETARS

ATC

encounter

ENCTR

GEN

encrypt for transmission only

EFTO

GEN

end exercise point

EEP

GEN

ending

ENDG

GEN

ending of precipitation (time in minutes) (weather reports only)

E

NWS

endurance

ENDCE

GEN

engine

ENG

ICAO

engineer

ENGR

GEN

Engineering and Manufacturing District Office

EMDO

GEN

engine generator

E/G

GEN

enhanced

ENHNCD

GEN

enhancement

ENHNCMNT

GEN

en route

ENR

ICAO

En route chart (followed by name/title)

ENRC

ICAO

enter control area

ECA

ATC

enter controlled airspace

ECAS

ATC

entered on duty

EOD

GEN

entering air defense identification zone

EADIZ

ATC

entire

ENTR

GEN

entire field available

EFA

GEN

environment meteorological support unit

EMSU

NWS

equatorial (air mass)

E

NWS

equipment

EQPT

ICAO

equipment

EQUIP

GEN

equipment certified

EQCRT

GEN

equivalent airspeed

EAS

ATC

Error (to be used in AFS as a procedure signal)

EEE

ICAO

especially

SPCLY

GEN

essential

ESNTL

GEN

establish

ESTAB

GEN

estimate or estimation

EST

ICAO

estimated departure clearance (time)

EDCT

ATC

estimated elapsed time

EET

ICAO

estimated information

ETI

ATC

estimated latitude

ELAT

GEN

estimated longitude

ELONG

GEN

estimated off block time

EOBT

ICAO

estimated time en route

ETE

GEN

estimated time of arrival

ETA

GEN

estimated time of departure

ETD

GEN

estimated time of penetration

ETP

ATC

estimated time over

ETOV

ATC

estimated time over significant point

ETO

ICAO

et cetera

ETC

GEN

Europe, Africa, and Middle East Office, FAA

AEU

GEN

Evacuation

EVAC

GEN

evaluate or evaluation

EVAL

GEN

Evening

EVE

GEN

Every

EV

ICAO

examination

EXAM

GEN

Except

EXC

ICAO

Except

EXCP

GEN

Except

XCP

NWS

except change departure to read

ECD

ATC

except change route to read

ECR

ATC

Exchange

EXCH

GEN

exchange and repair

E/R

GEN

Exclude

EXCLD

GEN

Exclusive

EXCLV

GEN

Execute

EXCT

GEN

Executive

EXEC

GEN

Exercise

EXER

ICAO

expanded position indicator

EPI

ATC

expanded quota flow

EXQF

ATC

expanded service volume

ESV

GEN

Expect

EXP

ICAO

Expect

EXPC

GEN

Expect

XPC

NWS

expect approach clearance

EACLN

ATC

expect approach clearance not later than

EACNL

ATC

expect departure clearance at

EDC

ATC

expect departure release at

EDR

ATC

expect further clearance at

EFC

ATC

expect further routing

EFR

ATC

expect higher altitude

EHA

ATC

expect vector to

EVT

ATC

expected approach time

EAT

ATC

expected operations forecast

EOF

NWS

expedite

EXPED

GEN

expedite delivery

EXDLVY

GEN

expedite delivery by telephone

EXPHO

GEN

expedite mail reply

EXREP

GEN

expedite shipment

EXSHI

GEN

explosive

XPLOS

GEN

express

EXPS

GEN

extend

EXTD

GEN

extension

EXTN

GEN

extensive

EXTSV

GEN

extra long range

ELR

ICAO

extra section

EXSEC

GEN

extrapolate

EXTRAP

NWS

extreme

EXTRM

NWS

extremely high frequency (30000 to 300000 MHz)

EHF

ICAO

,

F

Definition

Contraction

Usage

FAA Contract Flight Service Station

FCFSS

GEN

FAA Contract Weather Observing Station

FCWOS

GEN

FAA requirements

FAAR

GEN

facilitation of international air transport

FAL

ICAO

facilities

FAC

ICAO

facility

FAC

GEN

facility chief

FACF

GEN

facility coordination officer

FCO

GEN

facsimile

FAX

GEN

fahrenheit

F

GEN

fahrenheit

FAH

NWS

falling

FLG

NWS

familiar or familiarization

FAM

GEN

familiarization flight

FFLT

GEN

fan marker

FM

GEN

fan marker approach

FMAP

ATC

fan marker located with radio beacon

FMH

GEN

farther or further

FTHR

GEN

Fault Detection and Isolation

FDI

ATC

feathered

FTHRD

ATC

federal aid to airports program

FAAP

GEN

Federal Aviation Administration

FAA

GEN

Federal Aviation Regulations

FAR

GEN

Federal Communications Commission

FCC

GEN

Federal Telecommunications System

FTS

GEN

feet

FT

ICAO

feet per minute

FPM

GEN

field

FLD

ICAO

field condition

FICON

GEN

field condition report

FCRP

ATC

figure

FIG

GEN

filament

FIL

GEN

filed but impracticable to transmit

FIBI

NWS

filed flight plan

FPL

ICAO

filed flight plan in the air

AFIL

GEN

filed IFR flight plan

FIFP

ATC

filed VFR flight plan

FVFP

ATC

filing time

FT

GEN

filling

FILG

NWS

final approach

FA

ATC

final approach

FNA

ICAO

final approach fix

FAF

ICAO

final approach point

FAP

ICAO

fire warning

FWRNG

GEN

firing

FIRG

GEN

firing

FRNG

ICAO

first

FST

ICAO

first available

FIRAV

GEN

fixed federal monitoring network

FFMN

GEN

fixed pulse radar navigation aid

FPN

GEN

fixed wing special IFR

FW/SIFR

GEN

fixed wing special VFR

FW/SVFR

GEN

fixed base operator

FBO

GEN

fix radial distance

FRD

ATC

flares

FLR

ICAO

flash advisory

FL

NWS

flashing

FLG

ICAO

Fleet Area Controlled and Surveillance Facility

FACSFAC

ATC

Fleet Weather Central

FWC

NWS

flight

FLT

ICAO

flight check

FLTCK

ICAO

flight data

FDAT

GEN

Flight Data Center

FDC

GEN

flight data entry and printout

FDEP

ATC

flight data input/output

FDIO

ATC

flight data input/output repeater

FDIOR

ATC

flight data position

FLIDAP

GEN

Flight data processing system

FDPS

ICAO

flight engineer

FE

GEN

flight information (permanent)

FI/P

GEN

flight information (temporary)

FI/T

GEN

Flight Information Center

FIC

GEN

flight information publication

FLIP

GEN

Flight Information Region

FIR

GEN

Flight Information Region Boundary

FIRB

GEN

flight information service

FIS

GEN

flight inspection

F

GEN

Flight Inspection District Office

FIDO

GEN

Flight Inspection Field Office

FIFO

GEN

Flight Inspection Field Office High Altitude

FIFO H

GEN

flight inspection group

FIG

GEN

flight level

FL

GEN

Flight management system

FMS

ICAO

flight orders

FLTO

GEN

flight path deviation indicator

FPDI

GEN

flight plan

FP

GEN

flight plan

PLN

ICAO

flight plan area

FPA

ATC

flight plan not received

FPNO

GEN

flight plan route

FPR

GEN

flight progress board

FPB

ATC

flight schedule monitor

FSM

ATC

Flight Service Station

FSS

ICAO

Flight Standards District Office

FSDO

GEN

Flight Standards National Field Office

FSNFO

GEN

flight strip printer

FSP

GEN

flight watch area

FWA

GEN

flight watch control station

FWCS

GEN

flight watch outlet

FLTWO

GEN

flight watch point

FWP

GEN

flight watch specialist

FWS

GEN

flight watch unit

FWU

GEN

flood stage

FLDST

NWS

flood warning issued

FLWIS

NWS

florescan instrument landing system

FILS

GEN

flow control time of arrival

FCTA

ATC

flow management unit

FMU

ICAO

fluctuating

FLUC

ICAO

fluctuation

FLCTN

GEN

fluorescent runway lighting (floodlight system)

FLORL

GEN

flurry

FLRY

NWS

fly runway heading

FRH

ATC

fog

FG

METAR

fog dispersal operations

DENEB

ICAO

fog in vicinity

VCFG

METAR

fog partial

PRFG

METAR

fog patches

BCFG

NWS

follow

FLW

GEN

following amendment authorized effective

FAMAE

GEN

following transmitted as received (message handling)

FTAR

GEN

foot

FT

GEN

for an approach to

FAA

ATC

for further clearance

FFC

ATC

for possible reclearance

FPRC

ATC

for your information

FYI

GEN

forecast upper wind and temperature for aviation

WINTEM

ICAO

forecast

FCST

GEN

forecast upper wind and temperature at specified points

ARMET

GEN

forecast wind factor

FRWF

NWS

foreign object debris

FOD

GEN

forenoon

FORNN

NWS

form

FRM

GEN

format

FMT

GEN

formation

FRMN

GEN

forming

FRMG

NWS

forward

FWD

GEN

forward collect

FWDC

GEN

forward visibility (miles)

FV

ATC

forward visibility more than (miles)

MFV

ATC

freeze

FRZ

NWS

freezing drizzle

FZDZ

METAR

freezing fog

FZFG

METAR

freezing level

FRZLVL

NWS

freezing rain

FZRA

METAR

freezing rain information not available (weather reports only)

ZRNO

NWS

freezing rain sensor not available

FZRANO

METAR

frequency

FREQ

ICAO

frequency change approved

FCA

ATC

frequency division data link

FDDL

GEN

frequency management officer

FMO

GEN

frequent

FQT

GEN

frequent

FRQ

ICAO

Friday

FRI

ICAO

from

FM

ICAO

From (used to precede the call sign of the calling station)

DE

ICAO

from present position

FPP

ATC

front

FNT

NWS

frontal passage

FROPA

NWS

frontal surface

FROSFC

NWS

frontogenesis

FNTGNS

NWS

frontolysis

FNTLYS

NWS

frost

FRST

NWS

frozen

FRZN

NWS

FSS assumes control of tower frequencies and lights

FATFL

GEN

FSS assumes flight plan area and Service B

FAFAB

GEN

FSS guarding Service B

FGSB

GEN

FSS returns control of tower frequencies and lights

FRTFL

GEN

FSS returns flight plan area and Service B

FRFAB

GEN

FSS returns Service B

FRSB

GEN

fuel advisory

FA

ATC

fuel advisory departure

FAD

GEN

fuel on board

FOB

GEN

fuel remaining

FR

GEN

fuel supply exhausted

FEXHA

ATC

fuel supply unknown

FENKN

ATC

fuel supply until

FENTL

ATC

full performance level

FPL

ATC

full route clearance

FRC

GEN

full stop landing

FSL

ICAO

function

FNCTN

GEN

funnel cloud

FC

METAR

furnish

FURN

GEN

further particulars when available

FPWA

ATC

,

G

Definition

Contraction

Usage

gain time control

GTC

ATC

gallons

GALS

ATC

garble

GRBL

GEN

GBAS Landing System

GLS

ICAO

general

GEN

GEN

general aviation

GA

ICAO

General Aviation District Office

GADO

GEN

general notice

GENOT

GEN

General Safety District Office

GSDO

GEN

general safety inspector

GSI

GEN

General Services Administration

GSA

GEN

generator

GNTR

GEN

geographic

GEO

GEN

geographical reference

GEOREF

GEN

Geoid undulation

GUND

ICAO

get quick answer

GQA

GEN

gigahertz

GHZ

GEN

give better address

GBA

GEN

give better reference

GBR

GEN

giving

GVG

GEN

glaze icing

GICG

NWS

glide angle

GA

GEN

glide path

GP

ICAO

glide path angle GPA ICAO

glide slope

GS

GEN

glider

GLD

ICAO

glider

GLDR

GEN

global navigation satellite system

GLONASS

ICAO

global navigation satellite system (in general)

GNSS

ICAO

Global orbiting navigation satellite system

GLONASS

ICAO

global positioning system

GPS

ICAO

Go ahead, resume sending (to be used in AFS as a procedure signal)

GA

ICAO

government

GOVT

GEN

government bill of lading

GBL

GEN

government vehicle

GVH

GEN

Governor

GOV

GEN

GPS Integrity Channel

GIC

ATC

gradient

GRAD

NWS

gradual

GRADU

ICAO

gradual

GRDL

NWS

Grand Banks

GRBNKS

NWS

grass landing area

GRASS

ICAO

gravel

GRVL

ICAO

Great Circle

GTCL

GEN

Great Lakes

GRTLKS

NWS

Great Lakes Region, FAA

AGL

GEN

greater

GTR

GEN

green

G

ICAO

Greenwich Mean Time

GMT

GEN

Greenwich Mean Time

Z

GEN

grid point values of processed meteorological data

GRID

ICAO

gross weight

GWT

GEN

ground

GND

ICAO

ground-based augmentation system

GBAS

ICAO

ground check

GNDCK

ICAO

ground communication outlet

GCO

ATC

ground control

GC

GEN

ground control approach

GCA

ICAO

ground control intercept

GCI

GEN

ground delay program

GDPGM

ATC

ground delay program

GDP

ATC

ground earth station

GES

ICAO

ground fog

GNDFG

NWS

ground movement chart (followed by name/title)

GMC

ICAO

ground point of intercept

GPI

ATC

ground speed

GS

ATC

ground stop

GS

ATC

ground to air

G/A

ICAO

ground to air and air to ground

G/A/G

ICAO

ground visibility

GV

NWS

Gulf of Alaska

GLFALSK

NWS

Gulf of California

GLFCAL

NWS

Gulf of Mexico

GLFMEX

NWS

Gulf of St. Lawrence

GLFSTLAWR

NWS

gusts

GSTS

NWS

gusts reaching (knots) (weather reports only)

G

NWS

gusty

GSTY

NWS

,

H

Definition

Contraction

Usage

hail (greater than 3/4 )

GR

METAR

hail showers

SHGR

METAR

hail showers (small)

SHGS

METAR

hailstones

HLSTO

NWS

half

HLF

GEN

handoff point

HOP

ATC

handover word

HOW

ATC

hangar

HNGR

GEN

hard freeze

HDFRZ

NWS

Hawaiian Air Defense Division

HADD

GEN

Hawaiian Air Defense Identification Zone

HADIZ

GEN

Hawaiian Air National Guard

HANG

GEN

Hawaiian Defense Area

HADA

GEN

hazard

HAZ

GEN

hazard beacon

HBN

ICAO

hazardous area reporting service

HARS

ATC

hazardous inflight weather advisory service

HIWAS

GEN

hazardous material

HAZMAT

ICAO

haze

HZ

METAR

Head of State status

HEAD

ICAO

heading

HDG

ICAO

headquarters

HQ

GEN

headwind

HDWND

ATC

heater

HTR

GEN

heavy

HVY

ICAO

heavy (to qualify weather phenomena, e.g. XXRA heavy rain)

XX

ICAO

hectopascal

HPA

ICAO

height

HGT

ICAO

height above airport

HAA

GEN

height above landing

HAL

GEN

height above touchdown

HAT

GEN

helicopter

HEL

ICAO

helicopter operations

HOP

GEN

heliport

HELI

GEN

heliport HLP ICAO

here

ER

ICAO

here

HR

GEN

hertz

Hz

GEN

heterodyne

HTN

GEN

high

HI

NWS

high altitude balloon

HIBAL

GEN

high and very high frequency direction finding stations

HVDF

ICAO

high clouds visible

HCVIS

NWS

high density traffic airport

HDTA

GEN

high density traffic zones

HDATZ

ATC

high frequency

HF

GEN

high frequency direction finding station

HDF

ICAO

high index

HX

NWS

high intensity approach light system

HIALS

GEN

high intensity runway lights

HIRL

GEN

high level forecast

HIFOR

NWS

high voltage

HV

GEN

higher

HYR

ICAO

highest temperature

HITMP

NWS

highest temperature equaled for all time

HIEAT

NWS

highest temperature equaled for the month

HIEFM

NWS

highest temperature equaled so early

HIESE

NWS

highest temperature equaled so late

HIESL

NWS

highest temperature exceeded for all time

HIXAT

NWS

highest temperature exceeded for the month

HIXFM

NWS

highest temperature exceeded so early

HIXSE

NWS

highest temperature exceeded so late

HIXSL

NWS

highway

HWY

GEN

hilltop

HLTP

NWS

hold for release

HFR

ATC

holding

HLDG

ICAO

holding as previously instructed

HAPI

ATC

holding pattern

HP

GEN

holiday

HOL

GEN

homing beacon

HB

ATC

horizon

HRZN

GEN

Horizontal Dilution of Precision

HDOP

ATC

hospital aircraft

HOSP

ICAO

hour

HR

ICAO

household effects

HHE

GEN

how will arrival report be filed concerning

HIRIV

ATC

however

HWVR

GEN

Hudson Valley

HDSVLY

NWS

humanitarian mission

HUM

ICAO

hundred

HND

GEN

hurricane

HURCN

ICAO

hurricane report

HUREP

NWS

hydraulic

HYD

GEN

hydrographic

HYDRO

GEN

,

I

Definition

Contraction

Usage

ICAO Middle East/Asia Region

MID/ASIA

ATC

ice crystals (weather reports only)

IC

METAR

ice on runway

IR

NWS

ice pellet showers

SHPL

METAR

ice pellets

PL

METAR

icing

ICG

NWS

icing (PIREP only)

IC

ATC

icing in clouds

ICGIC

NWS

icing in clouds and precipitation

ICGICIP

NWS

icing in precipitation

ICGIP

NWS

identify or identifier  

ID

ICAO

identification beacon

IBN

ICAO

identification friend/foe

IFF

ICAO

identification

IDENT

ICAO 

if approach missed proceed

IFAMP

ATC

if authorized by ATC, DME may be used

IAATCD

ATC

if flight visibility becomes less than

IFVLS

ATC

if holding

IFHOL

ATC

if incorrect advise

IIA

GEN

if incorrect service direct

IISD

GEN

if instrument conditions encountered

IFINS

ATC

if not off

INOF

GEN

if not possible

INP

GEN

if unable

IFUN

GEN

if visibility remains

IFVR

ATC

IFR military training route

IR

GEN

ILS partial

ILSP

GEN

immediate

IMDT

NWS

immediate or immediately

IMT

GEN

immediately after passing

IMAP

ATC

immigration

IMG

ICAO

important

IMPT

GEN

impracticable

IMP

GEN

improve

IMPR

ICAO

improve

IPV

GEN

impulse

IMPL

GEN

in accordance with

IAW

GEN

in and out of clouds

IAO

ICAO

in clouds

INC

ICAO

in overcast

IOVC

NWS

in progress

INPR

ICAO

in RVR indicates visibility greater than highest reportable sensor value (e.g. P600FT)

P

METAR

in RVR indicates visibility less than lowest reportable sensor value (e.g. M600)

M

METAR

in temperature field means minus or below zero

M

METAR

in the vicinity of

INVOF

ATC

in valleys

VAL

ICAO

in VFR conditions

IVFRC

ATC

inadequate

INADQT

GEN

inbound

IBND

ATC

inbound

INBD

ICAO

inbound radial

IRAD

ATC

inch

IN

ICAO

include

INCL

GEN

inclusive

INCLV

GEN

incomplete

INCOMP

GEN

incorporated

INC

GEN

incorrect

INCOR

GEN

increase

INCR

GEN

indefinite

INDEF

GEN

independent sideband

ISB

ICAO

indicate

INDC

GEN

indicated air speed

IAS

ATC

Indication of a request

RQ

ICAO

individual development plan

IDP

GEN

individual flight plans from this point

IFPFP

ATC

industrial

INDUS

GEN

inertial navigation system

INS

ICAO

information

INFO

ICAO

information request

INREQ

GEN

initial approach

INA

ICAO

initial approach fix

IAF

ICAO

initial point

IP

ATC

initial point/H hour control line

IP/HHCL

ATC

initial training

INIT

GEN

inland

INLD

NWS

inland

LAN

ICAO

inland navigation facility

INF

GEN

inner marker

IM

ICAO

inoperative

INOP

ICAO 

inspect

INSP

GEN

instability

INSTBY

NWS

install

INSTL

GEN

instruct

INSTR

GEN

instructor pilot

IP

GEN

instrument

INST

GEN

instrument

INSTR

ICAO

instrument approach chart (followed by name/title)

IAC

ICAO

instrument approach procedure

IAP

ICAO

instrument flight rules

IFR

ICAO

instrument landing system

ILS

ICAO

instrument low approach

ILAS

ATC

instrument meteorological conditions

IMC

GEN

instruments authorized

INSTA

ATC

insufficient scheduled time available

INSUF

GEN

intend

INTD

GEN

intense

INTS

NWS

intensify

INTSFY

NWS

intensify or intensifying

INTSF

ICAO

intensity

INTST

ICAO

Intensity unknown (weather reports only)

IMI

ICAO

intensity unknown (weather reports only)

U

NWS

intentions

INTNS

GEN

Interagency Group on International Aviation

IGIA

GEN

intercept

INTCP

GEN

intercontinental

INTCNTL

GEN

Interdepartmental Radio Advisory Committee

IRAC

GEN

Interface Control Document

ICD

ATC

Interface Revision Notices

IRN

ATC

interfacility data

IDAT

GEN

interference

INTFC

GEN

interim standard microwave landing system

ISMLS

GEN

interior

INTR

NWS

intermediate

INTMD

GEN

intermediate approach fix

IF

ICAO

intermediate fix

IF

GEN

intermittent

INTER

ICAO

intermittent

INTMT

GEN

intermittent instruments

I/IFR

ATC

Inter Mountain Region

INTRMTRGN

NWS

international

INTL

ICAO

International Administrative Aeronautical Radio Conference

IAARC

GEN

International Aeronautical Telecommunications Switching Center

IATSC

GEN

International Air Transport Association

IATA

GEN

International Civil Aviation Organization

ICAO

GEN

international dateline

DTLN

NWS

International Field Office

IFO

GEN

International Flight Information Manual

IFIM

GEN

International Flight Service Station

IFSS

GEN

international general aviation

IGA

ICAO

international standard atmosphere

ISA

ICAO

International Telecommunications Union

ITU

GEN

interphone

IFO

GEN

interphone (service F) not operative

IFONO

GEN

interphone (service F) resumed operation

IFORO

GEN

interrogation sign

IMF

GEN

interrogator

INTRG

ICAO

interrupt

INTRP

GEN

interruption of air traffic services

INATS

GEN

intersection

INT

ICAO

intersection

INTXN

GEN

intersection of air routes

IAR

ICAO

interstate

INSTA

GEN

interval

INTVL

GEN

intervals between aircraft in stream type formation

IBASF

ATC

inversion

INVRN

NWS

investigate

INVES

GEN

investigate and report

INVSTAR

GEN

irregular

IREG

GEN

island

IS

GEN

Island Manager

ISMGR

GEN

isolate

ISOL

GEN

issue time check

ITCK

ATC

itinerant

ITNRNT

GEN

itinerary

ITRY

GEN

,

J

Definition

Contraction

Usage

jet approach landing charts

JAL

GEN

jet assisted take off

JATO

ATC

jet penetration

JP

ATC

jet penetration approach

JPAP

ATC

jet runway barrier

J BAR

ATC

jet stream

JTST

ICAO

jet stream

JTSTR

NWS

jet terminal area

Z

ATC

join airways

JAWYS

ATC

journeyman

JOUR

GEN

junction

JCTN

GEN

,

K

Definition

Contraction

Usage

keep this office advised

KEPOA

GEN

killing frost

KFRST

NWS

kilocycles

KC

GEN

kilogram

KG

GEN

kilohertz

KHZ

GEN

kilometers

KM

GEN

kilometers per hour

KMH

ICAO

kilopascal

KPA

ICAO

kilowatt

KW

GEN

knots

KT

GEN

,

L

Definition

Contraction

Usage

Laboratory

LAB

GEN

labrador

LABRDR

NWS

lake

LK

NWS

lake reporting service

LRS

GEN

laminar flow control

LFC

GEN

land

LND

GEN

land lines communications facilities

LICOF

GEN

landing

LDG

ICAO

landing

LNDG

GEN

landing direction indicator

LDI

ICAO

landing distance available

LDA

ICAO

landing rights airport

LRA

GEN

landing traffic

LTFC

ATC

landline

LL

GEN

landline teletypewriter

LTT

ICAO

large

LRG

GEN

last radio contact

LARCT

ATC

later

LTR

GEN

lateral navigation (from TERPS A1)

LNAV

GEN

latitude

LAT

ICAO

latter

LTTR

GEN

layer or layered or layers

LYR

NWS

lead in lighting system

LDIN

GEN

leased Service A/B system

LABS

ATC

leave or leaving

LVE

ICAO

leaving

LV

GEN

leaving

LVG

ATC

left

L

ICAO

left base

LB

ATC

left side

LS

ATC

left traffic pattern

LP

ATC

length

LEN

ICAO

letter

LTR

GEN

letter follows

LETFO

GEN

letter of agreement

LOA

GEN

level

LVL

ATC

level off

LVLOF

ATC

liaison officer

LO

GEN

lift

LFT

NWS

light or lighting

LGT

ICAO

light and variable

LTAV

GEN

light and variable

LV

ICAO

light intensity high

LIH

ICAO

light intensity low

LIL

ICAO

light intensity medium

LIM

ICAO

lighted

LGTD

ICAO

lightning

LTNG

NWS

lightning cloud to air

LTGCA

NWS

lightning cloud to cloud

LTGCC

NWS

lightning cloud to cloud, cloud to ground

LTGCCCG

NWS

lightning cloud to ground

LTGCG

NWS

lightning cloud to water

LTGCW

NWS

lightning in clouds

LTGIC

NWS

like type

LKTYP

ATC

likely

LKLY

GEN

limit

LMT

GEN

limited

LTD

ICAO

Limited Aviation Weather Reporting Station

LAWRS

GEN

line

LN

GEN

line of position

LOP

GEN

line squall

LSQ

ICAO

linear polarization

LP

ATC

linearity

LIN

GEN

liquid propane

LP

GEN

little

LTL

GEN

little change

LTLCG

NWS

little change in temperature

LCTMP

NWS

local airport advisory

LAA

GEN

local airport deicing plan

LADP

ATC

Local Area Augmentation System

LAAS

ATC

local control

LC

GEN

local coordinator

LOCOR

GEN

Local Mean Time

LMT

ICAO

local or locally

LCL

GEN

local standard time

LST

GEN

local training flight

LTF

ATC

localizer

LOC

ICAO

localizer (not associated with ILS)

LLZ

ICAO

Localizer performance without
vertical guidance

LP

GEN

Localizer performance with vertical guidance

LPV

ICAO

localizer type directional aid

LDA

ATC

locally

LCA

ICAO

locate

LCT

GEN

location (PIREP only)

OV

ATC

locator

L

ICAO

locator middle

LM

ICAO

logical acknowledgement

LAM

ICAO

logistics

L

GEN

long distance

LD

GEN

long distance navigation

LODISNAV

GEN

long range

LGRNG

NWS

long range

LRG

GEN

long range accuracy

LORAC

GEN

long range air navigation system

LORAN

GEN

long range VHF/UHF communications

LRCOM

GEN

long wave

LGWV

GEN

longitude

LONG

ICAO

longitudinal

LONGL

GEN

loose snow on runway

LSR

NWS

low altitude arrival/departure routing

LAADR

ATC

low altitude bombing system

LABS

GEN

low approach

LA

ATC

low drifting

DR

METAR

low drifting dust

DRDU

METAR

low drifting sand

DRSA

METAR

low drifting snow

DRSN

METAR

low frequency

LF

GEN

low frequency intersection

LFNT

GEN

low frequency radio range

LFR

GEN

low IFR (weather reports only)

LIFR

NWS

low index

LX

NWS

low intensity runway edge lights

LIRL

GEN

low level wind shear

LLWS

GEN

low level wind shear alert system

LLWAS

GEN

low or medium frequency long range navigational aid

CONSOLAN

GEN

low or medium frequency radio range stations

RR

GEN

low/medium frequency

L/MF

GEN

low visibility operations

LVO

GEN

lower

LWR

GEN

lowest temperature

LOTMP

NWS

lowest temperature equaled for all time

LOEAT

NWS

lowest temperature equaled for the month

LOEFM

NWS

lowest temperature equaled so early

LOESE

NWS

lowest temperature equaled so late

LOESL

NWS

lowest temperature exceeded for all time

LOXAT

NWS

lowest temperature exceeded for the month

LOXFM

NWS

lowest temperature exceeded so early

LOXSE

NWS

lowest temperature exceeded so late

LOXSL

NWS

,

M

Definition

Contraction

Usage

Mach number

M

GEN

MACH Number (speed ratio to speed of sound)

MACH

ATC

Mackay Radio and Telegraph Company

MACKAY

GEN

magnetic

MAG

GEN

magnetic bearing

QDR

ICAO

magnetic heading

MHDG

GEN

magnetic heading

QDM

ICAO

magnetic orientation of runway

QFU

ICAO

magnetic variation

VAR

ICAO

main meteorological office

MMO

NWS

mainland

MNLD

NWS

mainly

MNLY

GEN

maintain

MNTN

ICAO

maintain a position VFR and advise

MPVA

ATC

maintain at least (altitude)

MAL

ATC

maintain flight level

MFL

ATC

maintain Mach

MMACH

ATC

maintain VFR

MVFR

ATC

maintain visual separation

MVSP

ATC

maintain well to right of course

MWRC

ATC

maintaining visual flight (Special VFR)

VF

ATC

maintenance

MAINT

ICAO

maintenance assumes monitor

MAM

GEN

maintenance check

MCK

GEN

maintenance returns monitor

MRM

GEN

make altitude changes VFR

MACVFR

ATC

make check turn

MKCT

ATC

make descent from

MDFR

ATC

make good a magnetic track of (degrees)

MGMT

ATC

make good a track of (degrees)

MGAT

ATC

management

MGMT

GEN

manager

MGR

GEN

maneuver

MNVR

GEN

Manitoba

MAN

NWS

manual

MAN

GEN

manual A1 simplex

MAS

ICAO

manual amendment

MANAM

GEN

manual of operations

MANOP

GEN

manufacturing inspector

MI

GEN

map analysis

MA

NWS

marginal

MRGL

NWS

marginal VFR

MVFR

NWS

Marine Corps Air Station

MCAS

GEN

Marine Corps Air Station (Helicopter)

MCAS(H)

GEN

maritime

MRTM

NWS

maritime (air mass)

M

NWS

marked

MKD

GEN

marker

MKR

GEN

marker beacon

MB

GEN

marker radio beacon

MKR

ICAO

marking

MRKG

GEN

Master Control Station

MCS

ATC

master flight plan on file

MFPOF

ATC

material

MTRL

GEN

maximum

MAX

GEN

maximum authorized (IFR) altitude

MAA

GEN

maximum usable altitude

MUA

GEN

maximum usable frequency

MUF

GEN

meaconing, intrusion, jamming, interference

MIJI

ATC

mean sea level

MSL

ICAO

mechanic

MECH

GEN

mechanical reliability report

MRR

GEN

medical

MED

GEN

medical emergency evacuation

MEDEVAC

ICAO

medium

MED

GEN

medium and high frequency direction finding station (same location)

MHDF

ICAO

medium and very high frequency direction finding station (same location)

MVDF

ICAO

medium frequency

MF

GEN

medium frequency direction finding station

MDF

ICAO

medium high and very high frequency direction finding station (same location)

MHVDF

ICAO

medium intensity approach lighting system

MALS

GEN

medium intensity approach lighting system with runway alignment indicator lights

MALSR

GEN

medium intensity approach lighting system with sequenced flashers

MALSF

GEN

medium intensity runway edge lights

MIRL

GEN

medium range

MRG

GEN

megahertz

MHZ

ICAO

melting level

MLTLVL

NWS

memorandum of agreement

MOA

GEN

memorial

MEML

GEN

merging

MEGG

NWS

Merit Promotion Program

MPP

GEN

message

MSG

ICAO

Message (transmission identification) has been misrouted

MSR

ICAO

message center

MSGCTR

GEN

meteorological

MET

GEN

Meteorological Aeronautical Presentation System

MAPS

GEN

meteorological information for aircraft in flight

VOLMET

ICAO

meteorological officer

METOF

GEN

Meteorological Operational Telecommunications Network Europe

MOTNE

ICAO

Meteorological Watch Office

MWO

ICAO

meter fix time

MFXT

ATC

meters per second

MPS

ICAO

metres (preceded by figures)

M

ICAO

metric units

MTU

ICAO

metropolitan

METRO

GEN

Mexico

MEX

NWS

microburst

MBST

ICAO

microwave landing system

MLS

GEN

Mid Canada Identification Zone

MIDIZ

GEN

middle

MID

GEN

middle marker

MM

ICAO  

midnight

MIDN

NWS

midpoint

MIDPT

GEN

mid point (related to RVR)

MID

ICAO

Mike Monroney Aeronautical Center, FAA

AAC

GEN

mile

MI

GEN

miles in trail

MIT

ATC

miles per hour

MPH

GEN

military

MIL

ICAO 

Military Airlift Command

MAC

GEN

military alert system

MAS

GEN

military assumes responsibility for separation of aircraft

MARSA

GEN

military, customs, or police services

STATE

ICAO

military flight service

MFS

GEN

military height finder radar

MHFR

GEN

military operations area

MOA

ICAO  

Military Radar Unit

MRU

GEN

military training route

MTR

GEN

millibars

MB

GEN

millimeter

MM

GEN

millivolt

MV

GEN

mimeographic notice

MIMNO

GEN

minimum

MNM

ICAO

minimum altitude at glide slope intersection inbound

MAGSI

GEN

minimum altitude over facility on final approach course

MAFAP

ATC

minimum crossing altitude

MCA

ICAO

minimum descent altitude

MDA

ICAO  

minimum descent height

MDH

ICAO

minimum en route altitude

MEA

ICAO  

minimum eye height over threshold

MEHT

ICAO

minimum fuel on board

MFOB

ATC

minimum holding altitude

MHA

GEN

minimum interval take off

MITO

ATC

minimum navigation performance specification

MNPS

ATC

minimum navigation performance specification airspace

MNPSA

ATC

minimum obstacle clearance (required)

MOC

ICAO

minimum obstruction clearance altitude

MOCA

ICAO

Minimum operational performance standards

MOPS

ICAO

minimum reception altitude

MRA

GEN

minimum requirements specified

MIREQ

GEN

minimum safe altitude warning

MSAW

GEN

minimum safe/sector altitude

MSA

GEN

minimum terrain clearance altitude

MTCA

GEN

minimum vector altitude

MVA

GEN

minimum when control zone effective

MCZNE

GEN

Ministry of Transport (Canada)

MOT

GEN

minus

MS

NWS

minute

MIN

ICAO  

minutes in trail

MINIT

ATC

miscellaneous

MISC

GEN

missed approach point

MAP

GEN

missed approach point

MAPT

ICAO

missile

MISL

GEN

missing

MISG

GEN

missing (weather reports only)

M

NWS

Missing (transmission identification)

MIS

ICAO

mist

BR

METAR

mixed

MXD

NWS

moderate

MDT

GEN

moderate

MOD

GEN

moderate or greater

MOGR

NWS

modernization

MDZN

GEN

modernize

MDZ

GEN

modernized weather teletypewriter communications system

MWTCS

GEN

modify

MDFY

GEN

modulate or modulation or modulator

MOD

GEN

modulated continuous wave

MCW

ICAO

Mohawk Valley

MHKVLY

NWS

moisture

MSTR

NWS

momentary

MTRY

GEN

Monday

MON

ICAO

monitor,monitored, or monitoring

MNT

ICAO

monitor

MONTR

NWS

monitor out of service

MONOS

GEN

monitor resumed normal operation

MONOK

GEN

monitor station reports

MOREPS

GEN

Monopulse secondary surveillance radar

MSSR

ICAO

morning

MRNG

NWS

mostly

MSTLY

NWS

mountain

MT

ICAO

mountain

MTN

NWS

Mountain Standard Time (time groups only)

M

NWS

mountain wave

MTW

ICAO

Move, or moving, or movement

MOV

ICAO

moving target indicator

MTI

ATC

multi object phase tracking and ranging

MOPTAR

GEN

multiple

MULT

GEN

municipal

MUNI

GEN

municipal airport

MARPT

GEN

must ride company material

RIMAT

GEN

,

N

Definition

Contraction

Usage

name to

NTO

GEN

Narrow

NRW

GEN

National

NATL

GEN

National

NTL

ICAO

National Aeronautics and Space Administration

NASA

GEN

National Air Traffic Controllers Association

NATCA

ATC

National Air Transport Coordinating Committee

NATCC

GEN

National Aircraft Noise Abatement Council

NANAC

GEN

National Airport System Plan

NASP

GEN

National Airspace Data Interchange Network

NADIN

GEN

National Airspace Performance Reporting System

NAPRS

ATC

National Airspace System

NAS

GEN

National Airspace System
Interfacility Communications System

NICS

GEN

National Airways System Engineering office

NASEO

GEN

National AIS system centre

NASC

ICAO

National Association of Air Traffic Control Specialists

NAATS

GEN

National Aviation Facilities Experimental Center

NAFEC

GEN

national beacon code allocation plan

NBCAP

GEN

National Climatic Data Center

NCDC

GEN

National Communications Center

NATCOM

GEN

national communications schedule

NACOS

GEN

National Communications System

NCS

GEN

national environmental satellite service

NESS

GEN

National Flight Data Digest

NFDD

GEN

National Guard

NG

GEN

National Meteorological Center

NMC

GEN

National Ocean Service

NOS

GEN

National Oceanic and Atmospheric Administration

NOAA

GEN

National Severe Storm Forecast Center

NSSFC

GEN

National Track Analysis Program

NTAP

ATC

National Transportation Safety Board

NTSB

GEN

National Weather Service

NWS

GEN

National Weather Service Support Facility

WSSF

GEN

National Weather Service Support Unit

WSSU

GEN

nautical mile

NM

ICAO 

nautical mile radius

NMR

GEN

Naval Air Facility

NAF

GEN

Naval Air Station

NAS

GEN

Naval Auxiliary Air Station

NAAS

GEN

Naval Oceanographic Meteorological Automatic Device

NOMAD

GEN

Naval Reserve Air Base

NRAB

GEN

Naval Weather Service Office

NWSO

GEN

navigation

NAV

ICAO

Navigation, ATC, and Collision Avoidance System

NATCAS

GEN

navigational aid

NAVAID

GEN

Navy Liaison Officer

NAVLO

GEN

Navy Representative to the FAA

NAVREP

GEN

NDB and DME (collocated)

NDB/DME

GEN

near

NR

GEN

near or over large towns

CIT

ICAO

necessary

NEC

GEN

negative

NEG

GEN

negative replies not required

NONEG

GEN

negative vorticity advection

NVA

NWS

neighborhood

NBRHD

GEN

New Brunswick

NB

NWS

New England

NEW ENG

NWS

New England Region, FAA

ANE

GEN

Newfoundland

NFLD

NWS

next

NXT

GEN

night

NGT

ICAO

night frequency

NFQ

GEN

nimbostratus

NS

NWS

No (negative)

NO

ICAO

no action necessary

NOAC

GEN

no additional traffic reported

NATR

ATC

no arrival report

NORIV

ATC

no change

NC

GEN

no change in estimates

NCE

ATC

no change in weather

NCWX

NWS

no delay expected

NDE

ATC

no essential traffic reported

NETR

ATC

no filing time

NFT

GEN

no further clearance required

NEF

ATC

no further information

NOFIN

GEN

no information

NOIFN

GEN

no layers

NL

NWS

no middle name

NMN

GEN

no parallel traffic

NPRL

ATC

no pilot balloon observation due to high, or gusty, surface wind

PIWI

NWS

no pilot balloon observation due to snow

PISO

NWS

no pilot balloon observation due to unfavorable sea conditions

PISE

NWS

no pilot balloon observation will be filed next collection unless weather changes significantly

NORPI

NWS

no procedure turn required

NOPT

GEN

no radio

NORDO

GEN

no radio contact

NORAC

ATC

no RAWIN obs., communications out

RACO

NWS

no RAWIN obs., high and gusty winds

RAWI

NWS

no RAWIN obs., no balloons available

RABA

NWS

no RAWIN obs., no gas available

RAHE

NWS

no RAWIN obs., unfavorable weather

RAWE

NWS

no record

NOREC

GEN

no record of destination

NRD

GEN

no reply heard

NRH

ICAO

no reply received

NORR

GEN

no report

NOREP

GEN

no restrictions

NORST

GEN

no significant change

NOSIG

ICAO

no significant cloud

NSC

ICAO

no significant weather

NSW

METAR

no small craft or storm warning are being displayed

NSCSWD

NWS

no special observations taken (weather reports only)

NOSPL

NWS

no specific working hours

HX

ICAO

no traffic reported

NTRP

ATC

no transgression zone

NTZ

ATC

No transgression zone

NTZ

ICAO

no trouble found

NTFND

GEN

noise abatement test system

NATS

GEN

nondirectional radio beacon

NDB

ICAO 

none

NIL

GEN

nonpersistent

NPRS

NWS

nonprecision instrument

NPI

GEN

nonrevenue

NRV

GEN

non-RVSM capable flight

NONRVSM

ICAO

non-standard NSTD GEN

Nonstandard C/A Code

NSC

ATC

nonstandard holding pattern

NSP

GEN

nonstop

NSTP

GEN

NORAD Region Operations Control Center

ROCC

GEN

NORAD Sector Operations Control Center

SOCC

GEN

normal

NML

GEN