NOTAM (Notice to Airmen) Acronyms

A

A Absolute
A Alaskan Standard Time
A Amber
A Arctic (air mass)
A/A Air to Air
A/C Approach Control
A/G Air to Ground
A/H Already Had
AAC Alaskan Air Command
AAD Assigned Altitude Deviation
AADC Approach and Departure Control
AAF Army Air Field
AAITVL Arrival Aircraft Interval
AAL Above Aerodrome Level
AAL Alaskan Region
AAP Advise if Able to Proceed
AAR Airport Arrival Rate
AARTE Airport Acceptance Rate
AATM At All Times
AAWF Auxiliary Aviation Weather Facility
AAWTA Advise at What Time Able
AB Airborne
ABBR Abbreviate
ABCST Automatic Broadcast
ABD Aboard
ABI Advance Boundary Information
ABLCHG Airborne Launching
ABM Abeam
ABN Aerodrome Beacon
ABND Abandon
ABNDT Abundant
ABNML Abnormal
ABT About
ABV Above
AC Advisory Circular
AC Altocumulus
AC Assistant Chief
ACA Artic Control Area
ACARS Aircraft Communication Addressing and Reporting System
ACAS Airborne Collision Avoidance System
ACC Altocumulus Castellanus
ACC Area Control Center
ACCID Notification of Aircraft Accident
ACCT Account
ACCUM Accumulate
ACDNT Accident
ACDO Air Carrier District Office
ACE Central Region
ACES Access
ACFT Aircraft
ACID Aircraft Identification
ACK Acknowledge
ACL Altimeter Check Location
ACLD Above Clouds
ACLS Automatic Carrier Landing System
ACLT Accelerate
ACM Air combat maneuvers
ACN Aircraft Classification Number
ACN All Concerned Notified
ACNOT Accident Notice
ACP Acceptance (message type designator)
ACP Area Command Post
ACPT Accept
ACPY Accompany
ACR Air Carrier
ACRBT Acrobatic
ACRS Across
ACSL Standing Lenticular Altocumulus
ACT Active or Activated or Activity
ACT Air Combat Training
ACT Technical Center
ACTG Acting
ACTV Active
ACTVT Activate
ACW Aircraft Control and Warning
ACYC Anticyclonic
AD Aerodrome
ADA Advisory Area
ADAP Airport Development Aid Program
ADC Aerodrome Chart
ADCF Air Defense Control Facility
ADCON Advise or issue instructions to all concerned
ADCUS Advise Customs
ADDN Addition
ADE Air Defense Emergency
ADF Automatic Direction Finder
ADFAP Automatic Direction Finder Approach
ADIZ Air Defense Identification Zone
ADJ Adjacent
ADL Aggregate Demand List
ADLO Air Defense Liaison Officer
ADLY Arrival Delay
ADMAP Advise by Air Mail as Soon as Possible
ADMIN Administration
ADMIR Administrator
ADMIS Aircraft Departing at (number of minutes) Interval
ADMIV Administrative
ADNL TFC Additional Traffic
ADNOK Advise if not correct
ADO Aerodrome Office (specify service)
ADO Airport District Office
ADP Automatic Data Processing
ADPE Automatic Data Processing Equipment
ADPS Automatic Data Processing Systems
ADQT Adequate
ADR Advisory Route
ADR Airport Departure Rate
ADRDE Advise Reason for Delay
ADRNDCK Adirondack
ADRT Alternate Departure Route
ADS Address
ADS Air Defense Sector
ADS Automatic Dependent Surveillance
ADSPN Advise Disposition
ADSU Automatic Dependent Surveillance Unit
ADV Advise
ADVALT Allotment Advice
ADVC Advice
ADVCTN Advection
ADVN Advance
ADVY Advisory
ADVZY Advisory
ADW Air Defense Warning
ADZ Advise
ADZAR Advise Arrival
ADZI Advise Intentions
ADZOF Advise This Office
ADZY Advisory
AEA Eastern Region
AEM Aircraft and Engine Mechanic
AENG Airways Engineer
AER Approach End Runway
AERO Aeronautical
AES Aircraft Earth Station
AEU Europe Africa and Middle East Office
AEVAC Air Evacuation
AEW Airborne Early Warning
AFB Air Force Base
AFC Area Forecast Center
AFCT Affect
AFD Airport Facility Directory
AFDK After Dark
AFIL Filed Flight Plan in the Air
AFIO Authorization for Interceptor Operations
AFIRM Affirmative
AFIS Aerodrome Flight Information Service
AFJ Air Force Jet
AFM Affirmative
AFNEA Air Force NOTAM Exchange Area
AFNEO Air Force NOTAM Exchange Office
AFOVRN Air Force Overrun (1000ft standard approach lighting system)
AFREP Air Force Representative
AFRT Air Freight
AFS Aeronautical Fixed Service
AFSS Automated Flight Service Station
AFT After
AFTN Aeronautical Fixed Telecommunications Network
AFTN Afternoon
AG Air Ground
AGA Aerodromes Air Routes and Ground Aids
AGACS Automatic Ground Air Ground Communication System
A-GEAR Arresting Gear
AGL Above Ground Level
AGL Great Lakes Region
AGN Again
AGR Agree
AGRMT Agreement
AHD Ahead
AI Arrival Approved Request for IFR Flight
AIA Advise if Able
AIATSC All International Air Traffic Switching Centers
AIC Aeronautical Information Circular
AID Airport Information Desk
AIDC Air Traffic services Inter facility Data Communication
AIFP Activate IFR Flight Plan
AILS Automatic Instrument Landing System
AIM Airman’s Information Manual
AIP Aeronautical Information Publication
AIRAC Aeronautical Information Regulation and Control
AIRCOMNET Air Force Communications Network
AIREP Air Report
AIRFL Air Refueling
AIRMET Airmen's Meteorological Information
AIROPNET Air Operations Network
AIS Aeronautical Information Service
AIS Aeronautical Information Specialist
AIS Airport in sight
AL All Field Offices and Personnel
AL Annual Leave
AL/At Least (altitude)
ALA Alighting Area
ALACFO All Air Carrier Field Offices
ALADLO All Air Defense Liaison Officers in Service Area
ALAFFO All Technical Operations
ALANO All Accident Notice Offices
ALARTC All Air Route Traffic Control Centers in Service Area
ALAT All Air Traffic Service Personnel in Service Area
ALATAS All Air Traffic (area) Supervisors in Service Area
ALATF All Air Traffic Field Facilities
ALATFO All Air Traffic Field Offices
ALCKT All Offices Having Send−receive Teletypewriter Service on Circuit
ALCS/C All Air Traffic Combined Station/ Centers in Service Area
ALCS/T All Air Traffic Combined Station/ Towers in Service Area
ALCT Attempt to Locate
ALDA Air Line Dispatchers Association
ALERFA Alert Phase Code (alerting service)
ALF Aloft
ALFAB All Offices on NADIN
ALFSFO All Flight Standards Field Offices
ALFSS All Flight Service Stations in Service Area
ALG Along
ALGHNY Allegheny
ALIATSC All International Aeronautical Telecommunication Switching Centers
ALIFO All International Field Offices
ALIFSS All International Flight Service Stations in Service Area
ALNMT Alignment
ALNOT Alert Notice
ALP Airport Layout Plan
ALPA Air Line Pilots Association
ALQDS All Quadrants
ALR Alerting
ALRAFAC All Radar Facilities in Service Area
ALRGN All Regional Service Area Offices
ALS Approach Light System
ALSEC All Sectors
ALSF Approach Lighting System With Sequenced Flashing Lights
ALSF1 Approach Lighting System With Sequenced Flashers Cat 1
ALSF-1 Approach Lighting System With Sequenced Flashers Cat 1
ALSF2 Approach Lighting System With Sequenced Flashers Cat 2
ALSF-2 Approach Lighting System With Sequenced Flashers Cat 2
ALSFI Approach Lighting System With Sequenced Flashers Cat 1
ALSF-I Approach Lighting System With Sequenced Flashers Cat 1
ALFSII Approach Lighting System With Sequenced Flashers Cat 2
ALSF-II Approach Lighting System With Sequenced Flashers Cat 2
ALSTG Altimeter Setting
ALT Altitude
ALTA Alberta
ALTM Altimeter
ALTN Alternate
ALTPT Alternate Airport
ALTRV Altitude Reservation
ALTWR All Towers in Service Area
ALUTN Aleutian
ALWF Actual Wind Factor
AM Ante Meridiem
AMA Area Minimum Altitude
AMB Ambiguity
AMC Air Mobility Command
AMC Mike Monroney Aeronautical Center
AMCL Amended Clearance
AMD Amend
AMD Amended Forecast
AMDT Amendment
AMECH Account Mechanical
AMGR Airport Manager
AMIS Aircraft Movement Information Services
AMOS Automatic Meteorological Observing System
AMP Amplifier or Amplify
AMPLTD Amplitude
AMRF Amended Route of Flight
AMS Aeronautical Mobile Service
AMS Air Mass
AMS American Meteorological Society
AMSL Above Mean Sea Level
AMSS Aeronautical Mobile Satellite Service
AMT Amount
AMVER Automated Mutual Assistance Vessel Rescue System
ANC Aeronautical Chart
ANCPT Anticipate
ANCS Aeronautical Navigation Chart Small Scale
ANE New England Region
ANF Air Navigation Facility
ANG Air National Guard
ANLYS Analysis
ANM Northwest Mountain Region
ANMS Automatic Network Management System
ANNC Announce
ANR Advanced Navigation Routes
ANRA Air Navigation Radio Aids
ANS Answer
ANT Antenna
AO1 ASOS Automated Observation Without Precipitation Discriminator (rain/snow)
AO2 ASOS Automated Observation With Precipitation Discriminator (rain/ snow)
AOA At or Above
AOAF At or After
AOB At or Below
AOBF At or Before
AOC Aerodrome Obstacle Chart
AOC Airport Operating Certificate
AOCP Aircraft Out of Commission for Parts
AOE Airport of Entry
AOPA Aircraft Owners and Pilots Association
AP Airport
AP Anomalous Propagation
APAP Approach Path Alignment Panel
APAP This list is copywritten and belongs to proairpilot
APAPI Abbreviated Precision Approach Path Indicator
APC Area Positive Control
APCH Approach
APDC Aircraft parking/docking chart
APL Airport Lights
APLCN Appalachian
APN Apron
APNT Appoint
APP Approach Control
APP Approach Control Office
APPA Advise Present Position and Altitude
APPR Appear
APR Airports Program Report
APREQ Approval Request
APRNT Apparent
APROP Appropriate
APRX Approximate
APS Airborne Pulse Search Radar
APSG After Passing
APV Approve
APVL Approval
AR Atlantic Route
ARAC Area Airports Checked
ARAC Army Radar Approach Control Facility
ARAD Altitude Radial
ARB Air Reserve Base
ARC Area chart
ARCP Air Refueling Control Point
AREP Air Refueling Egress Point
AREX Air Refueling Exit
ARFF Aircraft Rescue and Fire Fighting
ARFFOK Airport Rescue and Fire Fighting Alarm Checked
ARFOR Area Forecast
ARINC Aeronautical Radio Incorporated
ARIP Air Refueling Initial Point
ARL Aerial
ARLO Army Liaison Officer
ARMET Forecast upper wind and temperature at specified points
ARML Airmail
ARND Around
ARNG Arrange
ARNOT Area Notice
ARO Air Traffic Services Reporting Office
ARO Airport Reservations Office
ARP Aerodrome Reference Point
ARP Airport Reference Point
ARP Airport Reservation Position
ARP Air Report
ARPT Airport
ARQ Automatic Error Correction Equipment
ARR Arrival or Arrive
ARS Air Rescue Service (USAF)
ARS Special Air Report
ARSA Airport Radar Service Area
ARSR Air Route Surveillance Radar
ARST Arrest
ARTC Air Route Traffic Control
ARTCC Air Route Traffic Control Center
ARTS Automated Radar Terminal Systems
ARU Airborne Radar Unit
ARU Airspace Reservation Unit
ARUNK Arrival Unknown
AS Altostratus
AS/R Automatic Send/Receive
ASAP As Soon As Possible
ASC Ascent to
ASCU Automatic Scanning Control Unit
ASD Airspace Docket
ASDA Accelerate Stop Distance Available
ASDE Airport Surface Detection Equipment
ASE Altimetry System Error
ASGN Assign
ASI Altimeter Setting Indicator
ASIP Airspace Flight Inspection Pilot
ASL Above Sea Level
ASMD Assumed
ASN Antenna Structure Number
ASND Ascend
ASO Southern Region
ASOS Automated Surface Observing System
ASP Airport System Plan
ASP Airspace
ASPH Asphalt
ASR Airport Surveillance Radar
ASSOC Associate
ASST Assistant
ASW Southwest Region
ATA Actual Time of Arrival
ATA Air Transport Association of America
ATAM At and Maintain
ATAR Above Transmitted as Received Air Traffic Control
ATC Air Traffic Control
ATCA Air Traffic Control Association
ATCA ATC Advises
ATCAA ATC Assigned Airspace
ATCBI ATC Beacon Interrogator
ATCC ATC Clears
ATCF ATC Facility
ATCH Attach
ATCOR ATC Operations Representative
ATCR ATC Requests
ATCRBS ATC Radar Beacon System
ATCS ATC Specialist
ATCSCC David J. Hurley Systems Command Center
ATCT Airport Traffic Control Tower
ATD Actual Time of Departure
ATFC Account Traffic
ATFM Air Traffic Flow Management
ATIS Automatic Terminal Information Service
ATLC Atlantic
ATM Air Traffic Management
ATM Authentication Maneuver
ATMT Attempt
ATMTC Attempt to Contact
ATN Aeronautical Telecommunications Network
ATND Attend
ATO Aeronautical Telecommunications Operator
ATO Air Traffic Organization
ATOG Allowable Takeoff Gross Weight
ATP Actual Time of Penetration
ATP Air Traffic Procedures
ATPAC Air Traffic Procedures Advisory Committee
ATR Air Transport Rating
ATREP Air Traffic Representative
ATRLS Actual Time of Release
ATSCCP Air Traffic Service Contingency Command Post
ATT American Telephone and Telegraph Company
ATTM At This Time
ATTN Attention
AT-VASIS Abbreviated T Visual Approach Slope Indicator System
ATZ Aerodrome Traffic Zone
AUGRA Authority Granted
AURBO Aurora Borealis
AUREQ Authority is Requested
AUTH Authority
AUTH Authorized
AUTO Automatic
AUTOB Automatic Weather Reporting System
AUW All Up Weight (gross weight)
AUX Auxiliary
AUZ Authorize
AVANA Altitude reservation void for aircraft not airborne by
AVBL Available
AVFP Activate VFR Flight Plan
AVFPNO Pilot failed to activate VFR/DVFR flight plan
AVG Average
AVGAS Aviation Gasoline
AVN Aviation
AWA Advise When Able
AWANS Aviation Weather and NOTAM System
AWBE Automatic Weather Broadcast Equipment
AWE Advise When Established
AWL All Weather Landing
AWOS Automatic Weather Observing/ Reporting System
AWP Aviation Weather Processors
AWP Western-Pacific Region
AWS Air Weather Service (USAF)
AWT Await or Awaiting
AWX Account Weather
AWY Airway
AXPS Air Express
AZM Azimuth
AZRAN Azimuth and Range Data

B

B Base Leg
B Beginning of precipitation (time in minutes) (weather reports only)
B Bering Standard Time (time groups only)
B Blue
B Center clearance delivered
BA Braking Action
BAC Below All Clouds
BACLIN Baroclinic or Baroclinic Prognosis
BAFVC Bids Accepted for the Following Vacancies
BAL Balance
BASE Cloud Base
BASOPS Base Operations Office
BATROP Barotropic or Barotropic Prognosis
BC Back Course
BC Beginning Climb
BC British Columbia
BC Patchy
BCFG Patchy fog
BCH Beach
BCKG Backing
BCM Back Course Marker
BCM Become
BCN Beacon
BCREQ Broadcast Requested
BCST Broadcast
BCSTN Broadcast Station
BDA Bermuda
BDAT Beacon Data (digitized)
BDR Border
BDRY Boundary
BDSLD Bids Solicited
BECMG Becoming
BFDK Before Dark
BFR Before
BGN Began or Begin
BGND Begin or Beginning Descent
BHND Behind
BIFR Before Encountering IFR Conditions
BINOVC Breaks in Overcast
BKN Broken
BL Blowing
BLD Build
BLDG Building
BLDU Blowing Dust
BLDUP Buildup
BLKHLS Black Hills
BLKT Blanket
BLN Balloon
BLO Below
BLO Below Clouds
BLSA Blowing Sand
BLSN Blowing Snow
BLW Below
BLX Block
BLZD Blizzard
BMBR Bomber
BMS Basic Meteorological Services
BND Bound
BNDRY Boundary
BNTH Beneath
BOMB Bombing
BOVC Base of Overcast
BPOC Before Proceeding On Course
BPS Bytes Per Second
BPT Beginning Procedure Turn
BR Bahama Route
BR Branch
BR Mist
BRAF Braking Action Fair
BRAG Braking Action Good
BRAN Braking Action Nil
BRAP Braking Action Poor
BRF Brief
BRG Bearing
BRGT Bright
BRITE Bright Radar Indicator Tower Equipment
BRK Break
BRKG Braking
BRKHIC Breaks in Higher Overcast
BRKSHR Berkshire
BRM Barometer
BS Commercial Broadcasting Station
BSAF Bids Solicited as Follows
BSC Bird Sweep Completed
BSHP Beginning Standard Holding Procedure
BSIAP Beginning Straight In Approach
BSRAP Beginning Standard Range Approach
BSRO Begin Standard Refuel Orbit
BT Back Taxiing
BTL Between Layers
BTN Between
BTR Better
BTWN Between
BUEC Backup Emergency Communication
BUIC Backup Interceptor Control
BUL Bulletin
BUR Bureau
BUS Business
BY Blowing Spray (weather reports only)
BYD Beyond
BZR Buzzer (radar)

C

C Celsius
C Central Standard Time (time groups only)
C Centre (runway ID)
C Circling (approach and landing charts)
C Continental (air mass)
C/A Coarse/Acquisition
CA Clear Above (PIREP only)
CAAS Class A Airspace
CAC Change to Approach Control
CAC Changing to Approach Control
CAC Contact Approach Control
CACT Civil Air Carrier Turbojet
CADO Chief Airport District Office
CAM Canadian Armed Forces Transport Command
CAN Canada
CANFORCE Canadian Armed Force
CANO Catalogue Number
CANOT Canadian NOTAM
CANR Canadian NORAD Region
CAO Change of Appointing Office
CAP Civil Air Patrol
CAP/IS Combined Approach Control/International Station
CAPD Climb at Pilot’s Discretion
CAPT Captain
CARA Check Area Airports
CARF Central Altitude Reservation Function
CARIB Caribbean
CARU Canadian Airspace Reservation Unit
CAS Calibrated Airspeed
CAS Collision Avoidance System
CASCDS Cascades
CAT Category
CAT Clear Air Turbulence
CATX Climb and Cross
CAUFN Caution Advised Until Further Notice
CAVOK Cloud and Visibility OK
CAVU Clear or scattered clouds and visibility greater than ten miles
CAWS Common Aviation Weather Subsystem
CB Cumulonimbus
CBAS Class B Airspace
CBMAM Cumulonimbus Mamma
CBSA Class B Surface Area
CC Carbon Copy
CC Cirrocumulus
CCA Continental Control Area
CCAS Class C airspace
CCC Central Computer Complex
CCC Regional Communications Control Center
CCD City (or County) Civil Defense Director____
CCFP Collaborative Convective Forecast Product
CCLDS Clear of Clouds
CCLKOB Counterclockwise Orbit
CCLKWS Counterclockwise
CCRU Complete Crew
CCRZ Climb and Cruise
CCSA Class C Surface Area
CCSL Standing Lenticular Cirrocumulus
CCTLR Chief Controller
CCUS Cleared Customs
CD Candela
CD Civil Defense
CD Clearance Delivery
CDAS Class D Airspace
CDC Computer Display Channel
CDFNT Cold Front
CDM Collaborative Decision Making
CDN Coordination
CDO Communications Duty Officer
CDSA Class D Surface Area
CE Communications Equipment
CEAS Class E Airspace
CELNAV Celestial Navigation
CENGR Civil Engineer
CENPAC Central North Pacific
CER Climb En Route
CERAP Combined Center/RAPCON
CERT Certificate
CERTIF Certification
CESA Class E Surface Area
CF Change Frequency
CFA Controlled Firing Area
CFAD Composite Flight Data Processing
CFADC Canadian Forces Air Defense Command
CFAP Cleared for Approach
CFM Confirm
CFN Confine
CFP Cold Front Passage
CFPL Carryover From Previous Log
CFR Code of Federal Regulations
CFWSU Central Flow Weather Service Unit
CFY Clarify
CG Coast Guard
CGAS Class G Airspace
CGAS Coast Guard Air Station
CGL Circling Guidance Light
CGLS Coast Guard LORAN Station
CGSTN Congestion
CH Channel
CH Channel continuity check of transmission to permit comparison of record of channel sequence numbers of messages received on the channel
CHAP Chapter
CHARC Characteristic
CHC Chance
CHG Change
CHGO Changing Over
CHM Chemicals
CHNL Channel
CHOK Check Okay
CHOV Changeover
CHRG Charge
CHSPK Chesapeake
CHTR Charter
CI Cirrus
CIC Controller in Charge
CIDIN Common Data Interchange Network
CIFP Cancel IFR Flight Plan
CIFR Cancel IFR Clearance Previously Given
CIFRR Common IFR Room
CIG Ceiling
CINCNORAD Commander in Chief North American Aerospace Defense Command
CIRNAV Circumnavigate
CIRNOT Circuit Notice
CIRVIS Communications Instructions for Reporting Vital Intelligence Sightings
CIT Near or over large towns
CIV Civil
CK Check
CKT Circuit
CL Centre Line
CL Closing Station
CL Course Line
CLA Clear type of ice formation
CLB Climb
CLBI Climb Immediately
CLBN Crash Locator Beacon
CLBR Calibration
CLD Cloud
CLG Calling
CLKOB Clockwise Orbit
CLKWS Clockwise
CLN Colon
CLNC Clearance
CLODA Closing Date
CLOTO Close This Office
CLR Clear
CLRAP Cleared as Planned
CLRS Clear and Smooth
CLSD Closed
CLST Celestial
CLU Circuit Line Up
CM Centimeter
CMA Comma
CMB Climb to or climbing to
CMNC Commence
CMPCT Compact
CMPL Complete or completed or completion
CMPLT Complete
CMPLX Complex
CMPSN Composition
CMPT Component
CMS Construction Maintenance Supervisor
CMSN Commission
CNCL Cancel
CNCNT Concurrently
CNCT Connect
CNDN Canadian
CNL Cancel
CNLFP Cancel Flight Plan
CNS Communications Navigation and Surveillance
CNS Consolidated NOTAM System
CNSTNT Consistent
CNTR Center
CNTRL Central
CNTRLN Centerline
CNVG Converge
CNVRT Convert
CNVSN Conversion
CNVTV Convective
CO Company
CO County
COB Close of Business
COC Climb on Course
COLL Collect
COM Communication
COMB Combine
COML Commercial
COMLO Compass Locator
COMPR Compare
COMPRT Compartment
CONC Concrete
CONCA Continue Calling Until
COND Condition
CONF Confidential
CONFDC Confidence
CONFIG Configuration
CONFIGN Configuration
CONR Continental NORAD Region
CONS Continuous
CONSO CONSOLAN Facility
CONSOL Consol Beacon
CONSOLAN Low or medium frequency long range navigational aid
CONST Construction
CONT Continue or continued
CONTDVD Continental Divide
CONTH Continue to Hold
CONTR Contract
CONTRAILS Condensation Trails
COORD Coordinate
COORD Coordinates
COP Changeover Point
COPCOM Controllers’ Operations and Procedures Committee
COPT Completed Procedure Turn
COR Correct or corrected or correction
CORAS Corridor Assignment
COREQ Confirming Requisition Follows
COT At the coast
COV Cover
CP Circular Polarization
CPA Crash Phone Activated
CPBL Capable
CPD Coupled
CPDLC Controller Pilot Data Link Communications
CPF Complete Power Failure
CPL Current Flight Plan
CPME Calibration Performance Monitoring Equipment
CPN Air Transport Pulse Radar Navigation Aid
CPS Air Transport Pulse Radar Search
CPTY Capacity
CRAD Composite Radar Data Processing
CRAF Civil Reserve Air Fleet
CRC Circle
CRC Cyclic Redundancy Check
CRCHF Crew Chief
CRLC Circulate
CRS Course
CRT Cathode Ray Tube
CRTFY Certify
CRYPTO Cryptographic
CRZ Cruise
CRZAM Cruise and Maintain
CRZWTR Cruise Well to Right
CS Call Sign
CS Cirrostratus
CS/C Combined Station/ Center
CS/T Combined Station/ Tower
CSATR Climb so as to reach
CSATX Climb so as to cross
CSDR Consider
CSDRBL Considerable
CSLDT Consolidate
CST Coast
CTA Control Area
CTAF Common Traffic Advisory Frequency
CTAM Climb to and maintain
CTAS Controlled airspace
CTAX Climb to and cross
CTC Contact
CTCC Change to Center Control or Changing to Center Control
CTCC Contact Center Control
CTCEN Contact Center
CTGY Category
CTL Control
CTLA Control Area
CTLB Control Boundary
CTLR Controller
CTLZ Control Zone
CTN Caution
CTR Control Zone
CTRAC Common Terminal Radar Approach Control
CTSKLS Catskills
CU Cumulus
CUF Cumuliform
CUFRA Cumulus Fractus
CUSNO Customs has been Notified
CUST Customs
CVFP Cancel VFR Flight Plan
CVINO Clearance Void if Not Off
CVN Convene
CVR Cockpit Voice Recorder
CVR Cover
CVRS Computerized Voice Reservation System
CW Continuous Wave
CWM Change Weight Manifest
CWRC Climb Well to Right of Course
CWSU Center Weather Service Unit
CWTR Climb Well to Right
CWY Clearway
CXA Cancel Approved Arrival
CXD Cancel Approved Departure
CYC Cyclonic
CYCLGN Cyclogenesis
CYL Cylinder
CZM Coastal Zone Management

D

D Danger Area
DA Decision Altitude
DA Departure Approved
DAAR Deviation Approved As Requested
DABRK Daybreak
DAE District Airport Engineer
DAIRE Direct Altitude and Identification Readout Equipment
DALGT Daylight
DAP Do All Possible
DAPD Descend at Pilot’s Discretion
DASI Digital Altimeter Setting Indicator
DATIS Data Link Automatic Terminal Information Service
DATIS Digital Automatic Terminal Information Service
DB Decibel
DB Describe
DBA Doing Business As
DBASI Digital Barometer Altimeter Setting Indicator
DBL Double
DBTF Doubtful
DC Direct Current
DCA Defense Communications Acy
DCAVU Clear or scattered clouds and visibility greater than ten, remainder of report missing (weather reports only)
DCD Double Channel Duplex
DCF Deputy Chief
DCKG Docking
DCLRT Decelerate
DCM Defense Combat Maneuvers
DCMSN Decommission
DCMT Document
DCPC Direct Controller Pilot Communications
DCR Decrease
DCRZ Descend to and Cruise
DCS Defense Communications System
DCS Double Channel Simplex
DCT Direct
DDM Difference in Depth of Modulation
DE From (used to precede the call sign of the calling station)
DECCO Defense Commercial Communications Office
DEF Defense
DEFCON Defense Readiness Conditions
DEG Degree
DELPHO Deliver by Telephone
DEMOL Demolition
DENEB Fog Dispersal Operations
DEP Depart
DEP Departure
DEPT Department
DER Departure End of Runway
DES Descend to or Descending to
DESTN Destination
DETRESFA Distress Phase Code Alerting
DEV Deviation
DEW Distant Early Warning
DEWIZ Distant Early Warning Identification Zone
DFCLT Difficult
DFDR Digital Flight Data Recorder
DFL Daily Flight Log
DFNT Definite
DFRS Differs
DFTI Distance From Touchdown Indicator
DFUS Diffuse
DGCGO Dangerous Cargo
DGNL Diagonal
DGR Danger
DH Decision Height
DI Delay Indefinite
DI Departure approval request for IFR flight
DIAM Diameter
DIF Diffuse
DIR Director
DISABLD Disabled
DISC Discontinue
DISEM Disseminate
DIST Distance
DIST District
DISTR Distribute
DIV Divert
DIV Division
DKTS Dakotas
DLA Delay
DLAC Delay Account Of
DLAT Delay Time
DLC Delay Clearance or Delayed Clearance
DLIC Data Link Initiation Capability
DLT Delete
DLVR Deliver
DLVY Delivery
DLY Daily
DMAAC Defense Mapping Acy Aerospace Center
DMAHC Defense Mapping Acy Hydrographic Center
DME Distance Measuring Equipment
DME/P Precision Distance Measuring Equipment
DMEG DME Co-located with Glide Slope
DMEL DME Co-located with Localizer
DMER DME Tactical air navigation with DME only commissioned
DMEV DME Co-located with VOR
DMG Damage
DMNT Dominant
DMO Directives Management Officer
DMSH Diminish
DMSTN Demonstration
DNA Defense Nuclear Agency
DNG Danger
DNS Dense
DNSLP Downslope
DNSTRM Downstream
DNWND Downwind
DO Deputy Commander for Operations
DO Ditto
DOB Date of Birth
DOC Department of Commerce
DOD Department of Defense
DOE Department of Energy
DOLLY Data Link
DOM Domestic
DOT Department of Transportation
DOT1 Transport One Secretary of Transportation
DOT2 Transport Two Deputy Secretary of Transportation
DP Deep
DP Dew Point
DPCR Departure Procedure
DPNG Deepening
DPT Depth
DPTH Depth
DR Dead Reckoning
DR Direct Route
DR Low Drifting
DRCT Direct
DRCTN Direction
DRDU Low Drifting Dust
DRFT Drift
DRG During
DRIR Direct Readout Infrared
DRMS Distance Root Mean Square
DRR Deployment Readiness Review
DRSA Low Drifting Sand
DRSN Low Drifting Snow
DRZL Drizzle
DS Domestic Services (island operations)
DS Dust Storm
DSATR Descend So as to Reach
DSATX Descend So as to Cross
DSB Double Sideband
DSCNT Descent
DSGND Designated
DSIPT Dissipate
DSN Defense Switching Network
DSND Descend
DSNDI Descend Immediately
DSNT Distant
DSPL Display
DSPLC Displace
DSPN Disposition
DSPRL Dispersal
DSR Desire
DSRGD Disregard
DST Distort
DSTC Distance
DSTND Destined
DTAM Descend to and Maintain
DTAX Descend to and Cross
DTE Data Terminal Equipment
DTF Data Transmission Feature
DTG Date Time Group
DTHR Displaced Runway Threshold
DTL Detail
DTLN International Dateline
DTR Data Transmission Request
DTRM Determine
DTRT Deteriorate
DTS Diplomatic Telecommunications Service
DTW Dual Tandem Wheels
DU Widespread Dust
DUATS Direct User Access Terminal System
DUC Dense Upper Cloud
DUPE Duplicate
DUPE Duplicate Message
DUR Duration
DURC During Climb
DURD During Descent
DURG During
DURN Duration
DV Distinguished Visitors
DVFR Day Visual Flight Rules
DVFR Defense Visual Flight Rules
DVLP Develop
DVOLMET Data Link
DVOR Doppler VHF Omnidirectional Radio Range
DVRG Diverge
DVRSN Diversion
DVV Downward Vertical Velocity
DW Dual Wheels
DWG Drawing
DWNDFTS Downdrafts
DWPNT Dew Point
DWRC Descend Well to Right of Course
DWTR Descend Well to Right
DX Duplex
DZ Drizzle

E

E East or Eastern longitude
E Eastern Standard Time (time groups only)
E Ending of precipitation (time in minutes) (weather reports only)
E Equatorial (air mass)
E/G Engineerator
E/R Exchange and Repair
EACLN Expect Approach Clearance
EACNL Expect Approach Clearance Not Later Than
EADIZ Entering Air Defense Identification Zone
EARTS En Route Automated Radar Tracking System
EAS Equivalent Airspeed
EAT Expected Approach Time
EB Eastbound
EBND Eastbound
ECA Enter Control Area
ECAS Enter Controlled Airspace
ECD Except Change Departure to Read
ECM Electronic Counter Measures
ECMSN Electronic Counter Measure Mission
ECOM En Route Communications
ECR Except Change Route to Read
ECSP Electronic Specialist
EDA Early Departure Authorized
EDC Expect Departure Clearance At
EDCT Estimated Departure Clearance
EDR Expect Departure Release At
EEE Error (to be used in AFS as a procedure signal)
EEM Electronic Equipment Modification
EENGR Electrical Engineer
EEP End Exercise Point
EET Estimated Elapsed Time
EFA Entire Field Available
EFAS En Route Flight Advisory Service
EFC Expect Further Clearance At
EFCT Effect
EFF Effective
EFR Expect Further Routing
EFTO Encrypt for Transmission Only
EG Emergency Gear
EGECON Electronic Geographic Coordinator Navigation System
EHA Expect Higher Altitude
EHF Extremely High Frequency (30000 to 300000 MHz)
EIT Electronic Installation Technician
ELAT Estimated Latitude
ELBA Emergency Location Beacon Aircraft
ELEC Electric
ELECN Electrician
ELEV Elevate or elevation
ELIP Elliptical
ELMT Electronic Mechanic Technician
ELNGT Elongate
ELONG Estimated Longitude
ELR Extra Long Range
ELSW Elsewhere
ELT Emergency Locator Transmitter
EM Emission
EMBD Embedded (in cloud layer)
EMBDD Embedded
EMDO Engineering and Manufacturing District Office
EMERG Emergency
EMI Electronic Maintenance Inspector
EMSU Environment Meteorological Support Unit
EMT Electronic Maintenance Technician
ENCTR Encounter
END Stopend (related to RVR)
ENDCE Endurance
ENDG Ending
ENE East North East
ENERN East North Eastern (weather reports only)
ENEWD East North Eastward (weather reports only)
ENG Engine
ENGR Engineer
ENHNCD Enhanced
ENHNCMNT Enhancement
ENR Enroute
ENRC Enroute Chart (followed by name/ title)
ENRT En Route
ENTR Entire
EOBT Estimated Off Block Time
EOD Entered On Duty
EOF Expected Operations Forecast
EP En Route Penetration
EPI Expanded Position Indicator
EQCRT Equipment Certified
EQPT Equipment
EQUIP Equipment
ER Here
ERAD En Route Radar (broadband)
ERMG En Route Metering
ERSP En Route Spacing Program
ERY Early
ESCAT Emergency Security Control of Air Traffic
ESE East South East
ESEC En Route Secondary Radar Beacon
ESERN East South Eastern
ESEWD East South Eastward
ESNTL Essential
ESP En Route Sequencing Program
EST Estimate or estimation
ESTAB Establish
ESV Expanded Service Volume
ET Electronic Technician
ETA Estimated Time of Arrival
ETARS En route tracking automatic radar service
ETC Et Cetera
ETD Estimated Time of Departure
ETE Estimated Time En Route
ETFL Each Thousand Foot Level
ETI Estimated Information
ETIM Elapsed Time
ETO Estimated Time Over Significant Point
ETOV Estimated Time Over
ETP Estimated Time of Penetration
ETR Eastern Test Range
EU Electronic Unit
EUO Emergency Use Only
EV Every
EVAC Evacuation
EVAL Evaluate or evaluation
EVE Evening
EVS Electronic Voice Switching System
EVT Expect Vector To
EXAM Examination
EXC Except
EXCH Exchange
EXCLD Exclude
EXCLV Exclusive
EXCP Except
EXCT Execute
EXDLVY Expedite Delivery
EXEC Executive
EXEC1 President on board civil aircraft
EXEC1F President’s family is aboard aircraft
EXEC2 Vice President is aboard civil aircraft
EXEC2F Vice President’s family is aboard aircraft
EXER Exercise
EXP Expect
EXPC Expect
EXPED Expedite
EXPHO Expedite Delivery by Telephone
EXPS Express
EXQF Expanded Quota Flow
EXREP Expedite Mail Reply
EXSEC Extra Section
EXSHI Expedite Shipment
EXTD Extend
EXTN Extension
EXTRAP Extrapolate
EXTRM Extreme
EXTSV Extensive

F

F Cleared to fix
F Fahrenheit
F Flight Inspection
FA Area Forecast
FA CENTER Aviation Area Forecast Center
FA Final Approach
FA Fuel Advisory
FAA Federal Aviation Administration
FAA For an Approach To
FAA1 SafeAir OneFederal Aviation Administration Administrator
FAA2 SafeAir TwoFederal Aviation Administration Deputy Administrator
FAAP Federal Aid to Airports Program
FAC Facility
FACF Facility Chief
FACSFAC Fleet Area Controlled and Surveillance Facility
FAD Fuel Advisory Departure
FAF Final Approach Fix
FAFAB FSS Assumes Flightplan Area and Service B
FAH Fahrenheit
FAL Facilitation of International Air Transport
FAM Familiar or familiarization
FAMAE Following Amendment Authorized Effective
FAP Final Approach Point
FAR Federal Aviation Regulations
FATFL FSS Assumes Control of Tower Frequencies and Lights
FAX Facsimile
FBO Fixed Base Operator
FC Funnel Cloud
FCA Frequency Change Approved
FCC Federal Communications Commission
FCFSS Contract Flight Service Station
FCO Facility Coordination Officer
FCRP Field Condition Report
FCST Forecast
FCTA Flow Control Time of Arrival
FCWOS Contract Weather Observing Station
FDAT Flight Data
FDC Flight Data Center
FDDL Frequency Division Data Link
FDEP Flight Data Entry and Printout
FDI Fault Detection and Isolation
FDIO Flight Data Input/Output
FDIOR Flight Data Input/Output Repeater
FDPS Flight Data Processing System
FE Flight Engineer
FENKN Fuel Supply Unknown
FENTL Fuel Supply Until
FEW Cloud Coverage 1/8th to 1/4th of sky
FEXHA Fuel Supply Exhausted
FFC For Further Clearance
FFLT Familiarization Flight
FFMN Fixed Federal Monitoring Network
FFR Fire Fighting
FG Fog
FGSB FSS Guarding Service B
FI/P Flight Information (permanent)
FI/T Flight Information (temporary)
FIBI Filed But Impracticable to Transmit
FIC Flight Information Center
FICON Field Condition
FIDO Flight Inspection District Office
FIFO Flight Inspection Field Office
FIFOH Flight Inspection Field Office High Altitude
FIFP Filed IFR Flight Plan
FIG Figure
FIG Flight Inspection Group
FIL Filament
FILG Filling
FILS Florescan Instrument Landing System
FINO Weather report will not be filed for transmission
FIR Flight Information Region
FIRAV First Available
FIRB Flight Information Region Boundary
FIRG Firing
FIRIV Arrival report will be filed with
FIS Flight Information Service
FISA Automated flight information service
FL Flash Advisory
FL Flight Level
FLCTN Fluctuation
FLD Field
FLDST Flood Stage
FLG Falling
FLG Flashing
FLIDAP Flight Data Position
FLIP Flight Information Publication
FLORL Fluorescent Runway Lighting (floodlight system)
FLR Flares
FLRY Flurry
FLT Flight
FLTCK Flight Check
FLTO Flight Orders
FLTWO Flight Watch Outlet
FLUC Fluctuating
FLW Follow
FLWIS Flood Warning Issued
FM Fan Marker
FM From
FMAP Fan Marker Approach
FMH Fan Marker Located with Radio Beacon
FMO Frequency Management Officer
FMS Flight Management System
FMT Format
FMU Flow Management Unit
FNA Final Approach
FNCTN Function
FNT Front
FNTGNS Frontoesis
FNTLYS Frontolysis
FOB Fuel On Board
FOD Foreign Object Debris
FONE Telephone
FORNN Forenoon
FP Flight Plan
FPA Flight Plan Area
FPB Flight Progress Board
FPDI Flight Path Deviation Indicator
FPL Filed Flight Plan
FPL Full Performance Level
FPM Feet Per Minute
FPN Fixed Pulse Radar Navigation Aid
FPNO Flight Plan Not Received
FPP From Present Position
FPR Flight Plan Route
FPRC For Possible Reclearance
FPWA Further Particulars When Available
FQT Frequent
FR Fuel Remaining
FRC Full Route Clearance
FRD Fix Radial Distance
FREQ Frequency
FRFAB FSS Returns Flight Plan Area and Service B
FRH Fly Runway Heading
FRM Form
FRMG Forming
FRMN Formation
FRNG Firing
FROPA Frontal Passage
FROSFC Frontal Surface
FRQ Frequent
FRSB FSS Returns Service B
FRST Frost
FRTFL FSS Returns Control of Tower Frequencies and Lights
FRWF Forecast Wind Factor
FRZ Freeze
FRZLVL Freezing Level
FRZN Frozen
FSDO Flight Standards District Office
FSL Full Stop Landing
FSM Flight Schedule Monitor
FSNFO Flight Standards National Field Office
FSP Flight Strip Printer
FSS Flight Service Station
FT Feet
FT Filing Time
FT Foot
FTAR Following Transmitted as Received (message handling)
FTHR Farther or further
FTHRD Feathered
FTS Federal Telecommunications System
FU Smoke
FURN Furnish
FV Forward Visibility (miles)
FVFP Filed VFR Flight Plan
FW/SIFR Fixed Wing Special IFR
FW/SVFR Fixed Wing Special VFR
FWA Flight Watch Area
FWC Fleet Weather Central
FWCS Flight Watch Control Station
FWD Forward
FWDC Forward Collect
FWP Flight Watch Point
FWRNG Fire Warning
FWS Flight Watch Specialist
FWU Flight Watch Unit
FYI For Your Information
FZ Supercooled/freezing
FZDZ Freezing Drizzle
FZFG Freezing Fog
FZRA Freezing Rain
FZRANO Freezing Rain Sensor Not Available

G

G Green
G Gusts reaching (knots) (weather reports only)
G/A Ground to Air
G/A/G Ground to Air and Air to Ground
GA General Aviation
GA Glide Angle
GA Go ahead resume sending (to be used in AFS as a procedure signal)
GADO General Aviation District Office
GALS Gallons
GBA Give Better Address
GBAS Ground Based Augmentation System
GBL Government Bill of Landing
GBR Give Better Reference
GC Ground Control
GCA Ground Control Approach
GCI Ground Control Intercept
GCO Ground Communication Outlet
GDP Ground Delay Program
GDPGM Ground Delay Program
GEO Geographic
GEOREF Geographical Reference
GES Ground Earth Station
GHZ Gigahertz
GIC GPS Integrity Channel
GICG Glaze Icing
GLD Glider
GLDR Glider
GLFALSK Gulf of Alaska
GLFCAL Gulf of California
GLFMEX Gulf of Mexico
GLFSTLAWR Gulf of St Lawrence
GLONASS Global Orbiting Navigation Satellite System
GLS GBAS Landing System
GMC Ground Movement Chart (followed by name/title)
GMT Greenwich Mean Time
GND Ground
GNDCK Ground Check
GNDFG Ground Fog
GNSS Global Navigation Satellite System (in general)
GNTR Generator
GOV Governor
GOVT Government
GP Glide Path
GPI Ground Point of Intercept
GPS Global Positioning System
GQA Get Quick Answer
GR Hail (greater than 3/4”)
GRAD Gradient
GRADU Gradual
GRASS Grass landing area
GRBL Garble
GRBNKS Grand Banks
GRDL Gradual
GRID Grid point values of processed meteorological data
GRTLKS Great Lakes
GRVL Gravel
GS Glide Slope
GS Ground Speed
GS Ground Stop
GS Snow pellets/small hail (less than 1/4”)
GSA General Services Administration
GSDO General Safety District Office
GSI General Safety Inspector
GSTS Gusts
GSTY Gusty
GTC Gain Time Control
GTCL Great Circle
GTR Greater
GUND Geoid Undulation
GV Ground Visibility
GVG Giving
GVH Government Vehicle
GWT Gross Weight

H

H24 Continuous 24 hour service
HAA Height Above Airport
HADA Hawaiian Defense Area
HADD Hawaiian Air Defense Division
HADIZ Hawaiian Air Defense Identification Zone
HAL Height Above Landing
HANG Hawaiian Air National Guard
HAPI Holding as Previously Instructed
HARS Hazardous Area Reporting Service
HAT Height Above Touchdown
HAZ Hazard
HAZMAT Hazardous Material
HB Homing Beacon
HBN Hazard Beacon
HCVIS High Clouds Visible
HDATZ High Density Traffic Zones
HDF High Frequency Direction Finding Station
HDFRZ Hard Freeze
HDG Heading
HDOP Horizontal Dilution of Precision
HDSVLY Hudson Valley
HDTA High Density Traffic Airport
HDWND Headwind
HEAD Head of State Status
HEL Helicopter
HELI Heliport
HF High Frequency
HFR Hold for Release
HGT Height
HHE Household Effects
HI High
HIALS High Intensity Approach Light System
HIBAL High Altitude Balloon
HIEAT Highest Temperature Equaled for all Time
HIEFM Highest Temperature Equaled for the Month
HIESE Highest Temperature Equaled so Early
HIESL Highest Temperature Equaled so Late
HIFOR High Level Forecast
HIRIV How will arrival report be filed concerning
HIRL High Intensity Runway Lights
HITMP Highest Temperature
HIWAS Hazardous Inflight Weather Advisory Service
HIXAT Highest Temperature Exceeded for all Time
HIXFM Highest Temperature Exceeded for the Month
HIXSE Highest Temperature Exceeded so Early
HIXSL Highest Temperature Exceeded so Late
HJ Sunrise to sunset
HLDG Holding
HLF Half
HLSTO Hailstones
HLTP Hilltop
HN Sunset to sunrise
HND Hundred
HNGR Hangar
HO Service available to meet operational requirements
HOL Holiday
HOP Handoff Point
HOP Helicopter Operations
HOSP Hospital Aircraft
HOW Handover Word
HP Holding Pattern
HPA Hectopascal
HQ Headquarters
HR Here
HR Hour
HRZN Horizon
HS Service available during scheduled operations
HTN Heterodyne
HTR Heater
HUM Humanitarian Mission
HURCN Hurricane
HUREP Hurricane Report
HV High Voltage
HVDF High and very high frequency direction finding stations
HVY Heavy
HWVR However
HWY Highway
HX High Index
HX No specific working hours
HYD Hydraulic
HYDRO Hydrographic
HYR Higher
HZ Haze
Hz Hertz

I

I/IFR Intermittent Instruments
IAARC International Administrative Aeronautical Radio Conference
IAC Instrument Approach Chart
IAD If Authorized DME May be Used
IAF Initial Approach Fix
IAO In and out of clouds
IAP Instrument Approach Procedure
IAR Intersection of Air Routes
IAS Indicated Air Speed
IATA International Air Transport Association
IATSC International Aeronautical Telecommunications Switching Center
IAW In Accordance With
IBASF Intervals Between Aircraft in Stream Type Formation
IBN Identification Beacon
IBND Inbound
IC Ice Crystals
IC Icing (PIREP only)
ICAO International Civil Aviation Organization
ICD Interface Control Document
ICG Icing
ICGIC Icing in Clouds
ICGICIP Icing in Clouds and Precipitation
ICGIP Icing in Precipitation
ID Identify or identifier
IDAT Interfacility Data
IDENT Identification
IDP Individual Development Plan
IF Intermediate approach fix
IF Intermediate Fix
IFAMP If Approach Missed Proceed
IFF Identification Friend/Foe
IFHOL If Holding
IFIM International Flight Information Manual
IFINS If Instrument Conditions Encountered
IFO International Field Office
IFO Interphone
IFONO Interphone (service F) not operative
IFORO Interphone (service F) resumed operation
IFPFP Individual Flight Plans from this Point
IFR Instrument Flight Rules
IFSS International Flight Service Station
IFUN If Unable
IFVLS If Flight Visibility Becomes Less Than
IFVR If Visibility Remains
IGA International General Aviation
IGIA Interacy Group on International Aviation
IIA If incorrect Advise
IISD If incorrect Service Direct
ILAS Instrument Low Approach
ILS Instrument Landing System
ILSP Instrument Landing System Partial
IM Inner Marker
IMAP Immediately After Passing
IMC Instrument Meteorological Conditions
IMDT Immediate
IMF Interrogation Sign
IMG Immigration
IMI Intensity Unknown
IMP Impracticable
IMPL Impulse
IMPR Improve
IMPT Important
IMT Immediate or immediately
IN Inch
INA Initial Approach
INADQT Inadequate
INATS Interruption of Air Traffic Services
INBD Inbound
INC In Clouds
INC Incorporated
INCERFA Uncertainty phase code (alerting service)
INCL Include
INCLV Inclusive
INCOMP Incomplete
INCOR Incorrect
INCR Increase
INDC Indicate
INDEF Indefinite
INDUS Industrial
INF Inland Navigation Facility
INFO Information
INIT Initial Training
INLD Inland
INOF If not off
INOP Inoperative
INP If Not Possible
INPR In Progress
INREQ Information Request
INS Inertial Navigation System
INSP Inspect
INST Instrument
INSTA Instruments Authorized
INSTA Interstate
INSTBY Instability
INSTL Install
INSTR Instruct
INSTR Instrument
INSUF Insufficient Scheduled Time Available
INSUF Unable to Finish
INT Intersection
INTCNTL Intercontinental
INTCP Intercept
INTD Intend
INTER Intermittent
INTFC Interference
INTL International
INTMD Intermediate
INTMT Intermittent
INTNS Intentions
INTR Interior
INTRG Interrogator
INTRMTRGN InterMountain Region
INTRP Interrupt
INTS Intense
INTSF Intensify or intensifying
INTSFY Intensify
INTST Intensity
INTVL Interval
INTXN Intersection
INVES Investigate
INVOF In the Vicinity Of
INVRN Inversion
INVSTAR Investigate and report
IOVC In Overcast
IP Initial Point
IP Instructor Pilot
IP/HHCL Initial Point/Hour Control Line
IPV Improve
IR Ice on Runway
IR IFR Military training route
IRAC Interdepartmental Radio Advisory Committee
IRAD Inbound Radial
IREG Irregular
IRN Interface Revision Notices
IS Island
ISA International Standard Atmosphere
ISB Independent Sideband
ISMGR Island Manager
ISMLS Interim Standard Microwave Landing System
ISOL Isolate
ITCK Issue Time Check
ITNRNT Itinerant
ITRY Itinerary
ITU International Telecommunications Union
IVFRC In VFR Conditions

J

JAL Jet Approach Landing Charts
JATO Jet Assisted Takeoff
JAWYS Join Airways
JBAR Jet Runway Barrier
JCTN Junction
JOUR Journeyman
JP Jet Penetration
JPAP Jet Penetration Approach
JTST Jet Stream
JTSTR Jet Stream

K

K Cold (air mass)
KC Kilocycles
KEPOA Keep this Office Advised
KFRST Killing Frost
KG Kilogram
KHZ Kilohertz
KIAS Knots Indicated Airspeed
KM Kilometers
KMH Kilometers Per Hour
KPA Kilopascal
KT Knots
KW Kilowatt

L

L Left
L Locator
L Logistics
L/MF Low/Medium Frequency
LA Low Approach
LAA Local Airport Advisory
LAADR Low Altitude Arrival/Departure Routing
LAAS Local Area Augmentation System
LAB Laboratory
LABRDR Labrador
LABS Leased Service A/B System
LABS Low Altitude Bombing System
LADP Local Airport Deicing Plan
LAM Logical Acknowledgment
LAN Inland
LARCT Last Radio Contact
LAT Latitude
LAWRS Limited Aviation Weather Reporting Station
LB Left Base
LB Pounds
LC Local Control
LCA Locally
LCL Local or locally
LCT Locate
LCTMP Little Change in Temperature
LD Long Distance
LDA Landing Distance Available
LDA Localizer Type Directional Aid
LDG Landing
LDI Landing Direction Indicator
LDIN Lead in Lighting System
LEN Length
LETFO Letter Follows
LF Low Frequency
LFC Laminar Flow Control
LFNT Low Frequency Intersection
LFR Low Frequency Radio Range
LFT Lift
LGRNG Long Range
LGT Light
LGTD Lighted
LGWV Long Wave
LICOF Land Lines Communications Facilities
LIFR Low IFR
LIH Light Intensity High
LIL Light Intensity Low
LIM Light Intensity Medium
LIN Linearity
LIRL Low Intensity Runway Edge Lights
LK Lake
LKLY Likely
LKTYP Like Type
LL Landline
LLWAS Low Level Wind Shear Alert System
LLWS Low Level Wind Shear
LLZ Localizer
LM Locator Middle
LMM Compass locator at ILS middle marker
LMT Limit
LMT Local Mean Time
LN Line
LNAV Lateral Navigation
LND Land
LNDG Landing
LO Liaison Officer
LO Outer Locator
LOA Letter of Agreement
LOC Localizer
LOCOR Local Coordinator
LODISNAV Long Distance Navigation
LOEAT Lowest Temperature Equaled for all Time
LOEFM Lowest Temperature Equaled for the Month
LOESE Lowest Temperature Equaled so Early
LOESL Lowest Temperature Equaled so Late
LOM Compass locator at ILS outer marker
LONG Longitude
LONGL Longitudinal
LOP Line of Position
LORAC Long Range Accuracy
LORAN Long Range Air Navigation System
LOTMP Lowest Temperature
LOXAT Lowest Temperature Exceeded for all Time
LOXFM Lowest Temperature Exceeded for the Month
LOXSE Lowest Temperature Exceeded so Early
LOXSL Lowest Temperature Exceeded so Late
LP Left Traffic Pattern
LP Linear Polarization
LP Liquid Propane
LP Localizer Performance Without Vertical Guidance
LPV Localizer Performance With Vertical Guidance
LR The last message received by me was
LRA Landing Rights Airport
LRCOM Long Range VHF/UHF Communications
LRG Large
LRG Long Range
LRS Lake Reporting Service
LS Left Side
LS Last message sent by me was or last message was
LSQ Line Squall
LSR Loose Snow on Runway
LST Local Standard Time
LT Turn left after takeoff
LTAV Light and Variable
LTD Limited
LTF Local Training Flight
LTFC Landing Traffic
LTGCA Lightning Cloud to Air
LTGCC Lightning Cloud to Cloud
LTGCCCG Lightning Cloud to Cloud Cloud to Ground
LTGCG Lightning Cloud to Ground
LTGCW Lightning Cloud to Water
LTGIC Lightning in Clouds
LTL Little
LTLCG Little Change
LTNG Lightning
LTR Later
LTR Letter
LTT Landline Teletypewriter
LTTR Latter
LV Leaving
LV Light and Variable
LVE Leave or leaving
LVG Leaving
LVL Level
LVLOF Level Off
LWR Lower
LX Low Index
LYR Layer or layered or layers

M

M In RVR indicates visibility less than lowest reportable sensor value (e.g. M600)
M In temperature field means “minus” or below zero
M Mach number
M Maritime (air mass)
M Metres (preceded by figures)
M Missing (weather reports only)
M Mountain Standard Time (time groups only)
MA Map Analysis
MAA Maximum Authorized (IFR) Altitude
MAC Military Airlift Command
MACH MACH Number (speed ratio to speed of sound)
MACKAY Mackay Radio and Telegraph Company
MACVFR Make Altitude Changes VFR
MAFAP Minimum Altitude over Facility on Final Approach Course
MAG Magnetic
MAGSI Minimum Altitude at Glide Slope Intersection Inbound
MAINT Maintenance
MAL Maintain at Least (altitude)
MALS Medium-Intensity Approach Lighting System
MALSF Medium-Intensity Approach Light System with Sequenced Flashers
MALSR Medium-Intensity Approach Lighting System With Runway Alignment Indicator
MAM Maintenance Assumes Monitor
MAN Manitoba
MAN Manual
MANAM Manual Amendment
MANOP Manual of Operations
MAP Aeronautical Maps and Charts
MAP Missed Approach Point
MAPS Meteorological Aeronautical Presentation System
MAPT Missed Approach Point
MAR At sea
MARPT Municipal Airport
MARSA Military Assumes Responsibility for Separation of Aircraft
MAS Manual A1 Simplex
MAS Military Alert System
MAX Maximum
MB Marker Beacon
MB Millibars
MCA Minimum Crossing Altitude
MCAS Marine Corps Air Station
MCAS(H) Marine Corps Air Station (Helicopter)
MCK Maintenance Check
MCS Master Control Station
MCW Modulated Continuous Wave
MCZNE Minimum When Control Zone Effective
MDA Minimum Descent Altitude
MDF Medium Frequency Direction Finding Station
MDFR Make Descent From
MDFY Modify
MDH Minimum Descent Height
MDT Moderate
MDZ Modernize
MDZN Modernization
MEA Minimum En Route Altitude
MECH Mechanic
MED Medical
MED Medium
MEDEVAC Medical Emergency Evacuation
MEGG Merging
MEHT Minimum Eye Height Over Threshold
MEML Memorial
MET Meteorological aviation routine weather report
METOF Meteorological Officer
METRO Metropolitan
MEX Mexico
MF Medium Frequency
MFL Maintain Flight Level
MFOB Minimum Fuel on Board
MFPOF Master Flight Plan on File
MFS Military Flight Service
MFV Forward visibility more than (miles)
MFXT Meter Fix Time
MGAT Make Good a Track of (degrees)
MGMT Make Good a Magnetic Track of (degrees)
MGMT Management
MGR Manager
MHA Minimum Holding Altitude
MHDF Medium and High Frequency Direction Finding Station
MHDG Magnetic Heading
MHFR Military Height Finder Radar
MHKVLY Mohawk Valley
MHVDF Medium High and Very High Frequency Direction Finding Station
MHz Megahertz
MI Manufacturing Inspector
MI Mile
MI Shallow
MID Middle
MID Midpoint (related to RVR)
MID/ASIA Middle East/Asia Region
MIDIZ MidCanada Identification Zone
MIDN Midnight
MIDPT Midpoint
MIFG Patches of shallow fog not deeper than two meters
MIJI Meaconing Intrusion Jamming Interference
MIL Military
MIMNO Mimeographic Notice
MIN Minute
MINIT Minutes in Trail
MIREQ Minimum Requirements Specified
MIRL Medium Intensity Runway Edge Lights
MIS Missing
MISC Miscellaneous
MISG Missing
MISL Missile
MIT Miles in Trail
MITO Minimum Interval Takeoff
MKCT Make Check Turn
MKD Marked
MKR Marker
MKR Marker Radio Beacon
MLS Microwave Landing System
MLTLVL Melting Level
MM Middle Marker
MM Millimeter
MMACH Maintain Mach
MMO Main Meteorological Office
MNLD Mainland
MNLY Mainly
MNM Minimum
MNPS Minimum Navigation Performance Specification
MNPSA Minimum Navigation Performance Specification Airspace
MNT Monitor
MNTN Maintain
MNVR Maneuver
MOA Memorandum of Agreement
MOA Military Operations Area
MOC Minimum Obstacle Clearance
MOCA Minimum Obstruction Clearance Altitude
MOD Moderate
MOD Modulate or modulation or modulator
MOGR Moderate or Greater
MON Above mountains
MONOK Monitor resumed normal operation
MONOS Monitor out of service
MONTR Monitor
MOPS Minimum Operational Performance Standards
MOPTAR Multiobject Phase Tracking and Ranging
MOREPS Monitor Station Reports
MOT Ministry of Transport (Canada)
MOTNE Meteorological Operational Telecommunications Network Europe
MOV Move
MPH Miles Per Hour
MPP Merit Promotion Program
MPS Meters Per Second
MPVA Maintain a Position VFR and Advise
MRA Minimum Reception Altitude
MRG Medium Range
MRGL Marginal
MRM Maintenance Returns Monitor
MRNG Morning
MRP ATS/MET Reporting Point
MRR Mechanical Reliability Report
MRTM Maritime
MRU Military Radar Unit
MS Minus
MSA Minimum Safe/sector Altitude
MSAW Minimum Safe Altitude Warning
MSG Message
MSGCTR Message Center
MSL Mean Sea Level
MSR Message (transmission identification) has been misrouted
MSSR Monopulse Secondary Surveillance Radar
MSTLY Mostly
MSTR Moisture
MT Mountain
MTCA Minimum Terrain Clearance Altitude
MTI Moving Target Indicator
MTN Mountain
MTR Military Training Route
MTRL Material
MTRY Momentary
MTU Metric Units
MTW Mountain Wave
MU Friction value representing runway surface conditions
MUA Maximum Usable Altitude
MUF Maximum Usable Frequency
MULT Multiple
MUNI Municipal
MV Millivolt
MVA Minimum Vector Altitude
MVDF Medium and very high frequency direction finding station
MVFR Maintain VFR
MVFR Marginal VFR
MVSP Maintain Visual Separation
MWO Meteorological Watch Office
MWRC Maintain Well to Right of Course
MWTCS Modernized Weather Teletypewriter Communications System
MXD Mixed

N

N North or northern latitude
N/A Not Applicable
NA National Air Traffic Controllers Association
NA Not Authorized
NAAS Naval Auxiliary Air Station
NAATS National Association of Air Traffic Control Specialists
NAB Not Above
NACOS National Communications Schedule
NADIN National Airspace Data Interchange Network
NAF Naval Air Facility
NAFEC National Aviation Facilities Experimental Center
NANAC National Aircraft Noise Abatement Council
NAP Not at Present
NAPRS National Airspace Performance Reporting System
NAR North American Route
NAR Not According to Routine
NAS National Airspace System
NAS Naval Air Station
NAS Navigation and Collision Avoidance System
NASA National Aeronautics and Space Administration
NASC National AIS System Centre
NASEO National Airways System Engineering Office
NASP National Airport System Plan
NAT North Atlantic
NAT Not ARTS tracked
NATL National
NATR No Additional Traffic Reported
NATS Noise Abatement Test System
NAV Navigation
NAVAID Navigational Aid
NAVLO Navy Liaison Officer
NAVREP Navy Representative
NB New Brunswick
NB Northbound
NBCAP National Beacon Code Allocation Plan
NBFR Not Before
NBND Northbound
NBRHD Neighborhood
NC National Air Transport Coordinating Committee
NC No Change
NCDC National Climatic Data Center
NCE No Change in Estimates
NCS National Communications System
NCWX No Change in Weather
NDB Nondirectional Radio Beacon
NDB/DME NDB and DME (collocated)
NDBLO Not to Descend Below
NE Northeast
NEB Northeastbound
NEC Necessary
NEF No Further Clearance Required
NEG Negative
NELY Northeasterly
NERN Northeastern
NESS National Environmental Satellite Service
NETR No Essential Traffic Reported
NEW ENG New England
NFDC National Flight Data Center
NFDD National Flight Data Digest
NFLD Newfoundland
NFQ Night Frequency
NFT No Filing Time
NFU Not For Us
NG National Guard
NGT Night
NHD Not Heard
NICS National Airspace System Interfacility Communications System
NIL None
NIL Unable to transmit
NIS Not in System
NL No Layers
NLT Not Later Than
NM Nautical Mile
NMBR Number
NMC National Meteorological Center
NML Normal
NMN No Middle Name
NMR Nautical Mile Radius
NMRS Numerous
NNE North North East
NNERN North North Eastern
NNEWD North North Eastward
NNW North North west
NNWRN North North Western
NNWWD North Westward
NO Not available
NOAA National Oceanic and Atmospheric Administration
NOAC No Action Necessary
NOF NOTAM Office
NOFIN No Further Information
NOHOL Not Holding
NOIFN No Information
NOM National Communications Center
NOMAD Naval Oceanographic Meteorological Automatic Device
NONEG Negative replies not required
NONRVSM Non-RVSM Capable Flight
NOPAC North Pacific
NOPAR Do not pass to Air Defense radar
NOPT No Procedure Turn Required
NORAC No Radio Contact
NORAD North American Aerospace Defense Command
NORDO No Radio
NOREC No Record
NOREP No Report
NORIV No Arrival Report
NORPI No pilot balloon observation will be filed next collection unless weather changes significantly
NORR No Reply Received
NORST No Restrictions
NOS National Ocean Service
NOSI now Simultaneous
NOSIG No Significant Change
NOSPL No Special Observations Taken (weather reports only)
NOSUM NOTAM Summary
NOTAM Notice to Air Missions
NOTAM Notice to Airmen (No longer used)
NOZ Normal operating zone
NPI Nonprecision Instrument
NPRL No Parallel Traffic
NPRM Notice of Proposed Rulemaking
NPRS Nonpersistent
NR Near
NR Number
NRAB Naval Reserve Air Base
NRD No Record of Destination
NRH No Reply Heard
NRP North American Route Program
NRV Nonrevenue
NRW Narrow
NS Nimbostratus
NS Nova Scotia
NSC No Significant Clouds
NSC Nonstandard C/A Code
NSCSWD No Small Craft or Storm Warning are Being Displayed
NSP Nonstandard Holding Pattern
NSSFC National Severe Storm Forecast Center
NSTP Nonstop
NSW No Significant Weather
NTAP National Track Analysis Program
NTAP Notices To Airmen Publication
NTE Not to Exceed
NTFND No Trouble Found
NTFY Notify
NTL National
NTO Name to
NTRP No Traffic Reported
NTSB National Transportation Safety Board
NTZ No Transgression Zone
NUDET Nuclear Detonation
NVA Negative Vorticity Advection
NW Northwest
NWB Northwestbound
NWLY Northwesterly
NWRN Northwestern
NWS National Weather Service
NWSO Naval Weather Service Office
NXT Next

O

O/F On File
O/R On Request
O/T Overtime
OA Overhead Approach
OAC Oceanic Area Control
OAG Official Airline Guide
OANDR Operation and Regulation
OAOI On and Off Instruments
OARTS Oceanic Air Route Tracking System
OAS Obstacle Assessment Surface
OAT Outside Air Temperature
OB On Board
OBL Obliterate
OBND Outbound
OBS Observation
OBSC Obscure obscured or obscuring
OBST Obstacle
OBST Obstruct
OBSTN Obstruction
OC Obstruction Chart
OC On Course
OCA Obstacle Clearance Altitude
OCA Oceanic Control Area
OCAC Oceanic
OCAS Out of Controlled Airspace
OCFNT Occluded Front
OCH Obstacle Clearance Height
OCL Obstacle Clearance Limit
OCLD Occlude
OCLN Occlusion
OCNL Occasional
OCR Occur
OCS Obstacle clearance surface
OCTLA Out of Control Area
ODALS Omnidirectional Approach Lighting System
ODAPS Oceanic Display and Planning System
OFAS Overseas Flight Assistance Service
OFC Office
OFFL Official
OFM Out For Maintenance
OFP Occluded Frontal Passage
OFP Original Flight Plan
OFSHR Offshore
OFW Off Watch
OFXT Outer Fix Time
OFZ Obstacle free zone
OG On Ground
OGN Originate
OHD Overhead
OI On Instruments
OINT Omni Intersection
OIS Operational Information System
OJT On The Job Training
OK Operating Normally
OK We agree or it is correct
OLDI On Line Data Interchange
OLS Optical Landing System
OM Outer Marker
OMSG Our Message
OMTNS Over Mountains
ONER Oceanic Navigational Error Report
ONSHR On Shore
ONT Ontario
ONW On Watch
OOT Out of Tolerance
OPA Opaque white type of ice formation
OPC Operational Control
OPDT Opposite Direction Traffic
OPER Operate
OPMET Operational Meteorological (information)
OPN Open
OPN Operation
OPNML Operations Normal
OPR Operate Operator Operational
OPS Operations
OPSNET Operations Network
ORD Order
ORGPHC Orographic
ORIG Original
ORL Overrun Lights
ORS Over Range Station
OSV Ocean Station Vessel
OT Oral Notice
OT On Time
OTAS On Top and Smooth
OTFC Overflight Traffic
OTLK Outlook
OTP On Top
OTR Other
OTRW Otherwise
OTS Organized Track System
OTS Out of Service
OUBD Outbound
OV Location (PIREP only)
OVC Overcast
OVD Overdue
OVHD Overhead
OVLA Overlay
OVNGT Overnight
OVR Over
OVRN Overrun
OVSEA Overseas
OVTK Overtake
OW One Way
OWF Optimum Working Frequency
OXY Oxygen

P

P In RVR indicates visibility greater than highest reportable sensor value
P Pacific Standard Time
P Polar (air mass)
P Precision approach terrain chart
P Prohibited Area
P/CG Pilot Controller Glossary
P6SM Visibility greater than 6 SM (TAF only)
PA Precision Approach
PA Pressure Altitude
PAC Pacific
PACF Parent FSS assumes control of part time FSS
PADRA Pass to Air Defense Radar
PAEW Personnel and Equipment Working
PAJA Parachute Jumping Activities
PALS Precision Approach Lighting System
PALT Present Altitude
PANS Procedures for Air Navigation Services
PAP ProAirPilot
PAPI Precision Approach Path Indicator
PAR Precision Approach Radar
PARA Paragraph
PAREN Parenthesis
PARL Parallel
PARROT Position Adjustable Range Reference Orientation Transponder
PAT Pattern
PATWAS Pilots Automatic Telephone Weather Answering Service
PAU Present Address Unknown
PAX Passenger
PBCT Proposed Boundary Crossing Time
PBL Probable
PBS Public Buildings Service
PCA Positive Control Area
PCD Proceed
PCK Pilot Check
PCL Pilot Controlled Lighting
PCN Pavement Classification Number
PCPN Precipitation
PCS Permanent Change of Station
PD Period
PDAR Preferential Arrival/Departure Route
PDC Predeparture Clearance
PDDC Proceed Directly on Course
PDMT Predominant
PDMT Predominate
PDOP Position Dilution of Precision
PDR Preferential Departure Route (Stage A)
PDW Priority Delayed Weather
PEN Peninsula
PENT Penetrate or penetration
PER Performance
PERCOM Peripheral Communications
PERF Perforator
PERM Permanent
PFSV Pilot to Forecaster Service
PGTSND Puget Sound
PHYS Physical
PIB Preflight Information Bulletin
PIBAL Pilot Balloon Observation
PIC Pilot in Command
PIR Precision Instrument Runway
PIREP Pilot Weather Report
PIRFC Pilot Requests Forecast
PISE No pilot balloon observation due to unfavorable sea conditions
PISO No pilot balloon observation due to snow
PIT Pilot Instructor Training
PIWI No pilot balloon observation due to high, or gusty, surface wind
PJE Parachute Jumping Exercise
PK WND Peak Wind
PL Ice Pellets
PLA Practice Low Approach
PLASI Pulsating Visual Approach Slope Indicators
PLAT Present Latitude
PLF Private Line Telephone
PLN Flight Plan
PLOB Place of Birth
PLONG Present Longitude
PLS Please
PLT Private Line Teletypewriter
PLVL Present Level
PLW Plow (snow)
PM Post Meridiem
PMSN Permission
PMT Permit
PN Prior Notice Required
PNHDL Panhandle
PNR Point of No Return
PO Dust Devils
PO Post Office
PO Purchase Order
POA Privately Owned Aircraft
POB Persons On Board
POC Proceed or Proceeding On Course
POS Positive
POSS Possible
POV Privately Owned Vehicle
PP Pay Period (number)
PPI Plan Position Indicator
PPINA Radar weather report not available (or omitted for a reason different than those otherwise stated)
PPINE Radar weather report no echoes observed
PPINO Radar weather report equipment inoperative due to breakdown
PPIOK Radar weather report equipment operation resumed
PPIOM Radar weather report equipment inoperative due to maintenance
PPR Prior Permission Required
PPS Propose
PPSN Present Position
PR Partial
PR Photo Reconnaissance
PRBL Probable
PRBLTY Probability
PRBO Position Relief Briefing Observed
PRCF Parent FSS returns control of part time FSS
PRCHT Parachute
PRCTN Precaution
PRECD Precede
PREF Preferred
PRES Pressure
PRESFR Pressure Falling Rapidly
PRESRR Pressure Rising Rapidly
PREV Previous
PRFG Fog Partial
PRI Primary
PRIM Primary
PRIN Principal
PRIND Present Indications Are
PRIRA Primary Radar
PRJMP Pressure Jump (weather reports only)
PRKG Parking
PRN Pseudo Random Noise
PROB Probability
PROB30 Probability 30 Percent
PROB40 Probability 40 Percent
PROC Procedure
PROCD Proceed
PROG Prognosis or prognostic
PROG Progress
PROP Propeller
PROPA Propagation
PROSIG Procedure Signal
PROV Provisional
PRP Prepare
PRSNT Present
PRST Persist
PRVD Provide
PS Passenger Service
PS Plus
PSBL Possible
PSBT Pilot Self Briefing Terminal
PSG Passage
PSG Passing
PSGR Passenger
PSN Position
PSNAL Personal
PSNL Personnel
PSNRP Position Report
PSP Pierced Steel Planking
PSR Packed Snow on Runway
PSR Primary Surveillance radar
PSRI Position Subject to Return of Incumbent
PSRS Position Subject to Rotating Shifts
PST Pacific Standard Time
PT Procedure Turn
PTC Plan to Clear
PTC Positive Target Control
PTCHY Pitchy
PTCP Participate
PTLY Partly
PTN Portion
PTN Procedure Turn
PTP Point To Point
PTR Printer
PTS Polar Track Structure
PUB Public
PUBL Publish
PUP Pickup
PVA Positive Vorticity Advection
PVASI Pulsating Visual Approach Slope Indicator
PVL Prevail
PVLT Prevalent
PVT Private
PWB Pilot Weather Briefing
PWI Proximity Warning Indicator
PWINO Precipitation identifier information not available (weather reports only)
PWR Power
PWRNO Power Failure
PWROK Power Restored
PY Spray

Q

QDL Question asking for a series of bearings typically used in ICAO
QDM Magnetic Heading
QDR Magnetic Bearing
QFE Atmospheric pressure at airport elevation
QFLOW Quota Flow Control Procedures
QFU Magnetic orientation of runway
QJH Shall I run my test tape/a test sentence
QLFY Qualify
QLTY Quality
QN Question
QNH Altimeter subscale setting to obtain elevation when on the ground
QNTY Quantity
QSP Question asking for free of charge relay in ICAO
QSTNRY Quasi Stationary
QTA Shall I cancel telegram number?
QTE True bearing
QTR Quarter
QUAD Quadrant
QUE Quebec
QUJ Questions asking for TRUE track in degrees and time in ICAO

R

R Acknowledgment of receipt (message handling)
R Received (acknowledgment of receipt)
R Restricted area (followed by identification)
R Right (runway identification)
R Runway (used in RVR measurement)
R/O Receive Only
R/OC Receive Only Centers
RA Rain
RAA Remote Airport Advisory
RAAF Royal Australian Air Force
RABA No RAWIN observation no balloons available
RABAL Radiosonde balloon wind data
RABAR Radiosonde balloon release
RAC Request Altitude Change
RAC Rules of the Air and Air Traffic Services
RACE Request Altitude Changes En Route
RACFI Radio and Communication Facilities Inoperative
RACO No RAWIN Observation Communications Out
RACON Radar Responder Beacon
RADAT Radiosonde Observation Data
RADEP Radar Departure
RADNO Report missing account radio failure
RADON Radar Beacon
RADU Weather Radar Analysis and Development Unit
RAF Royal Air Force
RAFC Regional Area Forecast Center
RAFI Radiosonde Observation Not Filed
RAFRZ Radiosonde Observation Freezing Levels
RAG Ragged
RAG Runway Arresting Gear
RAGF Remote Air Ground Facility
RAHE No RAWIN observation no gas available
RAI Runway Alignment Indicator
RAICG Radiosonde Observation Icing At
RAIL Runway Alignment Indicator Lights
RAIM Receiver Autonomous Integrity Monitoring
RAJAM Radar Jamming
RALT Regardless of Altitude
RAM Returned Account Mechanical
RAOB Radiosonde Observation
RAPCON Radar Approach Control
RAPI Radiosonde report already sent in
RARAD Radar Advisory
RAREP Radar Weather Report
RASC Regional AIS System Centre
RASH Rain Showers
RASN Rain and snow or showers of rain and snow
RAVU Radiosonde Analysis and Verification Unit
RAWE No RAWIN observations unfavorable weather
RAWI No RAWIN observations high and gusty winds
RAWIN Upper winds observation (by radio methods)
RAWX Returned Account Weather
RB Rescue Boat
RB Right Base
RBDE Radar Bright Display Equipment
RBN Radio Beacon
RBOC Report Back on Course
RBOF Report Back on Frequency
RBS PP (RBS) Ration by schedule plus compression
RBS Radar Bomb Scoring
RC Reverse Course
RC Road Reconnaissance
RCA Reach Cruising Altitude
RCADV Reverse Course and Advise
RCAG Remote Communications Air Ground Facility
RCALT Reach Cruising Altitude
RCC Rescue Coordination Center
RCD Radar Cloud Detection Report
RCDNA Radar Cloud Detection Report Not Available
RCDNE Radar Cloud Detection Report No Echoes Observed
RCDNO Radar cloud detector inoperative due to breakdown until
RCDOM Radar cloud detector inoperative due to maintenance until
RCF Radio Communication Failure
RCF Remain on Company Frequency
RCH Reach
RCK Radio Check
RCKY Rockies (mountains)
RCL Runway Center Line
RCLL Runway Center Line Lights
RCLM Runway Centerline Marking
RCLR Radio Communications Link Repeater
RCLS Runway Centerline Light System
RCLT Radio Communications Link Terminal
RCMD Recommend
RCN Royal Canadian Navy
RCO Remote Communication Outlet
RCOM En Route Communications
RCON Reconfiguration
RCPT Receipt
RCR Runway Condition Reading
RCRD Record
RCS Rehost Computer System
RCV Receive
RCVNO Receiving Capability Out
RDARA Regional and Domestic Air Route Area
RDAT Radar Data
RDC Reduce
RDG Ridge
RDH Reference Datum Height (ILS)
RDL Radial
RDO Radio
RDS Radius
RDSP Redispatch
RDSPA Redispatch Accepted
RDWND Radar Dome Wind
RE Regard
REC Receive or receiver
RECLR Recleared
RECON Reconnaissance
RECON Reference Conversation
REDL Runway Edge Light
REF Reference
REFONE Reference our telephone conversation
REFORM Reference Form
REG Registration
REG Regulation
REGAL Range and Elevation Guidance for Approach and Landing
REIB Report Established in Block
REIL Runway End Identifier Lights
REINV Reference Invoice
RELBL Reliable
RELCT Relocate
RELET Reference Letter
REMES Reference Message
REMT Relief Electronic Maintenance Technician
RENL Runway End Light
RENOT Regional Office Notice
REOC Report When Established On Course
REP Report or reporting point
REP Represent or representative
REP Research Project
REPAML Reply By Airmail
REPBS Reference PBS message
REPERF Reperforator
REPMES Reply By Message
REPML Reply By Mail
REPTWX Reply By TWX
REQ Request
REQID Request If Desired
REQON Request Consideration
REQRCM Request Your Recommendation
REQSTD Requested
RERTE Reroute
RES Reserve
RES Resident
RESA Runway End Safety Area
RESP Response
RESTR Restrict
REWRC Report When Established Well to Right of Course
RF Radar Facility
RF Radio Frequency
RF Reception Fair
RFA Request Further Airways
RFI Radio Frequency Interference
RFI Ready For Issue
RFL Refuel
RFS Refuse
RFTO Ready For Takeoff
RG Range (lights)
RG Reception good
RGD Ragged
RGLR Regular
RGN Region
RH Relative Humidity
RHC Right Hand Circuit
RHI Range Height Indicator
RHINO Radar Echo Height Information Not Available
RHINO Radar Range Height Indicator Not Operating on Scan
RIF Reclearance In Flight
RIF Reduction In Force
RIMAT Must Ride Company Material
RIOGD Rio Grande
RIS Reports Identification Symbol
RITC Request in Trail Climb
RITD Request in Trail Descent
RITE Right (direction of turn)
RL Report immediately upon leaving
RL Report Leaving
RLA Relay To
RLANO Relay equipment out of operation
RLAOK Relay equipment resumed operation
RLBG Relative Bearing
RLC Report Landing Completed
RLCE Request Level Change En Route
RLETFL Report Leaving Each Thousand Foot Level
RLLS Runway Leading Lighting System
RLNA Request Level Not Available
RLS Release
RLSTN Relay Station
RLTK Rhumbline Track
RLTV Relative
RLV Relieve
RLVL Report Level
RM Remarks
RMK Remark
RMLR Radar Microwave Link Repeater
RMLT Radar Microwave Link Terminal
RMN Remain
RMPCK Ramp Check
RMRK Remark
RN Reception Nil
RNAV Area Navigation
RNFL Rainfall
RNG Army National Guard
RNG Radio Range
RNLS Resume Normal Speed
RNP Required Navigation Performance
RO Regional Office
RO Regulated Output
ROBEPS Radar Operating Below Prescribed Standard
ROBEX Regional OPMET Bulletin Exchange
ROC Rate of Climb
ROCC NORAD Region Operations Control Center
ROD Rate of Descent
RODA Regardless of Destination Airport
ROFOR Route Forecast
ROLET Reference Letter from our office
ROMEMO Reference Our Memorandum
ROMES Reference Message from our office
RON Remaining Overnight
ROPBS Reference PBS message from our office
RORQN Reference requisition from our office
RORU Rest Of Route Unchanged
ROT Rotate
ROTEL Reference telegram from our office
ROTG Rotating
ROTWX Reference our TWX
ROV Report Over
RP Reception Poor (radio logs only)
RP Right Traffic Pattern
RPA Request Present Altitude
RPD Rapid
RPFOD Reported For Duty
RPI Radar Position Indicator
RPL Repetitive Flight Plan
RPLC Replace
RPM Rotation Per Minute
RPOC Report Proceeding On Course
RPR Repair
RPRT Report
RPS Radar Position Symbol
RPSG Report Passing
RPT Repeat
RPT Repeat or I repeat
RQ Indication of a request
RQ Request
RQCL Request Clearance
RQDCZ Request Clearance to Depart VFR and Leave Control Zone at
RQECZ Request Clearance to Enter Control Zone VFR at
RQMNTS Requirements
RQN Requisition
RQOF Request on File
RQP Request Flight Plan
RQP Request Permission
RQPP Request Present Position
RQR Require
RQRP Request Reply
RQS Request Supplementary Flight Plan
RQTAO Request Time and Altitude Over
RR Low or medium frequency radio range stations
RR Radar Range Station
RR Report immediately upon reaching
RR Report Reaching
RRBN Round Robin
RRCVR Remote Receiver
RRL Runway Remaining Lights
RRP Runway Reference Point
RRPD Runway Reference Point Downwind
RRPU Runway Reference Point Upwind
RRS Remainder of Same Route
RRTE Reroute
RS Receiver Station
RS Record Special Observation (weather reports only)
RS Right Side
RSC Rescue Subcenter
RSCD Runway Surface Condition
RSCU Rescue
RSG Rising
RSN Reason
RSOPN Resumed Operation
RSP Responder Beacon
RSR En Route Surveillance Radar
RSTR Restrict
RSU Runway Supervisory Unit
RSVN Reservation
RT Right turn after takeoff
RT Round Trip
RTB Return To Base
RTD Delayed
RTE Route
RTF Radiotelephone
RTG Radiotelegraph
RTHL Runway Threshold Light
RTMTR Remote Transmitter
RTN Return
RTND Retained
RTNE Routine
RTO Report Time Over
RTR Remote Transmitter/Receiver
RTR Returning To Ramp
RTRD Retard
RTRN Return
RTS Return To Service
RTT Radio Teletypewriter
RTX Report time crossing
RTZL Runway Touchdown Zone Light
RUF Rough
RUFORM Reference your form
RULET Reference letter from your office
RUMEMO Reference your memorandum
RUMES Reference message from your office
RURQN Reference requisition from your office
RUT Standard regional route transmitting frequencies
RUTEL Reference telegram from your office
RUTWX Reference your TWX
RV Radar Vector
RV Rescue Vessel
RVO Runway Visibility by Observer
RVR Runway Visual Range
RVRA Runway Visual Range (RVR) ten minute average
RVRANO Runway Visual Range (RVR) ten minute average not available
RVRENO Runway Visual Range (RVR) ten minute extremes not available
RVRM Runway Visual Range (RVR) midpoint
RVRMNO Runway Visual Range (RVR) midpoint not available
RVRNO Runway Visual Range (RVR) not available
RVRR Runway Visual Range (RVR) rollout
RVRRNO Runway Visual Range (RVR) rollout not available
RVRT Runway Visual Range (RVR) touchdown
RVRTNO Runway Visual Range (RVR) touchdown not available
RVS Revise
RVV Runway Visibility Value
RVSM Reduced Vertical Separation Minimums
RVVNO RVV not available
RWRC Remain Well to Right of Course
RWY Runway
RY Runway

S

S South or southern latitude
S/A Semiannual
S/RC Send/Receive Center
SA Duststorm, sandstorm, rising dust or sand
SA Record Observation (weather reports only)
SA Sandstorm or dusting
SA Surveillance Approach
SABH Simultaneous Automatic Broadcast Homer
SADT Same Direction Traffic
SAFI Semiautomatic Flight Inspection
SAFI Semiautomatic Flight Inspection Aircraft
SALS Short Approach Lighting System
SALS Simple Approach Lighting System
SALSF Short Approach Lighting System with Sequenced Flashing Lights
SAN Sanitary
SAO Surface Aviation Observation
SAP Soon As Possible
SAPD Speed at Pilots Discretion
SAR Search and Rescue
SARPS Standards and Recommended Practices
SASK Saskhewan
SATFY Satisfy or satisfactory
SATR So As To Reach
SAVASI Simplified Abbreviated Visual Approach Slope Indicator
SAWRS Supplementary Aviation Weather Reporting Station
SAYTA Say Time Able
SB Southbound
SBAS Satellite-Based Augmentation System
SBFC Standby For Further Clearance
SBND Southbound
SBSD Subside
SC Stratocumulus
SCAN Self Correcting Automatic Navigation
SCANO Automatic Scanning Unit Out of Service
SCAOK Automatic Scanning Unit Returned to Service
SCAT Security Control of Air Traffic
SCATANA Security Control of Air Traffic and Air Navigation Aids
SCC System Command Center
SCLN Semicolon
SCND Second (in line)
SCS Single Channel Simplex
SCSL Standing Lenticular Stratocumulus
SCT Scattered
SCTR Sector
SCTY Security
SDB Scheduled Data Base
SDBY Standby
SDF Simplified Directional Facility
SE Southeast
SE System Engineer
SEADRM Seadrome
SEB South Eastbound
SEC Second (time)
SECMR Sector Manager
SECRA Secondary Radar
SECT Sector
SEL Space Environment Laboratory
SELCAL Selective Calling
SELS Severe Local Storms
SELY South Easterly (weather reports only)
SENS Sensitivity
SEPN Separation
SEQ Sequence
SER Service
SERN South Eastern
SES Supervisory Electronics Specialist
SESC Space Environment Service Center
SET Stack Entry Time
SEV Severe
SF Standard Form
SFA Single Frequency Approach
SFC Surface
SFERICS Atmospherics
SFL Sequence Flashing Lights
SFO Sector Field Office
SFO Simulated Flame Out
SFPP Stored Flight Plan Program
SFU Sector Field Unit
SG Snow Grains (weather reports only)
SGD Signed
SGD Solar Geophysical Data
SGFNT Significant
SGL Signal
SH Showers
SHF Super High Frequency
SHFT Shift
SHGR Hail Showers
SHGS Hail Showers (small)
SHLW Shallow
SHORN Short Range Navigation System
SHP Standard Holding Procedure
SHPL Ice Pellet Showers
SHRA Rain Showers
SHRT Short
SHRTLY Shortly
SHRTWV Shortwave
SHSN Snow Showers
SHTDN Shutdown
SHUD Should
SHWR Shower
SI Straight In Approach
SIA Standard Instrument Approach
SIAP Standard Instrument Approach Procedure
SID Standard Instrument Departure
SIERNEV Sierra Nevada
SIF Selective Identification Feature
SIG Signature
SIGMET Significant Meteorological Information
SIGWX Significant Weather
SIM Simulated Approach
SIMUL Simultaneous
SIR Snow and Ice on Runway
SIWL Single Isolated Wheel Load
SJP Standard Jet Penetration
SK Sky condition
SKC Sky clear
SKED Schedule
SL Sea Level
SL Sick Leave
SLCT Select
SLD Solid
SLGT Slight
SLMM Simultaneous Compass Locator at Middle Marker
SLO Slow
SLOM Simultaneous Compass Locator at Outer Marker
SLP Sea Level Pressure
SLP Slope
SLP Speed Limiting Point
SLR Slush on Runway
SLRAP Standard Low Frequency Range Approach
SLS Side Lobe Suppression
SLT Sleet
SLW Slow
SM Statute Mile
SMC Squawk Mode Code
SMC Surface Movement Control
SML Small
SMR Statute Mile Radius
SMR Surface Movement Radar
SMRY Summary
SMS Synchronous Meteorological Satellite
SMS Systems Maintenance Sector
SMT Submit
SMTH Smooth
SMTM Sometime
SMWHT Somewhat
SN Snow
SN Strategic Navigation
SN Systems Navigation
SNBNK Snowbank
SND Sand or sanded or sanding
SNFLK Snowflake
SNGL Single
SNOINCR Snow depth increase in past hour
SNOWTAM NOTAM reporting the presence or removal of hazardous conditions due to snow, ice, slush or standing water associated with snow, slush or ice on the movement area
SNSH Snow Showers
SNW Snow
SNWFL Snowfall
SOAP Spectrometric Oil Analysis Program
SOB Souls On Board
SOCC NORAD Sector Operations Control Center
SOM Satellite Communication
SOMSG See Our Message
SOP Standard Operating Procedure
SORAP Standard Omni Range Approach
SP Standard Holding Pattern
SP Station Pressure
SPAN Stored Program for Alpha Numerics
SPB Seaplane Base
SPCLY Especially
SPD Speed
SPEC Specification
SPECI Aviation selected special weather report
SPKL Sprinkle
SPL Special
SPL Supplementary Flight Plan
SPLNS South Plains
SPO Strategic Plan of Operation
SPOT Spot Wind
SPRD Spread
SPRL Spiral
SPS Standard Positioning Service
SPT Strategic Planning Team
SQ Squall
SQDN Squadron
SQK Squawk
SQLN Squall Line
SR Standard Range Approach
SR Sunrise
SRA Surveillance Radar Approach
SRCH Search
SRE Surveillance Radar Element of precision approach radar system
SRG Short Range
SRND Surround
SRPN Special Requisition Priority Number
SRR Search and Rescue Region
SRY Secondary
SS Sandstorm
SS Sunset
SSALF Simplified Short Approach Lighting System with Sequenced Flashers
SSALR Simplified Short Approach Lighting System with Runway Alignment Indicator Lights
SSALS Simplified Short Approach Lighting System
SSB Single Side Band
SSE South South East
SSERN South South Eastern
SSEWD South South Eastward
SSNO Request no SIDs or STARs
SSR Secondary Surveillance Radar
SST Supersonic Transport
SSW South South West
SSWRN South South Western
SSWWD South South Westward
ST Saint
ST Stratus
STA Straight In Approach
STADMR Station Administrator
STAGN Stagnation
STALO Stabilized Local Oscillator
STAR Standard Terminal Arrival
STATE Military, customs, or police services
STBL Stable
STCLB Start Climb
STD Standard
STDST Start Descent
STDY Steady
STF Stratiform
STFRA Stratus Fractus
STFRM Stratiform
STG Strong
STLT Satellite
STM Storm
STMGR Station Manager
STMP Special Traffic Management Program
STN Station
STNR Stationary
STNRY Stationary
STOL Short Takeoff and Landing
STR Subject Terminal Control Release
STRO Stereo Routes
STS Status
STWL Stopway Light
STWY Stopway
SUA Special Use Airspace
SUB Substitute
SUBFIX Subject to Correction
SUBJ Subject to
SUF Sufficient
SUG Suggest
SUP Supply
SUPCHG Supercharge
SUPPL Supplement
SUPPS Regional Supplementary Procedures
SUPR Superior
SUPSD Supersede
SUPT Superintendent
SUPVR Supervisor
SURPIC Surface Picture
SUSP Suspend
SVC Service
SVCBL Serviceable
SVFR Special VFR
SVG Serving
SVN Space Vehicle Number
SVR Severe
SVRL Several
SW South West
SWAP Severe Weather Avoidance Plan
SWB Scheduled Weather Broadcast
SWB South Westbound
SWLG Swelling
SWLY South Westerly
SWRN South Western
SWSL Supplemental Weather Wervice Location
SWY Stopway
SX Stability Index
SXN Section
SYD Release Subject Your Discretion
SYNOP Synoptic
SYNS Synopsis
SYS See Your Service
SYS System

T

T Temperature
T Trace (weather reports only)
T Training
T Tropical (air mass)
T True (bearing)
T/R Transportation Request
TA Temperature (PIREP only)
TA Total Aboard
TA Transition Altitude
TAC Terminal Area Chart
TACAN Tactical Air Navigational Aid
TACLO Tactical Air Command Liaison Officer
TACR Tactical Air Navigation
TAD Tower Approach and Departure Control Facility
TAF Terminal Aerodrome Forecast
TAIL Tail Wind
TAND Tandem
TANDA Time and Attendance Report
TAO TACAN only
TAO Time and Altitude Over
TAPER Temporary Appointment Pending Establishment of a Register
TAR Terminal Area Surveillance Radar
TARND Turn Around
TARS Terminal Automated Radar Services
TARS Tethered Aerostat Radar System
TAS True Air Speed
TASR Terminal Area Surveillance Radar
TAWOG Travel Arrangements Without Government Expense
TB Turbulence (PIREP only)
TBJT Turbojet
TC Time Check
TC Tropical Cyclone
TCA Tactical Customer Advocate
TCA Terminal Control Area
TCAS Traffic Alert and Collision Avoidance System
TCH Threshold Crossing Height
TCHD Threshold Crossing Height Downwind
TCHU Threshold Crossing Height Upwind
TCNTL Transcontinental
TCOM Terminal Communications
TCP Transfer of Control Point
TCU Towering Cumulus
TD Touchdown
TD Transmitter Distributor
TDA Today
TDEL Time Delay
TDLS Terminal Data Link System
TDO Tornado
TDOP Time Dilution of Precision
TDWR Terminal Doppler Weather Radar
TDY Temporary Duty
TDZ Touchdown Zone
TDZE Touchdown Zone Elevation
TDZL Touchdown Zone Light (system)
TEC Tower En Route Control
TECA Tower En Route Control Area
TECR Technical Reason
TEL Telecommunications
TEL Telephone
TELAU Teleautograph
TELCO Telephone Company
TELCON Telephone Conference
TELEX Telephone Exchange
TELRY Telegraph Reply
TEMP Temperature
TEMPO Temporary
TEND Trend
TERPS Terminal Instrument Procedures
TET Tetrahedron
TF Terrain Following
TFC Traffic
TFMS Traffic Flow Management System
TFR Temporary Flight Restriction
TFRCD Traffic Received
TFZ Traffic Zone
TGL Touch and Go Landing
TGS Taxiing Guidance System
THD Thunderhead
THDR Thunder
THK Thick
THLD Threshold
THN Thin
THR Threshold
THRFTR Thereafter
THRU Through
THRUT Throughout
THSD Thousand
THTN Threaten
TIBA Traffic Information Broadcast by Aircraft
TIL Until
TINOP Transponder Inoperative
TIP Until Past
TIPS Terminal Information Processing System
TKOF Takeoff
TLM Telemetry
TLRNC Tolerance
TLTP Too Long To Print
TLWD Tailwind
TM Time (PIREP only)
TM Traffic Management
TMA Terminal Control Area
TMPA Traffic Management Program Alert
TMPRY Temporary
TMT Transmit
TMW Tomorrow
TNA Turn Altitude
TNDCY Tendency
TNGT Tonight
TNH Turn Height
TNTV Tentative
TO Travel Order
TOC To Be Continued
TOC Top of Climb
TOD Time of Delivery
TODA Takeoff Distance Available
TOG Takeoff Gross Weight
TOP Cloud top
TOR Time of Receipt
TOR Traffic on Request
TORA Takeoff Run Available
TOT Time of Transmission
TOVC Top of Overcast
TP Turning Point
TP Type Aircraft (PIREP only)
TPA Traffic Pattern Altitude
TPG Topping
TR Track
TR VFR low altitude training routes
TRA Temporary Reserved Airspace
TRACAB Terminal Radar Approach Control in Tower Cab
TRACON Terminal Radar Approach Control Facility
TRAD Terminal Radar
TRAN Transient
TRANS Transmit or transmitter
TRBL Trouble
TRCV Tricolor Visual Approach Slope Indicator
TRG Training
TRIB Tributary
TRK Track
TRLVL Transition Level
TRML Terminal
TRMT Terminate
TRNG Training
TRNSP Transport
TROF Trough
TROP Tropopause
TRPCD Tropical Continental (air mass)
TRPCL Tropical
TRPLYR Trapping Layer
TRRN Terrain
TRSA Terminal Radar Service Area
TRSN Transition
TRTD Treated
TS Team Supervisor
TS Thunderstorm
TSA Transportation Security Administration
TSATLC TransAtlantic
TSEC Terminal Secondary Radar Beacon
TSFR Transfer
TSGR Thunderstorm with Hail
TSGS Thunderstorm with Small Hail
TSMNO Transmitting Capability out of Service
TSMOK Transmitting Capability Returned to Service
TSNO Thunderstorm Information Not Available
TSNT Transient
TSO Technical Standard Order
TSPAC TransPacific
TSPL Thunderstorm with Ice Pellets
TSRA Thunderstorm with Rain
TSSA Thunderstorm with Duststorm or sandstorm
TSSN Thunderstorm with Snow
TSTM Thunderstorm
TT Teletypewriter
TTS Teletype Switching Facilities
TTY Teletypewriter Station
TURB Turbulence
TURBC Turbulence
TURBT Turbulent
TVASIS T Visual Approach Slope Indicator System
TVL Travel
TVOR Terminal VOR
TWD Toward
TWEB Transcribed Weather Broadcast
TWI Twilight
TWR Aerodrome Control Tower
TWR Tower
TWRG Towering
TWS Radar Track While Scan
TWX Teletypewriter Exchange Service
TWY Taxiway
TWYL Taxiway Link
TXG Taxiing
TXL Taxilane
TXT Text
TYP Type Aircraft
TYPH Typhoon
TYPNO Teletypewriter Communications Out of Service
TYPOK Teletypewriter Communications Returned to Service

U

U Intensity Unknown (weather reports only)
U/S Unserviceable
UA Routine PIREP
UA Unable to approve arrival for the time specified
UAB Until Advised By
UAC Upper Area Control Center
UAG Upper Atmosphere Geophysics
UAR Upper Air Route
UAS Unmanned Aircraft Systems
UAT Until Advised by the Tower
UCDWN Until Cleared Down
UCLT Until Cleared to Land by the Tower
UD Unable to approve departure for the time specified
UDDF Up and Down Drafts
UDF Ultra High Frequency Direction Finding Station
UERE User Equivalent Range Error
UFA Until Further Advised
UFN Until Further Notice
UFO Unidentified Flying Object
UHA Unable Higher Altitude
UHDODT Unable Higher Due Opposite Direction Traffic
UHDSDT Unable Higher Due Same Direction Traffic
UHDT Unable Higher Due Traffic
UHDT Unable Higher Due Traffic
UHF Ultra High Frequency
UIC Upper Information Center
UIR Upper Flight Information Region
ULDT Unable Lower Due Traffic
ULR Ultra Long Range
UM Unable to Maintain
UN Unable
UNA Unable
UNAP Unable to Approve
UNAPV Unable to Approve
UNAR Unable to Approve Altitude Requested
UNATNDD Unattended
UNAVBL Unavailable
UNCC Unable to Contact Company Radio
UNDLD Undelivered
UNEC Unnecessary
UNHRD Unheard
UNID Unidentified
UNKN Unknown
UNL Unlimited
UNLGTD Unlighted
UNMON Unable to Monitor
UNMON Unmonitored
UNOFFL Unofficial
UNRDBL Unreadable
UNREL Unreliable
UNRELBL Unreliable
UNRR Unable to Approve Route Requested
UNRSTD Unrestricted
UNSATFY Unsatisfactory
UNSBL Unseasonable
UNSKED Unscheduled
UNSTBL Unstable
UNSTDY Unsteady
UNSTL Unsettle
UNTC Unable to Establish Contact
UNUSBL Unusable
UP Unknown Precipitation
UPDFTS Up Drafts
UPDT Update
UPR Upper
UPSLP Upslope
UPSTRM Upstream
UQOT Unquote
URAUZ You are authorized
URG Urgent
URIZR Your recommendation is requested
U/S Unserviceable
USA U.S. Army
USAF U.S. Air Force
USAFIB U.S. Army Aviation Flight Information
USBL Usable
USCG U.S. Coast Guard
USMC U.S. Marine Corps
USN U.S. Navy
USNO United States Naval Observatory
USNOF United States NOTAM Office
USNS United States NOTAM System
USP Urgent Special Observation (weather reports only)
UTA Upper control area
UTC Coordinated Universal Time
UTCOK Coordinated Universal Time Coordinate Check Completed
UUA Urgent PIREP
UVV Upward Vertical Velocity
UW Upwind
UWNDS Upper Winds

V

V Variable (weather reports only)
VA Victor Airways
VA Volcanic Ash
VAC Visual Approach Chart
VACAPES Virginia Capes
VADA VFR Arrival Delay Advisory
VAL Valleys
VAN Runway control van
VAPS V/STOL Approach System
VAR Magnetic Variation
VAR Visual Aural Radio Range
VARN Variation
VASI Visual Approach Slope Indicator
VASIS Visual Approach Slope Indicator System
VC Vicinity
VCFG Fog in Vicinity
VCNTY Vicinity
VCOT VFR Conditions On Top
VCTR Vector
VDF Very High Frequency Direction Finding Station
VDOP Vertical Dilution of Precision
VDP Visual Descent Point
VER Vertical
VF Maintaining Visual Flight
VFLT Visual Flight
VFPR Via Flight Planned Route
VFR Visual Flight Rules
VFRSA VFR Restrictions Still Apply
VFY Verify
VHF Very High Frequency
VIA By way of
VIP Very Important Person
VIP Visual Integrated Presentation
VIS Visibility
VLCTY Velocity
VLF Very Low Frequency
VLFD Via Low Frequency Direct
VLNT Violent
VLR Very Long Range
VLY Valley
VM Voice Modulation
VMC Visual Meteorological Conditions
VNAV Vertical Navigation
VOD Via Omni Direct
VOL Volume
VOLMET Meteorological information for aircraft in flight
VOPR Voice Operated Relay
VOR Very High Frequency Omnidirectional Range
VOR APPR VOR Approach
VOR/DME Very High Frequency Omnidirectional Range Collocated with Distance Measuring Equipment
VOR/DME VHF Omnidirectional Range/Distance Measuring Equipment
VOR/DME VOR and DME (collocated)
VOROC VOR On Course
VORTAC Very High Frequency Omnidirectional Range Collocated Tactical Air
VORTAC VOR and TACAN (collocated)
VORTAC VOR collocated with TACAN
VOT VOR airborne equipment test facility
VOT VOR Test Facility
VOT VOR Test signal
VOT Vorticity
VOU Voucher
VR Veer
VR VFR military training routes
VRB Variable
VRBL Variable
VRG Visual Reference Gate
VRISL Vancouver Island, BC
VRT MOTN Vertical Motion
VSA By visual reference to the ground
VSB Visible
VSBY Visibility
VSBYDR Visibility Decreasing Rapidly
VSBYIR Visibility Increasing Rapidly
VSL Vessel
VSP Vertical Speed
VSPI Visual Glide path Indicator
VSTOL Vertical/Short Takeoff and Landing
VTOL Vertical Takeoff and Landing
VV Vertical Visibility (indefinite ceiling)

W

W Warm (air mass)
W West or western longitude
W White
WA AIRMET
WAAS Wide Area Augmentation System
WAC World Aeronautical Chart
WAFC World Area Forecast Center
WAIOP Will Accept If Offered the Position
WB Westbound
WBAR Wing Bar Lights
WBND Westbound
WBRBN Will Be Reported by NOTAM
WBRH Weather Bureau Regional Headquarters
WBTS Whereabouts
WCLC Watch Check List Completed
WDC1 World Data Centers in Western Europe
WDC2 World Data Centers throughout rest of world
WDI Wind Direction Indicator
WDLY Widely
WDSPR Widespread
WDSPRD Widespread
WEA Weather
WEF With Effect From
WFO Weather Forecast Office
WFP Warm Front Passage
WG Working Group
WGS World Geodetic System
WGS84 World Geodetic System 1984
WI Within
WIBIS Will Be Issued
WICA While in Control Area
WICZ While in Control Zone
WID Width
WIE With Immediate Effect
WILCO Will Comply
WINT Winter
WINTEM Forecast upper wind and temperature for aviation
WIP Work In Progress
WK Weak
WKDAY Weekday
WKEND Weekend
WKN Weaken
WL Will
WLAV Will Advise
WMO World Meteorological Organization
WMSC Weather Message Switching Center
WND Wind
WNW West North West
WNWRN West North Western
WNWWD West North Westward
WO Washington Office
WO Without
WP Waypoint
WPLTO Western Plateau
WPM Words Per Minute
WPRT Waypoint Report
WPT Waypoint
WR Wet Runway
WRC Well to Right of Course
WRM Warm
WRMFNT Warm Front
WRNG Warning
WRS Worse
WS SIGMET
WS Weak Signals
WS Wind Shear
WSCMO Weather Service Contract Meteorological Observatory
WSHFT Wind Shift
WSO Weather Service Office
WSOM Weather Service Operations Manual
WSP Weather System Processor (replacement for LLWAS)
WSR Wet Snow on Runway
WSSF National Weather Service Support Facility
WSSU National Weather Service Support Unit
WSTCH Wash Range
WSW West South west
WSWRN West South Western
WSWWD West South Westward
WT Weight
WTR Water
WTR Well To Right
WTSPT Waterspout
WU Western Union Telegraph Company
WV Wave
WV Wind at altitude (PIREP only)
WW Severe weather forecast
WWW World Wide Web
WX Weather
WX Weather at altitude (PIREP only)
WXCON Weather reconnaissance flight pilot report
WYAIO Will You Accept if Offered the Position of

X

X Cross
X Obscured sky condition
XBAR Crossbar
XCP Except
XFSS Auxiliary Flight Service Station
XH Special handling service for aircraft
XNG Crossing
XPC Expect
XPLOS Explosive
XREP Auxiliary Report
XS Atmospherics
XTAL Crystal
XTLK Cross Talk
XW Crosswind
XX Heavy (to qualify weather phenomena, e.g. XXRA heavy rain)

X

X Cross
X Obscured sky condition
XBAR Crossbar
XCP Except
XFSS Auxiliary Flight Service Station
XH Special handling service for aircraft
XNG Crossing
XPC Expect
XPLOS Explosive
XREP Auxiliary Report
XS Atmospherics
XTAL Crystal
XTLK Cross Talk
XW Crosswind
XX Heavy (to qualify weather phenomena, e.g. XXRA heavy rain)

Y

Y Yukon Standard Time (time groups only)
YCZ Yellow Caution Zone (runway lighting)
YD Yards
YDA Yesterday
YES Yes (affirmative)
YKN Yukon
YL Approach light lane
YLSTN Yellowstone
YMSG Your Message
YMSGD Your Message Date
YR Your

Z

Z Greenwich Mean Time
Z Jet terminal area
ZI Zonal Index
ZI Zone of Interior
ZM Z marker (VHF station location marker)
ZRNO Freezing Rain Information Not Available