GEN 2.2  Abbreviations used in AIS publications

Abbreviations not included in ICAO Doc. 8400 are marked with (*)

A - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
ABAS* Aircraft Based Augmentation System
ABC* Advance Booking Charter Flight
ABNAerodrome beacon
ACARS(to be pronounced “AY-CARS”) Aircraft Communication addressing and Reporting System.
ACASAirborne collision avoidance system
ACCArea control centre or area control
A-CDMAirport Collaborative Decision Making
ACFTAircraft
ACKAcknowledge
ACTActive or activated or activity
ADAerodrome
ADCAerodrome chart
ADEP* Airport of Departure
ADES* Airport of Destination
ADEXP* ATS Data Exchange Presentation
ADFAutomatic direction-finding equipment
ADIZ(to be pronounced “AY-DIZ”) Air defence identification zone
ADS-BAutomatic dependent surveillance - broadcast
ADS-CAutomatic dependent surveillance - contract
AESAircraft earth station
AFILFlight plan filed in the air
AFISAerodrome flight information service
AFN* Air Traffic Services Facilities Notification
AFSAeronautical fixed service
AFTNAeronautical fixed telecommunication network
A/GAir-to-ground
AGAAerodromes, air routes and ground aids
AGLAbove ground level
AICAeronautical information circular
AIDCAir traffic services inter-facility data communications
AIMAeronautical Information Management
AIPAeronautical information publication
AIRACAeronautical information regulation and control
AIRMETInformation concerning en-route weather phenomena which may affect the safety of low-level aircraft operations
AISAeronautical information services
ALRSAlerting service
ALSApproach lighting system
ALTAltitude
ALTNAlternate or alternating (light alternates in colour)
ALTNAlternate (aerodrome)
ALTRV* Altitude Reservation
AMAArea minimum altitude
AMC* Airspace Management Cell
AMC* Acceptable Means of Compliance
AMDTAmendment (AIP Amendment)
AMHS* Aeronautical Message Handling System
AMO* Aeronautical Meteorological Office
AMOS* Aerodrome Meteorological Observing System
AMS* Aeronautical Meteorological Station
AMSLAbove mean sea level
ANA* Aeroportos de Portugal, SA
ANAC* Autoridade Nacional da Aviação Civil (Portuguese CAA)
ANCAeronautical Chart 1:500 000
ANM* ATFM Notification Message
ANP* Air Navigation Plan
AOAircraft Operator
AOCAerodrome obstacle chart (followed by type and name/title)
AOC* Air operator certificate
APAPI(to be pronounced “AY_PAPI”) Abbreviated precision approach path indicator
APCHApproach
APDCAircraft parking/docking chart (followed by name title)
APIS* Aircraft Parking and Information System
APPApproach control office or approach control or approach control service
APRApril
APUAuxiliary Power Unit
APVApproach procedure with vertical guidance
ARCArea chart
AROAir traffic services reporting office
ARPAerodrome reference point
ARPAir-report (message type designator)
ARRArrival (message type designator)
ARRArrive or arrival
ART* Article
ASAltostratus
ASDAAccelerate-stop distance available
ASEAltimetry system error
ASHTAMSpecial series of Notam notifying, by means of a specific format, change in activity of a volcano, a volcanic eruption and/or volcanic ash cloud that is of  significance to aircraft operations
ASM* Airspace Management
A-SMGCS* Advanced Surface Movement Guidance and Control
ASMGL* Aircraft Stand Manoeuvring Guidance Lights
ASPHAsphalt
ATCAir traffic control (in general)
ATCSMACAir traffic control surveillance minimum altitude chart
ATFCM* Air Traffic Flow and Capacity Management
ATFMAir traffic flow management
ATFMX* ATFM Exempt Approved
ATISAutomatic terminal information service
ATMAir traffic management
ATM* Automatic Teller Machine
ATNAeronautical telecommunication network
ATPAt... (time or place)
ATSAir traffic services
ATZAerodrome traffic zone
AUGAugust
AUTOAutomatic
AVBLAvailable or availability
A-VDGSAdvanced Visual Docking Guidance System
AVGASAviation gasoline
B - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
BAK* Type of  Arresting Gear
BARO-VNAVBarometric vertical navigation (to be pronounced “BAA-RO - VEE-NAV “)
BDRYBoundary
BFRBefore
BIRDTAM* NOTAM Reporting Bird Hazard
BLWBelow
BP* Breakaway point
BRGBearing
B-RNAV* Basic Area Navigation
BTNBetween
BYD* Beyond
C - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
CDegrees Celsius (Centigrade)
C* Charts
CAComando Aéreo
CAACivil Aviation Authority or Civil Aviation Administration
CAR* Caribbean
CASA* Computer Assisted Slot Allocation
CATCategory
CBH* Cloud Base Height
CDA* DCL Clearance Echoback
CDOContinuous Descent Operations
CDRConditional Route
CFCourse to a fix
CFMU* Central Flow Management Unit
CHChannel
CHCK* Chocks
CHGModification (message type designator)
CIDINCommon ICAO data interchange network
- A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
C - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
CLCentre line
CLBRCalibration
CLDCloud
CLD* Departure clearance uplink message
CLRClear(s) or cleared to... or clearance
CMCentimetre
CMA* Centro de Meteorologia Aeronáutica
CNLFlight plan cancellation (message type designator)
CODE* ICAO Aircraft Address in alphanumerical of six hexadecimal characters format
COMCommunications
CONCConcrete
CONSContinuous
COORDCoordinates
COPChange-over point
CPDLCController-pilot data link communications
CPLCurrent flight plan (message type designator)
CPVM-AERO* Centro de Previsão e Vigilância Meteorológica para a aeronáutica
CR* Cross Sections
CR* Change Request
CRCCyclic redundancy check
CRC* Control and Reporting Centre
CRZCruise
CSCall sign
CSF* Communication Support Facility
CTAControl area
CTCContact
CTLControl
CTOT* Calculated Take-off Time
CTRControl zone
CVRCockpit voice recorder
CWYClearway
D - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
D...Danger area (followed by identification)
DADecision altitude
DAT* Data link
DCL* Data link departure clearance
DCTDirect (in relation to flight plan clearances and type of approach)
DCPCDirect controller-pilot communications
DECDecember
DEGDegrees
DEPDepart or departure
DEPDeparture (message type designator)
DES* De-suspension Message
DESTDestination
DFDirection finding
DISTDistance
DLADelay or delayed
DLADelay (message type designator)
DLE* En-route delay or holding
DLICData link initiation capability
DLM* Data link mandate
DMEDistance measuring equipment
DNM* Directorate Network Management
(EUROCONTROL)
DOC* Document
DOFDate of Flight (YYMMDD)
DTGDate-time group
DVORDoppler VOR
DVORTAC* DVOR and TACAN Combination
E - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
EEast or eastern longitude
EAD* European AIS Database
EASA* European Aviation Safety Agency
EATExpected approach time
EC* European Community
ECAC* European Civil Aviation Conference
EETEstimated elapsed time
EGNOSEuropean Geostationary Navigation Overlay System
EGPWS* Enhanced Ground Proximity Warning System
ELBAEmergency location beacon - aircraft
ELEVElevation
ELRExtra long range
ELTEmergency locator transmitter
EN* English
ENDStop-end (related to RVR)
ENREn route
ENRCEnroute Chart
EOBTEstimated off-block time
EPNdB* Effective perceived noise in decibels
EQPTEquipment
ERR* Error Message
ESEEast-south-east
ESTEstimate or estimated or estimate (message type designator)
ETAEstimated time of arrival or estimating arrival
ETDEstimated time of departure or estimating departure
ETFMS* Enhanced Tactical Flow Management System
ETOEstimated time over significant point
ETOT* Estimated Take-off Time
EU* European Union
EUR* European Region
EUROCONTROL* European Organisation for the Safety of Air Navigation
EVEvery
EXTDExtend or extending or extended
F - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
FACourse from a fix to an altitude
FAA* Federal Aviation Agency
FAFFinal approach fix
FALFacilitation of international air transport
FAM* Flight Activation Monitoring
FANS* Future Air Navigation Systems
FAPFinal approach point
FAP* Força Aérea Portuguesa (Portuguese Air Force)
FASFinal approach segment
FATOFinal approach and take-off area
FAXFacsimile transmission
FCSTForecast
FCTFriction coefficient
FEBFebruary
FFR* Fire Fighting
FFS* Fire Fighting Service
FICFlight information centre
FIRFlight information region
FISFlight information service
FLFlight level
FLGFlashing
FLS* Flight Suspension Message
FLTCKFlight check
FLWFollow(s) or following
FM* Modulated Frequency
FMFrom
FMCFlight management computer
FMD* Former CFMU Flow Management Division
FMP* Flow Management Position
FMSFlight management system
FNAFinal approach
FPLFlight plan
FOSA* Flight Operations Safety Assessment
FRA* Free Route Airspace
FREQFrequency
FRIFriday
FROP* Final Approach Roll-Out Point
FSM* Flight system update link message
FSTD* Flight Simulation Training Device
FTFeet (dimensional unit)
G - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
GGreen
GAGo ahead, resume sending (to be used in AFS as a procedure signal)
GAGeneral aviation
GAMA* Gabinete de Investigação de Acidentes Marítimos e da Autoridade para a Meteorologia Aeronáutica
GAMETArea forecast for low-level flights
GAT* General Air Traffic
GENGeneral
GEOGeographic or true
GH* Ground Handling
GIMFA* Grupo de Informação Meteorológica da Força Aérea (Air Force MET Information Group)
GMCGround movement chart (followed by name/title)
GNDGround
GNSSGlobal navigation satellite system
GPGlide path
GPAGlide path angle
GPIAAF* Gabinete de Prevenção e Investigação de Acidentes com Aeronaves e de Acidentes Ferroviários
GPSGlobal positioning system
GPUGround Power Unit
GPWSGround Proximity Warning System
GRHail
GRF* Global reporting format
GRASSGrass landing area
GSSmall hail and/or snow pellets
GSGround Speed
GUNDGeoid undulation
H - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
h* Hour
H24Continuous day and night service
HAZMAT* Hazardous Material
HEL* Helicopter or Heliport
HEMS* Hospital Emergency Medical Service
HFHigh frequency [3 000 to 30 000 kHz]
HGTHeight or height above
HJSunrise to sunset
HLAHigh Level Airspace
HLDGHolding
HMHolding/racetrack to a manual termination
HNSunset to sunrise
HOService available to meet operational requirements
HOLHoliday
HOSPHospital aircraft
HPAHectopascal
HRHours
HSService available during hours of scheduled operations
HUMHumanitarian
HXNo specific working hours
I - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
IACInstrument approach chart (followed by name/title)
IAFInitial approach fix
IAPInstrument Approach Procedure
IASIndicated airspeed
IATA* International Air Transport Association
IBNIdentification beacon
ICAOInternational Civil Aviation Organization
IDIdentifier or identify
IDENTIdentification
IFIntermediate approach fix
IFPS* Integrated Initial Flight Plan Processing System
IFPU* Integrated Initial Flight Plan Processing Unit
IFPZ* IFPS Zone
IFRInstrument flight rules
ILSInstrument landing system
IMInner marker
IMCInstrument meteorological conditions
INAInitial approach
INBDInbound
INFOInformation
INOPInoperative
INSInertial navigation system
INTIntersection
INTLInternational
INTSTIntensity
IPMA* Instituto Português do Mar e da Atmosfera
IRSInertial reference system
IRU* Inertial reference unit
ITC* Inclusive Tour Charter Flight
J - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
JAA* Joint Aviation Authorities
JANJanuary
JULJuly
JUNJune
K - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
KGKilograms
KHZKilohertz
KIASKnots indicated airspeed
KMKilometres
KTKnots
L - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
LLeft (Preceded by runway identification)
LLocator (see LM, LO)
LATLatitude
LCN* Load Classification Number
LDALanding distance available
LDGLanding
LDILanding direction indicator
LFLow frequency (30 to 300 KHz)
LGTLight or lighting
LGTDLighted
LIHLight intensity high
LILLight intensity low
LIMLight intensity medium
LMLocator, middle
LMTLocal mean time
LNAVLateral navigation (to be pronounced “EL-NAV”)
LOLocator, outer
LoA* Letter of agreement
LOCLocalizer
LONGLongitude
LORANLORAN (long range air navigation system)
LP* Localizer Performance
LPVLocalizer performance with vertical guidance
LRGLong range
LVLLevel
LVPLow Visibility Procedures
LVO* Low Visibility Operation
M - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
MMach number (followed by figures)
MMetres (preceded by figures)
MAGMagnetic
MAPAeronautical maps and charts
MAPTMissed approach point
MARMarch
MARSA* Military Assumes Responsibility for Separation of Aircraft
MATFMissed approach turning fix
MAXMaximum
MAYMay
MCTA* Military Control Area
MCTRMilitary Control Zone
MCWModulated continuous wave
MDAMínimum descent altitude
MEAMínimum enroute altitude
MEDEVACMedical Evacuation Flight
MEHTMinimum, eye height over threshold (for visual approach slope indicator systems)
MELMinimum Equipment List
METMeteorological or meteorology
METARAviation routine weather report (in aeronautical meteorological code)
MFMedium frequency (300 to 3 000 khz)
MHAMinimum Holding Altitude
MHZMegahertz
MIDMid-point (related to RVR)
MILMilitary
MINMinutes
MLAT* Multilateration
MLSMicrowave landing system
MMMiddle marker
MNMMinimum
MNPSMinimum navigation performance specifications
MNPSAMinimum navigation performance specifications airspace
MONMonday
MSMinus
MSAMinimum sector altitude
MSAWMinimum Safe Altitude Warning
MSLMean sea level
MSSRMonopulse secondary surveillance radar
MTOMMaximum take-off mass
MTOW* Maximum take-off  weight
MWOMeteorological watch office
N - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
NNorth or northern latitude
N/A* Not Applicable
NAC* Navigation accuracy category
NATNorth Atlantic
NATSPG* North Atlantic Systems Planning Group
NAVNavigation
NAVAIDNavigation Aid
NDBNon-directional radio beacon
NENorth-east
NIC* Navigation integrity category
NILNone or I have nothing to send to you
NMNautical miles
NNWNorth-north-west
NOC* National OPMET Centre
NOFInternational NOTAM office
NOTAMA notice distributed by means of telecommunication containing information concerning the establishment, condition or change in any aeronautical facility, service, procedure or hazard, the timely knowledge of which is essential to personnel concerned with flight operations
NOTAMCCancelling NOTAM
NOTAMNNew NOTAM
NOTAMRReplacing NOTAM
NOVNovember
NPANon-precision approach
NRNumber
NS* Non-schedule
NTLNational
NUCp* Navigation Uncertainty Category for Position
NVO* Normal Visibility Operations
NWNorth-west
O - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
OACOceanic area control centre
OBSTObstacle
OCAObstacle clearance altitude
OCAOceanic control area
OCD* Oceanic Clearance Delivery
OCHObstacle Clearance Height
OCL* Obstacle Clearance Limit
OCL* Oceanic Clearance
OCTOctober
OFZObstacle free zone
OKWe agree or it is correct (to be used in AFS as a procedure signal)
OLDIOn-line data interchange
OMOuter marker
OPMETOperational meteorological (information)
OPROperator or operate or operative or operating or operational
OPSOperations
ORGN* Originator of the flight plan
OTR* Other
OTSOrganized track system
OUBDOutbound
OWAFS* Operations without assigned fixed speed
P - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
P* Personal Consultation
P* Prognostic Upper Air Chart
P* Private
P* Provided
PALSPrecision approach lighting system (specify category)
PANSProcedures for air navigation services
PAPIPrecision approach path indicator
PARPrecision approach radar
PATCPrecision approach terrain chart (followed by name/title)
PAXPassenger(s)
PBNPerformance-based navigation
PCNPavement classification number
PDGProcedure design gradient
PERPerformance
PERMPermanent
PIBPre-flight information bulletin
PL*Abbreviated Plain Language Texts
PNPrior notice required
POBPersons on board
POS* Position Report
PPRPrior permission required
PSPlus
PT* Portuguese
PTNProcedure turn
PWRPower
Q - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
QDMMagnetic Heading (zero wind)
QDRMagnetic bearing
QFEAtmospheric pressure at aerodrome elevation (or at runway threshold)
QNHAltimeter sub-scale setting to obtain elevation when on the ground
R - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
RRight (preceded by runway designation number to identify a parallel runway)
RRed
RReceived (acknowledgement of receipt) (to be used in AFS as a procedure signal)
R...Restricted area (followed by identification)
R...Runway followed by figures in METAR/SPECI
R...Radial (from VOR followed by three figures)
RACRules of the air and air traffic services
RAD * Route Availability Document
RADAR* Radio Detection and Ranging
RAGRunway arresting gear
RALT* Route Alternative
RAIMReceiver autonomous integrity monitoring
RCCRescue coordination centre
RCD* Request for enroute clearance downlink
RCFRadio communication failure (message type designator)
RCR* Runway condition report
RCLLRunway centre line light(s)
RCPRequired communication performance
RDHReference Datum Height (for ILS)
RDLRadial
RDORadio
REA* Ready Message
REGRegistration
REPReport or reporting or reporting point
REQRequest or requested
RESARunway end safety area
RET* Rapid Exit Taxiway
RETIL* Rapid Exit Taxiway Indicator Lights
RFConstant radius arc to a fix
RFF * Rescue and Fire Fighting
RFFSRescue and Fire Fighting Services
RFP* Replacement Flight Plan (related to ATFM)
RIB* Rigid Inflatable Boat
RIFReclearance in flight
RMKRemark
RNAV(to be pronounced “AR-NAV”) Area navigation
RNPRequired Navigation Performance
RNP-AR* Required Navigation Performance - Authorization Required
ROCRate of climb
RP* Recommended Practice
RRPRerouting Proposal Message
RSCRescue sub-centre
RTERoute
RTFRadiotelephone
RTIL* Runway Threshold Identification Lights
RVRRunway visual range
RVSMReduced Vertical Separation Minimum
RWYRunway
S - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
s* Seconds
SSouth or southern latitude
S* Surface Analysis (Current Chart)
S* Schedule
SALSSimple approach lighting system
SAM* Slot Allocation Message
SARSearch and rescue
SATSaturday
SATCOMSatellite communication (used only when referring generally to both voice and data satellite communication or only data satellite communication)
SATEL* Satellite Image
SATVOICESatellite Voice communication
SBSouthbound
SBA* Aerodrome brigade service
SBASSpace Based Augmentation System
SBSLCI* Basic service of rescue and firefighting
SDFStep Down fix
SESouth-east
SECSeconds
SEL* Selcal Code
SELCALSelective calling system
SEPSeptember
SERA* Standardised European Rules of the Air
SFCSurface
SIDStandard instrument departure
SIGMETInformation concerning en-route weather and other phenomena in the atmosphere that may affect the safety of aircraft operations
SIGWX* Significant weather
SIL* Surveillance integrity level
SMA* Schedule Movement Advice
SIP* Slot Improvement Proposal Message
SITA* Société Internationale des Telecommunications Aeronautiques
SIWLSingle isolated wheel load
SLC* Slot Cancellation Message
SMCSurface movement control
SMRSurface movement radar
SNOWTAMA special series NOTAM notifying the presence or removal of hazardous conditions due to snow, ice, slush or standing water associated with snow, slush and ice on the movement area, by means of a specific format
SOP* Standard operating procedure
SPA* Slot Improvement Proposal Acceptance Message
SPECIAviation selected special weather report (in aeronautical meteorological code)
SPECIALSpecial meteorological report (in abbreviated plain language)
SRSunrise
SRASurveillance radar approach
SRJ* Slot Improvement Proposal Rejection Message
SRM* Slot Revision Message
SRRSearch and rescue region
SSSunset
SSESouth-south-east
SSRSecondary surveillance radar
SSTSupersonic transport
SSWSouth-south-west
STARStandard instrument arrival
STSStatus
SUN Sunday
SUPSupplement (AIP Supplement)
SUPPSRegional supplementary procedures
SUR* Surveillance Equipment
SVCService (message type only)
SWSouth-west
SWH* Significant Weather High Chart
SWM* Significant Weather Medium Chart
SWM* Sip Wanted Message
SWYStopway
SYNOP* Surface Synoptic Observations
T - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
TTrue (preceded by a bearing to indicate reference to True North)
T* Telephone
T-VASIST-Visual Approach Slope Indicator System
TAATerminal arrival Altitude
TACANUHF tactical air navigation aid
TACT* CFMU Tactical
TAFAerodrome forecast
TALT* Take-off alternate aerodrome(s)
TASTrue airspeed
TAWS* Terrain Awareness and Warning System
TBN* To Be Notified
TCAS* Traffic alert and collision avoidance system
TCHThreshold crossing height
TCP* Transfer Control Point
TDZTouchdown zone
TELTelephone
TERPS* Terminal Procedures
TFTrack to fix
TFCTraffic
TGLTouch-and-go landing
TGSTaxiing guidance system
THRThreshold
THRUThrough
THUThursday
TILUntil
TKOFTake-off
TLOFTouchdown and lift-off area
TMATerminal control area
TOBT* Target Off-Block Time
TODATake-off distance available
TOGA* Take-off Go Around
TORATake-off run available
TRTrack
TRATemporary reserved airspace
TRMZ* Transponder Radio Mandatory Zone
TSAT* Target Start-Up Approval Time
TUETuesday
TWRAerodrome control tower or aerodrome control
TWYTaxiway
TYPType of aircraft
U - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
UFNUntil further notice
UHFUltra high frequency [300 to 3 000 MHz]
UIRUpper flight information region
ULMUltra Light motorized Aircraft
UNHCR* United Nations High Commissioner for Refugees
UNLUnlimited
UPR* User-preferred route
UTCCoordinated Universal Time
V - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
VACVisual approach chart (followed by name/title)
VALC* Visual Approach and Landing Chart
VAR* Magnetic variation
VASISVisual approach slope indicator systems
VET* Veterinary
VFRVisual flight rules
VHFVery high frequency (30 to 300 MHz)
VISVisibility
VLRVery long range
VMHeading to a manual termination
VMCVisual meteorological conditions
VNAVVertical navigation (to be pronounced VEE_NAV)
VOLMETMeteorological information for aircraft in flight
VORVHF omnidirectional radio range
VORTACVOR and TACAN combination
VRBVariable
VSS* Visual segment surface
VTOF* Visual Take-off
W - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
WWest or western longitude
WWhite
W* Significant Weather Chart
WRNGWarning
WBARWing bar lights
WDIWind direction indicator
WEDWednesday
WGS-84World Geodetic System - 1984
WIDWidth or wide
WILCOWill comply
WIPWork in progress
WNWWest-North-West
WPTWay-point
WTWeight
WWWWorldwide web
WXWeather
WXRWeather Radar
Y - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z GLOSSARY OF TERMS
YYellow
YESYes (affirmative) (to be used in AFS as a procedure signal)