GEN 2.2  Abbreviations used in AIS publications

The abbreviations used in this AIP and in the general dissemination of information are extracted from ICAO Doc 8400. Abbreviations which differ from the ICAO abbreviations are shown with an asterisk (*).
(+) - When radiotelephony is used, the abbreviations and terms are transmitted as spoken words
(++) - When radiotelephony is used, the abbreviations and terms are transmitted using the individual letters in non-phonetic form
(#) - Signal for use in the teletypewriter service only

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
AAmber
A/AAir-to-air
A/GAir-to-ground
AAA(or AAB, AAC...etc., in sequence)
Amended meteorological message
(message type designator)
AADAssigned altitude deviation
AAEArresting Gear
AAIMAircraft autonomous integrity monitoring
AALAbove aerodrome level
AARAir to air refuelling
AARAir-to-Air Refuelling
ABCAdvance Booking Charter Flight
ABIAdvance boundary information
ABMAbeam
ABNAerodrome beacon
ABTAbout
ABVAbove
ACAltocumulus
ACARS(to be pronounced “AY-CARS”) Aircraft communication addressing and Reporting system(+)
ACASAirborne collision avoidance system
ACCArea control centre or area control(++)
ACCIDNotification of an aircraft accident
ACFTAircraft
ACKAcknowledge
ACLAltimeter check location
ACNAircraft classification number
ACPAcceptance (message type designator)
ACPTAccept or accepted
ACTActive or activated or activity
ADAerodrome
ADAAdvisory area
ADCAerodrome chart
ADDNAddition or additional
ADEPAirport of Departure
ADESAirport of Destination
ADEXPATS Data Exchange Presentation
ADFAutomatic direction-finding equipment(++)
ADIZ(to be pronounced “AY-DIZ”) Air defence identification zone(+)
ADJAdjacent
ADOAerodrome office (specify service)
ADRAdvisory route
ADSThe address (when this abbreviation is used to request a repetition, the question mark (IMI) precedes the abbreviation, e.g. IMI ADS) (to be used in AFS as a procedure signal)
ADS-BAutomatic dependent surveillance - broadcast(++)
ADS-CAutomatic dependent surveillance - contract(++)
ADSUAutomatic dependent surveillance unit
ADVSAdvisory service
ADZAdvise
AESAircraft earth station
AFILFlight plan filed in the air
AFISAerodrome flight information service
AFMYes or affirm or affirmative or that is correct
AFSAeronautical fixed service
AFTAfter... (time or place)
AFTNAeronautical fixed telecommunication network(++)
AGAAerodromes, air routes and ground aids
AGLAbove ground level
AGNAgain
AICAeronautical information circular
AIDCAir traffic services interfacility data communications
AIMAeronautical information management
AIMATFM Information Message
AIPAeronautical Information Publication
AIRACAeronautical Information Regulation And Control
AIREPAir-report(+)
AIRMETInformation concerning en-route weather phenomena which may affect the safety of low-level aircraft operations(+)
AIRPROXAircraft Proximity
AISAeronautical Information Services
ALAAlighting area
ALERFAAlert phase(+)
ALRAlerting (message type designator)
ALRSAlerting service
ALSApproach lighting system
ALSFApproach Lighting System with Sequence Flashing Lights
ALTAltitude
ALTNAlternate or alternating (light alternates in colour)
ALTNAlternate (aerodrome)
AMAArea minimum altitude
AMCAirspace Management Cell
AMDAmend or amended (used to indicate amended meteorological message; message type designator)
AMDTAmendment (AIP Amendment)
AMOSAerodrome Meteorological Observing System
AMSAeronautical mobile service
AMSLAbove mean sea level
AMSSAeronautical mobile satellite service
ANCAeronautical chart - 1:500 000 (followed by name/title)
ANCSAeronautical navigation chart - small scale (followed by name/title and scale)
ANMATFM Notification Message
ANPAir Navigation Plan
ANSAnswer
AOAircraft Operator
AOCAerodrome obstacle chart (followed by type and name/title)
APAirport
APAPI(to be pronounced “AY-PAPI”) Abbreviated precision approach path indicator(+)
APCHApproach
APDCAircraft parking/docking chart (followed by name title)
APISAircraft Parking and Information System
APNApron
APPApproach control office or approach control or approach control service
APRApril
APRXApproximate or approximately
APSGAfter passing
APUAuxiliary power unit
APVApproach procedure with vertical guidance
ARCArea chart
ARFORArea forecast (in aeronautical meteorological code)
ARNGArrange
AROAir traffic services reporting office
ARPAerodrome reference point
ARPAir-report (message type designator)
ARQAutomatic error correction
ARRArrival (message type designator)
ARRArrive or arrival
ARSSpecial air-report (message type designator)
ARSAAreas Requiring Special Attention
ARSTArresting (specify (part of) aircraft arresting equipment)
ARTArticle
ASAltostratus
ASAPAs soon as possible
ASCAscend to or ascending to
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
ASPEEDGAirspeed gain
ASPEEDLAirspeed loss
ASPHAsphalt
ATAt (followed by time at which weather change is forecast to occur)
AT-VASIS(to be pronounced “AY-TEE-VASIS”)(+)
Abbreviated T visual approach slope indicator system
ATAActual time of arrival(++)
ATCAir traffic control (in general)(++)
ATCSMACAir traffic control surveillance minimum altitude chart (followed by name/title)
ATDActual time of departure(++)
ATFMAir traffic flow management
ATISAutomatic terminal information service(+)
ATMAir traffic management
ATMAutomatic Teller Machine
ATNAeronautical telecommunication network
ATPAt... (time or place)
ATSAir traffic services
ATTNAttention
ATZAerodrome traffic zone
AUGAugust
AUPAirspace use Plan
AUTHAuthorized or authorization
AUTOAutomatic
AUWAll up weight
AUXAuxiliary
AVBLAvailable or availability
AVGAverage
AVGASAviation gasoline(+)
AWOSAutomated weather observation system
AWTAAdvise at what time able
AWYAirway
AZMAzimuth
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
BBlue
B-RNAVBasic Area Navigation
BABraking action
BAKType of  Arresting Gear
BARO-VNAVBarometric vertical navigation (to be pronounced “BAA-RO-VEE-NAV“)(+)
BASECloud base(+)
BCFGFog patches
BCNBeacon (aeronautical ground light)
BCSTBroadcast
BCUBird Control Unit
BDRYBoundary
BECMGBecoming
BFRBefore
BIRDTAMNOTAM Reporting Bird Hazard
BKNBroken
BLBlowing (followed by DU=dust, SA=sand or SN=snow)
BLDGBuilding
BLOBelow clouds
BLWBelow...
BOMBBombing
BRMist
BRFShort (used to indicate the type of approach desired or required)
BRGBearing
BRKGBraking
BSCommercial broadcasting station
BTLBetween layers
BTNBetween
BUFRBinary universal form for the representation of meteorological data
BYDBeyond
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
CCentre (runway identification)
CDegrees Celsius (Centigrade)
CCharts
CACourse to an altitude
CAACivil aviation authority or civil aviation administration
CARCaribbean
CASAComputer Assisted Slot Allocation
CATCategory
CATClear air turbulence
CAVOK(to be pronounced “KAV-OH-KAY”) Visibility, cloud and present weather better than prescribed values or conditions(+)
CB(to be pronounced “CEE BEE”) Cumulonimbus(++)
CBHCloud Base Height
CCcirrocumulus
CCA(or CCB, CCC... etc., in sequence) Corrected meteorological messages
CCOContinuous climb operations
CDCandela
CDNCoordination (message type designator)
CDOContinuous descent operations
CDRConditional Route
CEUCentral Executive Unit
CFChange frequency to...
CFCourse to a fix
CFMConfirm or I confirm (to be used in AFS as a procedure signal)
CGLCircling guidance light(s)
CHChannel
CHThis is a channel-continuity-check of transmission to permit comparison of your record of channel-sequence numbers of messages received on the channel (to be used in AFS as a procedure signal)(#)
CHCKChocks
CHEMChemical
CHGModification (message type designator)
CICirrus
CIDINCommon ICAO data interchange network(+)
CIVCivil
CKCheck
CLCentre line
CLAClear type of ice formation
CLBRCalibration
CLDCloud
CLDClearance Delivery
CLGCalling
CLIMB-OUTClimb-out area
CLRClear(s) or cleared to... or clearance
CLRDRunway(s) cleared (used in METAR/SPECI)
CLSDClose or closed or closing
CMCentimetre
CMBClimb to or climbing to
CMPLCompletion or completed or complete
CNLCancel or cancelled
CNLFlight plan cancellation (message type designator)
CNSCommunications, navigation and surveillance
CODEICAO Aircraft Address in form alphanumerical of six hexadecimal characters
COFAAir Force Operational Command
COMCommunications
CONCConcrete
CONDCondition
CONSContinuous
CONSTConstruction or constructed
CONTContinue(s) or continued
COORCoordinate or coordination
COORDCoordinates
COPChange-over point
CORCorrect or correction or corrected (used to indicate corrected meteorological message; message type designator)
COTAt the coast
COVCover or covered or covering
CPDLCController-pilot data link communications(++)
CPLCurrent flight plan (message type designator)
CRCross Sections
CRAMConditional Route Availability Message
CRCCyclic redundancy check
CRCControl and Reporting Centre
CRMCollision risk model
CRPCompulsory reporting point
CRZCruise
CSCall sign
CSCirrostratus
CSFCommunication Support Facility
CTAControl area
CTAMClimb to and maintain
CTCContact
CTLControl
CTNCaution
CTOTCalculated Take-off Time
CTRControl zone
CUCumulus
CUFCumuliform
CUSTCustoms
CVRCockpit voice recorder
CWContinuous wave
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
DDownward (tendency in RVR during previous 10 minutes)
DDanger area (followed by identification)
D-ATIS(to be pronounced “DEE-ATIS”) Data link automatic terminal information service(+)
D-VOLMETData link VOLMET
DADecision altitude
DATData Link
DCDDouble channel duplex
DCKGDocking
DCLClearance Delivery Service
DCPDatum crossing point
DCPCDirect controller-pilot communications
DCSDouble channel simplex
DCTDirect (in relation to flight plan clearances and type of approach)
DEFrom (used to precede the call sign of the calling station) (to be used in AFS as a procedure signal)
DECDecember
DEGDegrees
DEPDepart or departure
DEPDeparture (message type designator)
DEPODeposition
DERDeparture End of the Runway
DESDescend to or descending to
DESTDestination
DETRESFA Distress phase(+)
DEVDeviation or deviating
DFDirection finding
DFDRDigital flight data recorder
DFTIDistance from touchdown indicator
DGSDocking Guidance System
DHDecision height
DIFDiffuse
DISTDistance
DIVDivert or diverting
DLADelay or delayed
DLADelay (message type designator)
DLICData link initiation capability
DLYDaily
DMEDistance measuring equipment(++)
DNGDanger or dangerous
DOCDocument
DOFDate of Flight
DOMDomestic
DPDew point temperature
DPTDepth
DRDead reckoning
DRLow drifting (followed by DU=dust, SA=sand or SN=snow)
DRGDuring
DSDuststorm
DSBDouble sideband
DTAMDescend to and maintain
DTGDate-time group
DTHRDisplaced runway threshold
DTRTDeteriorate or deteriorating
DTWDual tandem wheels
DUDust
DUCDense upper cloud
DUPEThis is a duplicate message (to be used in AFS as a procedure signal)(#)
DURDuration
DVORDoppler VOR
DVORTACDVOR and TACAN Combination
DWDual wheels
DZDrizzle
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
EEast or eastern longitude
EADEuropean AIS Database
eAIPElectronic Aeronautical Information Publication
EATExpected approach time
EBEastbound
ECEuropean Community
ECACEuropean Civil Aviation Conference
EDAElevation differential area
EDTOExtended diversion time operations
EEEError (to be used in AFS as a procedure signal)(#)
EETEstimated elapsed time
EFCExpect further clearance
EFIS(to be pronounced “EE-FIS”) Electronic flight instrument system(+)
EFISElectronic flight instrument system (to be pronounced “EE-FIS”)(+)
EGNOS(to be pronounced “EGG-NOS) European geostationary navigation overlay service(+)
EHFExtremely high frequency (30 000 to 300 000 MHz)
ELBAEmergency location beacon - aircraft(+)
ELEVElevation
ELRExtra long range
ELTEmergency locator transmitter
EMEmission
EMBDEmbedded in a layer (to indicate cumulonimbus embedded in layers of other clouds)
EMERGEmergency
ENEnglish
ENDStop-end (related to RVR)
ENEEast-north-east
ENGEngine
ENREn route
ENRCEnroute chart (followed by name/title)
EOBTEstimated off-block time
EPNdBEffective perceived noise in decibels
EQPTEquipment
ESEEast-south-east
ESTEstimate or estimated or estimation (message type designator)
ETAEstimated time of arrival or estimating arrival(++)
ETDEstimated time of departure or estimating departure
ETFMSEnhanced Tactical Flow Management System
ETOEstimated time over significant point
ETOTEstimated Take-off Time
EUEuropean Union
EUREuropean Region
EUR RODEXEuropean regional OPMET data exchange
EVEvery
EVSEnhanced vision system
EXCExcept
EXCLExcluded
EXERExercises or exercising or to exercise
EXPExpect or expected or expecting
EXTExtension
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
FFixed
FACourse from a fix to an altitude
FACFacilities
FAFFinal approach fix
FALFacilitation of international air transport
FAMFlight Activation Monitoring
FANSFuture Air Navigation Systems
FAPFinal approach point
FASFinal approach segment
FATOFinal approach and take-off area
FAXFacsimile transmission
FBLLight (used to indicate the intensity of weather phenomena, interference or static reports, e.g. FBL RA = light rain)
FCFunnel cloud (tornado or water spout)
FCSTForecast
FCTFriction coefficient
FDPSFlight data processing system
FEBFebruary
FEWFew
FFSFire Fighting Service
FGFog
FICFlight information centre
FIRFlight information region(++)
FISFlight information service
FISAAutomated flight information service
FLFlight level
FLDField
FLGFlashing
FLRFlares
FLSFlight Suspension Message
FLTFlight
FLTCKFlight check
FLUCFluctuating or fluctuation or fluctuated
FLWFollow(s) or following
FLYFly or flying
FMModulated Frequency
FMFrom
FMFrom (followed by time weather change is forecast to begin)
FMCourse from a fix to manual termination (used in navigation database coding)
FMCFlight management computer
FMDFormer NM Flow Management Division
FMPFlow Management Position
FMSFlight management system(++)
FMUFlow management unit
FNAFinal approach
FPAPFlight path alignment point
FPLFlight plan
FPMFeet per minute
FPRFlight plan route
FRFuel remaining
FRAFree route airspace(*)
FREQFrequency
FRIFriday
FRNGFiring
FRONTFront (relating to weather)(+)
FROSTFrost (used in aerodrome warnings)(+)
FRQFrequent
FSLFull stop landing
FSSFlight service station
FSTFirst
FTFeet (dimensional unit)
FTEFlight technical error
FTPFictitious threshold point
FTTFlight technical tolerance
FUSmoke
FZFreezing
FZDZFreezing drizzle
FZFGFreezing fog
FZRAFreezing rain
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
GGreen
GVariations from the mean wind speed (gusts) (followed by figures in METAR/SPECI and TAF)
G/AGround-to-air
G/A/GGround-to-air and air-to-ground
GAGo ahead, resume sending (to be used in AFS as a procedure signal)
GA General aviation
GAGANGPS and geostationary earth orbit augmented navigation(+)
GAINAirspeed or headwind gain
GAMETArea forecast for low-level flights
GARPGBAS azimuth reference point
GATGeneral Air Traffic
GBAS(to be pronounced “GEE-BAS”) Ground-based augmentation system(+)
GCAGround controlled approach system or ground controlled approach(++)
GENGeneral
GEOGeographic or true
GESGround earth station
GLDGlider
GLONASS(to be pronounced “GLO-NAS”) Global orbiting navigation satellite system(++)
GLSGBAS landing system (++)
GMCGround movement chart (followed by name/title)
GNDGround
GNDCKGround check
GNSSGlobal navigation satellite system(++)
GOVGovernment
GPGlide path
GPAGlide path angle
GPIPGlide path intercept point
GPSGlobal positioning system(++)
GPUGround power unit
GPWSGround proximity warning system(++)
GRHail
GRASS(to be pronounced “GRASS”) Ground-based regional augmentation system(+)
GRASSGrass landing area
GRIBProcessed meteorological data in the form of grid point values expressed in binary form (in meteorological code)
GRVLGravel
GSGround speed
GSSmall hail and/or snow pellets
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
HHigh pressure area or the centre of high pressure
HHour
HHeight
H...Significant wave height (followed by figures in METAR/SPECI)
H24Continuous day and night service
HAHolding/racetrack to an altitude
HAPIHelicopter approach path indicator
HBNHazard beacon
HCHHeliport crossing height
HDFHigh frequency direction-finding station
HDGHeading
HELHelicopter
HEMSHospital Emergency Medical Service
HFHigh frequency [3 000 to 30 000 kHz](++)
HFHolding/racetrack to a fix
HGTHeight or height above
HIROHigh Intensity Runway Operation
HJSunrise to sunset
HLDGHolding
HLPHeliport
HLSHeliport landing site
HMHolding/racetrack to a manual termination
HNSunset to sunrise
HOService available to meet operational requirements
HOLHoliday
HOSPHospital aircraft
HPAHectopascal
HQHeadquarters
HRHours
HSService available during hours of scheduled operations
HTHigh Tension
HTAHelicopter Training Area
HUDHead-up display
HUMHumanitarian
HURCNHurricane
HVDFHigh and very high frequency direction- finding stations (at the same location)
HVYHeavy
HVYHeavy (used to indicate the intensity of weather phenomena,e.g. HVY RA = heavy rain)
HXNo specific working hours
HYRHigher
HZHaze
HZHertz (cycle per second)
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
IACInstrument approach chart (followed by name/title)
IAFInitial approach fix
IAOIn and out of clouds
IAPInstrument approach procedure
IARIntersection of air routes
IASIndicated airspeed
IATAInternational Air Transport Association
IBNIdentification beacon
ICAOInternational Civil Aviation Organization
ICDInterface Control Document
ICEIcing
IDIdentifier or identify
IDENTIdentification(+)
IFIntermediate approach fix
IFFIdentification friend/foe
IFPSIntegrated Initial Flight Plan Processing System
IFPUIntegrated Initial Flight Plan Processing Unit
IFPZIFPS Zone
IFRInstrument flight rules(++)
IGAInternational general aviation
ILSInstrument landing system(++)
IMInner marker
IMCInstrument meteorological conditions(++)
IMGImmigration
IMIInterrogation sign (question mark) (to be used in AFS as a procedure signal)
IMPRImprove or improving
IMTImmediate or immediately
INAInitial approach
INBDInbound
INCIn cloud
INCERFAUncertainty phase(+)
INCORPIncorporated
INDIndicator
INFOInformation(+)
INOPInoperative
INPIf not possible
INPRIn progress
INSInertial navigation system
INSTLInstall or installed or installation
INSTRInstrument
INTIntersection
INTLInternational
INTRGInterrogator
INTRPInterrupt or interruption or interrupted
INTSFIntensify or intensifying
INTSTIntensity
IRIce on runway
IRSInertial reference system
ISAInternational standard atmosphere
ISBIndependent sideband
ISOLIsolated
ITCInclusive 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
JAAJoint Aviation Authorities
JANJanuary
JETJet
JTSTJet stream
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
KGKilograms
KHZKilohertz
KIASKnots indicated airspeed
KMKilometres
KMHKilometres per hour
KPAKilopascal
KTKnots
KWKilowatts
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
LLeft (preceded by runway designation number to identify a parallel runway)
LLitre
LLocator
LLow pressure area or the centre of low pressure
LAMLogical acknowledgement (message type designator)
LANInland
LATLatitude
LBPounds (Weight)
LCALocal or locally or location or located
LCNLoad classification number
LDALanding distance available
LDAHLanding distance available, helicopter
LDGLanding
LDILanding direction indicator
LENLength
LFLow frequency (30 to 300 KHz)
LGTLight or lighting
LGTDLighted
LIHLight intensity high
LILLight intensity low
LIMLight intensity medium
LINELine (used in SIGMET)
LMLocator, middle
LMTLocal mean time
LNAVLateral navigation (to be pronounced “EL-NAV”)(+)
LNGLong (used to indicate the type of approach desired or required)
LOLocator, outer
LOCLocalizer
LONGLongitude
LORANLORAN (long range air navigation system)(+)
LOSSAirspeed or headwind loss
LPVLocalizer performance with vertical guidance
LRThe last message received by me was...
(to be used in AFS as a procedure signal)
LRGLong range
LSLast message sent by me, was...or Last message was... (to be used in AFS as a procedure signal)
LTALower control area
LTDLimited
LTPLanding threshold point
LVLight and variable (relating to wind)
LVELeave or leaving
LVLLevel
LVOLow Visibility Operation
LVPLow Visibility Procedures
LYRLayer or layered
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
MMach number (followed by figures)
MMetres (preceded by figures)
MMinimum value of runway visual range (followed by figures in METAR/SPECI)
MAAMaximum authorized altitude
MAGMagnetic
MAHFMissed approach holding fix
MAINTMaintenance
MALSMedium Intensity Approach Lighting System
MAPAeronautical maps and charts
MAPTMissed approach point
MARAt sea
MARMarch
MATFMissed approach turning fix
MATZMilitary aerodrome traffic zone
MAXMaximum
MAYMay
MBSTMicroburst
MCAMinimum crossing altitude
MCTAMilitary control area
MCTRMilitary control zone
MCWModulated continuous wave
MDAMinimum descent altitude
MDFMedium frequency direction-finding station
MDHMinimum descent height
MEAMinimum en-route altitude
MEDEVACMedical evacuation flight
MEHTMinimum eye height over threshold (for visual approach slope indicator systems)
METMeteorological or meteorology(+)
MET REPORTLocal routine meteorological report (in abbreviated plain language)
METARAerodrome routine meteorological report (in meteorological code)(+)
MFMedium frequency (300 to 3 000 khz)
MHAMinimum holding altitude
MHDFMedium and high frequency direction-finding stations (at the same location)
MHVDFMedium, high and very high frequency direction-finding stations (at the same location)
MHZMegahertz
MIDMid-point (related to RVR)
MIFGShallow fog
MILMilitary
MINMinutes
MIPSMilitary Instrument Procedures
MISMiscellaneous
MISMissing... (transmission identification)
(to be used in AFS as a procedure signal)
MKRMarker radio beacon
MLSMicrowave landing system(++)
MMMiddle marker
MNMMinimum
MNPSMinimum navigation performance specifications
MNTMonitor or monitoring or monitored
MNTNMaintain
MOAMilitary operating area
MOCMinimum obstacle clearance (required)
MOCAMinimum obstacle clearance altitude
MODModerate (used to indicate the intensity of weather phenomena, interference or stactic reports, e.g. MODRA=moderate rain)
MONAbove mountains
MONMonday
MOPSMinimum operational performance standards(+)
MOTNEMeteorological Operational Telecommunications Network Europe
MOVMove or moving or movement
MPHStatute Miles per Hour
MPSMetres per second
MRAMinimum reception altitude
MRGMedium range
MRPATS/MET reporting point
MSMinus
MSAMinimum sector altitude
MSAS(to be pronounced “EM-SAS”) Multi-functional transport satellite (MTSAT) satellite-based augmentation system(+)
MSAWMinimum Safe Altitude Warning
MSGMessage
MSLMean sea level
MSRMessage... (transmission identification) has been misrouted (to be used in AFS as a procedure signal)(#)
MSSRMonopulse secondary surveillance radar
MTMountain
MTOMMaximum take-off mass
MTOWMaximum Take-off  Weight
MTUMetric units
MTWMountain waves
MVDFMedium and very high frequency direction- finding stations (at the same location)
MWOMeteorological watch office
MXMixed type of ice formation (white and clear)
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
NNo distinct tendency (in RVR during previous 10 minutes)
NNorth or northern latitude
NADPNoise abatement departure procedure
NASCNational AIS system centre(+)
NATNorth Atlantic
NATSPGNorth Atlantic Systems Planning Group
NAVNavigation
NAVAIDNavigation aid
NBNorthbound
NBFRNot before
NCNo change
NCDNo cloud detected (used in automated METAR/SPECI)
NDBNon-directional radio beacon(++)
NDVNo directional variations available (used in automated METAR/SPECI)
NENorth-east
NEBNorth-eastbound
NEGNo or negative or permission not granted or that is not correct
NGTNight
NILNone or I have nothing to send to you(+)
NMNetwork Manager
NMNautical miles
NMLNormal
NNNo name, unnamed
NNENorth-north-east
NNWNorth-north-west
NONo (negative) (to be used in AFS as a procedure signal)
NOFInternational NOTAM office
NONSTDNon-standard
NOSIGNo significant change (used in trend-type landing forecasts)(+)
NOTAMNotice 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
NOZNormal operating zone(++)
NPANon-precision approach
NRNumber
NRHNo reply heard
NSNimbostratus
NSNon-schedule
NSCNil significant cloud
NSENavigation system error
NSWNil significant weather
NTLNational
NTZNo transgression zone(++)
NVONormal Visibility Operations
NWNorth-west
NWBNorth-westbound
NXTNext
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
O/ROn request
OACOceanic area control centre
OASObstacle assessment surface
OBSObserve or observed or observation
OBSCObscure or obscured or obscuring
OBSTObstacle
OCAObstacle clearance altitude
OCAOceanic control area
OCCOcculting (light)
OCHObstacle clearance height
OCLObstacle clearance limit
OCNLOccasional or occasionally
OCSObstacle clearance surface
OCTOctober
OFZObstacle free zone
OGNOriginate (to be used in AFS as a procedure signal)
OHDOverhead
OISObstacle identification surface
OKWe agree or lt is correct (to be used in AFS as a procedure signal)
OLDIOn-line data interchange(+)
OMOuter marker
OPAOpaque, white type of ice formation
OPCControl indicated is operational control
OPMETOperational meteorological (information)(+)
OPNOpen or opening or opened
OPROperator or operate or operative or operating or operational
OPSOperations(+)
OPSDNM Operations Division
ORDOrder
OSVOcean station vessel
OTLKOutlook (used in SIGMET messages for volcanic ash and tropical cyclones)
OTPOn top
OTROther
OTSOrganized track system
OUBDOutbound
OVCOvercast
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
PPrognostic upper air chart
PMaximum value of wind speed or runway visual range (followed by figures in METAR/SPECI and TAF)
PProhibited area (followed by identification)
PAPrecision approach
PALSPrecision approach lighting system (specify category)
PANSProcedures for air navigation services
PAPIPrecision approach path indicator(+)
PARPrecision approach radar(++)
PARLParallel
PATCPrecision approach terrain chart (followed by name/title)
PAXPassenger(s)
PBCPerformance-based communication
PBNPerformance-based navigation
PBSPerformance-based surveillance
PCDProceed or proceeding
PCLPilot-controlled lighting
PCNPavement classification number
PCTPer cent
PDCPre-departure clearance(++)
PDGProcedure design gradient
PDUSPrimary Data User Station
PERPerformance
PERMPermanent
PIBPre-flight information bulletin
PJEParachute jumping exercise
PLIce pellets
PLAPractice low approach
PLVLPresent level
PNPrior notice required
PNRPoint of no return
PODust/sand whirls (dust devils)
POBPersons on board
POSPosition Report
POSSPossible
PPIPlan position indicator
PPRPrior permission required
PPSNPresent position
PRFGAerodrome partially covered by fog
PRIPrimary
PRKGParking
PROBProbability(+)
PROCProcedure
PROPPropeller
PROVProvisional
PRPPoint-in-space reference point
PSPlus
PSGPassing
PSNPosition
PSPPierced steel plank
PSRPrimary surveillance radar(++)
PSYSPressure system(s)
PTPortuguese
PTNProcedure turn
PTSPolar track structure
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
QDLDo you intend to ask me for a series of bearings? or I intend to ask you for a series of bearings (to be used in radiotelegraphy as a Q Code)
QDMMagnetic heading (zero wind)(++)
QDRMagnetic bearing
QFEAtmospheric pressure at aerodrome elevation (or at runway threshold)(++)
QFUMagnetic orientation of runway
QGEWhat is my distance to your station? or Your distance to my station is (distance figures and units) (to be used in radiotelegraphy as a Q Code)
QJHShall I run my test tape/a test sentence? or Run your test tape/a test sentence (to be used in AFS as a Q Code)
QNHAltimeter sub-scale setting to obtain elevation when on the ground(++)
QSPWill you relay to... free of charge? or I will relay to... free of charge (to be used in AFS as a Q Code)
QTAShall I cancel telegram number...? or Cancel telegram number... (to be used in AFS as a Q Code)
QTETrue bearing
QTFWill you give me the position of my station according to the bearings taken by the D/F stations which you control? or The position of your station according to the bearings taken by the DIF stations that I control was... latitude... longitude (or other indication of position), class... at... hours (to be used in radiotelegraphy as a Q Code)
QUADQuadrant
QUJWill you indicate the TRUE track to reach you? or The TRUE track to reach me is... degrees at... hours (to be used in radiotelegraphy as a Q Code)
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
RRight (Preceded by runway designation number to identify a parallel runway)
RRate of turn
RRed
RRestricted area (followed by identification)
RRunway (followed by figures in METAR/SPECI
RRight (runway identification)
RReceived (acknowledgement of receipt) (to be used in AFS as a procedure signal)
RRadial from VOR (followed by three figures)
RARain
RAResolution advisory
RACRules of the air and air traffic services
RADRoute Availability Document
RADARRadio Detection and Ranging
RAFCRegional area forecast centre
RAGRagged
RAGRunway arresting gear
RAIRunway alignment indicator
RAIMReceiver autonomous integrity monitoring(+)
RALTRoute Alternative
RASCRegional AIS system centre(+)
RASSRemote altimeter setting source
RBRescue boat
RBKReadback
RCAReach cruising altitude
RCAReach cruising altitude
RCCRescue coordination centre
RCFRadiocommunication failure (message type designator)
RCHReach or reaching
RCLRunway centre line
RCLOceanic clearance request
RCLLRunway centre line light(s)
RCLRRecleared
RCPRequired communication performance(++)
RDHReference datum height (for ILS)
RDLRadial
RDORadio
RDOACTRadioactive
RERecent (used to qualify weather phenomena, e.g. RERA = recent rain)
REAReady message
RECReceive or receiver
REDLRunway edge light(s)
REFReference to... or refer to...
REGRegistration
REJRejected
RENLRunway end light(s)
REPReport or reporting or reporting point
REQRequest or requested
REQReclearance request
RERTERe-route
RESARunway end safety area
RESPBYRespond by (Time out to give a response)
RETRapid exit taxiway
RETILRapid exit taxiway indicator lights
RFConstant radius arc to a fix
RFFRescue and fire fighting
RFFSRescue and fire fighting services
RFPReplacement flight plan (related to ATFM)
RGRange (lights)
RHCRight-hand circuit
RIFReclearance in flight
RIMERime (used in aerodrome warnings)(+)
RLReport leaving
RLARelay to
RLCERequest level change en route
RLLSRunway lead-in lighting system
RLNARequest level not available
RLSReport Level or Speed
RMKRemark
RNAV(to be pronounced “AR-NAV”) Area navigation(+)
RNGRadio range
RNPRequired navigation performance(++)
ROBEXRegional OPMET bulletin exchange (scheme)(+)
ROCRate of climb
RODRate of descent
ROFORRoute forecast (in aeronautical meteorological code)
RONReceiving only
RPRecommended Practice
RPDSReference path data selector
RPEReported Estimated
RPIRadar position indicator(++)
RPLRepetitive flight plan
RPLCReplace or replaced
RPSRadar position symbol
RPTRepeat or I repeat (to be used in AFS as a procedure signal)(+)
RQRequest (to be used in AFS as a procedure signal)
RQMNTSRequirements
RQPRequest flight plan (message type designator)
RQSRequest supplementary flight plan (message type designator)
RRReport reaching
RRA(or RRB, RRC... etc., in sequence) Delayed meteorological message
(message type designator)
RRPRerouting proposal message
RSCRescue sub-centre
RSCDRunway surface condition
RSPResponder beacon
RSPRequired surveillance performance (++)
RSREn-route surveillance radar
RSSRoot sum square
RTDDelayed (used to indicate delayed meteorological message; message type designator)
RTERoute
RTFRadiotelephone
RTGRadiotelegraph
RTHLRunway threshold light(s)
RTNReturn or returned or returning
RTODAHRejected take-off distance available, helicopter
RTSReturn to service
RTTRadioteletypewriter
RTZLRunway touchdown zone light(s)
RUTStandard regional route transmitting frequencies
RVRescue vessel
RVARadar vectoring area
RVRRunway visual range(++)
RVSMReduced Vertical Separation Minimum [300 m (1000 ft) between FL290 and FL410] (++)
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
SSeconds
SSouth or southern latitude
SState of the sea (followed by figures in METAR/SPECI)
SSurface Analysis (Current Chart)
SSchedule
SASand
SALSSimple approach lighting system
SAMSlot Allocation Message
SANSanitary
SARSearch and rescue
SARPsStandards and Recommended Practices [ICAO]
SATSaturday
SATCOMSatellite communication(+)
SATVOICESatellite voice communication
SBSouthbound
SBAS(to be pronounced “ESS-BAS”) Satellite-based augmentation system(+)
SCStratocumulus
SCTScattered
SDStandard deviation
SDBYStand by
SDFStep down fix
SESouth-east
SEASea (used in connection with sea-surface temperature and state of the sea)
SEBSouth-eastbound
SECSeconds
SECSpecial event charter flight
SECNSection
SECTSector
SELSelcal Code
SELCALSelective calling system(+)
SEPSeptember
SERService or servicing or served
SEVSevere (used e.g. to qualify icing and turbulence reports)
SFCSurface
SGSnow grains
SGLSignal
SHShower (followed by
RA = rain,
SN = snow,
PL = ice pellets,
GR = hail,
GS = small hail and/or snow pellets or
combinations thereof e.g. SHRASN= showers of rain and snow)
SHFSuper high frequency (3 000 to 30 000 MHz)
SIInternational system of units.
SIDStandard instrument departure(+)
SIFSelective identification feature
SIGSignificant
SIGMETInformation concerning en-route weather and other phenomena in the atmosphere that may affect the safety of aircraft operations(+)
SIGWXSignificant weather
SIMULSimultaneous or simultaneously
SIPSlot improvement proposal message
SITASociété Internationale des Telecommunications Aeronautiques
SIWLSingle isolated wheel load
SKCSky clear
SKEDSchedule or scheduled
SLCSlot Cancellation Message
SLPSpeed limiting point
SLWSlow
SMASchedule movement advice
SMCSurface movement control
SMRSurface movement radar
SNSnow
SNOCLOAerodrome closed due to snow (used in METAR/SPECI)
SNOWTAMSpecial 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(+)
SOCStart of climb
SPASlot improvement proposal acceptance message
SPECIAerodrome special meteorological report (in meteorological code)
SPECIALLocal special meteorological report (in abbreviated plain language)(+)
SPISpecial position indicator
SPLSupplementary flight plan (message type designator)
SPOCSAR point of contact
SPOTSpot wind(+)
SQSquall
SQKSSR Assignment
SQLSquaIl line
SRSunrise
SRASurveillance radar approach
SRESurveillance radar element of precision approach radar system
SRGShort range
SRJSlot Improvement Proposal Rejection Message
SRMSlot Revision Message
SRRSearch and rescue region
SRYSecondary
SSSandstorm
SSSunset
SSBSingle sideband
SSESouth-south-east
SSRSecondary surveillance radar(++)
SSTSupersonic transport
SSWSouth-south-west
STStratus
STAStraight-in approach
STARStandard instrument arrival(+)
STDStandard
STFStratiform
STNStation
STNRStationary
STOLShort take-off and landing
STSStatus
STWLStopway light(s)
SUBJSubject to
SUN Sunday
SUPSupplement (AIP Supplement)
SUPPSRegional supplementary procedures
SVCService (message type only)
SVCBLServiceable
SWSouth-west
SWBSouth-westbound
SWHSignificant weather high chart
SWMSignificant weather medium chart
SWYStopway
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
TTemperature
TTrue (preceded by a bearing to indicate reference to True North)
TTelephone
T-VASIST Visual Approach Slope Indicator System
TATransition altitude
TATraffic advisory
TA/HTurn at an altitude/height
TAATerminal arrival altitude
TACANUHF tactical air navigation aid(+)
TACTNM Tactical
TAFAerodrome forecast (in meteorological code)(+)
TAILTail wind(+)
TARTerminal area surveillance radar
TASTrue airspeed
TAXTaxiing or taxi
TBNTo be notified
TCTropical cyclone
TCACTropical cyclone advisory centre
TCAS RATraffic alert and collision avoidance system resolution advisory (to be pronounced “TEE-CAS-AR-AY”)(+)
TCHThreshold crossing height
TCPTransfer Control Point
TCUTowering cumulus
TDOTornado
TDZTouchdown zone
TDZETouchdown zone elevation
TECRTechnical reason
TELTelephone
TEMPOTemporary or temporarily(+)
TENDTrend forecast(+)
TERTerrain
TERPSTerminal procedures
TFTrack to fix
TFCTraffic
TGLTouch-and-go landing
TGSTaxiing guidance system
THRThreshold
THRUThrough
THUThursday
TIBATraffic information broadcast by aircraft(+)
TILUntil(+)
TIPUntil past... (followed by place)
TKOFTake-off
TLTill (followed by time by which weather change is forecast to end)
TLOFTouchdown and lift-off area
TMATerminal control area(++)
TNMinimum temperature (followed by figures in TAF)
TNATurn altitude
TNHTurn height
TOTo... (followed by place)
TOBTTarget of block time
TOCTop of climb
TODATake-off distance available
TODAHTake-off distance available helicopter
TOPCloud top(+)
TORATake-off run available
TOXToxic
TPTurning point
TRTrack
TRATemporary reserved airspace
TRANSTransmits or transmitter
TRENDTrend forecast(+)
TRGTraining
TRLTransition level
TROPTropopause
TSThunderstorm (in aerodrome reports and forecasts, TS used alone means thunder heard but no precipitation at the aerodrome)
TSThunderstorm (followed by RA=RAIN, SN=snow, PL=ice pellets, GR=hail, GS=small hail and/or snow pellets or combinations thereof e.g. TSRASN=thunderstorm with rain and snow)
TSATemporary Segregated Area(+)
TSUNAMITsunami (used in aerodrome warnings)
TTTeletypewriter
TUETuesday
TURBTurbulence
TVORTerminal VOR
TWRAerodrome control tower or aerodrome control
TWYTaxiway
TXMaximum temperature (followed by figures in TAF)
TXLTaxilane
TXTText (when the abbreviation is used to request a repetition, the question mark (IMI) Precedes the abbreviation, eg. IMI TXT) (to be used in AFS as a procedure signal)
TYPType of aircraft
TYPHTyphoon
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
UUpward (tendency in RVR during previous 10 minutes)
U/SUnserviceable
UAUnmanned aircraft
UABUntil advised by...
UACUpper area control centre
UARUpper air route
UASUnmanned aircraft system
UDFUltra high frequency direction-finding station
UFNUntil further notice
UHDTUnable higher due traffic
UHFUltra high frequency [300 to 3 000 MHz] (++)
UICUpper information centre
UIRUpper flight information region(++)
ULMUltra Light motorized Aircraft
ULRUltra long range
UNAUnable
UNAPUnable to approve
UNLUnlimited
UNRELUnreliable
UPUnidentified precipitation (used in automated METAR/SPECI)
UTAUpper control area
UTCCoordinated Universal Time(++)
UTCWCoordinated Universal Time - Winter
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
VVariations from the mean wind direction (preceded and followed by figures in METAR/SPECI, e.g. 350V070)
VAVolcanic ash
VAHeading to an altitude
VAACVolcanic ash advisory centre
VACVisual approach chart (followed by name/title)
VALIn valleys
VANRunway control van
VARMagnetic variation
VARVisual-aural radio range
VASISVisual approach slope indicator systems
VATValue-added tax
VCVicinity of the aerodrome (followed by FG=fog, FC=funnelcloud, SH=shower, PO=dust/sand whirls, BLDU=blowing dust, BLSA=blowing sand, BLSN = blowing snow, DS = duststorm or SS = sandstorm, e. g. VCFG = vicinity fog)
VCYVicinity
VDFVery high frequency direction-finding station
VDPVisual descend point
VERVertical
VETVeterinary
VFRVisual flight rules (++)
VHFVery high frequency (30 to 300 MHz)(++)
VIHeading to an intercept
VIPVery important person(++)
VISVisibility
VLFVery low frequency [3 to 30 KHz]
VLRVery long range
VMHeading to a manual termination
VMCVisual meteorological conditions(++)
VNAVVertical navigation (to be pronounced VEE-NAV)(++)
VOL...Volume (followed by I, II...)
VOLMETMeteorological information for aircraft in flight(+)
VORVHF omnidirectional radio range(++)
VORTACVOR and TACAN combination(++)
VOTVOR airborne equipment test facility
VPAVertical path angle
VPTVisual manoeuvre with prescribed track
VRBVariable
VSABy visual reference to the ground
VSPVertical speed
VTFVector to final
VTOLVertical take-off and landing
VVVertical visibility (followed by figures in METAR/SPECI and TAF)
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
WWest or western longitude
WWhite
WWidth or wide
WSignificant Weather Chart
WSea-surface temperature (followed by figures in METAR/SPECI)
WAASWide area augmentation system(+)
WACWorld Aeronautical Chart - ICAO 1: 1 000 000 (followed by name/title)
WAFCWorld area forecast centre
WBWestbound
WBARWing bar lights
WDIWind direction indicator
WDSPRWidespread
WEDWednesday
WEFWith effect from or effective from
WGS-84World Geodetic System - 1984
WIWithin
WIDWidth or wide
WIEWith immediate effect or effective immediately
WILCOWill comply(+)
WINDWind
WINTEMForecast upper wind and temperature for aviation
WIPWork in progress
WKNWeaken or weakening
WNWWest-north-west
WOWithout
WPTWay-point
WRNGWarning
WSWind shear
WSPDWind speed
WSWWest-south-west
WTWeight
WTSPTWaterspout
WWWWorldwide web
WXWeather
WXRWeather radar
X - 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
XCross
XBARCrossbar (of approach lighting system)
XNGCrossing
XSAtmospherics
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
YYellow
YCZYellow caution zone (runway lighting)
YESYes (affirmative) (to be used in AFS as a procedure signal)
YRYour
Z - 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
ZCoordinated Universal Time (in meteorological messages)