|
*Abbreviations marked with an asterisk are either different from or not contained in ICAO Doc 8400.
|
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.
|
A
|
|
A
|
Alpha* |
A
|
Amber |
A
|
Amperes* |
A
|
Auto-tuned NAVAID* |
AA
|
All after...* |
AAA
|
(or AAB, AAC... etc., in sequence) Amended meteorological message (message type designator) |
A/A
|
Air-to-air |
AAL
|
Above aerodrome level |
AAD
|
Assigned altitude deviation |
AAR
|
Air to air refuelling |
AAIM
|
Aircraft autonomous integrity monitoring |
AB
|
All before...* |
ABI
|
Advance boundary information |
ABM
|
Abeam |
ABN
|
Aerodrome beacon |
ABT
|
About |
ABV
|
Above |
AC
|
Advisory Circular* |
AC
|
Alternate Current* |
AC
|
Altocumulus |
ACARS
|
† (to be pronounced “AY-CARS”) Aircraft communication addressing and reporting system |
ACAS
|
† (to be pronounced “AY-CAS”) Airborne collision avoidance system |
ACC
|
‡ Area control centre or area control |
ACCID
|
Notification of an aircraft accident |
ACFT
|
Aircraft |
ACK
|
Acknowledge |
ACL
|
Altimeter check location |
ACN
|
Aircraft classification number |
ACP
|
Acceptance (message type designator) |
ACPT
|
Accept or accepted |
ACT
|
Active or activated or activity |
AD
|
Aerodrome |
ADA
|
Advisory area |
ADC
|
Aerodrome chart |
ADDN
|
Addition or additional |
ADF
|
‡ Automatic direction-finding equipment |
ADIZ
|
† Air defence identification zone |
ADJ
|
Adjacent |
ADR
|
Advisory route |
ADS
|
Automatic dependent surveillance* |
ADS
|
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-B
|
‡ Automatic Dependent Surveillance — broadcast |
ADS-C
|
‡ Automatic dependent surveillance — contract |
ADSU
|
Automatic dependent surveillance unit |
ADVS
|
Advisory service |
ADZ
|
Advise |
AES
|
Aircraft earth station |
AFC
|
Area forecast centre* |
AFIL
|
Flight plan filed in the air |
AFIS
|
Aerodrome flight information service |
AFM
|
Yes or affirm or affirmative or that is correct |
AFS
|
Aeronautical fixed service |
AFT...
|
After (followed by time or place) |
AFTN
|
‡ Aeronautical fixed telecommunication network |
A/G
|
Air-to-ground |
AGA
|
Aerodromes, air routes and ground aids |
AGL
|
Above ground level |
AGN
|
Again |
AIC
|
Aeronautical information circular |
AIDC
|
Air traffic services interfacility data communications |
AIM
|
Aeronautical information management |
AIP
|
Aeronautical information publication |
AIRAC
|
Aeronautical information regulation and control |
AIREP
|
† Air-report |
AIRMET
|
† Information concerning en-route weather phenomena which may affect the safety of low-level aircraft operations |
AIS
|
Aeronautical information services |
ALA
|
Alighting area |
ALERFA
|
† Alert phase |
ALR
|
Alerting (message type designator) |
ALS
|
Approach lighting system |
ALT
|
Altitude |
ALTN
|
Alternate or alternating (light alternates in colour) |
ALTN
|
Alternate (aerodrome) |
AMD
|
Amend or amended |
AMDT
|
Amendment (AIP Amendment) |
AMS
|
Aeronautical mobile service |
AMSL
|
Above mean sea level |
AMSS
|
Aeronautical mobile satellite service |
ANC...
|
Aeronautical chart — 1:500 000 (followed by name/title) |
ANCS...
|
Aeronautical navigation chart — small scale (followed by name/title and scale) |
ANS
|
Answer |
AO
|
Aircraft operator |
AOC...
|
Aerodrome obstacle chart (followed by type and name/title) |
AP
|
Airport |
APAPI
|
† (to be pronounced “AY-PAPI”) Abbreviated precision approach path indicator |
APCH
|
Approach |
APDC...
|
Aircraft parking/docking chart (followed by name/title) |
APN
|
Apron |
APP
|
Approach control office or approach control or approach control service |
APR
|
April |
APRX
|
Approximate or approximately |
APSG
|
After passing |
APU
|
Auxiliary power unit |
APV
|
Approach procedure with vertical guidance |
AR
|
End of transmission* |
ARC
|
Area chart |
ARFF
|
Aircraft Rescue and Fire Fighting* |
ARFOR
|
Area forecast* (in aeronautical meteorological code) |
ARMET
|
Forecast upper wind and temperature at specified points* (in aeronautical meteorological code) |
ARNG
|
Arrange |
ARO
|
Air traffic services reporting office |
ARP
|
Aerodrome reference point |
ARP
|
Air-report (message type designator) |
ARQ
|
Automatic error correction |
ARR
|
Arrival (message type designator) |
ARR
|
Arrive or arrival |
ARS
|
Special air-report (message type designator) |
ARST
|
Arresting (specify (part of) aircraft arresting equipment) |
AS
|
Altostratus |
AS
|
Wait* |
ASAP
|
As soon as possible |
ASC
|
Ascent to or ascending to |
ASDA
|
Accelerate-stop distance available |
ASE
|
Altimetry system error |
ASHTAM
|
Special series 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 |
ASPH
|
Asphalt |
AT...
|
At (followed by time at which weather change is forecast to occur) |
ATA
|
‡ Actual time of arrival |
ATC
|
‡ Air traffic control (in general) |
ATCSMAC…
|
Air traffic control surveillance minimum altitude chart (followed by name/title) |
ATD
|
‡ Actual time of departure |
ATFM
|
Air traffic flow management |
ATIS
|
† (to be pronounced “AY-TIS”) Automatic terminal information service |
ATM
|
Air traffic management |
ATN
|
Aeronautical telecommunication network |
ATP…
|
At (followed by time or place) |
ATS
|
Air traffic services |
ATTN
|
Attention |
AT-VASIS
|
† (to be pronounced “AY-TEE-VASIS”) Abbreviated T visual approach slope indicator system |
ATZ
|
Aerodrome traffic zone |
AUG
|
August |
AUTH
|
Authorized or authorization |
AUTO
|
Automatic |
AUW
|
All up weight |
AUX
|
Auxiliary |
AVASIS
|
Abbreviated visual approach slope indicator system* |
AVBL
|
Available or availability |
AVG
|
Average |
AVGAS
|
† Aviation gasoline |
AWOS
|
Automated weather observation system |
AWTA
|
Advise at what time able |
AWY
|
Airway |
AZM
|
Azimuth |
|
B
|
|
B
|
Blue |
B
|
Bravo* |
BA
|
Braking action |
BARO-VNAV
|
† (to be pronounced “BAA-RO-VEENAV”) Barometric vertical navigation |
BASE
|
† Cloud base |
BCFG
|
Fog patches |
BCN
|
Beacon (aeronautical ground light) |
BCST
|
Broadcast |
BDRY
|
Boundary |
BECMG
|
Becoming |
BFR
|
Before |
BIRD
|
Reykjavik FIR OAC ACC FIC |
BKN
|
Broken |
BL...
|
Blowing (followed by DU = dust, SA = sand or SN = snow) |
BLDG
|
Building |
BLO
|
Below clouds |
BLW
|
Below... |
BOMB
|
Bombing |
BR
|
Mist |
BRF
|
Short (used to indicate the type of approach desired or required) |
BRG
|
Bearing |
BRKG
|
Braking |
BS
|
Commercial broadcasting station |
BTL
|
Between layers |
BTN
|
Between |
BUFR
|
Binary universal form for the representation of meteorological data |
|
C
|
|
C
|
Centre (preceded by runway designation number to identify a parallel runway (...C)) |
C
|
Degrees Celsius (Centigrade) |
CA
|
Course to an altitude |
CAA
|
Civil aviation authority or civil aviation administration |
CAT
|
Category |
CAT
|
Clear air turbulence |
CAVOK
|
† (to be pronounced “KAV-OH-KAY”)
Visibility, cloud and present weather better than prescribed values or conditions
|
CB
|
‡ Cumulonimbus (to be pronounced “CEE BEE”) |
CBA
|
Cross Border Area* |
CC
|
Cirrocumulus |
CCA
|
(or CCB, CCC... etc., in sequence) Corrected meteorological message (message type designator) |
CCO
|
Continuous climb operations |
CD
|
Candela |
CDN
|
Co-ordination (message type designator) |
CDO
|
Continuous descent operations |
CDR
|
Conditional route |
CF
|
Change frequency to... |
CF
|
Course to a fix |
CFM
|
Confirm or I confirm |
CGL
|
Circling guidance light(s) |
CH
|
Channel |
CH#
|
This 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) |
CHEM
|
Chemical |
CHG
|
Modification (message type designator) |
CI
|
Cirrus |
CIDIN
|
† Common ICAO data interchange network |
CIT
|
Near or over large towns* |
CIV
|
Civil |
CK
|
Check |
CL
|
Centre line |
CLA
|
Clear type of ice formation |
CLBR
|
Calibration |
CLD
|
Cloud |
CLG
|
Calling |
CLIMB-OUT
|
Climb-out area |
CLR
|
Clear(s) or cleared to... or clearance |
CLSD
|
Close or closed or closing |
CM
|
Centimetre |
CMB
|
Climb to or climbing to |
CMPL
|
Completion or completed or complete |
CNL
|
Cancel or cancelled |
CNL
|
Flight plan cancellation (message type designator) |
CNS
|
Communications, navigation and surveillance |
CNS
|
Continuous* |
COM
|
Communications |
CONC
|
Concrete |
COND
|
Condition |
CONS
|
Continuous |
CONST
|
Construction or constructed |
CONT
|
Continue or continued |
COOR
|
Coordinate or coordination |
COORD
|
Coordinates |
COP
|
Change-over point |
COR
|
Correct or corrected or correction
(used to indicate corrected meteorological message; message type designator)
|
COT
|
At the coast |
COV
|
Cover or covered or covering |
CP
|
General call to two or more specified stations* |
CPDLC
|
‡ Controller-pilot data link communications |
CPL
|
Current flight plan (message type designator) |
CRC
|
Cyclic redundancy check |
CRM
|
Collision risk model |
CRP
|
Compulsory reporting point |
CRZ
|
Cruise |
CS
|
Call sign |
CS
|
Cirrostratus |
CTA
|
Control area |
CTAM
|
Climb to and maintain |
CTC
|
Contact |
CTL
|
Control |
CTN
|
Caution |
CTR
|
Control zone |
CU
|
Cumulus |
CUF
|
Cumuliform |
CUST
|
Customs |
CVR
|
Cockpit voice recorder |
CW
|
Continuous wave |
CWY
|
Clearway |
|
D
|
|
D
|
Downward (tendency in RVR during previous 10 minutes) |
D...
|
Danger area (followed by identification) |
DA
|
Decision altitude |
D-ATIS
|
† Data link automatic terminal information service (to be pronounced “DEE-ATIS”) |
DCD
|
Double channel duplex |
DCKG
|
Docking |
DCP
|
Datum crossing point |
DCPC
|
Direct controller-pilot communications |
DCS
|
Double channel simplex |
DCT
|
Direct (in relation to flight plan clearances and type of approach) |
DE
|
From (used to precede the call sign of the calling station) (to be used in AFS as a procedure signal) |
DEC
|
December |
DEG
|
Degrees |
DENEB
|
Fog dispersal operations* |
DEP
|
Depart or departure |
DEP
|
Departure (message type designator) |
DEPO
|
Deposition |
DER
|
Departure end of the runway |
DES
|
Descend to or descending to |
DEST
|
Destination |
DETRESFA
|
† Distress phase |
DEV
|
Deviation or deviating |
DF
|
Direction finding |
DFDR
|
Digital flight data recorder |
DFTI
|
Distance from touchdown indicator |
DGPS
|
Differential global positioning system* |
DH
|
Decision height |
DIF
|
Diffuse |
DIST
|
Distance |
DIV
|
Divert or Diverting |
DLA
|
Delay (message type designator) |
DLA
|
Delay or delayed |
DLIC
|
Data link initiation capability |
DLY
|
Daily |
DLM
|
Data Link Manager* |
DME
|
‡ Distance measuring equipment |
DNG
|
Danger or dangerous |
DOF
|
Date of flight |
DOM
|
Domestic |
DP
|
Dew point temperature |
DPT
|
Depth |
DR
|
Dead reckoning |
DR...
|
Low drifting (followed by DU = dust, SA = sand or SN = snow) |
DRG
|
During |
DS
|
Duststorm |
DRSN
|
Low drifting snow* |
DSB
|
Double side-band |
DTAM
|
Descend to and maintain |
DTG
|
Date-time group |
DTHR
|
Displaced runway threshold |
DTRT
|
Deteriorate or deteriorating |
DTW
|
Dual tandem wheels |
DU
|
Dust |
DUC
|
Dense upper cloud |
DUPE
|
This is a duplicate message (to be used in AFS as a procedure signal) |
DUR
|
Duration |
D-VOLMET
|
Data link VOLMET |
DVOR
|
Doppler VOR |
DW
|
Dual wheels |
DZ
|
Drizzle |
|
E
|
|
E
|
East or eastern longitude |
EAT
|
Expected approach time |
EB
|
Eastbound |
EDA
|
Elevation differential area |
EDTO
|
Extended diversion time operations |
EEE#
|
Error (to be used in AFS as a procedure signal) |
EET
|
Estimated elapsed time |
EFC
|
Expect further clearance |
EFIS
|
† Electronic flight instrument system overlay service (to be pronounced “EE-FIS”) |
EGNOS
|
† European geostationary navigation (to be pronounced “EGG-NOS”) |
EHF
|
Extremely high frequency (30 000 to 300 000 MHz) |
ELBA
|
† Emergency location beacon - aircraft |
ELEV
|
Elevation |
ELR
|
Extra long range |
ELT
|
Emergency locator transmitter |
EM
|
Emission |
EMBD
|
Embedded in a layer (to indicate cumulonimbus embedded in layers of other clouds) |
EMERG
|
Emergency |
END
|
Stop-end (related to RVR) |
ENE
|
East-north-east |
ENG
|
Engine |
ENR
|
En route |
ENRC...
|
Enroute chart (followed by name/title) |
ENRT
|
En route* |
EOBT
|
Estimated off-block time |
EQN
|
Equatorial latitudes northern hemisphere |
EQPT
|
Equipment |
EQS
|
Equatorial latitudes southern hemisphere |
ER
|
Here... or herewith* |
ESE
|
East-south-east |
EST
|
Estimate or estimated or estimation (message type designator) |
ETA
|
‡ Estimated time of arrival or estimating arrival |
ETD
|
‡ Estimated time of departure or estimating departure |
ETO
|
Estimated time over significant point |
EUR RODEX
|
European regional OPMET data exchange |
EV
|
Every |
EXC
|
Except |
EXER
|
Exercises or exercising or to exercise |
EXP
|
Expect or expected or expecting |
EXTD
|
Extend or extending |
|
F
|
|
F
|
Fixed |
F
|
Degrees Fahrenheit* |
FA
|
Course from a fix to an altitude |
FAC
|
Facilities |
FAF
|
Final approach fix |
FAL
|
Facilitation of international air transport |
FANS
|
Future Air Navigation Systems* |
FAP
|
Final approach point |
FAS
|
Final approach segment |
FATO
|
Final approach and take-off area |
FAX
|
Facsimile transmission |
FBL
|
Light (used to indicate the intensity of weather phenomena, interference or static reports, e.g. FBL RA = light rain) |
FC
|
Funnel cloud |
FCST
|
Forecast |
FCT
|
Friction coefficient |
FDPS
|
Flight data processing system |
FEB
|
February |
FEW
|
Few |
FG
|
Fog |
FIC
|
Flight information centre |
FIR
|
‡ Flight information region |
FIS
|
Flight information service |
FISA
|
Automated flight information service |
FL
|
Flight level |
FLD
|
Field |
FLG
|
Flashing |
FLR
|
Flares |
FLT
|
Flight |
FLTCK
|
Flight check |
FLUC
|
Fluctuating or fluctuation or fluctuated |
FLW
|
Follow(s) or following |
FLY
|
Fly or flying |
FM
|
Course from a fix to manual termination (used in navigation database coding) |
FM
|
From |
FM...
|
From (followed by time at which weather change is forecast to begin) |
FMC
|
Flight management computer |
FMS
|
‡ Flight management system |
FMU
|
Flow management unit |
FNA
|
Final approach |
FOT
|
Units of English system* |
FPAP
|
Flight path alignment point |
FPL
|
Flight plan |
FPM
|
Feet per minute |
FPR
|
Flight plan route |
FR
|
Fuel remaining |
FREQ
|
Frequency |
FRI
|
Friday |
FRNG
|
Firing |
FRONT
|
† Front (relating to weather) |
FROST
|
† Frost (used in aerodrome warnings) |
FRQ
|
Frequent |
FSFE
|
FANS services front end* |
FSL
|
Full stop landing |
FSS
|
Flight service station |
FST
|
First |
FT
|
Feet (dimensional unit) |
FTE
|
Flight technical error |
FTP
|
Fictitious threshold point |
FTT
|
Flight technical tolerance |
FU
|
Smoke |
FZ
|
Freezing |
FZDZ
|
Freezing drizzle |
FZFG
|
Freezing fog |
FZRA
|
Freezing rain |
|
G
|
|
G
|
Golf* |
G
|
Green |
G
|
Wind Gusts* |
G...
|
Variations from the mean wind speed (gusts) (followed by figures in METAR/SPECI and TAF) |
G/A
|
Ground-to-air |
G/A/G
|
Ground-to-air and air-to-ground |
GA
|
General aviation |
GA
|
Go ahead, resume sending (to be used in AFS as a procedure signal) |
GAGAN
|
† GPS and geostationary earth orbit augmented navigation |
GAIN
|
Airspeed or headwind gain |
GAMET
|
Area forecast for low-level flights |
GARP
|
GBAS azimuth reference point |
GAT
|
General Air Traffic* |
GBAS
|
† Ground-based augmentation system (to be pronounced “GEE-BAS”) |
GCA
|
‡ Ground controlled approach system or ground controlled approach |
GEN
|
General |
GEO
|
Geographic or true |
GES
|
Ground earth station |
GLD
|
Glider |
GLONASS
|
† Global navigation satellite system (to be pronounced “GLO-NAS”) |
GLS
|
‡ GBAS landing system |
GMC...
|
Ground movement chart (followed by name/title) |
GMT
|
Greenwich mean time* |
GND
|
Ground |
GNDCK
|
Ground check |
GNSS
|
‡ Global nav. sat. system |
GOV
|
Government |
GP
|
Glide path |
GPA
|
Glide path angle |
GPIP
|
Glide path intercept point |
GPS
|
‡ Global positioning system |
GPU
|
Ground power unit |
GPWS
|
‡ Ground proximity warning system |
GR
|
Hail |
GRAS
|
† Ground-based regional augmentation system (to be pronounced “GRASS”) |
GP VHF
|
‡ General purpose very high frequency* |
GR
|
Hail or soft hail* |
GRAD
|
Minimum required Climb Gradient* |
GRADU
|
Gradual or gradually* |
GRASS
|
Grass landing area |
GRIB
|
Processed meteorological data in the form of grid point values expressed in binary form
(in meteorological code)
|
GRID
|
Processed meteorological data in the form of grid point values*
(in aeronautical meteorological code)
|
GRN
|
Green* |
GRVL
|
Gravel |
GS
|
Ground speed |
GS
|
Small hail and/or snow pellets |
GUND
|
Geoid undulation |
|
H
|
|
H
|
High pressure area or the centre of high pressure |
H...
|
Significant wave height (followed by figures in METAR/SPECI) |
H24
|
Continuous day and night service |
HA
|
Holding/racetrack to an altitude |
HAPI
|
Helicopter approach path indicator |
HBN
|
Hazard beacon |
HCH
|
Heliport crossing height |
HDF
|
High frequency direction-finding station |
HDG
|
Heading |
HEL
|
Helicopter |
HF
|
Holding/racetrack to a fix |
HF
|
‡ High frequency (3 000 to 30 000 kHz) |
HGT
|
Height or height above |
HJ
|
Sunrise to sunset |
HLA
|
High Level Airspace* |
HLDG
|
Holding |
HLP
|
Heliport |
HLS
|
Helicopter landing site |
HM
|
Holding/racetrack to a manual termination |
HN
|
Sunset to sunrise |
HNH
|
High latitudes northern hemisphere |
HO
|
Service available to meet operational requirements |
HOL
|
Holiday |
HOSP
|
Hospital aircraft |
HPA
|
Hectopascal |
HR
|
Hours |
HRP
|
Heliport reference point |
HS
|
Service available during hours of scheduled operations |
HSH
|
High latitudes southern hemisphere |
HUD
|
Head-up display |
HUM
|
Humanitarian |
HURCN
|
Hurricane |
HVDF
|
High and very high frequency direction-finding stations (at the same location) |
HVY
|
Heavy |
HVY
|
Heavy (used to indicate the intensity of weather phenomena, e.g. HVY RA = heavy rain) |
HX
|
No specific working hours |
HYR
|
Higher |
HZ
|
Haze |
HZ
|
Hertz (cycle per second) |
|
I
|
|
IAC...
|
Instrument approach chart (followed by name/title) |
IAF
|
Initial approach fix |
IAIP
|
Integrated Aeronautical Information Package* |
IAL
|
Instrument approach and landing chart* |
IAO
|
In and out of clouds |
IAP
|
Instrument approach procedure |
IAR
|
Intersection of air routes |
IAS
|
Indicated air speed |
IBN
|
Identification beacon |
ICAO
|
International Civil Aviation Organization |
ICE
|
Icing |
ID
|
Identifier or identify |
IDENT
|
† Identification |
IF
|
Intermediate approach fix |
IFF
|
Identification friend/foe |
IFR
|
‡ Instrument flight rules |
IGA
|
International general aviation |
ILS
|
‡ Instrument landing system |
IM
|
Inner marker |
IMC
|
‡ Instrument meteorological conditions |
IMG
|
Immigration |
IMI
|
Interrogation sign (question mark) (to be used in AFS as a procedure signal) |
IMPR
|
Improve or improving |
IMT
|
Immediate or immediately |
INA
|
Initial approach |
INBD
|
Inbound |
INC
|
In cloud |
INCERFA
|
† Uncertainty phase |
INCORP
|
Incorporated |
INFO
|
† Information |
INOP
|
Inoperative |
INP
|
If not possible |
INPR
|
In progress |
INS
|
Inches (dimensional unit)* |
INS
|
Inertial navigation system |
INSTL
|
Install or installed or installation |
INSTR
|
Instrument |
INT
|
Intersection |
INTER
|
Intermittent* |
INTL
|
International |
INTRG
|
Interrogator |
INTRP
|
Interrupt or interruption or interrupted |
INTSF
|
Intensify or intensifying |
INTST
|
Intensity |
IR
|
Ice on runway |
IRS
|
Inertial reference system |
ISA
|
International standard atmosphere |
ISB
|
Independent sideband |
ISOL
|
Isolated |
|
J
|
|
JAG
|
Jet arresting gear* |
JAN
|
January |
JM
|
Make a series of dashes if I may transmit* |
JM
|
Make a series of dots to stop my transmission* |
JRCC
|
Joint Rescue Coordination Centre* Björgunarstjórnstöð sjófarenda og loftfara* |
JTST
|
Jet stream |
JUL
|
July |
JUN
|
June |
|
|
K
|
|
K
|
Invitation to transmit* |
KA
|
Start-of-message signal in Morse telegraphy* |
KG
|
Kilograms |
KHZ
|
Kilohertz |
KIAS
|
Knots indicated airspeed |
KM
|
Kilometres |
KMH
|
Kilometres per hour |
KPA
|
Kilopascal |
KT
|
Knots |
KW
|
Kilowatts |
|
|
L
|
|
L
|
Left (preceded by runway designation number to identify a parallel runway (...L)) |
L
|
Litre |
L
|
Locator (see LM, LO) |
L
|
Low pressure area or the centre of low pressure |
LAM
|
Logical acknowledgement (message type designator) |
LAN
|
Inland |
LAT
|
Latitude |
LB
|
Pounds (weight)* |
LCA
|
Local or locally or location or located |
LCN
|
Load classification number* |
LDA
|
Landing distance available |
LDAH
|
Landing distance available, helicopter |
LDG
|
Landing |
LDI
|
Landing direction indicator |
LDIN
|
Lead-In Light System* |
LEFT
|
Left (direction of turn)* |
LEN
|
Length |
LF
|
Low frequency (30 to 300 kHz) |
LGT
|
Light or lighting |
LGTD
|
Lighted |
LIH
|
Light intensity high |
LIL
|
Light intensity low |
LIM
|
Light intensity medium |
LINE
|
Line (used in SIGMET) |
LLZ
|
Localizer* |
LM
|
Locator, middle |
LMT
|
Local mean time |
LNAV
|
† Lateral navigation (to be pronounced “EL-NAV”) |
LNG
|
Long (used to indicate the type of approach desired or required) |
LO
|
Locator, outer |
LOC
|
Localizer, Locally*, location* or located* |
LONG
|
Longitude |
LORAN
|
† LORAN (long range air navigation system) |
LOSS
|
Airspeed or headwind loss |
LPV
|
Localizer performance with vertical guidance |
LR
|
The last message received by me was... (to be used in AFS as a procedure signal) |
LRG
|
Long range |
LS
|
The last message sent by me was... or Last message was... (to be used in AFS as a procedure signal) |
LSQ
|
Line squall* |
LTA
|
Lower control area |
LTD
|
Limited |
LTP
|
Landing threshold point |
LTT
|
Land-line teletypewriter* |
LV
|
Light and variable (relating to wind) |
LVE
|
Leave or leaving |
LVL
|
Level |
LVP
|
Low visibility procedures |
LYR
|
Layer or layered |
|
M
|
|
M
|
Metres (preceded by figures (...M)) |
M...
|
Mach number (followed by figures) |
M...
|
Minimum value of runway visual range (followed by figures in METAR/SPECI) |
MAA
|
Minimum authorized altitude |
MAG
|
Magnetic |
MAHF
|
Missed approach holding fix |
MAINT
|
Maintenance |
MALS
|
Medium Intensity Approach Light System* |
MALSF
|
MALS with sequenced Flashing lights* |
MALSR
|
MALS with Runway alignment indicator* |
MAP
|
Aeronautical maps and charts |
MAPT
|
Missed approach point |
MAPt
|
Missed approach point* |
MAR
|
At sea |
MAR
|
March |
MAS
|
Manual Al simplex* |
MATF
|
Missed approach turning fix |
MATZ
|
Military aerodrome traffic zone |
MAX
|
Maximum |
MAY
|
May |
MB
|
Millibars* |
MBST
|
Microburst |
MC...
|
Multiple copy for delivery to... (number) addressees* |
MCA
|
Minimum crossing altitude |
MCTR
|
Military control zone |
MCW
|
Modulated continuous wave |
MDA
|
Minimum descent altitude |
MDF
|
Medium frequency direction-finding station |
MDH
|
Minimum descent height |
MEA
|
Minimum en-route altitude |
MEDEVAC
|
Medical evacuation flight |
MEHT
|
Minimum eye height over threshold |
MET
|
† Meteorological or meteorology |
MET REPORT
|
Local routine meteorological report (in abbreviated plain language) |
METAR
|
† Aerodrome routine meteorological report (in meteorological code) |
MF
|
Medium frequency (300 to 3000 kHz) |
MHA
|
Minimum holding altitude |
MHDF
|
Medium and high frequency direction-finding stations (at the same location) |
MHVDF
|
Medium, high and very high frequency direction-finding station (at the same location) |
MHZ
|
Megahertz |
MID
|
Mid-point (related to RVR) |
MIFG
|
Shallow fog |
MIL
|
Military |
MIN
|
Minutes |
MIS
|
Missing... (transmission identification) (to be used in AFS as a procedure signal) |
MKR
|
Marker radio beacon |
MLAT
|
Multilateration* |
MLS
|
‡ Microwave landing system |
MM
|
Middle marker |
MMMM
|
Connect to... stations (used in multiple transmission, followed by call signs of stations)* |
MNH
|
Middle latitudes northern hemisphere |
MNM
|
Minimum |
MNPS
|
Minimum navigation performance specifications |
MNT
|
Monitor or monitoring or monitored |
MNTN
|
Maintain |
MOA
|
Military operating area |
MOC
|
Minimum obstacle clearance (required) |
MOCA
|
Minimum obstacle clearance altitude |
MOD
|
Moderate (used to qualify icing, turbulence, interference, or static reports)* |
MOD
|
Moderate (used to indicate the intensity of weather phenomena, interference or static reports, e.g. MODRA = moderate rain) |
MON
|
Above mountains |
MON
|
Monday |
MOPS
|
† Minimum operational performance standards |
MOTNE
|
Meteorological Operational Telecommunications Network Europe* |
MOV
|
Move or moving or movement |
MPH
|
Statute miles per hour* |
MPS
|
Metres per second |
MRA
|
Minimum reception altitude |
MRG
|
Medium range |
MRP
|
ATS/MET reporting point |
MS
|
Minus |
MSA
|
Minimum safe altitude* |
MSA
|
Minimum sector altitude |
MSAS
|
† Multifunctional transport satellite (MTSAT) satellite-based augmentation system (to be pronounced “EM-SAS”) |
MSAW
|
Minimum safe altitude warning |
MSG
|
Message |
MSH
|
Middle latitudes southern hemisphere |
MSL
|
Mean sea level |
MSR
|
Message... (transmission identification) has been misrouted (to be used in AFS as a procedure signal) |
MSSR
|
Monopulse secondary surveillance radar |
MT
|
Mountain |
MTOM
|
Maximum take-off mass |
MTOW
|
Maximum Take-Off Weight |
MTU
|
Metric units |
MTW
|
Mountain waves |
MVDF
|
Medium and very high frequency direction-finding stations (at the same location) |
MWO
|
Meteorological watch office |
MX
|
Mixed type of ice formation (white and clear) |
|
N
|
|
N
|
No distinct tendency (in RVR during previous 10 minutes) |
N
|
North or northern latitude |
NADP
|
Noise abatement departure procedure |
NASC
|
† National AIS system centre |
NAT
|
North Atlantic |
NAV
|
Navigation |
NAVAID
|
Navigation aid |
NB
|
Northbound |
NBFR
|
Not before |
NC
|
No change |
NCD
|
No cloud detected (used in automated METAR/SPECI) |
ND
|
I am unable to deliver message... (filing number) addressed to aircraft... (identification): please notify message originator* |
NDB
|
‡ Non-directional radio beacon |
NDV
|
No directional variations available (used in automated METAR/SPECI) |
NE
|
North-east |
NEB
|
North-eastbound |
NEG
|
No or negative or permission not granted or that is not correct |
NEH
|
I am connecting you to a station which will accept traffic for the station you request* |
NGT
|
Night |
NIL
|
† None or I have nothing to send to you |
NM
|
Nautical miles |
NML
|
Normal |
NN
|
No name, unnamed |
NMOC
|
Network Manager Operations Centre* |
NNE
|
North-north-east |
NNW
|
North-north-west |
NO
|
No (negative) (to be used in AFS as a procedure signal) |
NOF
|
International NOTAM office |
NONSTD
|
Non-standard |
NOSIG
|
† No significant change (used in trend-type landing forecasts) |
NOTAM
|
† 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 |
NOTAMC
|
Cancelling NOTAM |
NOTAMN
|
New NOTAM |
NOTAMR
|
Replacing NOTAM |
NOV
|
November |
NOZ
|
‡ Normal operating zone |
NPA
|
Non-precision approach |
NR
|
Number |
NRH
|
No reply heard |
NS
|
Nimbostratus |
NSC
|
Nil significant cloud |
NSE
|
Navigation system error |
NSW
|
Nil significant weather |
NTL
|
National |
NTZ
|
‡ No transgression zone |
NW
|
North-west |
NWB
|
North-westbound |
NXT
|
Next |
|
O
|
|
OAC
|
Oceanic area control centre |
OAS
|
Obstacle assessment surface |
OAT
|
Operational Air Traffic* |
OBS
|
Observe or observed or observation |
OBSC
|
Obscure or obscured or obscuring |
OBST
|
Obstacle |
OCA
|
Obstacle clearance altitude |
OCA
|
Oceanic control area |
OCC
|
Occulting (light) |
OCC
|
The line is engaged* |
OCH
|
Obstacle clearance height |
OCL
|
Obstacle clearance limit* |
OCNL
|
Occasional or occasionally |
OCS
|
Obstacle clearance surface |
OCT
|
October |
OEP
|
Oceanic Entry Point |
OFZ
|
Obstacle free zone |
OGN
|
Originate (to be used in AFS as a procedure signal) |
OHD
|
Overhead |
OIS
|
Obstacle identification surface |
OK
|
We agree or it is correct (to be used in AFS as a procedure signal) |
OLDI
|
† On-line data interchange |
OM
|
Outer marker |
OPA
|
Opaque, white type of ice formation |
OPC
|
Control indicated is operational control |
OPMET
|
† Operational meteorological (information) |
OPN
|
Open or opening or opened |
OPR
|
Operator or operate or operative or operating or operational |
OPS
|
† Operations |
O/R
|
On request |
ORD
|
Order |
OSV
|
Ocean station vessel |
OTP
|
On top |
OTS
|
Organized track system |
OUBD
|
Outbound |
OVC
|
Overcast |
OXP
|
Oceanic Exit Point |
|
P
|
|
P...
|
Maximum value of wind speed or runway visual range (followed by figures in METAR/SPECI and TAF) |
P...
|
Prohibited area (followed by identification) |
PA
|
Precision approach |
PALS
|
Precision approach lighting system (specify category) |
PANS
|
Procedures for air navigation services |
PAPI
|
† Precision approach path indicator |
PAR
|
‡ Precision approach radar |
PARL
|
Parallel |
PATC...
|
Precision approach terrain chart (followed by name/title) |
PAX
|
Passenger(s) |
PBC
|
Performance-based communication |
PBN
|
Performance-based navigation |
PBS
|
Performance-based surveillance |
PCD
|
Proceed or proceeding |
PCL
|
Pilot-controlled lighting |
PCN
|
Pavement classification number |
PCT
|
Per cent |
PDC
|
‡ Pre-departure clearance |
PDG
|
Procedure design gradient |
PE
|
Ice pellets* |
PER
|
Performance |
PERM
|
Permanent |
PIB
|
Pre-flight information bulletin |
PJE
|
Parachute jumping exercise |
PL
|
Ice pellets |
PLA
|
Practice low approach |
PLVL
|
Present level |
PLN
|
Flight plan |
PN
|
Prior notice required |
PNR
|
Point to no return |
PO
|
Dust/sand whirls (Dust devils) |
POB
|
Persons on board |
POSS
|
Possible |
PPI
|
Plan position indicator |
PPR
|
Prior permission required |
PPSN
|
Present position |
PRFG
|
Aerodrome partially covered by fog |
PRI
|
Primary |
PRD
|
Prohibited – Restricted - Danger* |
PRKG
|
Parking |
PROB
|
† Probability |
PROC
|
Procedure |
PROP
|
Propeller |
PROV
|
Provisional |
PRP
|
Point-in-space reference point |
PS
|
Plus |
PSG
|
Passing |
PSGR
|
Passenger* |
PSN
|
Position |
PSP
|
Pierced steel plank |
PSR
|
‡ Primary surveillance radar |
PSYS
|
Pressure system(s) |
PTN
|
Procedure turn |
PTS
|
Polar track structure |
PUN
|
Prepare a new perforated tape for message...* |
PWR
|
Power |
|
Q
|
|
QBI
|
Compulsory IFR flight* |
QDL
|
Do 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) |
QDM
|
‡ Magnetic heading (zero wind) |
QDR
|
Magnetic bearing |
QFE
|
‡ Atmospheric pressure at aerodrome elevation (or at runway threshold) |
QFU
|
Magnetic orientation of runway |
QGE
|
What 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) |
QJH
|
Shall 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) |
QNH
|
‡ Altimeter sub-scale setting to obtain elevation when on the ground |
QSP
|
Will you relay to... free of charge? or I will relay to... free of charge (to be used in AFS as a Q Code) |
QTA
|
Shall I cancel telegram number...? or Cancel telegram number... (to be used in AFS as a Q Code) |
QTE
|
True bearing |
QTF
|
Will 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 D/F stations that I control was... latitude... longitude (or other indication of position), class... at... hours (to be used in radiotelegraphy as a Q Code) |
QUAD
|
Quadrant |
QUJ
|
Will 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
|
|
R
|
Rate of turn |
R
|
Received (acknowledgement of receipt) |
R
|
Received (acknowledgement of receipt) (to be used in AFS as a procedure signal) |
R
|
Red |
R
|
Right (preceded by runway designation number to identify a parallel runway (...R)) |
R
|
Right (preceded by runway designation number to identify a parallel runway)* |
R
|
Romeo* |
R...
|
Radial from VOR (followed by three figures) |
R...
|
Restricted area (followed by identification) |
R...
|
Runway (followed by figures in METAR/SPECI) |
RA
|
Rain |
RA
|
Resolution advisory |
RAC
|
Rules of the air and air traffic services |
RAG
|
Ragged |
RAG
|
Runway arresting gear |
RAI
|
Runway alignment indicator |
RAIM
|
Receiver autonomous integrity monitoring |
RAPID
|
Rapid or rapidly* |
RASC
|
† Regional AIS system centre |
RASH
|
Rain showers |
RASN
|
Rain and snow or showers of rain and snow* |
RASS
|
Remote altimeter setting source |
RB
|
Read back* |
RB
|
Rescue boat |
RCA
|
Reach cruising altitude |
RCC
|
Rescue co-ordination centre |
RCF
|
Radio communication failure (message type designator) |
RCH
|
Reach or reaching |
RCL
|
Runway centre line |
RCL
|
Request for Clearance. A Voice, or Data Link message via ACARS, used to provide ETA at OEP, requested Flight Level, and Mach.* |
RCLL
|
Runway centre line light(s) |
RCLR
|
Recleared |
RCP
|
‡ Required communication performance |
RDH
|
Reference datum height |
RDH
|
Reference datum height (for ILS)* |
RDL
|
Radial |
RDO
|
Radio |
RDOACT
|
Radioactive |
RE
|
Recent (used to qualify weather phenomena, e.g. recent rain = RERA) |
REC
|
Receive or receiver |
REDL
|
Runway edge light(s) |
REF
|
Reference to... or refer to... |
REG
|
Registration |
RENL
|
Runway end light(s) |
REP
|
Report or reporting or reporting point |
REQ
|
Request or requested |
RERTE
|
Re-route |
RESA
|
Runway end safety area |
RET
|
Rapid Exit Taxiway* |
RF
|
Constant radius arc to a fix |
RFFS
|
Rescue and fire fighting services |
RG
|
Range (lights) |
RHC
|
Right-hand circuit |
RIF
|
Reclearance in flight |
RIME
|
† Rime (used in aerodrome warnings) |
RITE
|
Right (direction of turn) |
RL
|
Report leaving |
RLA
|
Relay to |
RLCE
|
Request level change en route |
RLLS
|
Runway lead-in lighting system |
RLNA
|
Requested level not available |
RMK
|
Remark |
RNAV
|
† Area navigation (to be pronounced “AR-NAV”) |
RNG
|
Radio range |
RNP
|
‡ Required navigation performance |
ROBEX
|
† Regional OPMET bulletin exchange (scheme) |
ROC
|
Rate of climb |
ROD
|
Rate of descent |
ROFOR
|
Route forecast (in aeronautical meteorological code) |
RON
|
Receiving only |
ROT
|
Runway Occupancy Time* |
RPDS
|
Reference path data selector |
RPI
|
‡ Radar position indicator |
RPL
|
Repetitive flight plan |
RPLC
|
Replace or replaced |
RPS
|
Radar position symbol |
RPT
|
Repeat or I repeat |
RQ
|
Request |
RQMNTS
|
Requirements |
RQP
|
Request flight plan (message type indicator) |
RQS
|
Request supplementary flight plan (message type indicator) |
RR
|
Report reaching |
RRA
|
(or RRB, RRC... etc., in sequence) Delayed meteorological message (message type designator) |
RSC
|
Rescue sub-centre |
RSCD
|
Runway surface condition |
RSP
|
Responder beacon |
RSP
|
‡ Required surveillance performance |
RSR
|
En-route surveillance radar |
RSS
|
Root sum square |
RTD
|
Delayed (used to indicate delayed meteorological message; message type designator) |
RTE
|
Route |
RTF
|
Radiotelephone |
RTG
|
Radiotelegraph |
RTHL
|
Runway threshold light(s) |
RTN
|
Return or returned or returning |
RTODAH
|
Rejected take-off distance available, helicopter |
RTS
|
Return to service |
RTT
|
Radioteletypewriter |
RTZL
|
Runway touchdown zone light(s) |
RUT
|
Standard regional route transmitting frequencies |
RV
|
Rescue vessel |
RVA
|
Radar vectoring area |
RVR
|
‡ Runway visual range |
RVSM
|
‡ Reduced vertical separation minimum [300 m (1 000 ft) between FL 290 and FL 410] |
RWY
|
Runway |
|
S
|
|
S...
|
State of the sea (followed by figures in METAR/SPECI) |
SA
|
Sand |
SA
|
Dust-storm, sand-storm, rising dust or rising sand* |
SALS
|
Simple approach lighting system |
SAN
|
Sanitary |
SAP
|
As soon as possible* |
SAR
|
Search and rescue |
SARPS
|
Standards and Recommended Practices (ICAO) |
SAT
|
Saturday |
SATCOM
|
† Satellite communication (used only when referring generally to both voice and data satellite communication or only data satellite communication) |
SATVOICE
|
† Satellite voice communication |
SB
|
South bound |
SBAS
|
† Satellite-based augmentation system (to be pronounced “ESS-BAS”) |
SC
|
Stratocumulus |
SCT
|
Scattered |
SDBY
|
Stand by |
SDF
|
Step down fix |
SE
|
South-east |
SEA
|
Sea (used in connection with sea-surface temperature and state of the sea) |
SEB
|
South-eastbound |
SEC
|
Seconds |
SECN
|
Section |
SECT
|
Sector |
SELCAL
|
† Selective calling system |
SEP
|
September |
SER
|
Service or servicing or served |
SEV
|
Severe (used e.g. to qualify icing and turbulence reports) |
SFC
|
Surface |
SG
|
Snow grains |
SGL
|
Signal |
SH...
|
Shower (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) |
SHF
|
Super high frequency (3 000 to 30 000 MHz) |
SI
|
International system of units |
SID
|
† Standard instrument departure |
SIF
|
Selective identification feature |
SIG
|
Significant |
SIGMET
|
† Information concerning en-route weather and other phenomena in the atmosphere that may affect the safety of aircraft operations |
SIGWX
|
Significant weather* |
SIMUL
|
Simultaneous or simultaneously |
SIWL
|
Single isolated wheel load |
SKC
|
Sky clear* |
SKED
|
Schedule or scheduled |
SLOP
|
Strategic Lateral Offset Procedure* |
SLW
|
Slow |
SMC
|
Surface movement control |
SMR
|
Surface movement radar |
SN
|
Snow |
SNOWTAM
|
† A special series NOTAM given in a standard format providing a surface condition report notifying the presence or cessation of hazardous conditions due to snow, ice, slush, frost, standing water or water associated with snow, slush, ice or frost on the movement area |
SNSH
|
Snow showers* |
SOC
|
Start of climb |
SPECI
|
† Aerodrome special meteorological report (in meteorological code) |
SPECIAL
|
† Local special meteorological report (in abbreviated plain language) |
SPI
|
Special position indicator |
SPL
|
Supplementary flight plan (message type designator) |
SPOC
|
SAR point of contact |
SPOT
|
† Spot wind |
SQ
|
Squall |
SQL
|
Squall line |
SR
|
Sunrise |
SRA
|
Surveillance radar approach |
SRE
|
Surveillance radar element of precision approach radar system |
SRG
|
Short range |
SRR
|
Search and rescue region |
SRY
|
Secondary |
SS
|
Sandstorm |
SS
|
Sunset |
SSB
|
Single sideband |
SSE
|
South-south-east |
SSR
|
‡ Secondary surveillance radar |
SST
|
Supersonic transport |
SSW
|
South-south-west |
ST
|
Stratus |
STA
|
Straight-in approach |
STAR
|
† Standard instrument arrival |
STD
|
Standard |
STF
|
Stratiform |
STN
|
Station |
STNR
|
Stationary |
STOL
|
Short take-off and landing |
STS
|
Status |
STWL
|
Stopway light(s) |
SUBJ
|
Subject to |
SUN
|
Sunday |
SUP
|
Supplement (AIP supplement) |
SUPPS
|
Regional supplementary procedures |
SVC
|
Service (message type only) |
SVCBL
|
Serviceable |
SW
|
South-west |
SWB
|
South-westbound |
SWC
|
Significant Weather Chart* |
SWX
|
Space weather |
SWXC
|
Space weather centre |
SWY
|
Stopway |
|
T
|
|
T
|
Temperature |
T
|
True (preceded by a bearing to indicate reference to True North (...T)) |
TA
|
Traffic advisory |
TA
|
Transition altitude |
TA/H
|
Turn at an altitude/height |
TAA
|
Terminal Arrival Altitude |
TACAN
|
† UHF tactical air navigation aid |
TAF
|
† Aerodrome forecast (in meteorological code) |
TAIL
|
† Tail wind |
TAR
|
Terminal area surveillance radar |
TAS
|
True airspeed |
TAX
|
Taxiing or taxi |
TC
|
Tropical cyclone |
TCAC
|
Tropical cyclone advisory centre |
TCAS RA
|
† Traffic alert and collision avoidance system resolution advisory (to be pronounced “TEE-CAS-AR-AY”) |
TCH
|
Threshold Crossing Height |
TCU
|
Towering cumulus |
TDO
|
Tornado |
TDZ
|
Touchdown zone |
TECR
|
Technical reason |
TEL
|
Telephone |
TEMPO
|
† Temporary or temporarily |
TEND
|
Trend or tending to* |
TF
|
Track to fix |
TFC
|
Traffic |
TGL
|
Touch-and-go landing |
TGS
|
Taxiing guidance system |
THR
|
Threshold |
THRU
|
Through |
THU
|
Thursday |
TIBA
|
† Traffic information broadcast by aircraft |
TIL
|
† Until |
TIP...
|
Until past (followed by place) |
TIZ
|
Traffic information zone* |
TKOF
|
Take off |
TL...
|
Till (followed by time by which weather change is forecast to end) |
TLOF
|
Touchdown and lift-off area |
TMA
|
‡ Terminal control area |
TN...
|
Minimum temperature (followed by figures in TAF) |
TNA
|
Turn altitude |
TNC
|
Terminal Navigation Charge* |
TNH
|
Turn height |
TO...
|
To (followed by place) |
TOC
|
Top of climb |
TODA
|
Take-off distance available |
TODAH
|
Take-off distance available, helicopter |
TOP
|
† Cloud top |
TORA
|
Take-off run available |
TOX
|
Toxic |
TP
|
Turning point |
TR
|
Track |
TRA
|
Temporary Reserved Area |
TRANS
|
Transmits or transmitter |
TREND
|
† Trend forecast |
TRG
|
Training |
TRL
|
Transition level |
TROP
|
Tropopause |
TS
|
Thunderstorm (in aerodrome reports and forecasts, TS used alone means thunder heard but no precipitation at the aerodrome) |
TS...
|
Thunderstorm (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) |
TSA
|
Temporary Segregated Area* |
TSGR
|
Thunderstorm with hail* |
TSSA
|
Thunderstorm with duststorm or sandstorm* |
TSUNAMI
|
† Tsunami (used in aerodrome warnings) |
TT
|
Teletype-writer |
TUE
|
Tuesday |
TURB
|
Turbulence |
T-VASIS
|
† T visual approach slope indicator system (to be pronounced “TEE-VASIS”) |
TVOR
|
Terminal VOR |
TWIL
|
Twilight* |
TWR
|
Aerodrome control tower or aerodrome control |
TWY
|
Taxiway |
TWYL
|
Taxiway-link* |
TX...
|
Maximum temperature (followed by figures in TAF) |
TXL
|
Taxilane |
TXT
|
Text (when the abbreviation is used to request a repetition, the question mark (IMI) precedes the abbreviation, e.g. IMI TXT) (to be used in AFS as a procedure signal) |
TYP
|
Type of aircraft |
TYPH
|
Typhoon |
|
U
|
|
U
|
Upward (tendency in RVR during previous 10 minutes) |
UA
|
Unmanned aircraft |
UAB
|
Until advised by... |
UAC
|
Upper area control centre |
UAR
|
Upper air route |
UAS
|
Unmanned aircraft system |
UDF
|
Ultra high frequency direction-finding station |
UFN
|
Until further notice |
UHDT
|
Unable higher due traffic |
UHF
|
‡ Ultra high frequency (300 to 3000 MHz) |
UIC
|
Upper information centre |
UIR
|
‡ Upper flight information region |
ULM
|
Ultra light motorized aircraft |
ULR
|
Ultra long range |
UNA
|
Unable |
UNAP
|
Unable to approve |
UNL
|
Unlimited |
UNREL
|
Unreliable |
UP
|
Unidentified precipitation (used in automated METAR/SPECI) |
U/S
|
Unserviceable |
UTA
|
Upper control area |
UTC
|
‡ Coordinated universal time |
|
V
|
|
V
|
Variations from the mean wind direction (preceded and followed by figures in METAR/SPECI (...V...), e.g. 350V070) |
VA
|
Heading to an altitude |
VA
|
Volcanic ash |
VAAC
|
Volcanic ash advisory centre |
VAC...
|
Visual approach chart (followed by name/title) |
VAL
|
In valleys |
VAL
|
Visual approach and landing chart* |
VAN
|
Runway control van |
VAR
|
Magnetic variation |
VAR
|
Visual-aural radio range |
VASIS
|
Visual approach slope indicator system |
VC...
|
Vicinity of the aerodrome (followed by FG = fog, FC = funnel cloud, SH = shower, PO = dust/sand whirls, BLDU = blowing dust, BLSA = blowing sand, BLSN = blowing snow, DS = duststorm, SS = sandstorm, TS = thunderstorm or VA = volcanic ash, e.g. VCFG = vicinity fog) |
VCY
|
Vicinity |
VDF
|
Very high frequency direction-finding station |
VER
|
Vertical |
VFR
|
‡ Visual flight rules |
VHF
|
‡ Very high frequency (30 to 300 MHz) |
VI
|
Heading to an intercept |
VIA
|
By way of...* |
VIO
|
Heavy (used to qualify interference or static reports)* |
VIP
|
‡ Very important person |
VIS
|
Visibility |
VLF
|
Very low frequency (3 to 30 kHz) |
VLR
|
Very long range |
VM
|
Heading to a manual termination |
VMC
|
‡ Visual meteorological conditions |
VNAV
|
† Vertical navigation (to be pronounced “VEE-NAV”) |
VOL...
|
Volume (followed by I, II...) |
VOLMET
|
† Meteorological information for aircraft in flight |
VOR
|
‡ VHF omnidirectional radio range |
VORTAC
|
† VOR and TACAN combination |
VOT
|
VOR airborne equipment test facility |
VPA
|
Vertical path angle |
VPT
|
Visual manoeuvre with prescribed track |
VRB
|
Variable |
VSA
|
By visual reference to the ground |
VSP
|
Vertical speed |
VTF
|
Vector to final |
VTOL
|
Vertical take-off and landing |
VV...
|
Vertical visibility (followed by figures in METAR/SPECI and TAF) |
VVV
|
Retransmit this message to all addressees mentioned in the line-following-the-heading, as though it had been filed locally at your centre (group used in a diversion indicator)* |
VVV..VVV
|
Marking or test transmission (sent in a series)* |
|
W
|
|
W
|
West or western longitude |
W
|
White |
W...
|
Sea-surface temperature (followed by figures in METAR/SPECI) |
WA
|
Word after... * |
WAAS
|
† Wide area augmentation system |
WAC...
|
World Aeronautical Chart - ICAO 1:1 000 000 (followed by name/title) |
WAFC
|
World area forecast centre |
WAFS
|
World area forecast system* |
WB
|
Westbound |
WBAR
|
Wing bar lights |
WD
|
Words or groups* |
WDI
|
Wind direction indicator |
WDSPR
|
Widespread |
WED
|
Wednesday |
WEF
|
With effect from or effective from |
WGS-84
|
World Geodetic System — 1984 |
WHI
|
White* |
WI
|
Within |
WID
|
Width or wide |
WIE
|
With immediate effect or effective immediately |
WILCO
|
† Will comply |
WIND
|
Wind |
WIP
|
Work in progress |
WKN
|
Weaken or weakening |
WNW
|
West-north-west |
WO
|
Without |
WPT
|
Way-point |
WRNG
|
Warning |
WS
|
Wind shear |
WSPD
|
Wind speed |
WSW
|
West-south-west |
WT
|
Weight |
WTSPT
|
Waterspout |
WWW
|
Worldwide web |
WX
|
Weather |
WXR
|
Weather radar |
|
X
|
|
X
|
Cross |
XBAR
|
Crossbar (of approach lighting system) |
XNG
|
Crossing |
XS
|
Atmospherics |
XX
|
Heavy (used to qualify weather phenomena such as rain, e.g. heavy rain = XXRA)* |
|
|
Y
|
|
Y
|
Yellow |
YCZ
|
Yellow caution zone (runway lighting) |
YD
|
Yards* |
YES
|
Yes (affirmative) (to be used in AFS as a procedure signal) |
YR
|
Your |
|
|
Z
|
|
Z
|
Coordinated Universal Time (in meteorological messages) |
|