Abbreviations annotated by "+" are not included in ICAO DOC 8400.
When radiotelephony is used the abbreviations and terms annotated by "†" are transmitted as spoken words.
“*” Signal is also available for use in communicating with stations of the maritime mobile service.
“# “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 | |
A | Amber |
A/A | Air-to-air |
A/G | Air-to ground |
A2A | +Amplitude modulation, Designation of emissions |
A3E | +Amplitude modulation, Designation of emissions |
A8W | +Amplitude modulation, Designation of emissions |
A9W | +Amplitude modulation, Designation of emissions |
AAA | (Or AAB, AAC... etc. in sequence) Amended meteorological message (message type designator) |
AAD | Assigned altitude deviation |
AAIM | Aircraft autonomous integrity monitoring |
AAL | Above aerodrome level |
ABI | Advance boundary information |
ABM | Abeam |
ABN | Aerodrome beacon |
ABT | About |
ABV | Above |
AC | Altocumulus |
ACARS | †(to be pronounced „AY-CARS”) Aircraft communication addressing and reporting system |
ACAS | †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 |
ADIZ | †(to be pronounced “AY-DIZ”) Air defence identification zone |
ADJ | Adjacent |
ADO | Aerodrome office (specify service) |
ADR | Advisory route |
ADS | Automatic dependent surveillance |
ADS | *The 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) |
ADSU | Automatic dependent surveillance unit |
ADVS | Advisory service |
ADZ | Advise |
AES | Aircraft earth station |
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 ... (time or place) |
AFTN | ‡Aeronautical Fixed Telecommunication Network |
AGA | Aerodromes, air routes and ground aids |
AGL | Above ground level |
AGN | Again |
AIC | Aeronautical Information Circular |
AIDC | Air traffic services inter-facility data communication |
AIP | Aeronautical Information Publication |
AIRAC | Aeronautical Information Regulation and Control |
AIREP | †Air-report |
AIRMET | †Information concerning en-route weather phenomena which may effect the safety of low-level aircraft operations |
AIS | Aeronautical Information Services |
ALA | Alighting area |
ALERFA | †Alert phase |
ALR | Alerting (message type designator) |
ALRS | Alerting service |
ALS | Approach lighting system |
ALT | Altitude |
ALTN | Alternate or alternating (light alternates in colour) |
ALTN | Alternate (aerodrome) |
AMA | Area minimum altitude |
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 |
AOC | Aerodrome obstacle chart (followed by name /title) |
AOR | +Area of responsibility |
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 ... |
APV | Approve or approved or approval |
ARC | Area chart |
ARNG | Arrange |
ARO | Air traffic services reporting office |
ARP | Aerodrome reference point |
ARP | Air-report (message type designator) |
ARQ | Automatic error correction |
ARR | Arrive |
ARR | Arrival (message type designator) |
ARS | Special air-report (message type designator) |
ARST | Arresting (specify /part of/ aircraft arresting equipment) |
AS | Altostratus |
ASC | Ascent to or ascending to |
ASDA | Accelerate stop distance available |
ASE | Altimetry system error |
ASMGCS | Advanced Surface Movement Guidance and Control System |
ASPEEDL | Airspeed loss |
ASPH | Asphalt |
AT | At (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 |
ATA | ‡Actual time of arrival |
ATC | ‡Air Traffic Control (in general) |
ATD | ‡Actual time of departure |
ATFM | Air traffic flow management |
ATFMP | +Air traffic flow management position |
ATFMU | +Air traffic flow management unit |
ATIS | †Automatic terminal information service |
ATM | Air traffic management |
ATN | Aeronautical telecommunication network |
ATP | At.. (time or place) |
ATS | Air traffic services |
ATTN | Attention |
ATZ | Aerodrome traffic zone |
AUG | August |
AUTH | Authorized or authorization |
AUW | All up weight |
AUX | Auxiliary |
AVBL | Available or availability |
AVG | Average |
AVGAS | †Aviation gasoline |
AWTA | Advise at what time able |
AWY | Airway |
AZM | Azimuth |
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 | |
B | Blue |
B-RNAV | +Basic area navigation |
BA | Braking action |
BASE | †Cloud base |
BCFG | Fog patches |
BCN | Beacon (aeronautical ground light) |
BCST | Broadcast |
BDRY | Boundary |
BECMG | Becoming |
BFR | Before |
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 |
BRG | Bearing |
BRKG | Braking |
BS | Commercial broadcasting station |
BTL | Between layers |
BTN | Between |
BUFR | Binary universal form for the representation of meteorological data |
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 | |
C | Centre (runway identification) |
C | Degrees Celsius (centigrade) |
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 | ‡(to be pronounced “CEE-BEE”) Cumulonimbus |
CC | Cirrocumulus |
CCA | (or CCB, CCC... etc., in sequence) Corrected meteorological message (message type designator) |
CD | Candela |
CDN | Coordination message |
CDR | +Conditional Route |
CF | Change frequency to... |
CFM | *Confirm or I confirm (to be used in AFS as a procedure signal) |
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 |
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 or cleared to ... or clearance |
CLRD | Runway(s) cleared (used in METAR/SPECI) |
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 |
COM | Communications |
CONC | Concrete |
COND | Condition |
CONS | Continuous |
CONST | Construction or constructed |
CONT | Continue(s) or continued |
COOR | Coordinate, or coordination |
COORD | Coordinates |
COP | Change-over point |
COR | Correct or corrected or correction |
COT | At the coast |
COV | Cover or covered or covering |
CPDLC | ‡Controller – pilot data link communications |
CPL | Current flight plan message |
CRC | Cyclic redundancy check |
CRM | +Collision risk model |
CRZ | Cruise |
CS | Cirrostratus |
CS | Call sign |
CTA | Control area |
CTAM | Climb to and maintain |
CTC | Contact |
CTL | Control |
CTN | Caution |
CTOT | +Calculated take-off time |
CTR | Control zone |
CU | Cumulus |
CUF | Cumuli form |
CUST | Customs |
CVR | Cockpit voice recorder |
CW | Continuous wave |
CWY | Clearway |
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 | |
D | Downward (tendency in RVR during previous 10 minutes) |
D | Danger area (followed by identification) |
D - ATIS | †(to be pronounced “DEE – ATIS”) Data link automatic terminal information service |
DA | Decision altitude |
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 |
DEP | Depart or departure or departure message |
DEPO | Deposition |
DES | Descend to or descending to |
DEST | Destination |
DETRESFA | †Distress phase |
DEV | Deviation or deviating |
DF | +Direction finder or finding |
DFDR | Digital flight data recorder |
DFTI | Distance from touch down indicator |
DGCA | +Director General of Civil Aviation |
DH | Decision height |
DIF | Diffuse |
DIST | Distance |
DIV | Divert or diverting |
DLA | Delay or delayed |
DLA | Delay (message type designator) |
DLIC | Data link initiation capability |
DLY | Daily |
DME | ‡Distance measuring equipment |
DNG | Danger or dangerous |
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 | Dust storm |
DSB | Double sideband |
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 |
DVOR | Doppler VOR |
DW | Dual wheels |
DZ | Drizzle |
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 | |
D–VOLMET | Data link VOLMET |
E | East or Eastern longitude |
EAT | Expected approach time |
EB | Eastbound |
EDA | Elevation differential area |
EEE | #Error (to be used in AFS as a procedure signal) |
EET | Estimated elapsed time |
EFC | Expect further clearance |
EGNOS | †European geostationary navigation overlay service |
EHF | Extremely high frequency (30000 to 300000 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 |
EN | +English |
END | Stop-end (related to RVR) |
ENE | East-north-east |
ENG | Engine |
ENR | En route |
ENRC | Enroute chart (followed by name/title) |
EOBT | Estimated off-block time |
EQPT | Equipment |
ER | *Here...or herewith |
ESE | East-south-east |
EST | Estimate or estimated or estimate (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 |
EVS | Enhanced vision system |
EXC | Except |
EXER | Exercise or exercising or to exercise |
EXP | Expected or expending |
EXTD | Extended or extending |
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 | |
F | Fixed |
FAC | Facilities |
FAF | Final approach fix |
FAL | Facilitation of international air transport |
FAP | Final approach point |
FATO | Final approach and take-off area |
FAWP | +Final approach way point |
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 (tornado or water spout) |
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 | From |
FM | From (followed by time weather charge is forecast to begin) |
FMS | ‡Flight management system |
FMU | Flow management unit |
FNA | Final approach |
FPAP | Flight pass alignment point |
FPL | Filed flight plan (message type designator) |
FPM | Feet per minute |
FPR | Flight plan route |
FR | Fuel remaining |
FRA | +Free Route Airspace |
FREQ | Frequency |
FRI | Friday |
FRNG | Firing |
FRONT | †Front (relating to weather) |
FRQ | Frequent |
FSL | Full stop landing |
FSS | Flight service station |
FST | First |
FT | Feet (dimensional unit) |
FTP | Fictitious threshold point |
FU | Smoke |
FUA | +Flexible use of airspace |
FZ | Freezing |
FZDZ | Freezing drizzle |
FZFG | Freezing fog |
FZRA | Freezing 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 | |
G | Green |
G | Variations from the mean wind speed (gust) (followed by figures in the METAR/SPECI and TAF |
G/A | Ground to air |
G/A/G | Ground to air and air to ground |
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 head wing gain |
GAMET | Area forecast for low-level flights |
GARP | GBAS azimuth referential point |
GAT | +General air traffic |
GBAS | †Ground-based augmentation system (to be pronounced “GEE-BAS”) |
GCA | ‡Ground control approach system or ground control approach |
GDCA | +General Directorate of Civil Aviation |
GEN | General |
GEO | Geographic or true |
GES | Ground earth station |
GLD | Glider |
GLONASS | †(to be pronounced “GLO-NAS”) Global orbiting navigation satellite system |
GLS | ‡GBAS landing system |
GMC | Ground movement chart (followed by name/title) |
GND | Ground |
GNDCK | Ground check |
GNSS | ‡Global navigation satellite system |
GP | Glide path |
GPS | ‡Global positioning system |
GR | Hail |
GRAS | †Ground-based regional augmentation system (to be pronounced “GRASS”) |
GRASS | Grass landing area |
GRIB | Processed meteorological data in the form of grid point values (in aeronautical meteorological code) |
GRVL | Gravel |
GS | Ground speed |
GS | Small hail and/or snow pellets |
GUND | Geoid 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 | |
H | High pressure area or the centre of high pressure |
H24 | Continuous day and night service |
HAPI | Helicopter approach path indicator |
HBN | Hazard beacon |
HDF | High frequency direction finding station |
HDG | Heading |
HEL | Helicopter |
HF | ‡High frequency (3000 to 30000 kHz) |
HGT | Height or height above |
HIAL | +High intensity approach lights |
HIRL | +High intensity runway lights |
HJ | Sunrise to sunset |
HLDG | Holding |
HN | Sunset to sunrise |
HNG | +Hungarian or Hungary |
HO | Service available to meet operational requirements |
HOL | Holiday |
HOSP | Hospital aircraft |
HPA | Hectopascal |
HR | Hours |
HS | Service available during hours of scheduled operations |
HUD | Head-up display |
HUF | +Hungarian forints |
HUFRA | +Hungarian Free Route Airspace |
HURCN | Hurricane |
HVDF | High and very high frequency direction finding stations (at the same position) |
HVY | Heavy |
HVY | Heavy (used to indicate the intensity of weather phenomena (e.g. HVY RA = heavy rain) |
HWS | +Horizontal wind shear |
HX | No specific working hours |
HYR | Higher |
HZ | Haze |
HZ | Hertz (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 | |
IAC | Instrument approach chart (followed by name/title) |
IAF | Initial approach fix |
IAP | Instrument approach procedure |
IAR | Intersection of air routes |
IAS | Indicated air speed |
IBN | Identification beacon |
IC | Ice crystals (very small ice crystals in suspension also known as diamond dust) |
ICAO | +International Civil Aviation Organization |
ICE | Icing |
ID | Identifier or identify |
IDENT | †Identification |
IF | Intermediate approach fix |
IFF | Identification friend/foe |
IFPS | +Integrated initial flight plan processing system |
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 |
INFO | †Information |
INOP | Inoperative |
INP | If not possible |
INPR | In progress |
INS | Inertial navigation system |
INS | +Inches |
INSTL | Install or installed or installation |
INSTR | Instrument |
INT | Intersection |
INTL | International |
INTRG | Interrogator |
INTRP | Interrupt or interruption or interrupted |
INTSF | Intensify or intensifying |
INTST | Intensity |
IR | Ice on runway |
ISA | International standard atmosphere |
ISB | Independent sideband |
ISOL | Isolated |
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 | |
JAA | +Joint Aviation Authorities |
JAN | January |
JTST | Jet stream |
JUL | July |
JUN | June |
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 | |
KG | Kilogrammes |
KHZ | Kilohertz |
KIAS | +Knots indicated airspeed |
KM | Kilometres |
KMH | Kilometres/hour |
KPA | Kilo pascal |
KT | Knots |
KW | Kilowatts |
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 | |
L | Left (preceded by runway designator number too identify a parallel runway) |
L | Locator (see LM, LO) |
LAM | Logical acknowledgement (message type designator) |
LAN | Inland |
LAT | Latitude |
LDA | Landing distance available |
LDAH | Landing distance available, helicopter |
LDG | Landing |
LDI | Landing direction indicator |
LEN | Length |
LF | Low frequency (30 to 300 kHz) |
LGT | Light or lighting |
LGTD | Lighted |
LI | +Locator inner |
LIH | Light intensity high |
LIL | Light intensity low |
LIM | Light intensity medium |
LLZ | Localizer |
LM | Locator, middle |
LMT | Local Mean Time |
LNG | Long (used to indicate the type of approach desired or required) |
LO | Locator outer |
LOC | Locally or location or located |
LONG | Longitude |
LORAN | †LORAN (long range air navigation system) |
LOSS | Airspeed or headwind loss |
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 ….(to be used in AFS as a procedure signal) |
LT | +Local Time |
LTD | Limited |
LTF | +Land line telephone |
LTP | Landing threshold point |
LTT | Land line teletypewriter |
LV | Light and variable (relating to wind) |
LVE | Leave or leaving |
LVL | Level |
LYR | Layer 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 | |
M | Mach number (followed by figures) |
M | Metres (preceded by figures) |
M | Minimum values of runway visual range (followed by figures in the METAR/SPECI and TAF) |
MAA | Maximum authorized altitude |
MAG | Magnetic |
MAINT | Maintenance |
MAP | Aeronautical maps and charts |
MAPT | Missed approach point |
MAR | March |
MAR | At sea |
MAS | Manual A1 simplex |
MAX | Maximum |
MAY | May |
MBST | Microburst |
MCA | Minimum crossing altitude |
MCTR | +Military CTR |
MCW | Modulated continuous wave |
MDA | Minimum descent altitude |
MDF | Medium frequency direction-finding station |
MDH | Minimum descent height |
MEA | Minimum en-route altitude |
MEHT | Minimum eye-height over threshold (for visual approach slope indicator systems) |
MET | †Meteorological or meteorology |
METAR | †Aviation routine weather report (in aeronautical meteorological code) |
METREPORT | Local routine meteorological report (in abbreviated plain language) |
MF | Medium frequency (300 to 3000 kHz) |
MHDF | Medium and high frequency direction- finding stations (at the same position) |
MHVDF | Medium, high and very high frequency direction-finding stations (at the same position) |
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 |
MLS | ‡Microwave landing system |
MM | Middle marker |
MMO | +Main Meteorological Office |
MNM | Minimum |
MNPS | Minimum navigation performance specifications |
MNT | Monitor or monitoring or monitored |
MNTN | Maintain |
MOA | Military operating area |
MOC | Minimum obstacle clearance (required) |
MOD | Moderate (used to indicate the intensity of weather phenomena, interference or static reports e.g. MOD RA = moderate rain) |
MON | Above mountains |
MON | Monday |
MOPS | †Minimum operational performance standards |
MOV | Move or moving or movement |
MPS | Metres per second |
MRA | Minimum reception altitude |
MRG | Medium range |
MRP | ATS per MET reporting point |
MS | Minus |
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 |
MSL | Mean sea level |
MSR | #Message … (transmission identification) has been misrouted (to be used in AFS as a procedure signal) |
MSSR | Mono pulse secondary surveillance radar |
MT | Mountain |
MTOW | +Maximum take-off weight |
MTU | Metric units |
MTW | Mountain waves |
MVDF | Medium and very high frequency direction-finding stations (at the same position) |
MWO | Meteorological watch office |
MX | Mixed 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 | |
N | North or Northern latitude |
N | No distinct tendency (in RVR during previous 10 minutes) |
NASC | †National AIS system centre |
NAT | North Atlantic |
NAV | Navigation |
NB | Northbound |
NBFR | Not before |
NC | No change |
NCD | No cloud detected (used in automated METAR/SPECI) |
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 |
NGT | Night |
NIL | *†None or I have nothing to send to you |
NM | Nautical miles |
NML | Normal |
NN | No name, unnamed |
NNE | North - north-east |
NNW | North - north-west |
NO | No (negative) (to be used in AFS as a procedure signal) |
NOF | International NOTAM office |
NON | +Designation of non-modulated |
NONFUA | +Not subject to Flexible use of airspace |
NOSIG | †No significant change (used in trend type landing forecasts) |
NOTAM | †A 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. |
NOV | November |
NOZ | ‡Normal operating zone |
NR | Number |
NRH | No reply heard |
NS | Nimbostratus |
NSC | Nil significant cloud |
NSW | Nil significant weather |
NTL | National |
NTZ | ‡No transgression zone |
NW | North-west |
NWB | North-westbound |
NXT | Next |
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/R | On request |
OAC | Oceanic area control centre |
OAS | Obstacle assessment surface |
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) |
OCH | Obstacle clearance height |
OCNL | Occasional or occasionally |
OCS | Obstacle clearance surface |
OCT | October |
OFZ | Obstacle free zone |
OGN | Originate (to be used in AFS as a procedure signal) |
OHD | Overhead |
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 |
ORD | Indication of an order |
OSV | Ocean station vessel |
OTP | On top |
OTS | Organized track system |
OUBD | Outbound |
OVC | Overcast |
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 | |
P | Maximum values of runway visual range (followed by figures in the METAR/SPECI and TAF) |
P | Prohibited area (followed by identifier) |
P2 | +Prognostic chart for 200 hPa |
P3 | +Prognostic chart for 300 hPa |
P5 | +Prognostic chart for 500 hPa |
P7 | +Prognostic chart for 700 hPa |
P85 | +Prognostic chart for 850 hPa |
PA | Precision approach |
PALS | Precision approach lighting system |
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) |
PBN | Performance-based navigation |
PCD | Proceed or proceeding |
PCL | Pilot controlled lighting |
PCN | Pavement classification number |
PDC | ‡Pre – departure clearance |
PDG | Procedure design gradient |
PER | Performance |
PERM | Permanent |
PIB | Pre-flight information bulletin |
PJE | Parachute jumping exercise |
PL | Ice pellets |
PLA | Practice low approach |
PLN | Flight plan |
PLVL | Present level |
PN | Prior notice required |
PNR | Point of no return |
PO | Dust/sand whirls (dust devils) |
POB | Persons on board |
PON | +Pulse modulation, designation of emissions |
POSS | Possible |
PPI | Plan position indicator |
PPR | Prior permission required |
PPSN | Present position |
PRFG | Aerodrome partially covered by fog |
PRI | Primary |
PRKG | Parking |
PROB | †Probability |
PROC | Procedure |
PROV | Provisional |
PS | Plus |
PSG | Passing |
PSN | Position |
PSP | Pierced steel plank |
PSR | ‡Primary surveillance radar |
Psw | +Prognostic chart of significant weather |
PSYS | Pressure system(s) |
PTN | Procedure turn |
PTrVM | +Prognostic tropopause and maximum wind chart |
PTS | Polar track structure |
PWR | Power |
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 | |
QDL | Do you intend to to ask me for a series of bearings? or I intend to ask 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 … |
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 - 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 | |
R | Right (preceded by runway designator number to identify a parallel runway) |
R | Red |
R | Runway visual range (followed by figures in the METAR/SPECI) |
R | *Received (acknowledgement of receipt) (to be used in AFS as a procedure signal) |
R | Restricted area (followed by identification) |
R | +Radial (VOR) |
RA | Rain |
RAC | Rules of the air and air traffic services |
RAG | Ragged |
RAI | Runway alignment indicator |
RAIM | †Receiver autonomous integrity monitoring |
RASC | †Regional AIS system centre |
RASS | Remote altimeter setting source |
RB | Rescue boat |
RCA | Reach cruising altitude |
RCC | Rescue coordination centre |
RCF | Radio communication failure message |
RCH | Reach or reaching |
RCL | Runway centre line |
RCLL | Runway centre line light(s) |
RCLR | Re cleared |
RDH | Reference datum height |
RDL | Radial |
RDO | Radio |
RE | Recent (used to qualify weather phenomena e.g. RE RA = recent rain) |
REA | +Ready message |
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 | Reroute |
RESA | RWY end safety area |
RFC | +Radio facility chart |
RG | Range (lights) |
RHC | Right-hand circuit |
RIF | Re clearance on flight |
RITE | Right (direction of turn) |
RL | Report leaving |
RLA | Relay to |
RLCE | Request level change enroute |
RLLS | Runway lead-in lighting system |
RLNA | Request level not available |
RMAC | Radar minimum altitude chart |
RMK | Remark |
RNAV | †(to be pronounced "AR-NAV") Area navigation |
RNG | Radio range |
RNP | Required navigation performance |
ROBEX | †Regional OPMET bulletin exchange (scheme) |
ROC | Rate of climb |
ROD | Rate of descent |
RON | Receiving only |
RPI | ‡Radar position indicator |
RPL | Repetitive flight plan |
RPLC | Replace or replaced |
RPS | Radar position symbol |
RPT | *Repeat or I repeat (to be used in AFS as a procedure signal) |
RQ | *Request (to be used in AFS as a procedure signal) |
RQMNTS | Requirements |
RQP | Request flight plan (message type designator) |
RQS | Request supplementary flight plan (message type designator) |
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 |
RSR | En-route surveillance radar |
RTD | Delayed (used to indicate delayed meteorological message; message type designator) |
RTE | Route |
RTF | Radio telephone |
RTG | Radio telegraph |
RTHL | Runway threshold light(s) |
RTN | Return or returned or returning |
RTODAH | Rejected take-off distance available helicopter |
RTS | Return to service |
RTT | Radio teletypewriter |
RTZL | Runway touchdown zone light(s) |
RUT | Standard regional route transmitting frequencies |
RV | Rescue vessel |
RVR | ‡Runway visual range |
RVSM | ‡Reduced Vertical Separation Minima (300 m/1000 ft between FL 290 and FL 410) |
RWY | Runway |
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 | |
S | State of the sea (followed by figures in METAR/SPECI) |
S | South or Southern latitude |
S6 | +6-hourly surface synoptic chart |
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 | |
SA | 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 |
SB | Southbound |
SBAS | †Satellite-based augmentation system (to be pronounced “SS-BASS”) |
SC | Stratocumulus |
SCT | Scattered |
SDBY | Stand by |
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 | Showers (followed by RA = rain, SN = snow, PE = 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 (3000 to 30000 Mhz) |
SID | †Standard instrument departure |
SIF | Selective identification feature |
SIG | Significant |
SIGMET | †Information concerning en-route weather phenomena which may effect the safety of aircraft operations |
SIMUL | Simultaneous or simultaneously |
SIWL | Single isolated wheel load |
SKED | Schedule or scheduled |
SLAP | +Slot allocation procedure |
SLP | Speed limiting point |
SLT | +Slot allocation message |
SLW | Slow |
SMC | Surface movement control |
SMR | Surface movement radar |
SN | Snow |
SNOCLO | Aerodrome closed due to snow (used in METAR/SPECI) |
SNOWTAM | †A 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 pro format. |
SOC | +Start of climb |
SPECI | †Aviation selected special weather report (in aeronautical meteorological code) |
SPECIAL | †Special meteorological report (in abbreviated plain language) |
SPL | Supplementary flight plan message |
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 |
SRQ | +Slot request message |
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 | Strati form |
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 |
SVCBL | Serviceable |
SW | South-west |
SWB | South-westbound |
SWY | Stopway |
T | Temperature |
T | True (preceded by a bearing to indicate reference to True North) |
T-VASIS | †(to be pronounced “TEE –VASIS”) T visual approach slope indicator system |
TA | Transition altitude |
TAA | Terminal arrival altitude |
TACAN | UHF tactical air navigation aid |
TAF | †Aerodrome forecast |
TAIL | †Tail wind |
TAR | Terminal area surveillance radar |
TAS | True airspeed |
TAX | Taxiing or taxi |
TC | Tropical cyclone |
TCA | +Area of responsibility of TMA sector |
TCP | +Transfer of control point |
TCU | Towering cumulus |
TDA | +Area or responsibility of BUDAPEST DIRECTOR |
TDO | Tornado |
TDZ | Touchdown zone |
TECR | Technical reason |
TEL | Telephone |
TEMPO | †Temporary or temporarily |
TEND | †Trend forecast |
TFC | Traffic |
TGL | Touch-and-go landing |
TGL | +Temporary Guidance Leaflet |
TGS | Taxiing guidance system |
THR | Threshold |
THRU | Through |
THU | Thursday |
TIBA | †Traffic information broadcast by aircraft |
TIL | †Until |
TIP | Until past... (place) |
TIZ | +Traffic Information Zone |
TKOF | Take-off |
TL | Till (followed by time which weather change is forecast of end) |
TLOF | Touchdown and lift-off area |
TMA | Terminal control area |
TN | Minimum temperature (followed by figures in TAF) |
TNA | Turn altitude |
TNH | Turn Height |
TO | To... (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 airspace |
TRANS | Transmits or transmitter |
TRCC | +Terminal Radar Control Centre |
TREND | Trend forecast |
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, PE=ice pellets, GA=hail, GS=small hail and/or snow pellets or combinations thereof, e.g. TSRASN=thunderstorm with rain and snow) |
TSA | +Temporary Segregated Area |
TT | Teletypewriter |
TUE | Tuesday |
TURB | Turbulence |
TVOR | Terminal VOR |
TWR | Aerodrome control tower or aerodrome control |
TWY | Taxiway |
TWYL | Taxiway-link |
TX | Maximum temperature (followed by figures in TAF) |
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 - 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 | |
U | Upward (tendency in RVR during previous 10 minutes) |
U/S | Unserviceable |
U2 | +200 hPa chart |
U25 | +250 hPa chart |
U3 | +300 hPa chart |
U4 | +400 hPa chart |
U5 | +500 hPa chart |
U7 | +700 hPa chart |
U85 | +850 hPa chart |
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 | |
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 |
ULR | Ultra long range |
UNA | Unable |
UNAP | Unable to approve |
UNL | Unlimited |
UNREL | Unreliable |
UP | Unidentified precipitation (used in automated METAR/SPECI) |
USD | +US dollar |
UTA | ‡Upper control area |
UTC | Coordinated universal time |
V | Variations from the mean wind direction (preceded and followed by figures in the METAR/SPECI, e.g. 350V070) |
VA | Volcanic ash |
VAC | Visual approach chart (followed by name/title) |
VAL | In valleys |
VAN | Runway control van |
VAR | Magnetic variation |
VAR | Visual-aural radio range |
VASIS | Visual approach slope indicator systems |
VC | Vicinity of the aerodrome (followed by FG=fog, FC=funnel cloud, PO=dust/sand whirls, BLDU=blowing dust, BLSA=blowing sand or BLSN=blowing snow, e.g. VC FG=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) |
VIP | ‡Very important person |
VIS | Visibility |
VLF | Very low frequency 3 to 30 kHz) |
VLR | Very long range |
VMC | ‡Visual meteorological conditions |
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 pass angle |
VPT | Visual manoeuvre with prescribed track |
VRB | Variable |
VSA | By visual reference to the ground |
VSP | Vertical speed |
VTOL | Vertical take-off and landing |
VV | Vertical visibility (followed by figures in METAR/SPECI and TAF) |
VWS | +Vertical wind shear |
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 | |
W | Sea-surface temperature (followed by figures in METAR/SPECI) |
W | West or western longitude |
W | White |
WAAS | †Wide area augmentation system |
WAC | World Aeronautical Chart – ICAO 1 : 1 000 000 (followed by name/title) |
WAFC | World Area Forecast Centre |
WB | Westbound |
WBAR | Wing bar lights |
WD | +Working day |
WDI | Wind direction indicator |
WDSPR | Widespread |
WE | +Weekend |
WED | Wednesday |
WEF | With effect from or effective from |
WGS-84 | World geodetic system- 1984 |
WI | Within |
WID | Width |
WIE | With immediate effect or effective immediately |
WILCO | †Will comply |
WIND | Wind |
WIP | Work in progress |
WKN | Weaken or weakening |
WMO | +World Meteorological Organization |
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 | World wide web |
WX | Weather |
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 | |
X | Cross |
XBAR | Crossbar (of approach lighting system) |
XNG | Crossing |
XS | Atmospherics |
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 | |
Y | Yellow |
YCZ | Yellow caution zone (runway lighting) |
YES | *Yes (affirmative) (to be used in AFS as a procedure signal) |
YR | Your |
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 | |
Z | Coordinated Universal Time (in meteorological messages) |