Abbreviations and acronyms
This list covers general and meteorological abbreviations and acronyms which may be found throughout the Guide and on associated charts, or which are used in NOTAM, AIP Supplements and meteorological messages and documentation.
NOTE
* Abbreviation may be used as spoken words in radio telephony.
† Abbreviation may be spoken using the constituent letters rather than the phonetic alphabet.
A
|
A/A
|
Air to Air |
|
A/G
|
Air-to-ground |
|
AACC
|
Area Approach Control Centre |
|
AAD
|
Assigned altitude deviation |
|
AAIS
|
Automatic Aerodrome Information Service |
|
AAL
|
Above aerodrome level |
|
ABI
|
Advance boundary information |
|
ABM
|
Abeam |
|
ABN
|
Aerodrome beacon |
|
ABT
|
About |
|
ABV
|
Above |
|
AC
|
Altocumulus |
|
ACARS*
|
Aircraft communication aAddressing and reporting system (pronounced ‘ay-cars’) |
|
ACAS*
|
Airborne Collision Avoidance System |
|
ACCID
|
Initial notification of an aircraft accident |
|
ACC†
|
Area control centre |
|
ACD
|
Airways clearance delivery |
|
ACFT
|
Aircraft |
|
ACK
|
Acknowledge |
|
ACN
|
Aircraft classification number |
|
ACPT
|
Accept, accepted |
|
ACT
|
Active, activated, activity |
|
AD
|
Aerodrome |
|
ADC
|
Aerodrome chart |
|
ADDGM
|
Aerodrome diagrams |
|
ADDN
|
Addition, additional |
|
ADF†
|
Automatic direction finding equipment |
|
ADIZ†
|
Air defence identification zone |
|
ADJ
|
Adjacent |
|
ADMS
|
Aeronautical database management system |
|
ADR
|
Advisory route |
|
ADS-B†
|
Automatic dependent surveillance-broadcast |
|
ADS-C†
|
Automatic dependent surveillance-contract |
|
ADZ
|
Advise |
|
AEP
|
Aerodrome emergency plan |
|
AERIS*
|
Automatic En Route Information Service |
|
AFIL
|
Flight notification (filed in the air, or indicating the position at which ATS services will first be required) |
|
AFM
|
Yes, affirm, affirmative, that is correct |
|
AFRU
|
Aerodrome frequency response unit |
|
AFS
|
Aeronautical fixed service |
|
AFT
|
After |
|
AFTN†
|
Aeronautical fixed telecommunication network |
|
AFZ
|
Australian fishing zone(s) |
|
AGA
|
Aerodromes, air routes and ground aids |
|
AGL†
|
Above ground level |
|
AGN
|
Again |
|
AH
|
After hours |
|
AIC†
|
Aeronautical information circular |
|
AIP†
|
Aeronautical Information Publication |
|
AIRAC*
|
Aeronautical Information Regulation and Control |
|
AIREP*
|
Air report |
|
AIRMET*
|
Information in plain language concerning weather significant to light aircraft operations at or below 10,000 ft |
|
AIS†
|
Aeronautical Information Service |
|
AL
|
Approach lights |
|
ALA†
|
Aircraft landing area (for the purpose of CAR 92(1)(d)) |
|
ALERFA*
|
Alert phase |
|
ALM
|
Aircraft landing minima |
|
ALR
|
Alerting message |
|
ALS
|
Approach lighting system |
|
ALT
|
Altitude |
|
ALTN
|
Alternate, alternating (light alternates in colour) |
|
ALTN
|
Alternate (aerodrome) |
|
AMD
|
Amend, amended |
|
AMDT
|
Amendment (AIP Amendment) |
|
AMSL†
|
Above mean sea level |
|
ANC
|
Aeronautial chart 1:500,00 (followed by name/title) |
|
AOC
|
Aerodrome obstruction chart (followed by name/title) |
|
AOC
|
Air operator’s certificate |
|
AP
|
Airport |
|
APAPI*
|
Abbreviated precision approach path indicator (pronounced ‘ay-papi’) |
|
APCH
|
Approach |
|
APDC
|
Aircraft parking/docking chart (followed by name/title) |
|
APN
|
Apron |
|
APP
|
Approach control, approach control office, approach control service |
|
APR
|
April |
|
APRX
|
Approximate, approximately |
|
APSG
|
After passing |
|
APV
|
Approve, approved, approval |
|
AQZ
|
Area QNH Zone |
|
ARFL
|
Aeroplane reference field length |
|
ARN
|
Aviation reference number |
|
ARNG
|
Arrange |
|
ARP
|
Aerodrome reference point |
|
ARP
|
Air report (message type designator) |
|
ARR
|
Arrive, arrival |
|
ARS
|
Special air report (message type designator) |
|
AS
|
Altostratus |
|
ASAP†
|
As soon as possible |
|
ASC
|
Ascent to, ascending to |
|
ASDA
|
Accelerate-stop distance available |
|
ASE
|
Altmetry system error |
|
A-SMGCS
|
Advanced surface movement guidance and control system |
|
ASPH
|
Asphalt |
|
ASR
|
Area surveillance radar |
|
ATA†
|
Actual time of arrival |
|
ATC†
|
Air traffic control (in general) |
|
ATD†
|
Actual time of departure |
|
ATFM
|
Air traffic flow management |
|
ATIS*
|
Automatic terminal information service |
|
ATM
|
Air traffic management |
|
ATP
|
At (Time or Place) |
|
ATS
|
Air traffic services |
|
ATTN
|
Attention |
|
AT-VASIS*
|
Abbreviated ‘T’ visual approach slope indicator system (pronounced ‘ay-tee-vasis’) |
|
ATZ
|
Aerodrome traffic zone |
|
AUG
|
August |
|
AUTH
|
Authorised, authorisation |
|
AUTO
|
Fully automated report (met code) |
|
AUW
|
All-up weight |
|
AUX
|
Auxiliary |
|
AVBL
|
Available |
|
AVG
|
Average |
|
AVGAS*
|
Aviation gasoline |
|
AVM
|
Abrupt vertical manoeuvres (by the military) |
|
AWIS
|
Aerodrome Weather Information Service |
|
AWK
|
Aerial work |
|
AWS
|
Automatic weather station |
|
AWY
|
Airway |
|
AZM
|
Azimuth |
B
|
B
|
Blue |
|
BASE*
|
Cloud base |
|
BCFG
|
Fog patches |
|
BCN
|
Beacon (aeronautical ground light) |
|
BCST
|
Broadcast |
|
BCTA
|
Base of CTA (only on charts) |
|
BDRY
|
Boundary |
|
BECMG
|
Becoming |
|
BFR
|
Before |
|
BKN
|
Broken (cloud descriptor) |
|
BL
|
Blowing (followed by: DU = dust; SA = sand; SN = snow) |
|
BLDG
|
Building |
|
BLO
|
Below clouds |
|
BLW
|
Below |
|
BOMB
|
Bombing |
|
BR
|
Mist |
|
BRF
|
Brief/short (to indicate type of approach) |
|
BRG
|
Bearing |
|
BRKG
|
Braking |
|
BS
|
Broadcasting station (commercial) |
|
BTL
|
Between layers |
|
BTN
|
Between |
C
|
C
|
Centre (runway) |
|
C/L
|
Centre line |
|
CA/GRS
|
Certified air / ground radio service |
|
CAO
|
Civil Aviation Order |
|
CAR
|
Civil Aviation Regulation |
|
CASA
|
Civil Aviation Safety Authority |
|
CAT
|
Clear air turbulence |
|
CAT*
|
Category |
|
CAVOK*
|
Visibility, cloud and present weather better than prescribed values of conditions (pronounced ‘cav-okay’) |
|
CB†
|
Cumulonimbus |
|
CC
|
Cirrocumulus |
|
CCTS
|
Circuits |
|
CEN
|
En route and area ATC unit |
|
CET
|
Clearance expiry time |
|
CF
|
Change frequency to |
|
CFM
|
Confirm, I confirm |
|
CH
|
Channel |
|
CHTR
|
Charter |
|
CI
|
Cirrus |
|
CIT
|
Near, over large town(s) |
|
CIV
|
Civil |
|
CK
|
Check |
|
CLA
|
Clear type of ice formation |
|
CLBR
|
Calibration |
|
CLD
|
Cloud |
|
CLG
|
Calling |
|
CLIAS
|
Climbing indicated airspeed |
|
CLR
|
Clear, cleared to, clearance |
|
CLSD
|
Closed, close, closing |
|
CM
|
Centimetre |
|
CMB
|
Climb to, climbing to |
|
CMPL
|
Completion, completed, complete |
|
CMSD
|
Commissioned |
|
CNL
|
Cancel, cancellation |
|
CNL
|
Flight plan cancellation message |
|
CNS
|
Communications, navigation and surveillance |
|
COM
|
Communications |
|
CONC
|
Concrete |
|
COND
|
Condition |
|
CONS
|
Continuous |
|
CONST
|
Construction, constructed |
|
CONT
|
Continue(s), continued |
|
COOR
|
Coordinate, coordinated |
|
COORD
|
Coordinates |
|
COP
|
Change-over point |
|
COR
|
Correct, corrected, correction |
|
COS
|
Conical surface |
|
COT
|
At the coast, coastal |
|
COV
|
Cover, covered, covering |
|
CPDLC†
|
Controller pilot datalink communication |
|
CRC
|
Cyclic redundancy check |
|
CRZ
|
Cruise |
|
CS
|
Cirrostratus |
|
CS
|
Call sign |
|
CTAF*
|
Common traffic advisory frequency |
|
CTA†
|
Control area |
|
CTC
|
Contact |
|
CTL
|
Control |
|
CTN
|
Caution |
|
CTR
|
Control zone |
|
CU
|
Cumulus |
|
CUF
|
Cumuliform |
|
CUST
|
Customs |
|
CVR
|
Cockpit voice recorder |
|
CWY
|
Clearway |
|
C ˚
|
Degrees Celsius (Centigrade) |
D
|
D
|
Danger area (followed by identification) |
|
DA
|
Decision altitude |
|
DAH
|
Designated airspace handbook
|
|
DAP
|
Departure and approach procedures |
|
D-ATIS*
|
Data link automatic terminal information service (pronounced ‘dee-atis’) |
|
DCKG
|
Docking |
|
DCMSD
|
Decommissioned |
|
DCPC†
|
Direct controller-pilot communications |
|
DCT
|
Direct (in relation to flight plan clearance and type of approach) |
|
DEC
|
December |
|
DEG
|
Degrees |
|
DEP
|
Depart, departure, departed, departing, departure message |
|
DER
|
Departure end of runway |
|
DES
|
Descend to, descending to |
|
DEST
|
Destination |
|
DETRESFA*
|
Distress Phase |
|
DEV
|
Deviation, deviating |
|
DFDR
|
Direct flight data recorder |
|
DF†
|
Direction finder/finding |
|
DH
|
Decision height |
|
DIF
|
Diffuse |
|
DISP
|
Displaced |
|
DIST
|
Distance |
|
DIV
|
Diversion, divert, diverting |
|
DLA
|
Delay, delayed |
|
DLIC
|
Data link initiation capability |
|
DLY
|
Daily |
|
DME†
|
Distance measuring equipment |
|
DNG
|
Danger, dangerous |
|
DOC
|
Documents |
|
DOM
|
Domestic |
|
DP
|
Dew point temperature |
|
DPT
|
Depth |
|
DR
|
Low Drifting (followed by: D U = dust; SN=snow; SA = sand) |
|
DRG
|
During |
|
DR†
|
Dead reckoning |
|
DS
|
Duststorm |
|
DTAM
|
Descend to and maintain |
|
DTG
|
Date-time group |
|
DTHR
|
Displaced runway threshold |
|
DTRT
|
Deteriorate, deteriorating |
|
DU
|
Dust |
|
DUC
|
Dense upper cloud |
|
DUR
|
Duration |
|
D-VOLMET
|
Data link VOLMET |
|
DVOR
|
Doppler VOR |
|
DZ
|
Drizzle |
E
|
E
|
East, east longitude |
|
EAT
|
Expected approach time |
|
EB
|
Eastbound |
|
EET†
|
Estimated elapsed time |
|
EHF
|
Extremely high frequency 30,000 to 300,000 MHZ) |
|
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 |
|
ENDCE
|
Endurance |
|
ENE
|
East north-east |
|
ENG
|
Engine |
|
ENR
|
En route |
|
EOBT
|
Estimated off blocks time |
|
EPIRB*
|
Electronic position indicating radio beacon (marine term) |
|
EQPT
|
Equipment |
|
ERC†
|
En Route Chart |
|
ERSA*†
|
En Route Supplement Australia |
|
ESE
|
East South-East |
|
EST
|
Estimate, estimate as message type indicator |
|
ETA†
|
Estimated Time of Arrival, Estimating Arrival |
|
ETD†
|
Estimated time of departure, estimating departure |
|
ETO
|
Estimated time over significant point |
|
ETOPS
|
Extended range operations b y aeroplanes with two turbine power units |
|
EV
|
Every |
|
EXC
|
Except |
|
EXER
|
Exercises, exercising, to exercise |
|
EXP
|
Expect, expected, expecting |
|
EXTD
|
Extend, extending, extended |
F
|
F
|
Fixed (chart symbol) |
|
FAC
|
Facility, facilities |
|
FAF
|
Final approach fix |
|
FAP
|
Final approach point |
|
FATO
|
Final approach and take-off area |
|
FAX*
|
Facsimile transmission |
|
FBL
|
Light (to indicate the intensity of WX phenomena, interference or static reports, for example FBL RA = light rain) |
|
FC
|
Funnel cloud (tornado or water spout) |
|
FCST
|
Forecast |
|
FDPS
|
Flight data processing system |
|
FEB
|
February |
|
FEW
|
Few (cloud descriptor) |
|
FFR
|
Flood, fire relief |
|
FG
|
Fog |
|
FIA†
|
Flight information area |
|
FIC†
|
Flight information centre |
|
FIR†
|
Flight information region |
|
FIS†
|
Flight information service |
|
FL
|
Flight level |
|
FLD
|
Field |
|
FLG
|
Flashing |
|
FLR
|
Flares |
|
FLT
|
Flight |
|
FLTCK
|
Flight check |
|
FLUC
|
Fluctuating, fluctuation, fluctuated |
|
FLW
|
Follow(s), following |
|
FLY
|
Fly, flying |
|
FM
|
From |
|
FM
|
From (followed by time weather change is forecast to begin) |
|
FMS†
|
Flight management system |
|
FMU
|
Flow management unit |
|
FN
|
‘Fly neighbourly’ area |
|
FNA
|
Final approach |
|
FPD
|
Flight plan designator |
|
FPL
|
Filed flight plan message |
|
FPM
|
Feet per minute |
|
FPR
|
Flight plan route |
|
FR
|
Fuel remaining |
|
FREQ
|
Frequency |
|
FRI
|
Friday |
|
FRNG
|
Firing |
|
FRQ
|
Frequent |
|
FSL
|
Full stop landing |
|
FSP
|
Fish spotting |
|
FST
|
First |
|
FS†
|
Flight service (in general) |
|
FT
|
Feet |
|
FU
|
Smoke |
|
FXD
|
Fixed |
|
FZ
|
Freezing |
|
FZDZ
|
Freezing drizzle |
|
FZFG
|
Freezing fog |
|
FZL
|
Freezing level |
|
FZRA
|
Freezing rain |
G
|
G
|
Green
|
|
G
|
Variation from mean wind speed (gusts) (MET – in METAR/SPECI and TAF code forms) |
|
GAAP
|
General aviation aerodrome procedures |
|
GAF
|
Graphical area forecasts |
|
GBAS†
|
Ground-based augmentation |
|
GCA†
|
Ground-controlled approach |
|
GEN
|
General |
|
GEO
|
Geographic, true |
|
GES
|
Ground earth station |
|
GFY
|
Glider flying |
|
GLD
|
Glider |
|
GLONASS*
|
Global orbiting navigation satellite system (pronounced ‘glo-nas’) |
|
GLS†
|
GBAS landing system |
|
GND
|
Ground |
|
GNDCK
|
Ground check |
|
GNS
|
Global navigation system |
|
GNSS†
|
Global navigation satellite system |
|
GP
|
Glide path |
|
GP FLG
|
Group flashing (followed by number) (in conjunction with aerodrome lighting) |
|
GPI
|
Glide path intercept |
|
GPS†
|
Global positioning system |
|
GR
|
Hail |
|
GRAD
|
Minimum required climb gradient |
|
GRASS*
|
Grass landing area |
|
GRVL
|
Gravel |
|
GS
|
Ground speed
|
|
GS
|
Small hail and/or snow pellets |
|
GUND
|
Geoid undulation |
|
GWPT
|
Grid point wind and temperature |
H
|
H
|
High pressure are of the centre of high pressure (MET) |
|
H24†
|
Continuous day and night service |
|
HAA
|
Height above aerodrome |
|
HAT
|
Height above threshold |
|
HBN
|
Hazard beacon |
|
HDG
|
Heading |
|
HDS
|
Hours of daylight saving |
|
HEL
|
Helicopter |
|
HF†
|
High frequency ( 3000 to 30,000 KHZ) |
|
HGT
|
Height, height above |
|
HIAL*
|
High intensity approach lighting |
|
HIOL
|
High intensity obstacle lighting |
|
HIRL
|
High intensity runway lighting |
|
HJ†
|
Sunrise to sunset |
|
HLDG
|
Holding |
|
HLS
|
Helicopter landing site |
|
HN†
|
Sunset to sunrise |
|
HO
|
Service available to meet operational requirements |
|
HOSP
|
Hospital aircraft |
|
HPA
|
Hectopascal |
|
HR
|
Hours |
|
HS
|
Homestead |
|
HS
|
Service available during hours of scheduled operations |
|
HSL
|
Hold short lights |
|
HURCN
|
Hurricane |
|
HVY
|
Heavy
|
|
HVY
|
Heavy (to indicate the intensity of WX phenomena, for example HVY RA = heavy rain) |
|
HX
|
No specific working hours |
|
HYR
|
Higher |
|
HZ
|
Haze |
|
HZ
|
Hertz |
|
HZS
|
Horizontal surface |
I
|
IAC
|
Instrument approach chart (followed by name/title) |
|
IAF
|
Initial approach fix |
|
IAL†
|
Instrument approach and landing |
|
IAO
|
In and out of clouds |
|
IAS†
|
Indicated air speed |
|
IBN
|
Identification beacon |
|
IC
|
Ice crystals ( meteorological code) |
|
ICAO*
|
International Civil Aviation Organisation |
|
ICE
|
Icing, ice |
|
ID
|
Identifier, identify |
|
IDENT*
|
Identification |
|
IF
|
Intermediate fix or intermediate approach fix |
|
IFF†
|
Identification friend/foe |
|
IFR†
|
Instrument flight rules |
|
ILS†
|
Instrument landing system |
|
IM
|
Inner marker |
|
IMC†
|
Instrument meteorological conditions |
|
IMG
|
Immigration |
|
IMPR
|
Improve, improving, improvement |
|
IMT
|
Immediate, immediately |
|
INBD
|
Inbound |
|
INCERFA*
|
Uncertainty phase |
|
INC†
|
In cloud |
|
INFO*
|
Information |
|
INOP*
|
Inoperative |
|
INSTL
|
Install, installed, installation |
|
INSTR
|
Instrument |
|
INS†
|
Inertial navigation system |
|
INT
|
Intersection |
|
INTER*
|
Intermittent, intermittently |
|
INTL
|
International |
|
INTRG
|
Interrogator |
|
INTRP
|
Interrupt, interruption, interrupted |
|
INTSF
|
Intensify, intensifying |
|
INTST
|
Intensity |
|
ISA*
|
International standard atmosphere |
|
ISB
|
Independent sideband |
|
ISOL
|
Isolated |
|
IWI
|
Illuminated wind indicator |
J
|
JAN
|
January |
|
J-BAR*
|
Jet barrier |
|
JF
|
Saturday, Sunday and public holidays |
|
JO
|
Monday to Friday except public holidays |
|
JTST
|
Jet stream |
|
JUL
|
July |
|
JUN
|
June |
K
|
KG
|
Kilograms |
|
KHZ
|
Kilohertz |
|
KM
|
Kilometres |
|
KMH
|
Kilometres per hour |
|
KPA
|
Kilopascals |
|
KT
|
Knots |
|
KW
|
Kilowatts |
L
|
L
|
Left (runway identification) |
|
L
|
Low pressure area or the centre of low pressure (MET) |
|
LAHSO
|
Land and hold short operations |
|
LAN
|
Inland |
|
LAT*
|
Latitude |
|
LCA
|
Locally, location, located, local |
|
LDA
|
Landing distance available |
|
LDG
|
Landing |
|
LDI
|
Landing direction indicator |
|
LEN
|
Length |
|
LF
|
Low frequency (30 to 300 KHZ) |
|
LGT
|
Light, lighting |
|
LGTD
|
Lighted |
|
LIH
|
Light intensity high |
|
LIL
|
Light intensity low |
|
LIM
|
Light intensity medium |
|
LIOL
|
Low intensity obstacle lights |
|
LIRL
|
Low intensity runway lights |
|
LJR
|
Low jet route |
|
LLN
|
Low-level navigation ( by the military) |
|
LLO
|
Low-level operations (by the military) |
|
LMT
|
Local mean time |
|
LOC
|
Locally, location, located, local |
|
LOE
|
Lane of entry |
|
LONG*
|
Longitude |
|
LRG
|
Long range |
|
LSALT
|
Lowest safe altitude |
|
LTD
|
Limited |
|
LUL
|
Lowest usable level |
|
LV
|
Light and variable (wind) |
|
LVE
|
Leave, leaving |
|
LVL
|
Level |
|
LYR
|
Layer, layered |
M
|
M
|
Metres (preceded by figures) |
|
M
|
Mach number ( followed by figures) |
|
MAE
|
Men and equipment |
|
MAG
|
Magnetic |
|
MAHF
|
Missed approach holding fix |
|
MAINT
|
Maintenance |
|
MAN
|
Manual |
|
MAP
|
Aeronautical maps and charts |
|
MAP
|
Missed approach procedure |
|
MAPT
|
Missed approach point |
|
MAR
|
March |
|
MAR
|
At sea |
|
MATF
|
Missed approach turning fix |
|
MAX*
|
Maximum |
|
MBST
|
Microburst |
|
MDA
|
Minimum descent altitude |
|
MDF
|
Medium frequency direction finding station |
|
MEA†
|
Minimum en-route altitude |
|
MED
|
Medical |
|
MEHT
|
Minimum eye height over threshold |
|
MET*
|
Meteorological, meteorology |
|
METAR*
|
Aviation routine weather report (in aeronautical meteorological code) |
|
METRAD
|
MET Radar |
|
MET REPORT
|
Aviation routine weather report |
|
MF
|
Medium frequency ( 300 to 3000 KHZ) |
|
MHZ
|
Megahertz |
|
MI
|
Shallow (met) |
|
MIFG
|
Shallow fog |
|
MIL
|
Military |
|
MIN
|
Minutes |
|
MIOL
|
Medium intensity obstacle lights |
|
MIRL
|
Medium intensity runway lights |
|
MISC
|
Miscellaneous |
|
MKR
|
Marker radio beacon |
|
MLJ
|
Military low jet |
|
MLJR
|
Military low jet route |
|
MLS†
|
Microwave landing system |
|
MLW
|
Maximum landing weight |
|
MM
|
Middle marker |
|
MNM
|
Minimum |
|
MNT
|
Monitor, monitoring, monitored |
|
MNTN
|
Maintain, maintained, maintaining |
|
MO
|
Meteorological office |
|
MOA
|
Military operating area |
|
MOC
|
Minimum obstacle clearance (required) |
|
MOD
|
Moderate (to indicate the intensity o f WX phenomena, interface o r static reports; for example, MOD RA = moderate rain) |
|
MON
|
Monday |
|
MON
|
Above mountains |
|
MOPS*
|
Minimum operational performance standards |
|
MOV
|
Move, moved, moving, movement |
|
MOWP
|
Method of working plan |
|
MPS
|
Meters per second |
|
MRG
|
Medium range |
|
MRP
|
ATS/MET Reporting Point |
|
MS
|
Minus |
|
MSA†
|
Minimum sector altitude |
|
MSG
|
Message |
|
MSL
|
Mean sea level |
|
MSSR
|
Monopulse secondary surveillance radar |
|
MT
|
Mountain |
|
MTOW
|
Maximum take-off weight |
|
MTP
|
Maximum tyre pressure |
|
MTW
|
Mountain waves |
|
MVA
|
Minimum vector altitude |
|
MWO
|
Meteorological watch office |
|
MX
|
Mixed type of ice formation (white and clear) |
N
|
N
|
North, north latitude |
|
NAIPS
|
National Aeronautical Information Processing System |
|
NAP
|
Noise abatement procedures |
|
NAT
|
NAVAID training |
|
NAV
|
Navigation |
|
NAVAID
|
Navigation aid |
|
NB
|
Northbound |
|
NBFR
|
Not before |
|
NC
|
No change |
|
NCD
|
No cloud detected (by ceilometer) (in automated METAR/SPECI) |
|
NDB†
|
Non-directional Radio Beacon |
|
NDV
|
No-directional Variation reporting capability (by vismeter) in automated METAR/SPECI) |
|
NE
|
North-east |
|
NEG
|
Negative, no, permission not granted, or that is not correct |
|
NGT
|
Night |
|
NIL*
|
None |
|
NIS
|
NAIPS internet service
|
|
NM
|
Nautical miles |
|
NML
|
Normal |
|
NNE
|
North north-east |
|
NNW
|
North north-west |
|
NOF
|
International NOTAM Office |
|
NOTAM*
|
Notice to airmen |
|
NOV
|
November |
|
NOZ†
|
Normal operating zone |
|
NPA
|
Non-precision approach |
|
NR
|
Number |
|
NS
|
Nimbostratus |
|
NSC
|
Nil significant cloud |
|
NSW
|
Nil significant weather |
|
NTA
|
No TAF amendment |
|
NTL
|
National |
|
NTZ†
|
No transgression zone |
|
NVG
|
Night vision goggles |
|
NW
|
North-west |
|
NXT
|
Next |
O
|
O/R
|
On request |
|
OBS
|
Observe, observed, observation |
|
OBSC
|
Obscure, obscured, obscuring |
|
OBST
|
Obstacle |
|
OBSTR
|
Obstruction |
|
OCA
|
Obstacle clearance altitude |
|
OCA†
|
Oceanic control area |
|
OCC
|
Occulting (light) |
|
OCNL
|
Occasional, occasionally |
|
OCT
|
October |
|
OCTA†
|
Outside control area |
|
OCTR†
|
Outside control zone |
|
OFZ
|
Obstacle free zone |
|
OHD
|
Overhead |
|
OK
|
We agreed, or it is correct |
|
OLDI†
|
On line data interchange |
|
OM
|
Outer marker |
|
OPA
|
Opaque, white type of ice formation |
|
OPMET
|
Operational meteorological |
|
OPN
|
Open, opening, opened
|
|
OPN
|
Operational notification message |
|
OPR
|
Operator, operate, operative, operating, operational |
|
OPS
|
Operations |
|
OT
|
Other times |
|
OTLK
|
Outlook (in SIGMET messages for volcanic ash and tropical cyclones) |
|
OTP
|
On top |
|
OUBD
|
Outboard |
|
OVC
|
Overcast |
|
OW
|
Over water |
P
|
P
|
Prohibited area (followed by identification)
|
|
PAL*
|
Pilot activated lighting |
|
PANS
|
Procedures for air navigation services |
|
PAPI*
|
Precision approach path indicator |
|
PAR
|
Precision approach radar |
|
PARL
|
Parallel |
|
PAX
|
Passengers |
|
PBN
|
Performance-based navigation |
|
PCD
|
Proceed, proceeding |
|
PCL
|
Pilot controlled lighting |
|
PCN
|
Pavement classification number |
|
PER
|
Performance |
|
PERM
|
Permanent |
|
PFR
|
Preferred route |
|
PH
|
Public holiday |
|
PIB
|
Pre-flight information bulletin |
|
PILS
|
Practice ILS |
|
PJE
|
Parachute jumping exercise |
|
PL
|
Ice pellets |
|
PLN
|
Flight plan |
|
PLVL
|
Present level |
|
PN
|
Prior notice required |
|
PNR†
|
Point of no return |
|
PO
|
Dust devils |
|
POB†
|
[Number] persons on board |
|
POSS
|
Possible |
|
PPI†
|
Plan position indicator |
|
PPR
|
Prior permission required |
|
PPSN
|
Present position |
|
PRD
|
Prohibited, restricted and danger areas |
|
PRFG
|
Aerodrome partially covered by fog (meteorological code) |
|
PRI
|
Primary |
|
PRKG
|
Parking |
|
PROB*
|
Probable, probability |
|
PROC
|
Procedure |
|
PROV
|
Provisional |
|
PS
|
Plus |
|
PSG
|
Passing |
|
PSN
|
Position |
|
PSP
|
Pierced steel plank |
|
PSR†
|
Primary surveillance radar |
|
PTBL
|
Portable |
|
PTN
|
Procedure turn |
|
PVT
|
Private |
|
PWR
|
Power |
Q
|
QNH†
|
Altimeter subscale setting t o obtain elevation or altitude |
|
QUAD
|
Quadrant |
R
|
R
|
Red |
|
R
|
Restricted area (followed by number) |
|
RA
|
Rain |
|
RAD
|
Radius |
|
RAFC
|
Regional area forecast centre |
|
RAG
|
Ragged |
|
RAG
|
Runway arresting gear |
|
RAIM*
|
Receiver autonomous intergity monitoring |
|
RAPIC*
|
Radar picture (MET) |
|
RASC*
|
Regional AIS System Centre |
|
RCA
|
Reach cruising altitude |
|
RCC†
|
Rescue Coordination Centre |
|
RCH
|
Reach, reaching |
|
RCL
|
Runway centreline |
|
RCLL
|
Runway centreline lights |
|
RCP
|
Required Communication Performance
|
|
RDL
|
Radial |
|
RDO
|
Radio |
|
RE
|
Recent (to qualify weather phenomena, for example RERA = recent rain) |
|
REC
|
Receive, receiver, received |
|
REDL
|
Runway edge lights |
|
REF
|
Reference to, refer to |
|
REG
|
Registration |
|
RENL
|
Runway end lights |
|
REP
|
Report, reported, reporting, reporting point |
|
REQ
|
Request, requested |
|
RERTE
|
Re-route |
|
RES
|
Reserve fuel |
|
RESA
|
Runway end safety area |
|
RESTR
|
Restrictions |
|
REV
|
Review |
|
REC
|
Regional forecasting centre (MET) |
|
RFF
|
Rescue and fire fighting services |
|
RH
|
Radio height |
|
RHC
|
Right-hand circuit |
|
RIF
|
Reclearance in flight |
|
RIS*
|
Rader/ADS-B Information Service |
|
RL
|
Report leaving |
|
RLA
|
Relay to |
|
RLLS
|
Runway lead-in lighting |
|
RMK
|
Remark(s) |
|
RNAV*
|
Area navigation |
|
RNP
|
Required navigation performance |
|
ROBEX*
|
Regional OPMET bulletin exchanges recommended practices (ICAO) |
|
ROC
|
Rate of climb |
|
ROD
|
Rate of descent |
|
ROFOR*
|
Route forecast (in aeronautical meteorological code) |
|
RPI
|
Runway point of intercept |
|
RPI†
|
Radar position indicator |
|
RPT
|
Regular public transport |
|
RPT
|
Repeat, I repeat |
|
RQ
|
Require(d) |
|
RQMNTS
|
Requirements |
|
RR
|
Report reaching |
|
RSC
|
Rescue sub-centre |
|
RSCD
|
Runway surface condition |
|
RSP
|
Responder beacon system |
|
RSR
|
En-route surveillance radar |
|
RTE
|
Route |
|
RTF
|
Radio telephone/telephony |
|
RTHL
|
Runway threshold light(s) |
|
RTIL
|
Runway threshold identification lights |
|
RTN
|
Return, returned, returning |
|
RTS
|
Return to service |
|
RTZL
|
Runway touchdown zone lights |
|
RVR†
|
Runway visual range |
|
RVSM
|
Reduced vertical seperation minimum |
|
RWS
|
Runway strip |
|
RWY
|
Runway |
S
|
S
|
South, south latitude |
|
SA
|
Sand |
|
SALS
|
Simple approach lighting system |
|
SAR*
|
Search and rescue |
|
SARPS
|
Standards and recommended practices (ICAO) |
|
SARTIME*
|
Time search action required |
|
SAT
|
Saturday |
|
SATCOM*
|
Satellite communication |
|
SB
|
Southbound |
|
SC
|
Stratocumulus |
|
SCT
|
Scattered |
|
SDBY
|
Standby |
|
SDC
|
Standard departure clearance |
|
SE
|
South-east |
|
SEA
|
Sea (in connection with sea-surface temperature and state of the sea) |
|
SEC
|
Seconds |
|
SECT
|
Section, sector |
|
SELCAL*
|
Selective calling system |
|
SEP
|
September |
|
SER
|
Service, servicing, served |
|
SEV
|
Severe (for example, to qualify icing and turbulence report) |
|
SFC
|
Surface |
|
SFL
|
Sequenced flashing lights |
|
SG
|
Snow grains |
|
SH
|
Showers (followed by: RA = rain; SN = snow; PE = ice pellets; GR = hail; GS = small hail and/ or snow pellets; or combinations thereof; for example, SHRASN = showers of rain and snow) |
|
SHF
|
Super high frequent 3,000 to 30,000 MHZ) |
|
SID*
|
Standard instrument departure |
|
SIF
|
Selective identification |
|
SIGMET*
|
Information concerning en-route weather phenomena which may affect the safety of aircraft operations |
|
SIGWX
|
Significant weather |
|
SIMUL
|
Simultaneous, simultaneously |
|
SITREP
|
Situation report |
|
SKC
|
Sky clear |
|
SKED*
|
Schedule, scheduled |
|
SLP
|
Speed limiting point |
|
SLW
|
Slow, slowly |
|
SMCV†
|
Surface movement control vehicles |
|
SMC†
|
Surface movement control |
|
SMR
|
Surface movement radar |
|
SN
|
Snow |
|
SNOWTAM*
|
A special series |
|
SOC
|
Start of climb |
|
SOT
|
Start of TORA (take-off) |
|
SP
|
Single pilot |
|
SPA
|
Sport aviation |
|
SPI
|
Special position indicator
|
|
SPECI*
|
Aviation special weather (in aeronautical meteorological code) |
|
SPFIB
|
Specific preflight information bulletin |
|
SPOT*
|
Spotwind |
|
SQ
|
Squall |
|
SR
|
Sunrise |
|
SRD
|
Standard radar departure |
|
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 arrival route |
|
STD
|
Standard |
|
STF
|
Stratiform |
|
STN
|
Station |
|
STNR
|
Stationary |
|
STODA
|
Supplementary take-off distance |
|
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 |
|
SVCBL
|
Serviceable |
|
SVY
|
Survey operations |
|
SW
|
South-west |
|
SWS
|
Soft wet surface |
|
SWY
|
Stopway |
T
|
T
|
Bearing (true) |
|
T
|
Temperature |
|
TA
|
Transition altitude |
|
TAC*
|
Terminal area chart |
|
TACAN*
|
Tactical air navigation aid |
|
TAF*
|
Aerodrome forecast |
|
TAIL*
|
Tailwind |
|
TAR
|
Terminal area survelliance area |
|
TAS†
|
True airspeed |
|
TAT*
|
Terminal area thunderstorm service (meteorological) |
|
TAX
|
Taxiing, Taxi |
|
TBA
|
To be advised |
|
TC
|
Tropical cyclone |
|
TCAC
|
Tropical cyclone advisory centre |
|
TCAS*
|
Traffic alert and collision avoidance system ( pronounced ‘tee-kas’) |
|
TCH
|
Threshold crossing height |
|
TCTA
|
Trans-continental control area |
|
TCU
|
Towering cumulus |
|
TDO
|
Tornado |
|
TDZ
|
Touchdown zone |
|
TECR
|
Technical reason |
|
TEL
|
Telephone |
|
TEMPO*
|
Temporary, temporarily |
|
TFC
|
Traffic |
|
TFR
|
Terrain following radar ( by the military) |
|
TGL
|
Touch-and-go landing |
|
THR
|
Threshold |
|
THRU
|
Through |
|
THU
|
Thursday |
|
TIBA
|
Traffic information broadcasts by aircraft |
|
TIL*
|
Until |
|
TIP
|
Until past (followed by place name) |
|
TKOF
|
Take-off |
|
TL
|
Until/Till |
|
TLW
|
Time limited WIP (work in progress) |
|
TMA†
|
Terminal control area |
|
TN
|
Indicator for minimum temperature (MET – in TAF code form) |
|
TNA
|
Turn altitude |
|
TNH
|
Turn height |
|
TNS
|
Transitional surface |
|
TOC
|
Top of climb |
|
TODA
|
Take-off distance available |
|
TOP
|
Cloud top |
|
TORA
|
Take-off run available |
|
TP
|
Turning point |
|
TR
|
Track |
|
TRA
|
Temporary reserved airspace |
|
TRAN
|
Transition |
|
TRANS
|
Transmits, transmitter |
|
TRA†
|
Temporary restricted area |
|
TRL
|
Transition level |
|
TROP
|
Tropopause |
|
TS
|
Thunderstorm (followed by: RA = rain; SN = snow; PE = ice pellets; GR = hail; GS=small hail and/or snow pellets; or combinations thereof; for example TSRASN = thunderstorm with rain and snow) |
|
TUE
|
Tuesday |
|
TURB
|
Turbulence |
|
T-VASIS*
|
‘T’ visual approach slope indicator system (pronounced ‘tee-vasis’) |
|
TWR
|
Aerodrome control tower, aerodrome control |
|
TWY
|
Taxiway |
|
TWYL
|
Taxiway link |
|
TX
|
Indicator for maximum temperature MET – in TAF code form) |
|
TYP
|
Type of aircraft |
|
TYPH
|
Typhoon |
U
|
U/S
|
Unserviceable |
|
UAB
|
Until advised by |
|
UDF†
|
UHF direction finding stations |
|
UFN
|
Until further notice |
|
UHDT
|
Unable higher due traffic |
|
UHF†
|
Ultra high frequency ( 300 to 3,000 MHZ) |
|
UIR
|
Upper flight information region |
|
UL
|
Upper limits |
|
UNA
|
Unable |
|
UNAP
|
Unable to approve |
|
UNL
|
Unlimited |
|
UNLC
|
Unlicensed |
|
UNREL
|
Unreliable |
|
UP
|
Unknown precipitation |
|
UTA
|
Upper control area |
|
UTC†
|
Coordinated universal time |
V
|
V
|
Variation from mean wind speed (MET – in METAR/SPECI code forms) |
|
VA
|
Volcanic ash |
|
VAAC
|
Volcanic ash advisory centre |
|
VAL
|
In valleys |
|
VAR
|
Magnetic variation |
|
VASIS*
|
Visual approach slope indicator system |
|
VC
|
Vicinity (of the aerodrome) (followed by: FG = fog; FC = funnel cloud; PO = dust/sand whirls; BLDU = blowing dust; BLSA = blowing sand; BLSN = blowing snow; for example VCFG = vicinity fog) |
|
VCY
|
Vicinity |
|
VDF†
|
VHF direction finding station |
|
VER
|
Vertical |
|
VFR†
|
Visual flight rules |
|
VHF†
|
Very high frequency (30 to 300 MHZ) |
|
VIA
|
By way of |
|
VIP†
|
Very important person |
|
VIS
|
Visibility |
|
VLF
|
Very low frequency (3 to 30 MHZ) |
|
VLR
|
Very long range |
|
VMC†
|
Visual meteorological conditions |
|
VNC
|
Visual navigation chart |
|
VOLMET*
|
Meteorological information for aircraft in flight |
|
VOR†
|
VHF omni-directional radio range (OMNI) |
|
VRB
|
Variable |
|
VTC
|
Visual terminal chart |
|
VTOL
|
Vertical take-off and landing |
|
VV
|
Vertical visibility (MET – in METAR/SPECI and TAF code forms) |
W
|
W
|
West, west longitude |
|
W
|
White |
|
WAC
|
World aeronautical chart – ICAO 1:1,000,000 (followed by name/title) |
|
WAFC
|
World Area Forecast Centre |
|
WATIR
|
Weather and terminal information reciter |
|
WB
|
Westbound |
|
WDI
|
Wind direction indicator |
|
WDSPR
|
Widespread |
|
WED
|
Wednesday |
|
WEF
|
With effect from, effective from |
|
WGS-84
|
World Geodetic System – 1984 |
|
WI
|
Within |
|
WID
|
Width |
|
WIE
|
With immediate effect, effective immediately |
|
WINTEM
|
Forecast upper wind and temperature at specified points (in aeronautical meteorological code) |
|
WIP
|
Work in progress |
|
WKN
|
Weaken, weakening |
|
WNW
|
West north-west |
|
WO
|
Without |
|
WPT
|
Waypoint |
|
WRNG
|
Warning |
|
WS
|
Wind shear |
|
WSW
|
West south-west |
|
WT
|
Weight |
|
WTSPT
|
Water spout |
|
WX
|
Weather |
|
WWW
|
World wide web |
X
|
X
|
Cross |
|
XBAR
|
Crossbar (of approach lighting system) |
|
XNG
|
Crossing |
|
XS
|
Atmospherics |
Y
|
Y
|
Yellow |
|
YCZ
|
Yellow caution zone |
|
YR
|
Your(s) |
Z
|
Z
|
Coordinated universal time (in meteorological messages) |