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Abbreviations Used in Aviation

Decoder:  Braking Action | Weather Contractions | Abbreviations list | NOTAMs Contractions | Aircraft

You can use Ctrl+F to find a specific abbreviation. 
Other contractions used by the National Weather Service and FAA are available at the links above.  If you don't find what you're looking for, contact me and i will research it for you. 

Want the complete reference guide?  Click the green thumbnail to the above right. 

ABV - above
AC - Advisory Circular

ACFT - Aircraft
AD - Airworthiness Directive
ADI - attitude direction indicator
ADF - automatic direction finder
ADIZ - air defense identification zone
A/FD - Airport/Facility Directory
AFM - Airplane Flight Manual
AFSS - Automated Flight Service Station
AGI - Advanced Ground Instructor
AGL - above ground level
AIM - Aeronautical Information Manual
AIRMET - Airman's Meteorological Info
ALS - approach light system
ALSF-1 - standard 2400' high-intensity approach lighting system with sequenced flashers (Category I configuration) 
ALSF-2 - standard 2400' high-intensity approach lighting system with sequenced flashers (Category II configuration) 
AME - aviation medical examiner
AMEL/S - airplane multi-engine land/sea
AOA - angle of attack
AOE - airport of entry 
A&P - Airframe & Powerplant
APCH - approach 
APU - auxiliary power unit
ARTC - air route traffic control 
ARTCC - Air Route Traffic Control Center 
ASL - above sea level (Canada)
ASOS - Automated Surface Observing System
ASR - airport surveillance radar
ASRS - Aviation Safety Reporting System
A/T - auto throttle
ATA - actual time of arrival
ATC - air traffic control
ATE - actual time enroute
ATIS - Automatic Terminal Info Service
ATP - Airline Transport Pilot
AWOS - Automatic Weather Observing System 
BFR - Biennial Flight Review
BHP - Brake Horsepower
C - Celcius
CAS - calibrated airspeed
CAT II - Category II
CAVU - Ceiling and visibility unlimited
CDI - Course Deviation Indicator
CFI - Certificated Flight Instructor
CFIT - controlled flight into terrain
CFR - Code of Federal Regulations
CG - center of gravity
CHT - cylinder head temperature
CO - carbon monoxide CO2 carbon dioxide
CONSOL or CONSOLAN - a low or medium frequency long range navigational aid
CONUS - Continental U.S.  
COP - change over point
CRM - crew resource management
CTAF - common traffic advisory frequency
CVR - cockpit voice recorder
CWA - center weather advisory
DA - density altitude
DALR - dry adiabatic lapse rate
DF/Steer - direction finding/steering
DG - directional gyro, heading indicator
DH - decision height
DME - distance measuring equipment compatible with TACAN
DOT - Department of Transportation
DUAT(S) - Direct User Access Terminal (System)
DVFR - defense VFR
EAS - equivalent airspeed
EFAS - enroute flight advisory service
EFIS - electronic flight instrument system
EFC - expect further clearance
EGT - exhaust gas temperature
ELT - emergency locator transmitter
ETA - estimated time of arrival
ETE - estimated time enroute
F - Farenheit
FA - area forecast report
FAA - Federal Aviation Administration
FAF - final approach fix
FAR - Federal Aviation Regulation
FBO - fixed base operator
FCC - Federal Communications Commission
FD - winds aloft report
FDC - Flight Data Center (FAA)
FDR - flight data recorder
FE - flight engineer
FL - flight level
FM - fan marker
FMS - flight management system
FO - first officer
FOD - foreign object debris
FPM - feet per minute
FSDO - Flight Standards District Office (FAA)
FSS - flight service station
FYI - For your information 
G - gravitational force
GA - general aviation
GMT - Greenwich Mean Time
GP - glide path/ GS slope
GPH - gallons per hour
GPS - global positioning system
GPU - ground power unit
GPWS - ground proximity warning system
HAA - height above airport
HAT - height above threshold
HF - high frequency
HIRL - high-intensity runway light system
HIWAS - Hazardous In-Flight Weather Advisory Service
HP - horsepower
HSI - horizontal situation indicator
HUD - heads-up display
IAF - initial approach fix
IAP - instrument approach procedure
IAS - indicated airspeed
ICAO - International Civil Aviation Organization. 
IFR - instrument flight rules
IGI - Instrument Ground Instructor
ILS - instrument landing system
IM - ILS inner marker
IMC - instrument meterological conditions
INOP - inoperative
INS - intertial navigation system
INT - intersection
ISA - International Standard Atmosphere
IR - military training route - instrument
KIAS - Knots, Indicated Airspeed
KHZ - kilohertz
LAA - local airport advisory
LAAS - local area augmentation system (GPS)
LAHSO - land & hold short operations
LAT - latitude
LBS - pounds
LDA - localizer-type directional aid
LF - low frequency
LFR - low-frequency radio range
LLWS - low level wind shear
LLWAS - low level windshear alert system
LLZ - localizer
LMM - compass locator at middle marker
LNAV - lateral navigation
LOC - localizer
LOM - compass locator at outer marker
LONG - longitude
LOP - line of position
LORAN - long range radio aid to navigation
M - mach number
MAA - maximum authorized IFR altitude. 
MALS - medium intensity approach light system. 
MALSR - medium intensity approach light system with runway alignment indicator lights
MAP - missed approach point
MB - magnetic bearing
MCA - minimum crossing altitude
MDA - minimum descent altitude
MEA - minimum en route IFR altitude

MFD - multi-function display
MEI - multi engine instructor
MEL - minimum equipment list (91.213)
METAR - meteorological aerodrome report
MH - magnetic heading
MHZ - megahertz
MIRL - medium intensity runway lights
MM - ILS middle marker
MOA - military operations area
MOCA - minimum obstruction clearance altitude
MP - manifold pressure
MPH - miles per hour
MRA - minimum reception altitude
MSA - minimum safe altitude
MSL - mean sea level
MTR - military training route (see IR, VR)
MVA - minimum vectoring altitude
NA - not authorized
NACO - National Aeronautical Charting Office (FAA)
NAVAID - navigational aid, NDB, VOR, etc
NDB(ADF) - nondirectional beacon (automatic direction finder)
NDH - no damage history
NCFT - non federal control tower
NM - nautical mile
NOAA - National Oceanic and Atmospheric Administration  
NOPT - no procedure turn required or authorized
NORDO - no radio
NOTAM - notice to airman
NPRM - notice of proposed rulemaking
NTSB - National Transportation Safety Board
NWS - National Weather Service
OAT - outside air temperature
OBS - omni-bearing selector
OEI - one engine inoperative
OM - ILS outer marker
OROCA - off route obstruction clearance altitude
OTS - out of service
PAR - precision approach radar
PCL - pilot controlled lighting
PF - pilot flying
PFD - primary flight display
PIC - pilot in command
PIREP - Pilot weather report  
PM - pilot monitoring
PNF - pilot not flying
POH - pilot's operating handbook
PSI - pounds per square inch
PT - procedure turn
PTS - practical test standards

RAIL - runway alignment indicator light system
RAIM - receiver autonomous integrity monitoring (GPS)
RB - relative bearing
RBN - radio beacon
RCLM - runway centerline marking
RCLS - runway centerline light system
RCO - remote communications outlet
REIL - runway end identification lights
RMK - remark
RMI - radio magnetic indicator
RNP - required navigational performance
RPM - rotations per minute
RR - low or medium frequency radio range station
RV - radar vector
RVR - runway visual range as measured in the touchdown zone area
RVSM - reduced vertical separation minimum
SALR - saturated adiabatic lapse rate
SALS - short approach light system
SALSF - SALS with sequenced flashing lights
SAR - search and rescue
SDF - simplified directional facility
SIC - second in command
SIGMET - significant meteorological information
SLP - sea level pressure
SM - statute mile
SMOH - since major overhaul
SODA - statement of demonstrated ability
SOP - Standard operating procedure  
SPOH - since prop overhaul
SSALS - simplified short approach light system. 
SSALSR - simplified short approach light system with runway alignment indicator lights
STAR - standard terminal arrival route
STOL - short take off & landing
SUA - special use airspace
SVFR - special VFR
TACAN - tactical air navigational aid, a UHF military nav aid
TAF - terminal aerodrome forecast
TAS - true airspeed
TBO - time between overhaul
TC - true course
TCAS - traffic alert & collision avoidance system 
TCH - threshold crossing height
TDZE - touchdown zone elevation
TDZL - touchdown zone lights
TFR - temporary flight restriction
TH - true heading
TPA - traffic pattern altitude
TRACON - terminal radar approach control
TRSA - terminal radar service area
TSO - technical standard order
TTSN - total time since new
TVOR - terminal VHF omnirange station
TX - transmit or transponder
UHF - ultra-high frequency
UTC - universal coordinated time
V Speeds see r-vspeed.htm
VASI - visual approach slope indicator
VDP - visual descent point
VFR - visual flight rules
VHF - very high frequency
VMC - Visual meteorological conditions  
VNAV - vertical navigation
VOR - VHF omnirange station. 
VORTAC - co-located VOR and TACAN
VR - military training route - VFR
VSI - vertical speed indicator
VV - vertical visibility
WA - airmet
WAAS - wide area augmentation system (GPS)
WAC - world aeronautical chart
WH - hurricane advisory
WPT - waypoint
WS - sigmet
WST - convective sigmet
WW - Severe Weather Watch 
Z - zulu time


A - Amber
Be - Beige
Bk - Black
B - Blue
Br - Brown
Gd - Gold
Gy - Gray
G - Green
O - Orange
P - Purple
R - Red
S - Silver
T - Tan
V - Violet 
W - White
Y - Yellow


  • "Shall" is used in an imperative sense;
  • "May" is used in a permissive sense to state authority or permission to do the act prescribed, and the words 
  • "no person may * * *" or "a person may not * * *" mean that no person is required, authorized, or permitted to do the act prescribed
  • "Includes" - "includes but is not limited to"

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