- A/C
Aircraft
- A/D
Aerodrome
- A/P
airplane (US), aeroplane (ICAO)
- A/P
Autopilot
- AACO
Arab Air Carriers Organisation
- AAPA
Association of Asia Pacific Airlines
- AASA
Airline Association of Southern Africa
- ABTA
Association of British Travel Agents
- ACAC
Arab Civil Aviation Commission
- ACARS
Aircraft Communications Addressing and Reporting System
- ACARS
Aircraft Communication and Addressing Reporting System
- ACAS
Airborne Collision Avoidance System
- ACAS
Airborne Collision Avoidance System
- ACAS
Airborne Collision-Avoidance System (ICAO)
- ACC
Active Clearance Control
- ACC
Airport Consultative Committee (IATA)
- ACFT
Aircraft
- ACI
Airports Council International
- ACI
Airports Council International
- ACMS
Aircraft Condition Monitoring System
- ACP
Audio Control Panel
- ACS
Audio Control System
- AD
Airworthiness Directive
- ADAHRS
Air Data and Attitude Heading Reference System
- ADC
Air Data Computer
- ADC
Air Data Computer
- ADF
Automatic Direction Finder
- ADF
Automatic Direction Finder
- ADI
Attitude Director Indicator
- ADI
Attitude Director Indicator
- ADIRS
Air Data Inertial Reference System
- ADIRU
Air Data Inertial Reference Unit
- ADM
Air Data Module
- ADS
Either; Automatic Dependant Surveillance or Air Data System
- ADS
Automatic Dependent Surveillance
- ADS-A
Automatic Dependant Surveillance /Address
- ADS-B
Automatic Dependant Surveillance-Broadcast
- ADV
German Airports Association
- AEA
Association of European Airlines
- AECMA
European Association of Aerospace Industries
- AFCAC
African Civil Aviation Commission
- AFCS
Automatic Flight Control System
- AFCS
Automatic Flight Control System
- AFD
Autopilot Flight Director
- AFDC
Autopilot Flight Director Computer
- AFDS
Autopilot Flight Director System
- AFDS
Autopilot Flight Director System
- AFE
Above Field Elevation
- AFIS
Either; Automatic Flight Information Service or Airborne Flight Information System
- AFRAA
African Airlines Association
- AFS
Aeronautical Fixed Service
- AFTN
Aeronautical Fixed Telecommunications Network
- AFTN
Aeronautical Fixed Telecommunication Network
- AGACS
Automatic Ground-Air Communications System, is also known as ATCSS or data link
- AGC
Automatic Gain Control
- AGL
Above ground level
- AGM
Annual General Meeting (IATA)
- AHC
Attitude Heading Control
- AHRS
Attitude and Heading Reference Systems
- AHRS
Attitude Heading Reference System
- AIP
Aeronautical Information Publication
- ALC
Automatic Level Control
- ALPA
Air Line Pilots Association
- ALS
Approach Lighting System
- ALT
Either; Altimeter or Altitude
- ALT Hold
Altitude Hold Mode
- ALTA
Asociación Latinoamericana del Transporte Aéreo
- ALTS
Altitude Select
- AMLCD
Active Matrix Liquid Crystal Display
- AMSL
Above Mean Sea Level
- ANC
Active Noise Cancellation
- ANN
Annunciator- caution warning system normally containing visual and audio alerts to the pilot
- ANR
Active Noise Reduction
- ANS
Air Navigation Services
- ANSP
Air Navigation Service Provider
- ANT
Antenna
- AOA
Angle of Attack
- AOC
Air Operator's Certificate
- AOC
Air Operator's Certificate
- AOM
Airport/Aerodrome Operating Minima
- AP
Autopilot
- APC
Autopilot Computer
- API
Advance Passenger Information
- APIS
Advance Passenger Information Systems
- APS
Autopilot System
- APU
Auxiliary Power Unit
- APU
Auxiliary Power Unit
- AR
Authorization Required
- ARINC
Aeronautical Radio, Incorporated (ARINC
- ARINC
Aeronautical Radio Inc (US)
- ARINC
Aeronautical Radio Inc.
- ARTCC
Air Route Traffic Control Centers
- ASA
Air Services Agreement
- ASAS
Airborne Separation Assurance System
- ASD
Aircraft Situation Display
- ASDA
Association for Scientific Development of Air Traffic Management in Europe
- ASDL
Aeronautical Satellite Data Link
- ASEAN
Association of South East Asian Nations
- ASECNA
Agence pour la Sécurité de la Navigation Aérienne en Afrique et à Madagascar
- ASI
Airspeed Indicator
- ASL
Above sea level
- ASM
Airspace management
- ASO
Agency Services Office
- ASPA
Association of South Pacific Airlines
- ASR
Airport Surveillance Radar
- ASTA
American Society of Travel Agents
- ASU
Avionics Switching Unit
- AT-One
Strategic Alliance between DLR and NLR on ATM research and development
- ATA
Air Traffic Association
- ATA
Air Transport Association of America
- ATAC
Air Transport Association of Canada
- ATAG
Air Transport Action Group
- ATB
Air Transport Association of America
- ATC
Air Traffic Control
- ATC
Air Traffic Control
- ATCRBS
Air Traffic Control Radar Beacon System
- ATCSS
Air Traffic Control Signaling System
- ATFM
Air Traffic Flow Management
- ATI
Unit of measure for instrument size, a standard 3¨û cutout is a 3ATI
- ATIS
Automatic Terminal Information Service
- ATK
Available Tonne Kilometre
- ATM
Air Traffic Management
- ATM
Air Traffic Management
- ATN
Aeronautical Telecommunication Network
- ATN
Aeronautical Telecommunication Network
- ATNS
Air Traffic and Navigation Services
- ATPL
Airline Transport Pilot Licence
- ATS
Air Traffic Services
- ATS
Air Traffic Services
- ATS/DS
Air Traffic Services Direct Speech
- ATSP
Air Traffic Service Providers
- AUC
Air Transport Users Council
- AWB
Air Waybill
- AWG
American Wire Gauge
- Avionics
Aviation electronics
