| 1 | AY | Finnair Oyj | ICAO: FIN, Callsign: Finnair, IATA Prefix: 105, | FIN | AVCODES |
| 2 | AYA | Federal Aviation Administration (FAA) Academy | Callsign: Academy Air, | USA | AVCODES |
| 3 | AYAC | AMAYA CURIEL Y COMPANIA/PETREOS DEL | | | SCAC4 |
| 4 | AYAF | ARMY & AIR FORCE EXCHANGE SERVICE ( | | | SCAC3 |
| 5 | AYAI | AYA INTERNATIONAL INC | | | SCAC4 |
| 6 | AYAL | AYALA, MANUEL | | | SCAC3 |
| 7 | AYAL | AYALA, MANUEL TRUCKING | | | SCAC4 |
| 8 | AYAM | AYAMSA | | | SCAC3 |
| 9 | AYAN | AYAN TRAVEL INC | | | SCAC3 |
| 10 | AYAP | AMAYA TRANSPORTATION | | | SCAC4 |
| 11 | AYB | Force Terrestre Belge | Callsign: Belgian Army, | B | AVCODES |
| 12 | AYB | Belgian Army | | | ICAO1 |
| 13 | AYBL | ANTHONY, BRETT LESLIE | | | SCAC4 |
| 14 | AYC | Aviacion Y Comercial S.A. (Aviaco) | IATA: AO, Callsign: Aviaco, Merged into Iberia w.e.f. 01 September 1999. | E | AVCODES |
| 15 | AYC | Aya Aviation | | IL | AVCODES |
| 16 | AYCE | AIRE Y CARGAMENTO EXPRESS | | | SCAC3 |
| 17 | AYCE | AINSLEY, SANDRA GALLERY | | | SCAC4 |
| 18 | AYCH | AYERS/CHAIRMAKERS INC | | | SCAC3 |
| 19 | AYCK | AYCOCK INC | | | SCAC3 |
| 20 | AYCO | AYCOCK INC | | | SCAC4 |
| 21 | AYCP | ABERNATHY COMPANY | | | SCAC4 |
| 22 | AYCS | ANDYS CHARTER SERVICE LLC | | | SCAC4 |
| 23 | AYCX | The Aycock Co. | added 7/1961; 7/1965; eliminated 10/1965 | | NAKINA |
| 24 | AYCX | R.L. Aycock Co. | 7/1937-1/1945; 1/1946 (not listed) | | NAKINA |
| 25 | AYCX | R.L. Aycock Co. | Apr-38 | | NRHS |
| 26 | AYCX | The Aycock Co. | 7/65; eliminated 10/65 | | NRHS |
| 27 | AYCX | AYCOCK CO. | | | PWRC |
| 28 | AYD | Aladia Airlines, S.A. de C.V. | IATA: 9A, Callsign: Airlines Aladia, Suspended operations in October 2008. | MEX | AVCODES |
| 29 | AYD | Aladia Airlines | | | ICAO1 |
| 30 | AYDG | AGILITY DEFENSE & GOVERNMENT SERVIC | | | SCAC4 |
| 31 | AYDN | AYYILDIZ DENIZCILIK NAKLIYAT SANAYI | | | SCAC4 |
| 32 | AYDS | ANYTIME DELIVERY SYSTEMS OF NEW ENG | | | SCAC3 |
| 33 | AYDV | ANYTIME DELIVERY SERVICE INC | | | SCAC3 |
| 34 | AYE | Yunnan Yingan Airlines Co., Ltd | IATA: YI, Callsign: Air Ying An, Founded in 2005. AOC issued on 19 January 2005. Ceased operations on 01 December 2015. | PRC | AVCODES |
| 35 | AYEC | AFFINITY EXPRESS LLC | | | SCAC4 |
| 36 | AYEL | AYERS, ELDON D | | | SCAC3 |
| 37 | AYEL | ALL CITY LOGISTICS LLP | | | SCAC4 |
| 38 | AYEM | ABF FREIGHT SYSTEM INC | | | SCAC4 |
| 39 | AYEQ | ACADEMY EXPRESS INC | | | SCAC4 |
| 40 | AYES | AYERS & MADDUX INC | | | SCAC3 |
| 41 | AYES | ALLSTATE STEEL COMPANY INC | | | SCAC4 |
| 42 | AYFI | ARROWKAY FARMS INC | | | SCAC4 |
| 43 | AYFM | AYCO FARMS INC | | | SCAC4 |
| 44 | AYFP | ANYTIME FUEL PROS LLC | | | SCAC4 |
| 45 | AYG | Yangon Airways Limited | IATA: HK, Callsign: Air Yangon, IATA designator changed to YH w.e.f. 15 June 2009. | MYA | AVCODES |
| 46 | AYG | Yangon Airways Limited | IATA: YH, Callsign: Air Yangon, Name changed to Air Thanlwin Holding Company Ltd in February 2014. IATA designator changed from HK* w.e.f. 15 June 2009. | MYA | AVCODES |
| 47 | AYG | Air Thanlwin Holding Company Limited | IATA: YH, Callsign: Royal Bird, Name changed from Yangon Airways Limited in February 2014. IATA Designator changed to ST. IATA designator changed from HK* w.e.f. 15 June 2009. | MYA | AVCODES |
| 48 | AYG | Air Thanlwin Holding Company Limited | IATA: ST, Callsign: Royal Bird, Name changed from Yangon Airways Limited in February 2014. IATA Designator changed from YH*. ICAO designator changed to RTL. IATA designator changed from HK* w.e.f. 15 June 2009. | MYA | AVCODES |
| 49 | AYGC | ALLY LOGISTICS | | | SCAC4 |
| 50 | AYGM | AYALA, GERONIMO | | | SCAC4 |
| 51 | AYGO | ANYTHING GOES | | | SCAC3 |
| 52 | AYGS | AYER & GOSS INC | | | SCAC4 |
| 53 | AYGW | AMOYSAILING MARITIME CO LTD | | | SCAC4 |
| 54 | AYH | Avioandes S.A. | Callsign: Andes, | EC | AVCODES |
| 55 | AYHP | AYESH TRANSPORT | | | SCAC4 |
| 56 | AYJ | Zeman Nextgen | Callsign: Alley Jet, | D | AVCODES |
| 57 | AYJT | AMAYA, J TOWING | | | SCAC4 |
| 58 | AYK | Aykavia Aircompany | | AM | AVCODES |
| 59 | AYK | Aykavia Aircompany | | | ICAO1 |
| 60 | AYKI | ANYAMA TRUCKING INCORPORATED | | | SCAC4 |
| 61 | AYKM | ACKLEY TRUCKING-ACKLEY MOVING SERVI | | | SCAC4 |
| 62 | AYL | Alpine Air Pvt. Ltd. | IATA: N6, Callsign: Alpine Nepal, Suspended operations. | NEP | AVCODES |
| 63 | AYL | A YANKEE LINE INC | | | SCAC4 |
| 64 | AYLA | AYALA COLON, LUIS A SUCRS INC | | | SCAC3 |
| 65 | AYLA | ASBURY LOGISTICS LLC | | | SCAC4 |
| 66 | AYLI | ASHLEY LOGISTICS INC | | | SCAC4 |
| 67 | AYLN | ALMONY, L G & SONS INC | | | SCAC4 |
| 68 | AYLP | ALLIED ENERGY CORPORATION | | | SCAC4 |
| 69 | AYLS | ANTHONY, LINDA S | | | SCAC4 |
| 70 | AYLT | ANANIAS MARINE COMPANY LTD CYPRUS | | | SCAC3 |
| 71 | AYM | Airman, S.L. | Callsign: Airman, | E | AVCODES |
| 72 | AYM | Airman, S.L. | | | ICAO1 |
| 73 | AYMD | ANTHONYS MOVING & DELIVERY SERVICE | | | SCAC3 |
| 74 | AYMG | ARE YOU MOVING AND STORAGE CO | | | SCAC3 |
| 75 | AYMG | AYER MOVING & STORAGE CO INC | | | SCAC4 |
| 76 | AYMI | ATMIC | | | SCAC4 |
| 77 | AYMS | AYER MOVING & STORAGE INC | | | SCAC3 |
| 78 | AYMS | AYERS MARITIME SERVICES INC | | | SCAC4 |
| 79 | AYMU | {LLC "AYAMTRANSSERVICE"};ZIPCODE=677005 | | RUS | BIC |
| 80 | AYMV | ALYESKA MOVING SERVICE INC | | | SCAC3 |
| 81 | AYN | Atlantic Airlines, S.A. | Callsign: Atlantic Nicaragua, | NIC | AVCODES |
| 82 | AYN | Atlantic Airlines, S.A. | | | ICAO1 |
| 83 | AYNC | ALASKA YUKON NAVIGATION COMPANY | | | SCAC3 |
| 84 | AYNO | AYERS STEAMSHIP AGENCY INC | | | SCAC3 |
| 85 | AYNO | ANDY TRANSPORT INC | | | SCAC4 |
| 86 | AYOC | AYERS OIL COMPANY | | | SCAC4 |
| 87 | AYOS | ARROYOS TRUCKING SA DE CV | | | SCAC4 |
| 88 | AYOT | ALLEGHENY OCEAN TRANSPORT INC | | | SCAC4 |
| 89 | AYP | Aero Lloyd Austria Luftfahrt GmbH | IATA: HG, Callsign: Austria Lloyd, Name changed to flyniki / NL Luftfahrt GmbH | A | AVCODES |
| 90 | AYP | flyniki / NL Luftfahrt GmbH | IATA: HG, Callsign: flyniki, ICAO designator changed to NLY. Name changed from Aero Lloyd Austria Luftfahrtb GmbH | A | AVCODES |
| 91 | AYPI | ANTHONY T PRODUCTS INC | | | SCAC4 |
| 92 | AYPL | AGILITY PROJECTS LOGISTICS | | | SCAC4 |
| 93 | AYR | British Aerospace Flying College Limited | Callsign: Cygnet, Name changed to BAe Systems Flight Training (U.K.) Limited. | GB | AVCODES |
| 94 | AYR | British Aerospace Flight Training (U.K.) Limited | Callsign: Cygnet, Name changed from British Aerospace Flying College Limited. Name changed to BAe Systems Flight Training (U.K.) Limited. | GB | AVCODES |
| 95 | AYR | BAe Systems Flight Training (U.K.) Limited | Callsign: Cygnet, Name changed from British Aerospace Flight Training (U.K.) Limited and previously British Aerospace Flying College Limited. | GB | AVCODES |
| 96 | AYR | Flight Training Europe S.L. | Callsign: Cygnet, Name changed from BAe Systems Flight Training (U.K.) Limited and previously British Aerospace Flight Training (U.K.) Limited and previously British Aerospace Flying College Limited. | E | AVCODES |
| 97 | AYR | Flight Training Europe | | | ICAO1 |
| 98 | AYRA | AYERS, ROY A | | | SCAC3 |
| 99 | AYRK | ALYS-TAR TRUCKING | | | SCAC4 |
| 100 | AYRM | AYERS MARITIME SERVICES INC | | | SCAC3 |
