| 1 | AYS | Awsaj Aviation Services | Designator L9 recalled by IATA | LAR | AVCODES |
| 2 | AYS | Madagasikara Airways | IATA: 7D, Ceased operations. | RM | AVCODES |
| 3 | AYS | Awsaj Aviation Services | | | ICAO1 |
| 4 | AYSC | AYSCUE DISTRIBUTING CO INC | | | SCAC3 |
| 5 | AYSC | ANAYAS TRUCKING | | | SCAC4 |
| 6 | AYSD | AT YOUR SERVICE DELIVERIES INC | | | SCAC4 |
| 7 | AYSE | AT YOUR SERVICE EXPRESS | | | SCAC3 |
| 8 | AYSF | ANDYS SEAFOOD CO INC | | | SCAC3 |
| 9 | AYSH | AMOLYNTOS SHIPPING CO. LTD | | | SCAC3 |
| 10 | AYSH | AMYRA SHIPPING S A | | | SCAC4 |
| 11 | AYSL | AT YOUR SERVICE LIMOUSINE INC | | | SCAC3 |
| 12 | AYSL | AMERICAN YEAST SALES | | | SCAC4 |
| 13 | AYSM | AGRI-PLASTICS MFG DIVISION OF POLYD | | | SCAC4 |
| 14 | AYSN | A S A P DELIVERY SERVICE INC | | | SCAC3 |
| 15 | AYSQ | ALBURY AND SHULER TRUCKING INC | | | SCAC4 |
| 16 | AYSS | Allegheny & South Side | 1/1975-1/1980 | | NAKINA |
| 17 | AYSS | Allegheny & South Side | 1/75-1/80 | | NRHS |
| 18 | AYSS | ALLEGHENY & SOUTH SIDE RAILROAD | | | PWRC |
| 19 | AYSS | Allegheny and South Side Railway | | | RSRV |
| 20 | AYST | AMETHYST MARITIME CORPORATION | | | SCAC3 |
| 21 | AYSV | AT YOUR SERVICE LIMO | | | SCAC3 |
| 22 | AYSV | AT YOUR SERVICE LIMO | | | SCAC4 |
| 23 | AYSW | AYERS STEAMSHIP CO INC | | | PWRC |
| 24 | AYSW | AYERS STEAMSHIP CO INC | | | SCAC3 |
| 25 | AYSW | AYERS STEAMSHIP CO INC | | | SCAC4 |
| 26 | AYSX | Allegheny Steel Co. | 8/1920 | | NAKINA |
| 27 | AYSX | ALLEGHENY STEEL CO. | | | PWRC |
