| 1 | AYC | Aviacion Y Comercial S.A. (Aviaco) | IATA: AO, Callsign: Aviaco, Merged into Iberia w.e.f. 01 September 1999. | E | AVCODES |
| 2 | AYC | Aya Aviation | | IL | AVCODES |
| 3 | AYCE | AIRE Y CARGAMENTO EXPRESS | | | SCAC3 |
| 4 | AYCE | AINSLEY, SANDRA GALLERY | | | SCAC4 |
| 5 | AYCH | AYERS/CHAIRMAKERS INC | | | SCAC3 |
| 6 | AYCK | AYCOCK INC | | | SCAC3 |
| 7 | AYCO | AYCOCK INC | | | SCAC4 |
| 8 | AYCP | ABERNATHY COMPANY | | | SCAC4 |
| 9 | AYCS | ANDYS CHARTER SERVICE LLC | | | SCAC4 |
| 10 | AYCX | The Aycock Co. | added 7/1961; 7/1965; eliminated 10/1965 | | NAKINA |
| 11 | AYCX | R.L. Aycock Co. | 7/1937-1/1945; 1/1946 (not listed) | | NAKINA |
| 12 | AYCX | R.L. Aycock Co. | Apr-38 | | NRHS |
| 13 | AYCX | The Aycock Co. | 7/65; eliminated 10/65 | | NRHS |
| 14 | AYCX | AYCOCK CO. | | | PWRC |
