| Code | Description |
|---|
| AAA | Associated Aviation Act. (1960 - 2002) |
| AAB | Abelag Aviation AG (2016 - ) |
| AAB | Antilles Air Boats Inc. (1960 - 2002) |
| AAE | AAA Airlines (1960 - 2002) |
| AAI | Audi Air Inc. (1983 - 1989) |
| AAL | Argosy Air Lines Inc. (1960 - 2002) |
| AAP | Armstrong Air Service Inc. (1985 - 1989) |
| AAR | Altair Airlines Inc. (1960 - 1986) |
| AAT | Air Sunshine Inc. (1983 - ) |
| AAV | Alpine Air (1984 - 2002) |
| AAZ | Alaska Aeronautical Indust. (1960 - 1987) |
| ABH | Air Bahia (1960 - 2002) |
| ABI | Airbama Incorporated (1960 - 2002) |
| ABO | Aeronaves Boringuena Inc. (1960 - 2002) |
| ACA | Alaska Central Airways Inc. (1960 - 2002) |
| ACD | Academy Airlines (1981 - 1986) |
| ACG | Air Cargo Express Inc. (1960 - 2001) |
| ACH | Island Airlines Hawaii Inc. (1960 - 2002) |
| ACI | AAA-Action Air Carrier Inc. (1960 - 2002) |
| ACK | Air Central Inc. (1960 - 2002) |
| ACL | Check-Air Inc. (1981 - 1986) |
| ACN | Alliance Airlines (1985 - 2002) |
| ACO | Air Cargo Enterprises Inc. (1960 - 2002) |
| ACP | Air Chaparral Inc. (1960 - 2002) |
| ACS | Alamo Commuter Airlines (1960 - 2002) |
| ACT | Air Central Inc. (1960 - 2002) |
| ACW | Transwest Air Express (1981 - 1986) |
| ADV | Advantage Airlines (1992 - 2002) |
| AEC | Astec Air East Inc. (1960 - 2002) |
| AEO | Aero Coach (1986 - 2002) |
| AEX | Air Excursions LLC (2001 - 2003) |
| AFA | American Flag Airlines Inc. (1960 - 2002) |
| AFS | Arcata Flying Service (1983 - 2002) |
| AGA | Air Cargo America Inc. (1960 - 2002) |
| AGL | Atlantic Gulf Airlines (1983 - 1984) |
| AHA | Air Alpha (1992 - 2002) |
| AHC | Air Hawaii (1960 - 1987) |
| AIA | All Island Air (1960 - 2002) |
| AIC | Air Caribbean (1960 - 2002) |
| AIE | Air Express Inc. (1960 - 2002) |
| AIG | Airgo Inc. (1981 - 1986) |
| AIK | Air Ketchum Idaho Inc. (1999 - 2002) |
| AIM | Air Mont. Inc. (1960 - 2002) |
| AIN | Air Indiana (1960 - 2002) |
| AIT | Airways International (1986 - 2002) |
| AIY | Alliance Air (1992 - 2002) |
| AKS | Alaska Seaplane Service (1997 - 2003) |
| ALE | Air-Lift Associates Inc. (1960 - 2002) |
| ALI | Brandt Air (1960 - 2002) |
| ALK | Air Link Airways (1986 - 2002) |
| ALL | All Seasons Air Pacific (1960 - 2002) |
| ALS | Air L.A. (1986 - 1996) |
| ALT | Altus Airlines (1981 - 2002) |
| ALU | Aleutian Air (1988 - 2002) |
| ALX | Atlanta Express (1981 - 2002) |
| AMA | North American Airlines Inc. (1960 - 2002) |
| AMI | American Inter-Island Inc. (1960 - 2002) |
| AMR | AvAir (1985 - 1988) |
| AMT | American Air Transport (1981 - 1986) |
| AMW | Air Midwest Inc. (1985 - 2002) |
| ANB | Air Nebraska Inc. (1960 - 2002) |
| ANC | Atlantic Air (1981 - 2002) |
| AND | Southcentral Air Inc. (1960 - 2000) |
| ANE | Pacific Wings Airlines (1960 - 2005) |
| ANI | Dash Air Corporation (1982 - 2002) |
| ANM | Airways Of New Mexico Inc. (1960 - 2002) |
| ANO | Metro Air Northeast Vermont (1960 - 2002) |
| ANT | Air North/Nenana (1960 - 2002) |
| AOI | Trans New York (1960 - 2002) |
| AON | Action Airlines (1985 - 2002) |
| AOR | Air New Orleans (1981 - 2002) |
| APE | Air Cape (1987 - 2002) |
| APH | Alpha Air (1985 - 2002) |
| API | Arizona Pacific Inc. (1960 - 2002) |
| APL | Appalachian Flying Service (1960 - 2002) |
| APN | Aspen Airways Inc. (1991 - 2002) |
| APS | Air Spirit Inc. (1984 - 2002) |
| APY | Air Polynesia Inc. (1960 - 2002) |
| ARA | Air Resorts Airlines (1982 - 2002) |
| ARB | Air Caribe International (1987 - 2002) |
| ARI | Arizona Aero Corp. (1960 - 2002) |
| ARO | Air Oregon (1960 - 2002) |
| ARP | Airspur Helicopters Inc. (1984 - 2002) |
| ARR | Arrowhead Airways Inc. (1960 - 2002) |
| ARS | Air Sedona (1983 - 2002) |
| ARZ | Arizona Airways (1992 - 1996) |
| ASD | Amistad Airlines (1960 - 2002) |
| ASE | Arctic Circle Air Service (1985 - 2003) |
| ASP | Asap Air Inc. (1960 - 2002) |
| AST | Astro Airways (1960 - 2002) |
| ASU | Air South (1981 - 2002) |
| ASW | Sunrise Airlines Inc. (2002 - 2003) |
| ASW | Scenic Airlines (1990 - 2002) |
| ATA | Atlantic Southeast Airlines (1960 - 1993) |
| ATD | Atlantic Coast Airlines (1992 - 2002) |
| ATN | Air Atlantic Airlines Inc. (1960 - 2002) |
| ATO | Pacific National Airways (1960 - 2002) |
| ATS | Atlantis Airlines Inc. (1960 - 2002) |
| ATT | Aerotransit Inc. (1960 - 2002) |
| ATX | Air Carolina (1960 - 2002) |
