| Abbreviation | Definition |
|---|---|
| ATM | Altamira, PA, Brazil |
| ATN | Namatanai, Papua New Guinea |
| ATP | Aitape, Papua New Guinea |
| ATQ | Amritsar, India |
| ATR | Atar, Mauritania |
| ATT | Atmautluak, Alaska USA |
| ATW | Appleton, Wisconsin USA |
| ATY | Watertown, South Dakota USA |
| ATZ | Assiut, Egypt |
| AU | Austral Líneas Aéreas |
| AUA | Aruba, Aruba |
| AUC | Arauca, Colombia |
| AUG | Augusta, Maine USA |
| AUH | Abu Dhabi, United Arab Emirates |
| AUJ | Ambunti, Papua New Guinea |
| AUK | Alakanuk, Alaska USA |
| AUL | Aur Island, Marshall Islands |
| AUP | Agaun, Papua New Guinea |
| AUQ | Autonoma, Marquesas Islands |
| AUR | Aurillac, France |