| Abbreviation | Definition |
|---|---|
| AC | Advisory Circular |
| AC | Alternating Current |
| ACAA | Allegheny County Airport Authority |
| ACAC | AVIC i Commercial Aircraft Company |
| ACAG | Aviation Community Advisory Group |
| ACAM | Atlantic Canada Aviation Museum |
| ACAP | Airport Capital Assistance Program |
| ACARE | Advisory Council for Aircraft Innovation and Research in Europe |
| ACARS | Aircraft Communication Addressing and Reporting System |
| ACARS | ARINC Communications Addressing and Reporting System |
| ACAS | Airborne collision avoidance system |
| ACC | Area Control Center |
| ACC | Active Clearance Control |
| ACC | Airports Consultants Council |
| ACCAM | Australian Certificate of Civil Aviation Medicine |
| ACCB | Aircraft Change Control Board |
| ACCLRM | Accelerometer |
| ACCP | Aviation Career Continuation Pay |
| ACDL | Airport Concessions and Development Limited |
| ACE | Actuator control electronics |