A †
- A1海域 (Sea Area 1)
- A2海域 (Sea Area 2)
- ACAS (Airbone Collision Aviodance System)
- AC信号 (Auxiliary Channel Signal)
- ACシンボル (Auxilialy Channel Symbol)
- ATCRBS (Air Traffic Control Radar Beacon System)
- ATCトランスポンダ (Air Traffic Controle Transponder)
- A型ワイヤレスマイク (Wireless Microphone A Type)