air-flow indicator

instantaneous vertical speed indicator / instantaneous vertical-speed indicator (IVSI)

oxygen flow indicator

air traffic flow management (ATFM)

Main Air Traffic Flow Management Centre (MATFMC)

air flow

air flow duct

air-flow metering unit

corrected air flow

ram-air flow

air flow rate

aerial refueling / air refueling / in-flight refueling (IFR) / air-to-air refueling (AAR)

air combat capable helicopter / air-to-air capable helicopter

air support field pack, field pack air support, airborne / para (air support) / Pathfinder Bergen

artificial horizon (gyro horizon/ attitude indicator)

desiccant indicator

gyro course indicator

indicator console

indicator lamp

indicator light

indicator system

performance indicator

radiac computer-indicator

range height indicator (RHI) scope

target indicator

telltale indicator

turbine inlet temperature indicator

vertical gyro indicator

vertical scale indicator

counter indicator

gyroscope course indicator scale

zone-beat indicator

fire extinguishing system indicator disc