Definition
A remote control unit is a panel-mounted control head that allows the pilot to operate an avionics box (radio, transponder, navigation receiver, etc.) that is physically located elsewhere in the aircraft, typically in an avionics bay or behind the panel.
Plain English
A small control head in the cockpit that lets the pilot run a piece of equipment installed somewhere else in the airplane, without having to reach the equipment itself.
Context Anchor
Seen in aircraft equipment descriptions, especially where a radio, display, sensor, or other system is controlled from a separate cockpit panel.
Derivation
From 'remote' (Latin remotus, 'moved away') plus 'control unit.' The name simply describes its job: a control unit that operates something at a distance.
Why Pilots Care
Knowing a switch or knob is on an RCU rather than on the equipment itself helps the pilot understand the system layout, troubleshoot failures, and brief avionics operation correctly.
Intuition Check
Remote does not necessarily mean wireless or hand-held. Here it means the control unit is separate from the equipment it controls.
Example Sentence 1
The transponder is mounted in the tail, and the pilot operates it through the RCU on the center panel.
Example Sentence 2
During preflight checks the pilot verified radio settings through the RCU mounted on the aft console.