Definition
The pilot interface panel used to select, engage, and adjust the operating modes of a flight director and/or autopilot system. Through the mode controller, the pilot chooses what the automation will do — for example, hold a heading, capture and track a course, climb or descend at a selected vertical speed, or capture and hold a selected altitude.
Plain English
The control panel where the pilot tells the autopilot or flight director what to fly. Push a button to pick a mode, turn a knob to set a value (like a heading or altitude), and the system flies accordingly.
Context Anchor
Found in discussions of flight director and autopilot operation, usually as part of the controls the pilot uses before or during flight to set the desired guidance mode.
Derivation
‘Mode’ comes from Latin ‘modus’, meaning ‘a way’ or ‘manner of doing something’. A mode controller is literally the device that selects which way the autopilot will fly the airplane.
Why Pilots Care
It lets the pilot activate automated flight modes that reduce workload and maintain precise control during instrument procedures.
Intuition Check
Do not think of the mode controller as just an on/off switch. It selects the specific job the guidance system will try to do.
Example Sentence 1
After leveling off at cruise altitude, the pilot used the mode controller to engage altitude hold and select the next heading.
Example Sentence 2
Prior to the ILS approach, the mode controller was set to approach mode so the autopilot could capture the localizer and glideslope.