Definition
A cockpit indicator that displays information through direct mechanical linkage or movement of physical parts, rather than through electronic processing or digital display. The needles, drums, or pointers are driven by springs, gears, gyros, diaphragms, or cables connected to the system being measured.
Plain English
A gauge that shows readings using moving physical parts driven directly by what they are measuring, instead of using electronics or a digital screen.
Context Anchor
Seen inside the airplane when checking the position or status of items such as landing gear, flaps, trim, doors, or locks.
Derivation
‘Mechanical’ comes from the Greek mēkhanē, meaning ‘machine’ or ‘device with moving parts.’ A mechanical indicator is literally an indicator that works through moving parts, distinguishing it from electronic indicators that work through circuits and screens.
Why Pilots Care
Mechanical indicators provide independent backup information that does not rely on electrical power.
Intuition Check
Do not assume mechanical indicator means any instrument in the cockpit. Here it means a physical indication produced by movement of parts, not just an electronic message or light.
Example Sentence 1
The airspeed indicator is a mechanical indicator driven by air pressure acting on a diaphragm inside the case.
Example Sentence 2
In the event of an electrical failure, the mechanical indicators continued to provide essential flight information.