Definition
A flight control system in which the pilot's inputs at the controls are transmitted directly to the control surfaces by physical linkages -- typically a combination of rods, cables, pulleys, chains, and bellcranks -- without hydraulic, electric, or electronic assistance.
Plain English
When the pilot moves the yoke or rudder pedals, those movements travel through metal rods and cables to physically pull or push the control surfaces on the wings and tail. Nothing electronic or powered sits in between.
Context Anchor
Seen when learning how cockpit controls connect to the aircraft’s wings and tail, and during preflight checks for free and correct control movement.
Derivation
Mechanical' comes from the Greek mekhanikos, meaning 'relating to machines.' The name highlights that the system is purely mechanical -- moving parts only -- with no power assistance or electronic signaling involved.
Why Pilots Care
These systems give direct feel to the controls but require physical effort and regular inspection for cable tension and wear.
Analogy
It is like a bicycle brake cable: when you squeeze the handle, a physical cable carries that motion to the brake. In a mechanical flight control system, the pilot’s input is carried by connected parts to the aircraft’s control surfaces.
Intuition Check
Mechanical does not mean the system is powered by an engine or that it controls the aircraft automatically. Here it means the pilot’s input is passed along by physical moving parts.
Example Sentence 1
Most training aircraft use a mechanical flight control system, so the controls feel heavier as airspeed increases.
Example Sentence 2
During the preflight inspection the pilot checked the cables of the mechanical flight control system for proper tension.