Definition
An aerodynamic and inertial force acting on a rotating propeller blade that tries to twist the blade toward a flatter (lower) pitch angle. It is generated by the centrifugal effect of the spinning blade's mass attempting to align itself in the plane of rotation.
Plain English
When a propeller spins, each blade is pulled outward by the same effect you feel when you swing a weight on a string. That outward pull tries to twist each blade flat, into the plane it is spinning in, which means flattening its pitch.
Context Anchor
Seen in propeller theory, constant-speed propeller systems, and aircraft maintenance discussions about the forces acting on propeller blades.
Derivation
Centrifugal comes from Latin centrum (center) and fugere (to flee) -- literally 'fleeing the center.' The name captures what the force does: the spinning mass of the blade tries to flee outward from the hub, and that outward pull is what twists the blade flat.
Why Pilots Care
This force is one of the three main influences on blade angle in constant-speed propellers and must be balanced by the governor for stable RPM control.
Intuition Check
Centrifugal Twisting Force does not mean the blade is being bent or visibly warped. It means the spinning blade has a turning tendency that tries to move it toward a lower, flatter angle.
Example Sentence 1
Centrifugal twisting force tries to rotate the propeller blades toward low pitch whenever the engine is running.
Example Sentence 2
During feathering, hydraulic pressure overcomes the centrifugal twisting force to turn the blades edgewise to the airflow.