Plain English Meaning

A propeller where the angle of the blades can be changed while flying, instead of being permanently fixed at one angle. This lets the pilot get the best performance from the engine whether climbing, cruising, or descending.

Full Definition

A propeller whose blade angle (pitch) can be changed by the pilot during flight, allowing the engine and propeller to operate efficiently across a wide range of airspeeds and power settings. On most modern aircraft, the propeller is governed automatically to maintain a selected RPM, and the pilot adjusts pitch indirectly through a propeller control lever.

Context Anchor

Seen in engine and propeller discussions, especially when comparing fixed-pitch propellers with propellers that can be adjusted for performance.