Plain English Meaning

A propeller whose blades can be rotated to a different angle, either on the ground by a mechanic or in flight by the pilot, so the propeller works efficiently at different speeds and power settings.

Full Definition

A propeller whose blade angle (pitch) can be changed to suit different phases of flight. The term covers two distinct designs: ground-adjustable propellers, where the blade angle is set by a mechanic on the ground and remains fixed in flight, and controllable-pitch propellers, where the pilot can change the blade angle in flight using a cockpit control. In current usage, 'adjustable-pitch propeller' most often refers to a controllable-pitch system, including the constant-speed propeller found on most complex aircraft.

Context Anchor

Seen in propeller and discussions, especially when comparing fixed-pitch, adjustable-pitch, and .