Definition
A propeller whose blade angle is set by the manufacturer and cannot be adjusted by the pilot in flight or on the ground. Because the blade angle is a single fixed value, the propeller is optimized for one phase of flight (typically either climb or cruise) and operates less efficiently in others.
Plain English
A propeller with blades permanently set at one angle. The pilot has no control over the blade angle -- it's the same on takeoff, climb, cruise, and descent.
Context Anchor
Common on many light-sport aircraft, basic trainers, and simple airplanes; encountered during preflight, aircraft familiarization, and performance discussions.
Derivation
Pitch' here refers to the angle of the propeller blades relative to the plane of rotation -- borrowed from the idea of a screw's pitch, which determines how far it advances per turn. A blade at a steeper pitch takes a bigger 'bite' of air per revolution. 'Fixed' simply means that angle does not change.
Why Pilots Care
Provides simplicity, lower cost, and reduced maintenance for light-sport aircraft, though it limits efficiency across varying flight conditions compared with variable-pitch designs.
Analogy
It is like riding a bicycle with one gear. You can still speed up or slow down, but you cannot shift gears to match every hill or straightaway.
Intuition Check
“Pitch” here does not mean sound. It means the angle of the propeller blades and how they bite into the air. “Fixed” does not mean the propeller does not spin. It means the blade angle stays set.
Example Sentence 1
Most training aircraft are equipped with a fixed pitch propeller, so the pilot manages engine power using only the throttle.
Example Sentence 2
During preflight, the student checked that the fixed pitch propeller had no nicks or cracks along the leading edges.