Ground-adjustable propeller

A ground-adjustable propeller is a simple type of aircraft variable-pitch propeller where the blade angle can be adjusted between pre-set limits of fine and coarse pitch.

[1] As its name implies, a ground-adjustable propeller may be adjusted only when the aircraft is on the ground and when the engine is not running.

A ground-adjustable propeller allows pitch changes to be made, although not in flight, to optimise the aircraft for current payload and flying conditions.

After a flight, if, say, climb seemed too sluggish, the pitch angle may have been set too coarse and would need to be made finer.

The person making the adjustments would be advised to do so in small increments until a satisfactory outcome were reached.