'Variable Pitch Propellers’ means a propeller, the pitch setting of which changes or can be changed, when the propeller is rotating or stationary. This includes:-
a.) A propeller, the pitch setting of which is directly under the control of the flight crew (controllable pitch propeller).
b) A propeller, the pitch setting of which is controlled by a governor or other automatic means which may be either integral with the propeller or a separately mounted equipment and which may or may not be controlled by the flight crew (constant speed propeller).
c) A propeller, the pitch setting of which may be controlled by a combination of the methods of a. and b.
