mechanical interfaces in a backup governing system for a variable pitch propeller between stationary and rotatable propeller sections are avoided in a variable pitch propeller system that includes a backup governing system carried by the propeller hub which is hydraulically interposed between a main control for the propeller and a propeller blade moving , double acting piston . the system includes a spool valve including a spool movable between a plurality of metering positions along with first and second opposing springs applying oppositely directed biasing forces to the valve member . a flyweight assembly is connected to the spool and applies a speed dependent valve positioning force to the spool in opposition to a first of the springs and in addition to the second of the springs . a piston valve is operatively associated with the second spring and operable to change the bias applied by the second spring to the spool . the piston valve includes a valve seat interposed between a transfer bearing and the double acting piston and operable to control the flow of a fine pitch stream to a fine pitch side of the double acting piston . a fluid passage interconnects the piston valve and the spool valve and is arranged so that when the spool valve moves to a predetermined position , the fine pitch stream is applied to the piston valve to initiate backup operation .