Propulsor external hydraulic control system

A propeller assembly for a rotary wing aircraft, the propeller assembly comprising:

• a rotor hub configured to be rotated along a rotor axis by an engine or a motor, the rotor hub comprising a hub arm;
• a rotor blade rotatably coupled to the hub arm about a hub arm axis;
• a pitch change shaft configured to translate along the rotor axis;
• a pitch beam coupled to the pitch change shaft and comprising a first arm extending radially from the pitch change shaft;
• a first guide rod fixedly coupled to the rotor hub and in sliding contact with the pitch beam, the first guide rod extending parallel to the rotor axis, wherein the first guide rod extends across an inner cavity of the rotor hub;
• and
• a pitch link coupled to a distal end of the first arm of the pitch beam and to the rotor blade, the pitch link configured to rotate the rotor blade about the hub arm axis to adjust a pitch of the rotor blade when the pitch change shaft translates along the rotor axis.

A rotary wing aircraft comprising:

• a fuselage;
• a main rotor assembly coupled to the fuselage comprising at least one main rotor blade configured to be coupled to a main rotor hub;
• and
• a propulsor assembly coupled to the fuselage and comprising:
• a hydraulic pump;
• an engine or a motor configured to rotate a propulsor rotor hub about a propulsor rotor axis, the propulsor rotor hub comprising a rotor shaft and a central opening each positioned around the propulsor rotor axis;
• a hydraulic actuation cylinder positioned in the central opening of the propulsor rotor hub and comprising an inner cavity;
• a first hydraulic line extending through the rotor shaft from the hydraulic pump to a first chamber of the inner cavity of the hydraulic actuation cylinder;
• a second hydraulic line extending through the rotor shaft from the hydraulic pump to a second chamber of the inner cavity of the hydraulic actuation cylinder;
• and
• a pitch change assembly configured to translate along the propulsor rotor axis in response to a difference in hydraulic pressure between the first chamber and the second chamber, wherein a proximal end of the pitch change assembly is positioned in the inner cavity of the hydraulic actuation cylinder, the pitch change assembly comprising:
• a piston coupled to a proximal end of a pitch change shaft, the proximal end of the pitch change shaft defining the proximal end of the pitch change assembly;
• a pitch beam coupled to a distal end of the pitch change shaft;
• and
• a first guide rod fixedly coupled to the propulsor rotor hub and in sliding contact with the pitch beam, the first guide rod extending parallel to the propulsor rotor axis, wherein the first guide rod extends across an interior cavity of the propulsor rotor hub.