Control surface actuator assemblies, aircraft hydraulic systems including the same, and associated aircraft and methods

A control surface actuator assembly for selectively pivoting a flight control surface relative to a support structure comprising:

• a support structure;
• a flight control surface operatively coupled to the support structure and configured to pivot relative to the support structure about a control surface pivot axis;
• a torque-generating hydraulic actuator;
• and
• a variable horn radius (VHR) hydraulic actuator pivotally coupled to the torque-generating hydraulic actuator and operatively coupled to the flight control surface;
• wherein each of the torque-generating hydraulic actuator and the VHR hydraulic actuator includes:
• a respective hydraulic actuator housing and a respective rod that extends at least partially into the respective hydraulic actuator housing, wherein the respective rod is configured to translate relative to the respective hydraulic actuator housing along a respective actuator axis;
• and
• a respective hydraulic valve that regulates a flow of hydraulic fluid relative to the respective hydraulic actuator housing to control a position of the respective rod relative to the respective hydraulic actuator housing;
• wherein the torque-generating hydraulic actuator and the VHR hydraulic actuator are configured to pivot relative to one another about an actuator coupling axis;
• wherein the torque-generating hydraulic actuator is configured to apply a torque to the flight control surface to pivot the flight control surface relative to the support structure;
• and wherein the VHR hydraulic actuator is configured to selectively vary an actuator moment arm length, as measured between the control surface pivot axis and the actuator coupling axis, to at least partially regulate the torque applied to the flight control surface by the torque-generating hydraulic actuator.