Abstract: An actuator assembly that has a constant net pressure area telescoping piston. The actuator assembly has a cylindrical housing; nesting, telescoping pistons; a central plug; an outer cap; and a vent. The cylindrical housing has an interior surface and a base that terminates at an open end. The nesting, telescoping pistons are located in the housing and can extend past the housing open end. The telescoping pistons have an outer piston slidably sealed against the housing and an inner piston that is slidably sealed against the outer piston. The outer piston has a first end proximal to the housing base, and a second end distal to the housing base. The inner piston has an open end proximal to the housing base, and a closed end distal to the housing base. The central plug extends from the base and into the telescoping pistons. The central plug is in pressurized communication with the inner piston and is engagable with a pressurized fluid source. The outer cap has a first and a second member.