Cooling of electromechanical actuator with phase change material and thermosyphons containing working fluid

A passively cooled electromechanical actuator is disclosed. The passively cooled electromechanical actuator includes a rotor having an output shaft rotatably received within a stator. A pair of inner supports connect the stator to a pair of mounting platforms. The mounting platforms are attached to the inner surfaces of an aircraft wing and are in thermal communication therewith. A pair of closed, capillary tube thermosyphons containing a working fluid are in thermal communication with the stator, the inner supports and the mounting platforms. During operation, the thermosyphons receive heat from the stator and transport it to the mounting platforms whereupon it is convected or radiated to the atmosphere from the aircraft wings. The inner supports have a phase change material received within for providing temporary thermal energy storage during transient conditions.