Electric machine cooling plate for aircraft powerplant

A method of manufacture, comprising:

• forming a metal cooling plate for an aircraft powerplant using investment casting to provide the metal cooling plate with a cast monolithic body;
• wherein the metal cooling plate comprises a fluid cooling circuit internal to the cast monolithic body, the fluid cooling circuit includes an inlet manifold, an outlet manifold and a plurality of heat exchange passages, each of the plurality of heat exchange passages comprises a longitudinal centerline and extends longitudinally along the longitudinal centerline from the inlet manifold to the outlet manifold, the plurality of heat exchange passages comprise a first heat exchange passage, and the first heat exchange passage is configured with a plurality of first cooling elements arranged longitudinally along the longitudinal centerline of the first heat exchange passage;
• and
• wherein the metal cooling plate is configured to support an electric machine controller, the electric machine controller includes a controller housing and controller circuitry, the controller housing is removably attached to the metal cooling plate and overlaps the plurality of heat exchange passages, the controller circuitry is disposed within an interior of the controller housing, and the controller circuitry is configurable in thermal communication with the metal cooling plate through a wall of the controller housing when supported by the metal cooling plate.