PROPELLER CONTROL UNIT

A propeller control unit (PCU) (21) for controlling pitch angles of blades (17) of a propeller (19), has: a pitch angle actuator (24); a servo valve (25) hydraulically connected to the pitch angle actuator (24) and to a first hydraulic fluid source (13); and a feather valve (26a) having a body (B) movable within a cavity, the feather valve having a first actuation port (26f) and a second actuation port (26g) both in fluid communication with the cavity, the body (B) between the first actuation port (26f) and the second actuation port (26g), the body (B) being movable to selectively hydraulically connect the pitch angle actuator (24) to the servo valve (25) through the feather valve (26a) or to hydraulically connect the pitch angle actuator (24) to a drain line (32) through the feather valve (26a), the first actuation port (26f) and the second actuation port (26g) hydraulically connected to a second hydraulic fluid source (RGB, 13g, 15, AGB, EP) independent from the first hydraulic fluid source (13).