Back-up featherer

A back-up featherer is provided for an engine arrangement having a main hydraulic actuator which angularly displaces propellers of a propeller assembly of the engine arrangement. The engine arrangement further has one or more fluid supply lines for transferring hydraulic fluid between a hydraulic pressure power source located on a static structure of the engine arrangement and the main hydraulic actuator. The back-up featherer has a back-up actuator assembly for angular displacement of the propellers, the back-up actuator assembly rotating with the propeller assembly. The back-up featherer further has a signal detector that is operatively connected to the back-up actuator assembly and rotates with the propeller assembly. The back-up featherer further has a back-up rotating coupling. A static side of the back-up rotating coupling is mounted to the static structure of the engine arrangement and communicates with a regulator located on a static structure of the engine arrangement. A rotating side of the back-up hydraulic rotating coupling rotates with the propeller assembly and communicates with the signal detector. The back-up actuator assembly angularly displaces the propellers when the signal detector detects a signal from the regulator to displace the propellers.