Abstract: An aircraft firewall feedthrough device for accommodating a feedthrough member extending through an aperture of a firewall of an aircraft is provided. The device includes a plate configured to be attached to the firewall, a first tubular portion extending from a first side of the plate, a second tubular portion extending from a second side of the plate, and a grommet. The plate includes a feedthrough aperture. The first tubular portion, the second tubular portion and the feedthrough aperture cooperatively define a through passage for accommodating the feedthrough member. The grommet is retained inside the through passage. The grommet includes a hole for accommodating the feedthrough member through the grommet.

Abstract: An aircraft engine comprises an engine case, the engine case flange(s). A harness of wires extends in proximity to the engine case. The harness of wires includes two or more metal shield sleeves externally covering a bundle of wires in a longitudinal direction, the metal shield sleeves being at least partially electrically insulated from one another. A conductive contact between the at least one flange and at least one of the metal shield sleeve.

Abstract: A blade angle feedback ring assembly for an aircraft engine propeller having adjustable angle blades is provided. The feedback ring assembly comprises a feedback ring coupled to rotate with the propeller, the engine configured such that a first electrically-conductive path is defined between the propeller and the engine via the feedback ring, and an electric current conduction element provided between the propeller and the engine to define a second electrically-conductive path between the propeller and the engine in parallel to the first path, the second electrically-conductive path configured with a lower electrical resistance to conduction between the propeller and the engine than the first electrically-conductive path.