Abstract: A propeller shaft assembly for an aircraft engine includes a shaft having a bore extending through the shaft at a front end thereof, the front end of the shaft having an outer surface facing radially outwardly from the shaft and an inner surface spaced apart from the outer surface and facing radially inwardly to the bore. A front flange extends radially outwardly on the outer surface, the front flange defining a hub side surface adapted to abut with a propeller hub. A reinforcement rib extends radially inwardly towards a central axis of the shaft. At least part of the reinforcement rib is radially aligned with the front flange.

Abstract: A propeller shaft assembly for an aircraft engine includes a shaft having: an annular wall extending circumferentially about a shaft axis and circumscribing a hollowed interior defining a cavity in a front end portion of the shaft, the annular wall having an outer surface and an inner surface facing radially inwardly to the cavity; and a front flange projecting radially outwardly from the annular wall. The front flange includes a hub side surface defining an interface plane and adapted to abut with a propeller hub. The shaft also includes a reinforcement web defining an end wall of the cavity, the reinforcement web extending radially inwardly from the inner surface of the annular wall. At least part of the reinforcement web is radially aligned with the front flange. At least one perforation extends axially through the reinforcement web.

Abstract: A propeller shaft assembly for an aircraft engine includes a shaft having a bore extending through the shaft at a front end thereof, the front end of the shaft having an outer surface facing radially outwardly from the shaft and an inner surface spaced apart from the outer surface and facing radially inwardly to the bore. The shaft has a front flange extending radially outwardly on the outer surface, the front flange having a base merging with the outer surface of the shaft. A sleeve is coupled to the shaft within the bore by an interference fit between the sleeve and the shaft, at least part of the sleeve axially aligned with the front flange. The sleeve axially extends from a front to a rear sleeve end, the rear sleeve end axially offset from the engine side surface of the front flange at the base of the front flange.

Abstract: A Woodruff key system includes a rotatable shaft having a keyseat defined therein. The keyseat includes a pocket engaged with the Woodruff key, a first keyseat extension extending in a first axial direction from the Woodruff key relative to the shaft, and a second keyseat extension extending in a second axial direction opposite the first axial direction from the Woodruff key relative to the shaft. Respective depths of the first and second keyseat extensions are less than a depth of the pocket of the keyseat.

Abstract: An apparatus for a gas turbine engine includes a shaft base, a flange and a plurality of lobes. The shaft base extends axially along an axis between a shaft first end and a shaft second end. The flange is connected to the shaft base at the shaft first end. The flange projects radially out from the shaft base. The flange includes a plurality of fastener apertures, and the fastener apertures include a first fastener aperture. The lobes are arranged circumferentially about the axis. Each of the lobes is connected to and projects radially away from the shaft base. Each of the lobes is connected to and projects axially out from the flange. The lobes include a first lobe and a second lobe. The first fastener aperture is arranged circumferentially between the first lobe and the second lobe. The second lobe radially overlaps the first fastener aperture.

Abstract: An apparatus is provided for a gas turbine engine. This gas turbine engine apparatus includes a shaft base, a flange and a plurality of lobes. The shaft base extends axially along an axis between a shaft first end and a shaft second end. The flange is connected to the shaft base at the shaft first end. The flange projects radially out from the shaft base. The flange includes a plurality of fastener apertures, and the fastener apertures include a first fastener aperture. The lobes are arranged circumferentially about the axis. Each of the lobes is connected to and projects radially away from the shaft base. Each of the lobes is connected to and projects axially out from the flange. The lobes include a first lobe and a second lobe. The first fastener aperture is arranged circumferentially between the first lobe and the second lobe. The second lobe radially overlaps the first fastener aperture.

Abstract: Woodruff key coupling systems for torque transmission are provided. An example Woodruff key system includes a rotatable shaft having a keyseat defined therein. The keyseat includes a pocket engaged with the Woodruff key, a first keyseat extension extending in a first axial direction from the Woodruff key relative to the shaft, and a second keyseat extension extending in a second axial direction opposite the first axial direction from the Woodruff key relative to the shaft. Respective depths of the first and second keyseat extensions are less than a depth of the pocket of the keyseat.