Abstract: A fan for gas turbine engine that includes hub and annular array of fan blades mounted to hub and extending radially outwardly from hub, each fan blade includes blade root. The hub includes a plurality of hub grooves having shape complimentary to shape of blade root and each hub groove receives and radially retains one blade root. A slot is provided on the suction side and on the pressure side of each blade root. Plurality of keys is provided, each key engages with slots in one blade root and with corresponding hub groove so as to axially retain fan blade. The key includes two arms and joining member, two arms are received in slots provided on blade root and joining member extends between the arms. Interface is defined between key arms and slots in blade root, and greater or equal percentage of interface is curved than is planar.

Abstract: Fan for gas turbine engine includes hub and annular array of fan blades mounted to hub and extending radially outwardly from hub, each fan blade includes blade root. The hub includes plurality of hub grooves having shape complimentary to shape of blade root and each hub groove receives and radially retains one blade root. A slot is provided on the suction side and on the pressure side of each blade root. Plurality of keys is provided, each key engages with slots in one blade root and with corresponding hub groove so as to axially retain fan blade. The key includes two arms and joining member, two arms are received in slots provided on blade root and joining member extends between the arms. Interface is defined between key arms and slots in blade root, and greater or equal percentage of interface is curved than is planar.

Abstract: A method of forming an internal structure in a hollow component that includes the steps of forming an assembly having first, second, and third plates the first and second plates each with a substantially planar surface and a surface that includes at least one protrusion and is on the exterior facing surfaces of the assembly. The third plate is sandwiched between the first and second plates. The method also includes the steps of selectively bonding portions of the third plate to sections of the first and second plates substantially opposite the at least one protrusions of the first and second plates; and forming the assembly against a die such that the at least one protrusions of the first and second plates are transferred from the exterior facing surfaces to the interior facing surfaces of the first and second plates.

Abstract: A rotor blade, a rotor disc (24) or load bearing assembly having at least one bearing surface (22) for contact with a corresponding bearing surface (28). At least one selected area of the bearing surface (30,32) which, in operation, is an area of alternating stress greater than about 50 MPa (peak to peak), is configured to have a co-efficient of friction lower than the remainder of the bearing surface (34). The selected area (30,32) having a co-efficient of friction lower than the remainder of the bearing surface (34) may be provided by the application of a dry film lubricant, with the remaining area(s) (34) of said bearing surfaces (22) being substantially free of the said coating.