Patent ID: 8540480

Claim:
An aerofoil for a gas turbine engine, the aerofoil comprising: at least one wall defining an interior along which in use cooling air flows in a first direction, the at least one wall defining a passage extending from an interior surface of the at least one wall to an exterior surface of the at least one wall to permit in use a cooling air flow in a second direction therealong, wherein the passage includes an inlet area defined by the interior surface, the inlet area having a shape which is elongated along one axis, the elongate axis of the inlet area extending along or being substantially parallel with the first cooling air flow direction, an external fluid flowing across the exterior surfaces of the at least one wall in a third direction, cooling air on exiting the passage, flowing in said third direction, the passage includes an outlet area, which is defined by the exterior surface, and which has a shape which is elongated along one axis so that the elongate axis of the outlet area extends along or substantially parallel to the third direction, the elongate axis of the inlet area and the outlet area are oriented at different angles to each other, the elongate axis of the inlet area lies on a first plane, and the first and second directions lie on the same plane, and the passage converges from the inlet area to the outlet area along the first plane.