Abstract: An aerofoil for a gas turbine engine turbine rotor blade or stator vane is subject to film cooling by multiple rows of small cooling air exit apertures in the exterior surface of the blade or vane. Each exit aperture is supplied with cooling air through at least two holes extending from the aperture through the wall of the blade or vane to interior chambers or passages. The holes are mutually intersecting and their intersection forms the exit apertures and defines a flow constriction for controlling the flow rate of cooling air through the holes and out of the aperture. If the holes' centerlines intersect behind the plane of the exterior surface by an optional distance, the flow constriction is spaced apart from the exit aperture and is within the wall thickness, the exit aperture being enlarged. These film cooling hole configurations reduce the liability of the holes to block up due to contamination by environmental debris.