Film cooled components

A film-opposed component subject to heating by hot fluid flowing therepast, the component having wall means with one side thereof being a first surface subject to said heating and the other side thereof being a second surface subject to cooling by flow of pressurized coolant therepast, the wall means having a plurality of film cooling holes therethrough connecting the first and second surfaces to allow coolant to flow through said holes onto the first surface for film-cooling of the same, wherein the holes comprise in coolant flow series an inlet aperture on the second surface, a convergent portion, a coolant flow metering restriction, a divergent portion and an outlet aperture on the first surface, the metering restriction connecting the narrowest parts of the convergent and divergent portions, wherein no line of said convergent portion is co-linear with a line of said divergent portion.