A blade or vane arrangement for a gas turbine engine has an array of aerofoils mounted to respective platforms about an axis and defining a passage through which a working gas flow passes. The arrangement has a datum and the aerofoil has a radial span. Each aerofoil has pressure side, a suction side, a leading edge region and a leading edge foot extending from the leading edge region, the leading edge foot has a ridge line. The platform defines a channel and a platform leading edge, the channel has a minimum radial height line, and the platform leading edge partly defines an outlet through which a secondary flow passes. The ridge line is aligned generally in the direction of the working gas flow and the minimum radial height line is aligned generally in the direction of the secondary flow.