Abstract: An aerofoil blade/disc assembly suitable for the compressor or turbine of a gas turbine engine comprising a rotor disc which has a circumferential, part-circular cross-section channel provided in its periphery for the reception of the correspondingly part-circular cross-section roots of an annular array of aerofoil blades. The arrangement is such that upon disc rotation, the aerofoil blades pivot with respect thereto until their platforms sealingly engage a circumferential radially extending flange provided on the disc periphery. A seal is provided between the aerofoil blades and the disc which reduces the leakage of gases between the aerofoil blade roots and their retaining channel.