A compressor aerofoil for a turbine engine includes a tip portion with a tip wall which extends from the aerofoil leading edge to the aerofoil trailing edge. The tip wall defines a squealer which extends between the leading edge the trailing edge. A shoulder is provided on one of the suction surface wall or pressure surface wall which extends between the leading edge and the trailing. A transition region tapers from the shoulder in a direction towards the tip wall. The other of the suction surface wall or pressure surface wall extends towards the tip wall.

A compressor aerofoil for a turbine engine includes a tip portion with a tip wall which extends from the aerofoil leading edge to the aerofoil trailing edge. The tip wall defines a squealer which extends between the leading edge the trailing edge. A shoulder is provided on one of the suction surface wall or pressure surface wall which extends between the leading edge and the trailing. A transition region tapers from the shoulder in a direction towards the tip wall. The other of the suction surface wall or pressure surface wall extends towards the tip wall.

A variable displacement exhaust turbocharger according to at least one embodiment comprises: a plurality of nozzle vanes; an annular drive ring; and a lever plate fitted at one end in a groove portion disposed in the drive ring via a connecting pin portion and connected at another end to each nozzle vane. The value of dimensionless slippage S between the groove portion and the connecting pin portion is equal to or less than 0.0016. The dimensionless slippage S is represented by a certain equation.