Abstract: A control mechanism for moving at least two components of a gas turbine engine, the control mechanism comprises first and second crankshafts and a torsion bar connected to both crankshafts, each crankshaft is connected to a different component, the crankshafts engage one another via one-way abutment means and the torsion bar is pre-twisted so that up to a predetermined rotational extent the two crankshafts rotate together and beyond that extent only the first crankshaft rotates, thereby one of the two components moves more than the other component.

Abstract: A seal arrangement 30 presents a barrier in the form of a combined seal and anti-fret liner 36 across a shroud ring cavity 32 in order to inhibit air leakage in the platform gap between platforms 33. It will be understood that these gaps are provided for thermal expansion and vibration of vane assemblies but create a leakage path between passage 35 and cavity 32 which can increase aerodynamic losses and therefore reduce engine compressor efficiency. By provision of a combined seal and anti-fret liner 36 such air losses are reduced whilst combining the function of an air leakage seal and an anti-fret liner to prevent abrasive degradation of the mountings 37, 39 and platform section 33 ensures that there is a reduced component count as well as cost, weight and assembly time.