Lock plate for a bladed rotor arrangement

A turbine arrangement of a gas turbine engine, the turbine arrangement comprising:

• a rotor comprising a disc which incorporates a plurality of circumferentially spaced turbine blades, each blade having an aerofoil extending from a platform and a root portion securing the blade to the disc,
• a lock plate located at an axial end of the root portion of the blade, the lock plate comprising:
• a plate body having an inward facing surface which is located adjacent the blade root and an outward facing surface, radially inner and outer edge portions, and first and second circumferential edges, the inward facing surface and the outward facing surface both extending from the radially inner portion to the radially outer edge portion;
• a head portion located at the radially outer edge portion of the plate body and located within a head portion slot provided at least partially by the turbine blade;
• a foot portion located at the radially inner portion of the plate body and within a foot portion slot provided at least partially by the disc;
• and,
• a projection extending from the outward facing surface away from the turbine blade root in use, the projection being located closer to the foot portion than to the head portion, wherein:
• the centre of gravity of the lock plate is axially spaced from the turbine blade root relative to the geometric centre of the lock plate or a pivot point defined by the head portion such that the lock plate moves away from the turbine blade root when centrifugally loaded.