Patent ID: 7229252

Claim:
A locking assembly for a rotor stage of a gas turbine engine, said rotor stage comprising an annular array of radially extending blades secured to a rotor disc via an attachment and an annular retaining plate capable of preventing axial movement of the blades, said retaining plate being secured to an axial face of the disc via a bayonet arrangement, said bayonet arrangement comprising engagable and complimentary castellations on the disc and lands on the retaining plate, characterised in that the locking assembly comprises a locking plug having an arm and a leg part and when assembled said arm engages upstream of a radially inner region of the retaining plate and said leg part being configured to span between and abut both circumferentially adjacent castellations and lands, thereby preventing relative rotation between the disc and the retaining plate wherein said locking plug is configured in a generally Y-shaped cross section having a channel portion defined by arms and said leg part and when assembled said arms engage upstream and downstream of a radially inner region of the retaining plate wherein the assembly comprises a securing plate, the securing plate spanning between circumferentially adiacent castellations thereby preventing the locking plug from disengaging the disc and retaining plate.