 A hangar and flight deck was added aft to allow a Westland Wasp helicopter to be operated, at the expense of one of the Limbo anti-submarine mortars, while a Seacat launcher and the associated GWS20 director was mounted on the hangar roof.Two 20-mm cannons were added either side of the ship's bridge.A MRS3 fire control system replaced the Mark 6M, and its integral Type 903 radar allowed the Type 277 height finder radar to be removed.