An assembly for a bearing compartment (50A;50B;50C) of a gas turbine engine , the assembly comprising: a first shaft disposed in the gas turbine engine and co-axial with an engine centerline , wherein the first shaft comprises: an end with a radially inward facing surface ; and a first threaded portion disposed on the end of the first shaft ; a bearing stack disposed on a portion of the first shaft ; and a spanner nut disposed on the end of the first shaft and in contact with the bearing stack , wherein the spanner nut comprises: a body ; a piloting hook connected to the body , the piloting hook comprising: a first extension connected to and extending radially inward from the body ; and a second extension connected to and extending in an axial direction from the first extension , wherein the second extension includes a radially outward facing surface ; a second threaded portion configured to engage with the first threaded portion on the end of the first shaft ; and a channel formed by the piloting hook , wherein the channel is configured to receive the end of the first shaft , characterised in that the piloting hook is configured to cause the radially outward facing surface of the second extension to contact a radially inward facing surface of the end of the first shaft . a first shaft disposed in the gas turbine engine and co-axial with an engine centerline , wherein the first shaft comprises: an end with a radially inward facing surface ; and a first threaded portion disposed on the end of the first shaft ; an end with a radially inward facing surface ; and a first threaded portion disposed on the end of the first shaft ; a bearing stack disposed on a portion of the first shaft ; and a spanner nut disposed on the end of the first shaft and in contact with the bearing stack , wherein the spanner nut comprises: a body ; a piloting hook connected to the body , the piloting hook comprising: a first extension connected to and extending radially inward from the body ; and a second extension connected to and extending in an axial direction from the first extension , wherein the second extension includes a radially outward facing surface ; a second threaded portion configured to engage with the first threaded portion on the end of the first shaft ; and a channel formed by the piloting hook , wherein the channel is configured to receive the end of the first shaft , characterised in that the piloting hook is configured to cause the radially outward facing surface of the second extension to contact a radially inward facing surface of the end of the first shaft . a body ; a piloting hook connected to the body , the piloting hook comprising: a first extension connected to and extending radially inward from the body ; and a second extension connected to and extending in an axial direction from the first extension , wherein the second extension includes a radially outward facing surface ; a first extension connected to and extending radially inward from the body ; and a second extension connected to and extending in an axial direction from the first extension , wherein the second extension includes a radially outward facing surface ; a second threaded portion configured to engage with the first threaded portion on the end of the first shaft ; and a channel formed by the piloting hook , wherein the channel is configured to receive the end of the first shaft , characterised in that the piloting hook is configured to cause the radially outward facing surface of the second extension to contact a radially inward facing surface of the end of the first shaft . <EOS>