Abstract: A bolt which extends into the first casing part, into the hole in the barrel nut, and into the second casing part, wherein the bolt engages with the barrel nut so as to join the first casing part to the second casing part; wherein the barrel nut includes a first portion and a second portion, wherein the first portion of the barrel nut is structurally weaker than the second portion of the barrel nut such that, if a predetermined load between the first casing part and the second casing part is exceeded, the first portion of the barrel nut becomes crushed while the second portion of the barrel nut remains engaged with the bolt. The casing assembly may be included in a gas turbine engine.

Abstract: A rotor assembly includes a rotor disc and a plurality of circumferentially-spaced, radially outwardly extending rotor blades. The rotor disc has a rim and a plurality of circumferentially spaced slots provided in the rim of the rotor disc, each rotor blade having a root, the root of each rotor blade being arranged in a corresponding one of the slots in the rim of the rotor disc, and at least one of the slots having a chocking device accommodated within a space between a radially outer surface of the slot and a radially inner surface of the root of the rotor blade. The chocking device includes at least a first spring and a second spring, the first and second springs each abutting a radially inner surface of the root of the corresponding rotor blade and arranged transversely relative to a longitudinal axis of the slot.

Abstract: A bolt which extends into the first casing part, into the hole in the barrel nut, and into the second casing part, wherein the bolt engages with the barrel nut so as to join the first casing part to the second casing part; wherein the barrel nut includes a first portion and a second portion, wherein the first portion of the barrel nut is structurally weaker than the second portion of the barrel nut such that, if a predetermined load between the first casing part and the second casing part is exceeded, the first portion of the barrel nut becomes crushed whilst the second portion of the barrel nut remains engaged with the bolt. The casing assembly may be included in a gas turbine engine.

Abstract: A gas turbine engine casing assembly has a first casing element which is located radially outward of one or more rotating aerofoil elements of the gas turbine engine. The first casing element is radially enclosed by a track element, a septum layer, a second casing element and a fan case. The track element is formed from an abrasion resistant material in order to prevent abrasion of the septum layer during excoriation of the first casing element.

Abstract: A method for forming a pressure measurement hole in a component includes the step of forming a hole in a body of the component, the hole extending from a body surface of the component. An insert having a longitudinal passage is fitted into the hole such that the insert protrudes from the body surface. The protruding end of the insert is machined to define an insert surface profile matched to the body surface profile and displaced from the body surface by a distance substantially equal to a thickness of a covering layer that is to be bonded onto the body surface. A blocking pin is inserted into the insert passage. The covering layer is then bonded to the body surface in the region of the hole and insert after which the blocking pin is removed from the insert to open the pressure measurement hole.

Abstract: A rotor assembly includes a rotor disc and a plurality of circumferentially-spaced, radially outwardly extending rotor blades. The rotor disc has a rim and a plurality of circumferentially spaced slots provided in the rim of the rotor disc, each rotor blade having a root, the root of each rotor blade being arranged in a corresponding one of the slots in the rim of the rotor disc, and at least one of the slots having a chocking device accommodated within a space between a radially outer surface of the slot and a radially inner surface of the root of the rotor blade. The chocking device includes at least a first spring and a second spring, the first and second springs each abutting a radially inner surface of the root of the corresponding rotor blade and arranged transversely relative to a longitudinal axis of the slot.

Abstract: An annulus filler is provided for mounting to a rotor disc of a gas turbine engine and for bridging the gap between two adjacent blades attached to the rotor disc. The annulus filler defines an airflow surface for air being drawn through the engine. The annulus filler has one or more primary connectors for connecting the annulus filler to the rotor disc, and for resisting, in use, centrifugal forces on the annulus filler. Each primary connector allows rotation of the annulus filler around the center line of the engine relative to the rotor disc at that primary connector. The annulus filler also has a secondary connector for connecting the annulus filler to the rotor disc and for resisting, in use, motion of the annulus filler relative to the rotor disc in a first axial direction. The secondary connector allows rotation of the annulus filler around the center line of the engine relative to the rotor disc at the secondary connector.

Abstract: A method for forming a pressure measurement hole in a component includes the step of forming a hole in a body of the component, the hole extending from a body surface of the component. An insert having a longitudinal passage is fitted into the hole such that the insert protrudes from the body surface. The protruding end of the insert is machined to define an insert surface profile matched to the body surface profile and displaced from the body surface by a distance substantially equal to a thickness of a covering layer that is to be bonded onto the body surface. A blocking pin is inserted into the insert passage. The covering layer is then bonded to the body surface in the region of the hole and insert after which the blocking pin is removed from the insert to open the pressure measurement hole.

Abstract: An annulus filler is provided for mounting to a rotor disc of a gas turbine engine and for bridging the gap between two adjacent blades attached to the rotor disc. The annulus filler defines an airflow surface for air being drawn through the engine. The annulus filler has one or more primary connectors for connecting the annulus filler to the rotor disc, and for resisting, in use, centrifugal forces on the annulus filler. Each primary connector allows rotation of the annulus filler around the centre line of the engine relative to the rotor disc at that primary connector. The annulus filler also has a secondary connector for connecting the annulus filler to the rotor disc and for resisting, in use, motion of the annulus filler relative to the rotor disc in a first axial direction. The secondary connector allows rotation of the annulus filler around the centre line of the engine relative to the rotor disc at the secondary connector.