Abstract: A gas turbine engine comprises a fan drive gear system, a low spool connected to the fan drive gear system, and a high spool disposed aft of the low spool. The low spool comprises a rearward-flow low pressure compressor disposed aft of the fan drive gear system, and a forward-flow low pressure turbine disposed aft of the low pressure compressor. The high spool comprises a forward-flow high pressure turbine disposed aft of the low pressure turbine, a combustor disposed aft of the high pressure turbine, and a forward-flow high pressure compressor disposed aft of the combustor.

Abstract: A liner assembly for a fan case includes a noise attenuation layer covered by a face sheet. The face sheet includes openings to the underlying noise attenuation layer. The face sheet and noise attenuation layer include acoustically transparent joints. The noise attenuation layer includes a first side joined to a second side at a seam by an adhesive strip. The adhesive strip bonds the first side to the second side without filling any chambers. The face sheet includes a joint filled with an adhesive providing the desired uninterrupted surface within the fan case. Openings are formed through the joint and the adhesive to communicate with the underlying noise attenuation layer. The joint and seam become essentially transparent acoustically to improve noise attenuation performance.

Abstract: A turbine engine fan casing for containing a separated blade fragment comprising a support case having an axially extending impact zone, a substantially structurally continuous penetrable covering circumscribing the impact zone; and a containment covering circumscribing the penetrable covering. The containment covering comprises a textile fabric containing threads in a warp direction and a fill direction, wherein the threads in the warp direction are of a different denier than the threads in the fill direction.

Abstract: An in situ fan case rub strip machining tool mounts to a LPT/fan rotor shaft assembly of a gas turbine engine. After a fan is removed therefrom such that the machining tool is rotatable about an engine axis of rotation in conjunction with rotation of the LPT/fan rotor shaft assembly. The machining tool permits machining of a rub strip within the fan case of the gas turbine engine without disassembly of the fan case from the core engine as heretofore required. As the machining tool is mounted to the LPT/fan rotor shaft assembly, the cutting tool is accurately locatable relative the engine axis of rotation such that the rub strip is evenly and precisely machined to be concentric with the engine axis to assure proper fan blade tip to rub strip interface.

Abstract: A liner assembly for a fan case includes a noise attenuation layer covered by a face sheet. The face sheet includes openings to the underlying noise attenuation layer. The face sheet and noise attenuation layer include acoustically transparent joints. The noise attenuation layer includes a first side joined to a second side at a seam by an adhesive strip. The adhesive strip bonds the first side to the second side without filling any chambers. The face sheet includes a joint filled with an adhesive providing the desired uninterrupted surface within the fan case. Openings are formed through the joint and the adhesive to communicate with the underlying noise attenuation layer. The joint and seam become essentially transparent acoustically to improve noise attenuation performance.

Abstract: A turbine engine fan casing for containing a separated blade fragment comprising a support case having an axially extending impact zone, a substantially structurally continuous penetrable covering circumscribing the impact zone; and a containment covering circumscribing the penetrable covering. The containment covering comprises a textile fabric containing threads in a warp direction and a fill direction, wherein the threads in the warp direction are of a different denier than the threads in the fill direction.

Abstract: A duct liner assembly includes a noise attenuation layer for absorbing noise energy that is covered by a face sheet. The face sheet includes a seam that is covered by an acoustically active splice. The acoustically active splice includes a plurality of acoustic regions that provide for communication of noise energy to the noise attenuation layer to minimize creation of acoustically dead areas.

Abstract: A fan case assembly includes a noise attenuation layer that is covered by a face sheet. The face sheet includes a first plurality of openings. The noise attenuation layer includes a plurality of individual cells that are in communication with at least one of the first plurality of openings. Noise energy is communicated through the first plurality of openings into the individual cells and dissipated to reduce noise emissions. A seam in the face sheet is covered to protect the underlying noise attenuation layer from damage by a retainer. The retainer is bonded to the face sheet over the seam and includes a second plurality of holes that communicates noise energy through the retainer to the noise attenuation layer. Communication of noise energy through the retainer provides an acoustically active seam that aids in the dissipation of noise energy and thereby reduces the level of sound emitted from the engine.

Abstract: The invention is a penetration resistant turbine engine fan casing (12) for containing separated fragments of a fan blade (16). The casing includes a penetration susceptible support case (14), a penetrable covering (32) circumscribing an impact zone (I) of the support case and an optional, but highly recommended collapsible support covering (34) circumscribing the case but axially offset from the impact zone. A containment covering (36) circumscribes both the penetrable covering (32) and the support covering (34). In a preferred embodiment, the coverings are aromatic polyamide fiber fabrics and the support covering is a collapsible cellular array. In operation, a detached fragment of a fan blade penetrates through the case (14) and the penetrable covering (32), and is plastically deformed by the penetrable covering to reduce the fragment's potential for damaging the containment covering (36).

Abstract: A method of forming a drain assembly 30 for a case 26 is disclosed. Various construction details are developed for minimizing the radial profile and facilitating assembly to an opening in the case while blocking the passage of flames from the exterior to the interior. In one embodiment, the method of forming the drain assembly 30 includes disposing a cover 42 facing one side of the case which has a passage 48 therethrough, disposing a plate 58 having a passage 62 on the other side of the case, and disposing a baffle 66 in the opening to block flames from passing between the cover side of the case and the plate side of the case.

Abstract: A drain assembly 30 for a case 26 is disclosed. Various construction details are developed for minimizing the radial profile and facilitating assembly to an opening in the case while blocking the passage of flames from the exterior to the interior. In one embodiment, the drain assembly 30 has a cover 42 facing one side of the case with passages 48 therethrough, a plate 58 having a passage 62 on the other side of the case, and a baffle 66 disposed in the opening to block flames from passing between the cover side of the case and the plate side of the case.