Abstract: An acoustic panel for attenuating sound and a method of making the acoustic panel. A septum structure is created comprising a layer of chopped fibers between layers of uncured epoxy. The structure is forced onto the open ends of the cells so that the edges of the cell walls cut the structure into pieces, with each piece having the same cross-sectional size and shape as one of the cells, and the pieces are pushed further into the cells to a specific position. The epoxy layers are cured, and holes are created in the cured epoxy layers to expose the chopped fibers and create septum layers within the cells. The chopped fibers may be sufficiently long and/or strong to provide structural support across each cell but sufficiently short and/or weak to be cut by the edge of the cell wall, and may melt at a higher temperature than the epoxy cures.

Abstract: An aircraft nacelle and method of fabricating a monolithic lipskin of the nacelle. The nacelle may include a fan cowl, a bulkhead, and the monolithic lipskin. The lipskin may be formed by spin-forming or explosive forming an annularly-shaped plate onto a mandrel, and machining or chemically-milling integrated stiffeners or other protrusions and attachment tabs into an inner mold line (IML) of the lipskin. The machining or chemical milling may occur before or after the spin-forming or explosive forming. The stiffeners may have a spiral or circumferential configuration. An attachment tab extending from the IML may attach to the bulkhead, such that an outer mold like (OML) of the lip-skin is not disrupted by mechanical fasteners attaching the lipskin to the bulkhead.

Abstract: An acoustic panel for attenuating sound and a method of making the acoustic panel. A septum structure is created comprising a layer of chopped fibers between layers of uncured epoxy. The structure is forced onto the open ends of the cells so that the edges of the cell walls cut the structure into pieces, with each piece having the same cross-sectional size and shape as one of the cells, and the pieces are pushed further into the cells to a specific position. The epoxy layers are cured, and holes are created in the cured epoxy layers to expose the chopped fibers and create septum layers within the cells. The chopped fibers may be sufficiently long and/or strong to provide structural support across each cell but sufficiently short and/or weak to be cut by the edge of the cell wall, and may melt at a higher temperature than the epoxy cures.

Abstract: An aircraft nacelle and method of fabricating a monolithic lipskin of the nacelle. The nacelle may include a fan cowl, a bulkhead, and the monolithic lipskin. The lipskin may be formed by spin-forming or explosive forming an annularly-shaped plate onto a mandrel, and machining or chemically-milling integrated stiffeners or other protrusions and attachment tabs into an inner mold line (IML) of the lipskin. The machining or chemical milling may occur before or after the spin-forming or explosive forming. The stiffeners may have a spiral or circumferential configuration. An attachment tab extending from the IML may attach to the bulkhead, such that an outer mold like (OML) of the lip-skin is not disrupted by mechanical fasteners attaching the lipskin to the bulkhead.

Abstract: An inflatable compaction tool for consolidating a composite material inside a faceted hollow or tubular mold for a composite part is made from an elastic material. The compaction tool includes relatively flat wall segments conjoined by corner segments that define a sealed chamber. The wall segments curve away from the mold surface toward the midpoint of each wall segment, so that as a pressurized fluid is introduced into the compaction tool, a component of the force exerted on the tool interior surface is transmitted through the wall segments toward the corner segments. Thus, during initial inflation, the corner segments are forced toward the corner regions of the mold before the wall segments contact the composite material, firmly compressing the composite material into the corner regions of the mold before the friction of the wall segments against the composite material inhibits expansion of the corner segments into the mold corner regions.

Abstract: An inflatable compaction tool for consolidating a composite material inside a faceted hollow or tubular mold for a composite part is made from an elastic material. The compaction tool includes relatively flat wall segments conjoined by corner segments that define a sealed chamber. The wall segments curve away from the mold surface toward the midpoint of each wall segment, so that as a pressurized fluid is introduced into the compaction tool, a component of the force exerted on the tool interior surface is transmitted through the wall segments toward the corner segments. Thus, during initial inflation, the corner segments are forced toward the corner regions of the mold before the wall segments contact the composite material, firmly compressing the composite material into the corner regions of the mold before the friction of the wall segments against the composite material inhibits expansion of the corner segments into the mold corner regions.

Abstract: An inflatable compaction tool for consolidating a composite material inside a faceted hollow or tubular mold for a composite part is made from an elastic material. The compaction tool includes relatively flat wall segments conjoined by corner segments that define a sealed chamber. The wall segments curve away from the mold surface toward the midpoint of each wall segment, so that as a pressurized fluid is introduced into the compaction tool, a component of the force exerted on the tool interior surface is transmitted through the wall segments toward the corner segments. Thus, during initial inflation, the corner segments are forced toward the corner regions of the mold before the wall segments contact the composite material, firmly compressing the composite material into the corner regions of the mold before the friction of the wall segments against the composite material inhibits expansion of the corner segments into the mold corner regions.

Abstract: A method of forming acoustic holes in a composite sound-insulating material includes creating a image of at least a portion of an array of holes and transferring the image to an ultraviolet (UV) radiation transparent medium. The method continues with positioning the medium in contact with a UV-curable mask and exposing the medium-covered mask to UV radiation to cure the UV-exposed areas. The method further includes removing the uncured mask material to create an abrading mask that includes a plurality of holes in a desired pattern. The method also includes positioning the abrading mask in contact with the sound-insulating material and directing a stream of abrasive matter at the abrading mask to create perforations in the sound-insulating material that correspond to the pattern of holes in the abrading mask.

Abstract: An inflatable compaction tool for consolidating a composite material inside a faceted hollow or tubular mold for a composite part is made from an elastic material. The compaction tool includes relatively flat wall segments conjoined by corner segments that define a sealed chamber. The wall segments curve away from the mold surface toward the midpoint of each wall segment, so that as a pressurized fluid is introduced into the compaction tool, a component of the force exerted on the tool interior surface is transmitted through the wall segments toward the corner segments. Thus, during initial inflation, the corner segments are forced toward the corner regions of the mold before the wall segments contact the composite material, firmly compressing the composite material into the corner regions of the mold before the friction of the wall segments against the composite material inhibits expansion of the corner segments into the mold corner regions.

Abstract: A computer-based facility configured for programming of numerically controlled (NC) machines includes an NC data set generator component used in allowing a user to select data sets for NC programs that control the NC machines. For example, such data sets may include features, processes, tools, and functions combined in accordance with predetermined practices, such as best practices. Aspects of the facility allow for integration of generated data sets into a computer aided drafting/computer aided manufacturing (CAD/CAM) environment, such as CATIA.

Abstract: An apparatus and method for forming a friction stir weld joint in a workpiece are provided. The apparatus includes a friction stir welding tool having a shoulder and a rotatable pin extending therefrom. The rotational speed of the pin can be adjusted during a friction stir welding operation, e.g., cyclically and/or according to a predetermined schedule, so that the pin mixes the plasticized material of the workpiece. The workpiece can also be preheated before friction stir welding.

Abstract: A hard machining process uses a cylindrical tool (21) of ceramic or other hard machining material of comparatively low cost that provides a circular cutting edge to be engaged in cutting relation with hardened workpiece (20) to be machined. As tool cutting edge wear occurs, the tool (21) is rotated through a small angle to bring into contact with the workpiece (20) a fresh portion of the cutting edge. It is not necessary to rotate that tool (21) sufficiently to effect replacement of the entire cutting edge portion in engagement with the tool. Sufficient angular movement of the tool is made to replace that of the cutting edge that has the greatest effect on the finish of the machined workpiece (20), which is the cutting location where the removed chip is thinnest.

Abstract: An apparatus and method for forming a friction stir weld joint in a workpiece are provided. The apparatus includes a friction stir welding tool having a shoulder and a rotatable pin extending therefrom. The rotational speed of the pin can be adjusted during a friction stir welding operation, e.g., cyclically and/or according to a predetermined schedule, so that the pin mixes the plasticized material of the workpiece. The workpiece can also be preheated before friction stir welding.