Abstract: Rotor blades may be modified with field-installable profiles, or wedges towards the rear trailing end. The wedges may incorporate one or more porous sections to enhance fluid flow through the wedge, and thus reduce trailing edge noise and rotor vibrations when the rotors are in use. The use of porous materials on the trailing end of the blade and/or wedge reduces the intensity of high-frequency noise. A portion of the wedge may retain impermeable characteristics and be paired with a more porous section to minimize the boundary layer, and thus reduce noise. The wedges may be installed in the field, and easy removed, replaced, and/or applied manually to the rotor blade trailing edge. As the vehicle is used, the placement and choice of location and number of wedges applied to one or more rotor blades may be modified each time the vehicle rotor blade come to rest.

Abstract: This invention provides convenient airframe vibration, tracking, and acoustic improvements of a helicopter rotor blade by use of a profile system. The profile system is designed to minimize acoustic disturbances as air passes the airfoil. The profile may be attached through an adhesive system that allows convenient removal and relocation for use by the helicopter manufacturer or by the helicopter operator in a field environment.

Abstract: An opposed conical elastomeric bearing assembly includes a first conical elastomeric bearing with a first inner race and a first outer race, and a second conical elastomeric bearing with a second inner race and a second outer race. Assembling the opposed conical elastomeric bearing assembly may include positioning an outer surface of the second outer race in contact with an inner surface of the first outer race. Assembling the opposed conical elastomeric bearing assembly further includes applying an axial force to urge the first conical elastomeric bearing and the second conical elastomeric bearing together such that a leading edge of the second inner race contacts a shoulder of the first inner race, and, while applying the axial force, deforming a projecting portion of the first inner race such that an outer diameter of the projecting portion is expanded to frictionally engage an inner surface of the second inner race.

Abstract: An opposed conical elastomeric bearing assembly includes a first conical elastomeric bearing with a first inner race and a first outer race, and a second conical elastomeric bearing with a second inner race and a second outer race. Assembling the opposed conical elastomeric bearing assembly may include positioning an outer surface of the second outer race in contact with an inner surface of the first outer race. Assembling the opposed conical elastomeric bearing assembly further includes applying an axial force to urge the first conical elastomeric bearing and the second conical elastomeric bearing together such that a leading edge of the second inner race contacts a shoulder of the first inner race, and, while applying the axial force, deforming a projecting portion of the first inner race such that an outer diameter of the projecting portion is expanded to frictionally engage an inner surface of the second inner race.

Abstract: A rotor arm assembly for use in a rotor craft rotor hub system includes a pitch shaft and a plurality of discrete bearings coupled to the pitch shaft. The plurality of bearings are elastomeric bearings configured to facilitate movement of the rotor arm assembly about a plurality of degrees of freedom. A respective one of the plurality of bearings is configured to accommodate a single degree of freedom.

Abstract: A tooling system may include a cure tool and a biasing element. The cure tool may have a cure tool coefficient of thermal expansion (CTE) and may be configured for curing a composite article formed of two or more components having dissimilar component CTEs. The biasing element may be fixedly attached to the cure tool and has a biasing element CTE that may be different than the cure tool CTE. The biasing element may be configured such that a combination of the cure tool CTE and the biasing element CTE causes a heat-up displacement in the cure tool when heated and the composite article is cured in a distorted shape. When the cured composite article is cooled, the cured composite article may substantially assume an as-designed shape.

Abstract: A rotor arm assembly for use in a rotor craft rotor hub system includes a pitch shaft and a plurality of discrete bearings coupled to the pitch shaft. The plurality of bearings are elastomeric bearings configured to facilitate movement of the rotor arm assembly about a plurality of degrees of freedom. A respective one of the plurality of bearings is configured to accommodate a single degree of freedom.

Abstract: A method of removing a metal detail from a dielectric material of an article may include placing the article in an electrolyte bath such that at least a portion of the metal detail is submerged. The metal detail may be coupled to a dielectric material. The method may further include positioning at least one cathode in the electrolyte bath in spaced relation to the metal detail, and passing electrical current through the metal detail. The method may additionally include deplating the metal detail from the dielectric material in response to passing the electrical current through the metal detail.

Abstract: A tooling system may include a cure tool and a biasing element. The cure tool may have a cure tool coefficient of thermal expansion (CTE) and may be configured for curing a composite article formed of two or more components having dissimilar component CTEs. The biasing element may be fixedly attached to the cure tool and has a biasing element CTE that may be different than the cure tool CTE. The biasing element may be configured such that a combination of the cure tool CTE and the biasing element CTE causes a heat-up displacement in the cure tool when heated and the composite article is cured in a distorted shape. When the cured composite article is cooled, the cured composite article may substantially assume an as-designed shape.

Abstract: A tooling system may include a cure tool and a biasing element. The cure tool may have a cure tool coefficient of thermal expansion (CTE) and may be configured for curing a composite article formed of two or more components having dissimilar component CTEs. The biasing element may be fixedly attached to the cure tool and has a biasing element CTE that may be different than the cure tool CTE. The biasing element may be configured such that a combination of the cure tool CTE and the biasing element CTE causes a heat-up displacement in the cure tool when heated and the composite article is cured in a distorted shape. When the cured composite article is cooled, the cured composite article may substantially assume an as-designed shape.

Abstract: A method of removing a metal detail from a dielectric material of an article may include placing the article in an electrolyte bath such that at least a portion of the metal detail is submerged. The metal detail may be coupled to a dielectric material. The method may further include positioning at least one cathode in the electrolyte bath in spaced relation to the metal detail, and passing electrical current through the metal detail. The method may additionally include deplating the metal detail from the dielectric material in response to passing the electrical current through the metal detail.

Abstract: This invention provides convenient airframe vibration and tracking improvements of a helicopter rotor blade by use of an elastomer profile system that is attached through an adhesive system that allows convenient removal and relocation for use by the helicopter manufacturer or by the helicopter operator in a field environment.

Abstract: This invention provides convenient airframe vibration and tracking improvements of a helicopter rotor blade by use of an elastomer profile system that is attached through an adhesive system that allows convenient removal and relocation for use by the helicopter manufacturer or by the helicopter operator in a field environment.

Abstract: A system of adjustable balancing weights is provided for a helicopter main rotor blade. The trailing edge of the rotor blade is formed with a plurality of recesses that each receive an aerodynamically shaped weight to adjust and balance the weight of the rotor blade. A forward weight recess and a forward weight are also provided on the rotor blade adjacent the rotor blade leading edge. The lateral spacing between the weight adjacent the rotor blade leading edge and the weights adjacent the rotor blade trailing edge provides greater flexibility in balancing the mass of the rotor blade.

Abstract: A trim tab assembly for a helicopter rotor blade includes a plurality of metal panels that are secured to the trailing edge of a composite material helicopter blade. Each of the metal panels can be bent relative to the rotor blade to tune the aerodynamic properties of the rotor blade.

Abstract: The invention provides a weight-reducing bearing assembly for rotary aircraft. An opposed tapered conical elastomeric flap bearing assembly for rotary aircraft includes an outer housing having an outer surface and an inner surface. The outer surface is configured to mechanically connect the bearing assembly to the attachment sections of the hub center body. The inner surface is configured to receive a pair of opposed taper conical bearing elements. An inboard bearing element and an outboard bearing element are located within the outer housing. The bearing elements are arranged in an opposed manner. An axial pre-load can be applied to the opposed bearing assembly wherein the resulting force couple bearing pre-load path is maintained entirely within the bearing assembly. Consequently, the weight of the main rotor hub is reduced increasing the efficiency of rotary flight.

Abstract: The invention provides a weight-reducing bearing assembly for rotary aircraft. An opposed tapered conical elastomeric flap bearing assembly for rotary aircraft includes an outer housing having an outer surface and an inner surface. The outer surface is configured to mechanically connect the bearing assembly to the attachment sections of the hub center body. The inner surface is configured to receive a pair of opposed taper conical bearing elements. An inboard bearing element and an outboard bearing element are located within the outer housing. The bearing elements are arranged in an opposed manner. An axial pre-load can be applied to the opposed bearing assembly wherein the resulting force couple bearing pre-load path is maintained entirely within the bearing assembly. Consequently, the weight of the main rotor hub is reduced increasing the efficiency of rotary flight.