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

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: 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: 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.