An elastomeric bearing assembly has a centrifugal force bearing axially captured relative to a sliding interface. The sliding interface has one or more low friction regions and one or more high friction regions. One or more piezo actuators are configured to force one or more corresponding high friction regions against the centrifugal force bearing when actuated. The sliding interface may have a circular shape, wherein the one or more low friction regions and the one or more high friction regions are alternating concentric segments of the sliding interface. The one or more high friction regions are recessed on the sliding interface relative to the one or more low friction regions.

A lead-lag damper arranged inside a blade of a rotor of a rotary wing aircraft. The lead-lag damper comprises an inner strength member provided with a cage in which a ball-joint connection is arranged, an outer strength member for securing to the blade, and an elastomer material member arranged between the two strength members. The two strength members and the elastomer material member extending beyond the zone around the cage so that the relative movements between two strength members resulting from the movements of the blade are damped by deformations of the elastomer material member, at least a portion of the lead-lag damper being designed to occupy a portion of the inside of the blade that is conventionally filled with foam.

A lead-lag damper arranged inside a blade of a rotor of a rotary wing aircraft. The lead-lag damper comprises an inner strength member provided with a cage in which a ball-joint connection is arranged, an outer strength member for securing to the blade, and an elastomer material member arranged between the two strength members. The two strength members and the elastomer material member extending beyond the zone around the cage so that the relative movements between two strength members resulting from the movements of the blade are damped by deformations of the elastomer material member, at least a portion of the lead-lag damper being designed to occupy a portion of the inside of the blade that is conventionally filled with foam.

Embodiments are directed to a double Hooke's joint gimbal in a rotor system. An upper Hooke's joint has four arms extending radially outward to define first and second axes, and a lower Hooke's joint has four arms extending radially outward to define third and fourth axes. A pair of connectors couple the upper Hooke's joint and the lower Hooke's joint. A first set of bearings are positioned between arms on the upper and lower Hooke's joints and the connectors. The first set of bearings comprise an elastomer, such as elastomeric journal bearings. The upper Hooke's joint is coupled to a yoke and rotor blades by a driver assembly that allows rotor blade flapping. The lower Hooke's joint is coupled to and driven by a mast. A spherical bearing allows the upper Hooke's joint to move laterally along the mast.

Embodiments are directed to a double Hooke's joint gimbal in a rotor system. An upper Hooke's joint has four arms extending radially outward to define first and second axes, and a lower Hooke's joint has four arms extending radially outward to define third and fourth axes. A pair of connectors couple the upper Hooke's joint and the lower Hooke's joint. A first set of bearings are positioned between arms on the upper and lower Hooke's joints and the connectors. The first set of bearings comprise an elastomer, such as elastomeric journal bearings. The upper Hooke's joint is coupled to a yoke and rotor blades by a driver assembly that allows rotor blade flapping. The lower Hooke's joint is coupled to and driven by a mast. A spherical bearing allows the upper Hooke's joint to move laterally along the mast.

A flexbeam rotor blade assembly includes a flexbeam having a body that includes a first surface, a second, opposing surface, and an opening extending through the first and second surfaces. At least one snubber is mounted to one of the first and second surfaces spaced along the body from the opening. A snubber retainer is mounted to one of the first and second surfaces between the body and the at least one snubber. The snubber retainer includes a retainer plate having a snubber attachment member to which the snubber assembly is mounted and a mounting arm including a retainer plate opening spaced from the snubber attachment member. The retainer plate opening registers with the opening in the flexbeam. A mechanical fastener extends through the retainer plate opening and the opening in the flexbeam. The mechanical fastener joins the snubber retainer to the one of the first and second surfaces.

A flexbeam rotor blade assembly includes a flexbeam having a body that includes a first surface, a second, opposing surface, and an opening extending through the first and second surfaces. At least one snubber is mounted to one of the first and second surfaces spaced along the body from the opening. A snubber retainer is mounted to one of the first and second surfaces between the body and the at least one snubber. The snubber retainer includes a retainer plate having a snubber attachment member to which the snubber assembly is mounted and a mounting arm including a retainer plate opening spaced from the snubber attachment member. The retainer plate opening registers with the opening in the flexbeam. A mechanical fastener extends through the retainer plate opening and the opening in the flexbeam. The mechanical fastener joins the snubber retainer to the one of the first and second surfaces.

A bearing assembly is for movably coupling a first member having a centerline and displaceable about a rotation axis perpendicular to the centerline and a second member displaceable about the centerline and/or another axis perpendicular to the centerline. The bearing assembly includes a laminated bearing having an inner axial end coupled with the second member and an outer axial end spaced from the inner end along the first member centerline and coupleable with the first member. A clutch mechanism releasably couples the bearing outer axial end with the first member when the first member angularly displaces about the rotation axis. The clutch mechanism preferably has a first portion connected with the bearing outer axial end, a second portion coupled with the first member and engageable with the first portion to couple the two members, and a biasing member spaces apart the two clutch portions when the first member is non-rotational.

Embodiments are directed to a rotor hub assembly comprising a yoke configured to attach rotor blades thereto, a single Hooke's joint configured to attach to, and transmit forces between, a mast and the yoke, and a spherical bearing coupled between the yoke and the mast. Two pillow blocks couple the single Hooke's joint to the yoke. An adapter sleeve is attached to the pillow blocks and is positioned to surround the spherical bearing. The adapter sleeve extends between the single Hooke's joint and the mast. A hub lock extension is attached to the yoke. The hub lock extension is configured to receive a hub lock that prevents gimballing of the yoke when engaged.

Embodiments are directed to a rotor hub assembly comprising a yoke configured to attach rotor blades thereto, a single Hooke's joint configured to attach to, and transmit forces between, a mast and the yoke, and a spherical bearing coupled between the yoke and the mast. Two pillow blocks couple the single Hooke's joint to the yoke. An adapter sleeve is attached to the pillow blocks and is positioned to surround the spherical bearing. The adapter sleeve extends between the single Hooke's joint and the mast. A hub lock extension is attached to the yoke. The hub lock extension is configured to receive a hub lock that prevents gimballing of the yoke when engaged.