A hybrid bearing system includes a self-lubricated bearing assembly including a self-lubricated bearing element and at least one elastomeric bearing assembly arranged adjacent the self-lubricated bearing assembly. The elastomeric bearing assembly is torsionally mated with the self-lubricated bearing element as a torsional load is applied about an axis of the self-lubricated bearing.

An electric propulsion system includes a static mast fixed to the airframe and a secondary mast positioned in overlapping arrangement with the static mast. The secondary mast defines an axis of rotation. An elastomeric bearing is arranged at an interface between the static mast and the secondary mast. An actuator assembly includes at least one actuator connected to the secondary mast. The actuator assembly is operable to pivot the secondary mast relative to the axis of rotation.

An electric propulsion system includes a static mast fixed to the airframe and a secondary mast positioned in overlapping arrangement with the static mast. The secondary mast defines an axis of rotation. An elastomeric bearing is arranged at an interface between the static mast and the secondary mast. An actuator assembly includes at least one actuator connected to the secondary mast. The actuator assembly is operable to pivot the secondary mast relative to the axis of rotation.

A rotary wing aircraft bearing that provides a constrained relative motion between a first rotary wing aircraft member and a second rotary wing aircraft member. The bearing includes an elastomeric mold bonded laminated bearing stack, the elastomeric mold bonded laminated bearing stack including a plurality of mold bonded alternating layers of nonelastomeric shim member layers and elastomeric shim members layers, the alternating layers having an exterior surface and an interior center distal from the exterior surface. At least one of the elastomeric shim members layers has an interior elastomer region distal from the exterior surface, the interior elastomer region formed an interior cured elastomer composition having at least a first interior optical characteristic ingredient, and an exterior elastomer region encompassing the interior elastomer region, the exterior elastomer region proximate the exterior surface, the exterior elastomer region formed from an exterior cured elastomer composition having at least a second exterior optical characteristic ingredient, the at least second exterior optical characteristic ingredient different than the interior cured elastomer composition first interior optical characteristic ingredient, wherein with an elastomer void crack propagating from the exterior surface inward towards the interior elastomer region and a repeated rotary wing aircraft relative motion between the first rotary wing aircraft member and the second rotary wing aircraft member generates a plurality of interior cured elastomer composition crumbs to be expelled from the elastomer void, the interior cured elastomer composition crumbs optically distinguishable from the exterior cured elastomer composition.

A rotary wing aircraft bearing that provides a constrained relative motion between a first rotary wing aircraft member and a second rotary wing aircraft member. The bearing includes an elastomeric mold bonded laminated bearing stack, the elastomeric mold bonded laminated bearing stack including a plurality of mold bonded alternating layers of nonelastomeric shim member layers and elastomeric shim members layers, the alternating layers having an exterior surface and an interior center distal from the exterior surface. At least one of the elastomeric shim members layers has an interior elastomer region distal from the exterior surface, the interior elastomer region formed an interior cured elastomer composition having at least a first interior optical characteristic ingredient, and an exterior elastomer region encompassing the interior elastomer region, the exterior elastomer region proximate the exterior surface, the exterior elastomer region formed from an exterior cured elastomer composition having at least a second exterior optical characteristic ingredient, the at least second exterior optical characteristic ingredient different than the interior cured elastomer composition first interior optical characteristic ingredient, wherein with an elastomer void crack propagating from the exterior surface inward towards the interior elastomer region and a repeated rotary wing aircraft relative motion between the first rotary wing aircraft member and the second rotary wing aircraft member generates a plurality of interior cured elastomer composition crumbs to be expelled from the elastomer void, the interior cured elastomer composition crumbs optically distinguishable from the exterior cured elastomer composition.

An elastomeric bearing includes a first race having an axis of rotation, a second race coaxially arranged relative to the first race and spaced from the first race by a gap and a bearing body in the gap connecting the first race to the second race. The bearing body is formed from a first plurality of elastomeric laminae coaxial with the first race and a second plurality of carbon fiber laminae coaxial with the first race, and the elastomeric laminae and the carbon fiber laminae alternate in a direction from the first race to the second race. The carbon fiber laminae may each include multiple sheets of carbon fibers embedded in a thermoplastic such as polyether ether ketone (PEEK).

An elastomeric bearing includes a first race having an axis of rotation, a second race coaxially arranged relative to the first race and spaced from the first race by a gap, a bearing body in the gap connecting the first race to the second race, the bearing body comprising a plurality of first laminae coaxial with the first race and a plurality of second laminae coaxial with the first race, the first laminae being formed from a different material than the second laminae, and a metal end cap connected to the first race or to the second race. The metal end cap includes an at least partially hollow interior and/or is formed by an additive manufacturing process.

A bearing assembly is for movably coupling first and second members, one being movable relative to the other. A plain bearing section includes an inner ring connectable with the first member and an outer convex bearing surface. An outer ring is disposed about the inner ring and has an inner concave bearing surface disposed against the inner ring bearing surface. The two bearing surfaces are formed such that one bearing surfaces slides against the other when the movable member displaces about a first axis and two bearing surfaces engage to prevent displacement between the two rings when the movable member displaces about a second axis. An elastomeric bearing section is disposed about the plain bearing section, is connected with the second member and formed such that at least a portion of the elastomeric bearing section flexes when the movable member angularly displaces about the second axis.

A bearing assembly is for movably coupling first and second members, one being movable relative to the other. A plain bearing section includes an inner ring connectable with the first member and an outer convex bearing surface. An outer ring is disposed about the inner ring and has an inner concave bearing surface disposed against the inner ring bearing surface. The two bearing surfaces are formed such that one bearing surfaces slides against the other when the movable member displaces about a first axis and two bearing surfaces engage to prevent displacement between the two rings when the movable member displaces about a second axis. An elastomeric bearing section is disposed about the plain bearing section, is connected with the second member and formed such that at least a portion of the elastomeric bearing section flexes when the movable member angularly displaces about the second axis.

In one embodiment, a rotor hub comprises a hub body, and a plurality of blade grips configured for attaching a plurality of rotor blades. The rotor hub further comprises a plurality of centrifugal force bearings coupled to the plurality of blade grips, wherein a focus of the plurality of centrifugal force bearings is aligned with a centerline of a rotor mast. The rotor hub further comprises a plurality of drive links configured to transfer torque to the plurality of rotor blades, wherein the plurality of drive links is positioned to correspond with a leading edge side of the plurality of rotor blades. The rotor hub further comprises a plurality of pitch horns configured to adjust a pitch of the plurality of rotor blades.