Patent ID: 10641321

Abstract:
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.