Patent ID: 6196800
Filing Date: 2001-03-06
Classification: B64C,Y10S

Abstract:
A rotor blade arrangement for a bearingless rotor of a helicopter, comprising a rotor blade, a control sleeve and at least one damping element, wherein:said rotor blade comprises a flexbeam and an airfoil blade;said flexbeam has a flexbeam root end adapted to be connected to a rotor head of the helicopter and a flexbeam head end opposite said flexbeam root end, and includes at least one flexible portion between said flexbeam root and head ends forming a virtual lead-lag hinge that allows flexible bending of said flexbeam in a lead-lag plane about said lead-lag hinge;said airfoil blade has a blade root connected to said flexbeam head end and an airfoil portion extending from said blade root along a blade lengthwise axis in an outboard direction away from said flexbeam root end;said control sleeve extends along and surrounds at least a majority of said flexbeam, with said majority of said flexbeam located in a substantially enclosed space within said control sleeve;said at least one damping element is arranged and adapted to damp lead-lag oscillations of said rotor blade involving flexible bending of said flexbeam in said lead-lag plane about said lead-lag hinge; andsaid at least one damping element is connected to said control sleeve and is connected to said rotor blade at a first location displaced outboard from said lead-lag hinge in said outboard direction away from said flexbeam root end.