Abstract: A vibration isolator (20) operative for reducing vibration active on a main rotor (12) of a rotorcraft. The vibration isolator (20) includes a hub attachment fitting (22) secured in combination with the main rotor (12) and a spring-mass system (24) mounting to and rotating with the hub attachment fitting (22). The vibration isolator (20) is characterized by the spring-mass system (24) having a fairing (44) operative to aerodynamically contour the spring-mass system (24) while providing a portion of the working mass thereof. Other features of the vibration isolator include adapting the hub attachment fitting (22) to accept hub-mounted rotor systems (36), provide access to the rotor hub mounting attachment (34), and provide a motion limiting portion (74) for reducing loads acting on the spring-mass system (24).

Abstract: A flexbeam 16 for a bearingless helicoptor rotor includes a composite beam 28, composed of unidirectional fibers bound in an epoxy matrix, having ribs 32, composed of unidirectional fibers bound in a urethane matrix, bonded to each horizontal face at the section of the beam 28 which accommodates lead-lag torsion.

Abstract: A swashplate configuration for helicopter which eliminates the need for scissors linkages through the use of a centering member capable of tilt and axial translation while driving torque to the rotating swashplate member through the use of elastomeric bearing assemblies each consisting of a first stack of flat laminates and a second stack of spherical laminates.