Abstract: Rotary-wing aircraft rotor comprising a rigid hub coupled to the root of each blade in which a trailing return brace comprises a stack of metal plates alternating with plates of visco-elastic material the ends of which being coupled via a ball joint respectively to the root of one blade and to a place of the hub such that the brace is always slightly inclined.

Abstract: The invention relates to a device for damping the vibrations of a rotary-wing aircraft rotor. An annular weight is disposed concentrically of the rotor axis. This weight is supported by at least three resiliently deformable elements such as helical springs, radially biased in directions distributed regularly around the rotor axis. The inner ends of the springs directly bear on a part extending the rotor shaft axially. Their outer ends directly bear on the annular weight so that the spring apply statically balanced centrifugal thrusts to the annular weight. The springs are so still that they support the annular weight without substantially bending.

Abstract: Suspension means for mechanical elements which have a plate rigid with an element which is to be suspended. The rigid plate is connected to fixed mountings by flexible studs working in compression and by a deformable articulated system composed of connecting rods and a floating cross-member, ensuring rotationally rigid connection and providing for absorption of a torque originating from the suspended element, while allowing the element to perform translatory movements.

Abstract: The invention relates to a rotor, specially for a helicopter. This rotor comprises a plurality of blades connected to a rotor hub by flexible, twistable, substantially radial strips, surrounded by tubular rigid sleeves. Rigid rings are secured to the inner ends of the tubular sleeves. Spherical ball and socket joint members are inserted between each radial strip and the rigid ring. The joint members are associated with frequency adaptors for drag movements of the corresponding blade.

Abstract: The invention relates to a device for damping the vibrations of the rotor of a rotary-wing aircraft. This device comprises a flapping weight concentrated near the rotor axis and at least three resiliently deformable elements, such as helical springs. The deformable elements are radially biassed in directions regularly distributed around the rotor axis. The inner ends of the deformable elements directly bear on the flapping weight. Their outer ends directly bear on rigid structure elements, rigidly secured to the rotor hub, so that the biassed deformable elements apply statically balanced centripetal thrusts to the flapping weight.

Abstract: The invention relates to a variable-pitch rotor, specially for a rotary-wing aircraft. Each blade of the rotor is connected to the hub by a flexible connecting member comprising a radial bundle of fibres, each agglomerated by a resin and secured together by a vulcanized elastomer. A rigid tubular sleeve surrounds the connecting member without contact thereto. The outer end of the tubular sleeve is secured to the root part of the blade and its inner end is secured to a rigid ring, to which a blade pitch control lever is externally articulated. Spherical ball and socket joint members are inserted between the rigid ring and rigid parts of the rotor hub. Frequency adaptors are associated with the ball and socket joint members.