Abstract: An auxiliary helicopter rotor on which at least two blades extend radially from a hub, each of which blades presents a root connecting it to the hub, and a beam having two wings extending respectively along the back and face of the blade; the wings of the beam diverging along the root in such a manner as to form a fork engaged both by a center plate on the hub, to which the fork is connected via a spherical joint, and by a flexible leaf extending from the center plate inside the fork and connected to the beam of the blade by means of an axial joint.

Abstract: A helicopter rotor on which each blade is connected in articulated manner to a center hub by means of a fork, the vertical plane movement of which is limited, below a given speed of the rotor, by a pair of limit rocker arms located between the hub and a ring nut mounted for rotation on the fork and angularly integral with the hub by means of a rod of variable length connected in articulated manner to a slide supported on the hub and arranged substantially horizontally and crosswise in relation to the blade.

Abstract: A main helicopter rotor on which a rotary tubular shaft supports, at its top end, an annular hub integral with the tubular shaft itself. The assembly consisting of the tubular shaft and the hub is closed off at the top by a bell connected in removable manner to the hub and enclosing an oscillating plate assembly supported on a fixed shaft extending inside the aforementioned tubular shaft. A rotary ring on the oscillating plate assembly is connected to blade pitch change levers via respective rocker arms connected in articulated manner to the aforementioned rotary ring via respective pins extending radially in relation to the aforementioned bell and accessible via respective radial holes formed through the same.

Abstract: There is disclosed a longitudinal member for a helicopter blade made by placing inside an open mold an open outer covering on which covering and in contact with are arranged a number of uncured axial straps which define top and bottom backs of the longitudinal member itself; the straps being compacted, prior to closure of the mold, against a center core and a front nose by inserting a rear element made of prehardened synthetic composite material, the rear element having an essentially C-shaped section and the opposite side edges of the outer covering being folded thereover prior to closure of the mold.

Abstract: Helicopter rotor on which a number of blades are each connected to a perimetrical bridge element on a hub by means of a fork element extending round the said bridge element and connected to it by means of two elastomer supports, arranged in series, of which one is designed to dampen at least operation of the blade in the hub plane.

Abstract: Helicopter rotor on which the blades are each connected to a center hub plate by means of a U-shaped fork connected to the hub by an elastomer support, the latter supporting a static supporting device for limiting dynamic oscillation on the relative blade in the vertical plane, the said device providing for use of a pin faceted on the side, mounted so as to turn on a taper seat integral with the relative fork and designed to engage with a mating surface integral with the hub.

Abstract: Helicopter rotor on which static balancing of the rotor is provided for by a number of annular-shaped counterweights housed inside each pin securing each blade to the hub; the said counterweights being supported by a rod pressed an clicked inside an axial hole on the relative pin.

Abstract: A device for controlling the cyclic and collective pitch of a helicopter rotor in which a fixed ring of an oscillating plate is maintained regularly fixed and is guided in its oscillations with respect to a drive shaft by a plurality of variable configuration supports uniformly distributed about the said drive shaft and connected to the said fixed ring by means of cylindrical pivots at least one of which is eccentric with respect to an axis rotation of an associated supported fork, which is perpendicular thereto.

Abstract: A countertorque rotor for helicopters in which a transmission shaft keyed transversely onto a drive shaft and disposed obliquely within a hub has each of its ends coupled in a slidable manner within an inner bush of an associated elastomeric coupling this latter carrying screw actuator means which can act axially on the said shaft to displace the said hub with respect to the shaft (3) itself in the direction of the axis of this latter.

Abstract: A composite hub for a helicopter rotor, the hub having the form of a flat plate of laminated structure provided with a plurality of through holes each able to house an elastomeric coupling for connection of an associated blade, and a central layer of the said plate being constituted by a force distributor element in contact with each surface of which there is disposed at least one layer constituted by radial elements extending outwardly of an axis of rotation of the hub and an annular element disposed in contact with the free ends of the said radial elements; these latter being connected to the radial elements disposed on the other side of the distributor element by means of axial elements (25) defining part of the surface of the said aperture.

Abstract: A method for making helicopter blade spars in which a tape of reinforced resin is laid up with a continuous circulatory movement along an annular path defined by a lateral surface of a former of a forming mould in such a way as to define an annular body constituted by two ribs of the spar, rigidly connected together and opposite one another; each rib being subsequently separated from the other by cutting the said annular body.

Abstract: The multi-blade articulated rotor for helicopters, comprises a hub connected to a shaft rotatable substantially about a vertical axis, the hub being in the form of a plate comprising a plurality of perforations, each of which defines a bridge of material of said plate between a part of the edge of said perforation and a part of the edge of said plate; a plurality of yokes, each of which is substantially of U shape and comprises a pair of substantially parallel arms and a base element which connects together one end of said arms, the other end of the arms being connected to one of said blades, said base element being inserted into one of said perforations in the hub; a plurality of elastomer bearings, each of which is disposed between said base element of a yoke and the corresponding hub bridge; and means for limiting the amplitude of the swivel movement which each of said yokes can make substantially in a vertical plane.