The present invention relates to a wind turbine rotor balancing method which compensates imbalances between the centers of gravity of the wind turbine blades, in both magnitude and position along said blades, so that the amount of mass needed to carry out this balancing method is minimized, while reducing the loads and vibrations associated with a position of the center of gravity of the rotor not aligned with the axis of rotation thereof, wherein the invention further relates to the wind turbine rotor balancing system and the wind turbine balanced with the above method.

A rotorcraft including a rotor hub, a pitch housing moveable relative to the rotor hub about at least a feather axis and a flap axis, the pitch housing defining an internal volume, a bearing pin, the inboard end portion of the bearing pin being fixedly connected to the rotor hub, wherein the bearing pin defines the feather axis, a spherical bearing connected to the inboard end portion of the pitch housing and defining the flap axis, wherein the bearing pin extends through the spherical bearing, a rotor blade connected to the outboard end portion of the pitch housing, and a sensor assembly positioned in the internal volume and operatively connected to both the pitch housing and the outboard end portion of the bearing pin.

A multirotor aircraft that includes a chassis, at least three engines that equipped with propellers, and a free wing that is axially connected to the chassis. The attack angle of the free wing is changed relatively to the chassis due to flow of air. When the aircraft is hovering then the free wing is free to rotate, when wind flows over the wing during hovering then the tilt angle of the wing is changed by forces of the wind to a position in which a drag force on the wing is reduced, and by that enables a precise hovering relative to a ground point and precise control over the aircraft. The free wing provides lift force in horizontal flight and in situations of front horizontal wind during hovering and by that reducing the amount of energy required to operate the aircraft.

A rotor for a hover-capable aircraft is described that comprises: a drive mast; a hub operatively connected to the drive mast and rotatable about a first axis; and at least two blades hinged to the hub, via a rigid or elastically deformable connection, so as to be able to assume an attitude rotated about and/or translated along at least a second axis with respect to said hub; the aircraft further comprising sensor means configured to detect the attitude of at least one said blade with respect to the hub; the sensor means are configured to acquire an optical image associated with the attitude of the blade with respect to the hub.

An inertia weight assembly positionable within a receiving portion of a rotor blade for use on a rotorcraft. The inertia weight assembly includes a weighted core and a casing having a closed outboard end and forming a cavity. The weighted core is disposed in the cavity such that the casing at least partially encloses the weighted core. The weighted core is formed from a first material and the casing is formed from a second material that is dissimilar to the first material. The casing provides an interface between the weighted core and the receiving portion of the rotor blade. The second material is more bondable to the receiving portion of the rotor blade than the first material.

A system and method for measuring, or otherwise determining pitch length adjustments to a pitch link coupled to a rotor blade in a rotorcraft includes vertical track adjustment indicators machined onto an exterior of the tube of the pitch link and a vertical reference indicator machined onto an exterior of the upper or the lower rod of the pitch link. A metric of a pitch length adjustment can be determined by tracking or counting how many track adjustment indicators pass the reference indicator while the tube of the pitch link is being turned in either direction for increasing or decreasing the pitch length. The track adjustment indicators can be relied upon to track one or a series of adjustments for tracking a rotor blade installed in a rotor assembly.

A plurality of rotary blades of a flight vehicle of the present invention includes a first rotary blade provided on one side of the main body in a width direction and a second rotary blade provided on the other side of the main body in the width direction. An acquisition unit acquires rotational positions of the rotary blades. A control unit controls the rotational positions based on the rotational positions acquired so that the rotational positions of the first rotary blade and the second rotary blade associated with each other are in a predetermined positional relationship.

A device for determining a state of a rotor of a rotorcraft. The rotorcraft comprises a fuselage and a main rotor provided with a hub rotating about a mast of the rotor and with a plurality of blades whose second ends describe a trajectory defining a tip path plane. The device includes a sensor for measuring an angular velocity of a blade about a pitch axis. The device thus makes it possible to determine a state of the rotor, comprising, for example, estimates of a longitudinal cyclic pitch and of a lateral cyclic pitch of the blade with respect to the tip path plane.

An adjustable balance module for the balancing of rotatable blades. The adjustable blade balance module includes a frame that retains and covers an adjustment screw with a mass that translates along a threaded shaft of the adjustment screw. The adjustment screw is incrementally controlled by an adjustment dial that is accessible from an exterior surface of the blade.

The present invention includes a rotor-blade span-balancing system, including a span-balance pocket in a surface of a rotor blade; a cover operably configured to cover the span-balance pocket, wherein the cover is operably configured to be substantially flush with the surface of the rotor blade surface when covering the span-balance pocket, and wherein the cover includes a cover boss for reacting centrifugal force of the cover into the rotor blade; and one or more span-balance weights attached to the cover to span-balance the rotor blade.