Structural health monitoring and protection systems and methods are provided. System and methods utilize structural information and/or enhanced built in testing capabilities for detecting failure modes that may cause damage to a structure. Systems and methods herein may protect a structure by mitigating one or more incorrect forces. The structure may be an aircraft, a rotary wing aircraft, or any other physical structure subject to vibrations and receptive to canceling of those vibrations.

A hover aircraft rotor having a hub which rotates about an axis and has a number of blades; a drive shaft connectable to a drive member of the aircraft and connected functionally to the hub to rotate the hub about the axis; and damping means for damping vibration transmitted to the shaft, and which include a mass designed to oscillate, in use, to oppose transmission to the shaft of vibration generated by rotation of the blades; the mass being free to oscillate parallel to the axis, to oppose transmission to the shaft of vibration having main components along the axis.

The present invention includes a damper assembly, method and kit to provide dampening to an airframe comprising: a mass to dampen the vibration of the airframe; one or more wire rope isolators having a first and a second portion, wherein the mass is attached to the one or more wire rope isolators and the mass is isolated from the airframe by the one or more wire rope isolators; and a first fastener and a second fastener, wherein the first fasteners attaches to the first portion of the wire rope isolator to the mass, and the second fastener attaches the second portion of the wire rope isolator to the airframe to dampen vibration of the airframe.

A resonator provided with a heavy member comprising a casing fastened a spring blade. The heavy member comprises a set of masses that is movable in translation in said casing along a longitudinal direction. A wormscrew driven by drive means is engaged in a slider nut of said set of masses. The set of masses comprises two masses that are slidable respectively in two cylindrical spaces of the casing. Each mass presents at least two presser means interposed between the mass and the casing, each presser means comprising a groove formed in a circumference of a mass, each presser means comprising at least one resilient member arranged in said groove and a split ring pressed against the casing by said at least one resilient member of the presser means.

An antivibration suspension system of an aircraft, the antivibration suspension system comprising a lever and an oscillating mass. The antivibration suspension system comprises a mechanical motion amplifier device interposed between the lever and the oscillating mass, the motion amplifier device being provided both with a mechanical inlet constrained to move in rotation with the lever about a control axis and with a mechanical outlet driving rotary movement of the oscillating mass.

In an embodiment the invention includes a method of mounting an engine in a rotary wing aircraft. The method includes providing a rotary wing aircraft having an aircraft body supported in flight through an exterior air space by a rotary wing system rotating with an operational rotating frequency (P) with a plurality of (N) rotary wings, the rotary wing aircraft body having a persistent in flight operational rotating frequency vibration. The method includes providing a first engine, the first engine for providing power to rotate the rotary wing system at the rotary wing system operational rotating frequency (P).

A rotor damping system includes a rotor blade defining opposed leading and trailing edges, wherein the rotor blade has flexibility in an edgewise direction defined between the leading and trailing edges. A spar is mounted within the rotor blade, wherein the spar is stiff against flexure in the edgewise direction. A damper is operatively connected to the spar for damping relative motion of the spar and blade.

The invention relates to a device (12) for a non-streamlined propeller (6, 7) with blades (10) having variable pitch of a turbomachine (1), the device comprising a support (15) intended to support a blade (10) and including a cylindrical foot (17), a bearing comprising a radially internal annular section (20) and a radially external annular section (21) capable of pivoting with respect to each other, the foot (17) being mounted in said internal section (20) of the bearing. The device comprises a hub (27) mounted in the foot (17), said hub (27) including a rim (29) comprising a face (30) coming to bear on the radially internal annular section (20) of the bearing, the hub (27) and the foot (17) of the support (15) comprising complementary engagement elements (18, 28) interacting with a locking component (23).

In an embodiment the system includes a method of mounting an engine in a rotary wing aircraft. The method includes providing a rotary wing aircraft having an aircraft body supported in flight through an exterior air space by a rotary wing system rotating with an operational rotating frequency (P) with a plurality of (N) rotary wings, the rotary wing aircraft body having a persistent in flight operational rotating frequency vibration. The method includes providing a first engine, the first engine for providing power to rotate the rotary wing system at the rotary wing system operational rotating frequency (P).

A vibration control system for a rotorcraft includes at least one of an integrated actuator and an intermediate actuator associated with a first source of vibration, a sensor configured to sense vibration from the first source of vibration, a dedicated actuator configured for association with a fuselage, and a controller configured to receive information from the sensor and configured to control the dedicated actuator and the at least one of the integrated actuator and the intermediate actuator.