A rotor comprising a hub and a plurality of lift assemblies. Each lift assembly is connected to two adjacent lift assemblies respectively by a first damper and a second damper. The first damper is hinged to a lift assembly about a first axis, and the second damper is hinged to said lift assembly about a second axis. A first plane contains a lead-lag axis of the lift assembly and orthogonally to the pitch axis of the lift assembly. The first axis is situated in a volume lying between the first plane and an axis of rotation of the rotor, the second axis being positioned outside said volume.

A rotor comprising a hub and a plurality of lift assemblies. Each lift assembly is connected to two adjacent lift assemblies respectively by a first damper and a second damper. The first damper is hinged to a lift assembly about a first axis, and the second damper is hinged to said lift assembly about a second axis. A first plane contains a lead-lag axis of the lift assembly and orthogonally to the pitch axis of the lift assembly. The first axis is situated in a volume lying between the first plane and an axis of rotation of the rotor, the second axis being positioned outside said volume.

A system can include a flight controller for an aircraft that includes an electric motor that drives blades with a variable pitch, where the flight controller receives a command to change a flight characteristic of the aircraft and creates a torque command and a revolutions per minute (RPM) command. The system can also include a propulsion assembly, where the propulsion assembly creates a current command based at least in part on the torque command and the RPM command, creates a blade pitch command based at least in part on the torque command and the RPM command, communicates the current command to the electric motor to change a mechanical output of the electric motor, and communicates the blade pitch command to blade actuators to control the pitch of the blades. The current command and the blade pitch command cause the blades of the aircraft to rotate at a predetermined RPM.

A system can include a flight controller for an aircraft that includes an electric motor that drives blades with a variable pitch, where the flight controller receives a command to change a flight characteristic of the aircraft and creates a torque command and a revolutions per minute (RPM) command. The system can also include a propulsion assembly, where the propulsion assembly creates a current command based at least in part on the torque command and the RPM command, creates a blade pitch command based at least in part on the torque command and the RPM command, communicates the current command to the electric motor to change a mechanical output of the electric motor, and communicates the blade pitch command to blade actuators to control the pitch of the blades. The current command and the blade pitch command cause the blades of the aircraft to rotate at a predetermined RPM.

A hydroelastic damper comprising at least a first resilient assembly that is provided with a first inner strength member engaged at least in part in a first outer strength member, a first resilient member providing resilient return for the first outer strength member and the first inner strength member towards a rest position (POSREP). The hydroelastic damper comprises at least one hydraulic assembly provided with a first hydraulic chamber and a second hydraulic chamber in communication with each other via a connection provided in a first wall of the hydraulic assembly. A first floating piston is movable at least in translation along the longitudinal axis relative to the first inner strength member and to the first outer strength member, the first hydraulic chamber being defined at least by the first floating piston and the first wall in order to protect the first resilient member.

A monolithic blade of a rotorcraft rotor, the blade comprising at least locally an airfoil zone having a pressure side face and a suction side face. The invention is remarkable in that the blade has a root zone including a finger with a spherical bearing surface arranged at a root end of the blade, a recess suitable for receiving a laminated spherical bearing, and a flexible portion having a preferred direction of deformation in bending about a flapping axis of the blade, the flexible portion being arranged between the finger and the recess.

A monolithic blade of a rotorcraft rotor, the blade comprising at least locally an airfoil zone having a pressure side face and a suction side face. The invention is remarkable in that the blade has a root zone including a finger with a spherical bearing surface arranged at a root end of the blade, a recess suitable for receiving a laminated spherical bearing, and a flexible portion having a preferred direction of deformation in bending about a flapping axis of the blade, the flexible portion being arranged between the finger and the recess.

A method of manufacturing a control cuff for a rotor blade of a hinge and bearingless rotor. The method comprises at least the steps of: manufacturing an outer shell, manufacturing a stiffener member by means of an automated process, inserting the stiffener member into the outer shell, and bonding the stiffener member to the outer shell.

A method of manufacturing a control cuff for a rotor blade of a hinge and bearingless rotor. The method comprises at least the steps of: manufacturing an outer shell, manufacturing a stiffener member by means of an automated process, inserting the stiffener member into the outer shell, and bonding the stiffener member to the outer shell.

An aircraft rotor assembly has a central hub and a plurality of rotor blades coupled to the hub for rotation with the hub about an axis, each blade having a Lock number of approximately 5 or greater. A lead-lag pivot for each blade is formed by a flexure coupling the associated blade to the hub. Each pivot is a radial distance from the axis and allows for in-plane lead-lag motion of the associated blade relative to the hub, each pivot allowing for in-plane motion from a neutral position of at least 1 degree in each of the lead and lag directions. Elastic deformation of the flexure produces a biasing force for biasing the associated blade toward the neutral position, and the biasing force is selected to achieve a first in-plane frequency of greater than 1/rev for each blade.