An aircraft control system includes a propeller shaft assembly. Also included is first rotor operatively coupled to the propeller shaft assembly, the first rotor having a first plurality of blades mounted thereto, the first blades disposed at a substantially identical nominal pitch during rotation of the first rotor, the first rotor rotatable in a first direction. Further included is a second rotor operatively coupled to the propeller shaft assembly and rotatable in a second direction, the second rotor having a second plurality of blades mounted thereto, wherein a pitch of the second blades cyclically changes during rotation of the second rotor, the first rotor and the second rotor disposed and rotated proximate a fixed wing of an aircraft about a common axis extending parallel to a longitudinal axis of the aircraft, cyclically changing the pitch of the second plurality of blades generating a moment for controlling the aircraft.

A central-positioned pitch control device used in a coaxial helicopter includes an upper propeller hub; a lower propeller hub; a first blade mounted on the outside of the upper propeller hub; a second blade mounted on the outside of the lower propeller hub; and a central-positioned pitch control device placed between the upper propeller hub and the lower propeller hub.

An aircraft control system includes a co-axial, counter-rotating propeller shaft assembly. Also included is a first rotor operatively coupled to the propeller shaft assembly, the first rotor having a first plurality of blades mounted thereto, wherein the first plurality of blades are disposed at a substantially identical nominal pitch during rotation of the first rotor. Further included is a second rotor operatively coupled to the propeller shaft assembly, the second rotor having a second plurality of blades mounted thereto, wherein a pitch of the second plurality of blades is configured to cyclically change during rotation of the second rotor.

The invention concerns a device (1) for controlling the pitch of the blades of a fan (4) rotor (3), comprising a radial shaft (6) linked to the blade, a connection rod (8) of which the axial movement controls the rotation of the radial shaft (6), characterized in that it comprises:a first part (10) that is mobile in rotation with the rotor (3) about the axis (11) of the fan (4), and on which one end of each connection rod (8) is secured,a second part (12) linked to the first part (10), andat least three cylinders (14) capable of moving said second part (12) in axial translation, and of varying the tilt of said second part, the translation and tilt of the second part (12) driving a corresponding translation and tilt of the first part (10), such that, when the first part (10) rotates, each connection rod (8) is subject to axial displacement of which the amplitude is variable and is a function of the tilt of the first part (10), making it possible to vary the pitch of the blade during the rotation of same. The invention also concerns a fan, and a method for controlling the pitch of blades.

Systems and methods are disclosed for controlling the pitch angle of a propeller and rotor assembly that selectively limit the pitch angle according to a selected mode of operation. The system comprises an actuator having forward and aft chambers, an oil transfer bearing (OTB), and a fine stop collar. The fine stop collar including a first passage in fluid communication with the OTB and forward chamber during a ground-based mode of operation, and a second fluid passage being in fluid communication with the OTB and forward chamber during a flight-based mode of operation.

Systems and methods are disclosed for controlling the pitch angle of a propeller and rotor assembly that selectively limit the pitch angle according to a selected mode of operation. The system comprises a fine stop collar defining a primary channel, an oil transfer bearing (OTB) extending across the fine stop collar, and an actuator piston engaged with a propeller blade crankshaft to vary propeller blade pitch, wherein the annular piston is positioned about the OTB in fluid communication with the primary channel.

Systems and methods are disclosed for controlling the pitch angle of a propeller and rotor assembly that minimizes circumferential loads and stresses to a pitch angle control system. The system may generally include an annular actuator, load transfer bearing (LTB), and a guide shaft is pivotally attached to the LTB to direct the LTB along an arcuate path relative to a rotor frame.

A device for feeding fluid to a hydraulic actuator for controlling a pitch of fan blades of a two-propeller turboprop, the device including: a fluid manifold secured to a rotor of the turboprop and including a cylindrical portion including at least two fluid-circulation grooves, each presenting an outlet orifice; a fluid-admission support secured to a stationary portion of the turboprop and including a cylindrical portion including at least two distinct fluid passages opening to fluid-admission tubes and each leading radially into one of the fluid-circulation grooves of the manifold; and a tub constrained to rotate with the fluid manifold and including a cylindrical portion including at least two fluid-flow channels, each fed with fluid by a respective one of the outlet orifices of the fluid dispenser, each fluid-flow channel leading to a respective chamber of a control actuator.

An aircraft turbomachine includes a speed reduction gear having an input pinion connected to a power shaft and an output pinion connected to a propeller shaft. An electric machine is integrated into the speed reduction gear and is configured to provide electrical power to the propeller shaft or to take mechanical power from the propeller shaft. The electric machine has a rotor driven in rotation about an axis coaxial with a longitudinal axis of the turbomachine and a stator connected to a casing. The input pinion includes an input shaft offset from an axis of the output pinion, and the speed reduction gear has two parallel intermediate transmission lines configured to transmit the torque from the input pinion to the output pinion to drive the rotor in rotation.

Systems and methods relate to a vehicle, such as a vertical takeoff and landing (VTOL) platform, which can include a stator and a rotor magnetically levitated by the stator. The rotor and stator can be annular, such that the rotor rotates about a rotational axis. The stator can include magnets that provide guidance, levitation, and drive forces to drive the rotor, as well as to control operation of rotor blades of the rotor that can be independently rotated to specific pitch angles to control at least one of lift, pitch, roll, or yaw of the VTOL platform. Various controllers can be used to enable independent and redundant control of components of the VTOL platform. Various communication systems, such as a communications circuit, can establish a wireless communications link between a core network and at least one respective rotor transceiver.