An aircraft comprising a fuselage and propelled by a turbine engine having two coaxial and contrarotating fans, the turbine engine comprising a power turbine having two contrarotating rotors, one of which drives a fan upstream from the turbine, the other a fan downstream from the turbine, each fan comprising a ring of blades, and the assembly of the fans and the power turbine being incorporated at the rear of the fuselage, in the extension of same. The aircraft comprises, for at least one of the fans, a device for blocking the rotation of the fan and a device configured to modify the pitch of the blades of the fan in such a way as to make it operate as a flow straightener with respect to the other fan.

A system is configured to change the pitch of blades of at least one turbine engine propeller provided with multiple blades. The system includes a control means acting on a connecting mechanism connected to the blades of the propeller. The control means includes a stationary body and a movable body translatable along a longitudinal axis (X) relative to the stationary body and defining two chambers. A fluid supply means is configured to be connected to a fluid supply source and to supply the chambers. The fluid supply means includes at least one channel. The channel is arranged and extends along an axis (Q) parallel to the longitudinal axis in an overthickness of a wall of the stationary body, the overthickness extending radially inside relative to the longitudinal axis.

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.

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.

The invention relates to a hybrid vertical take-off and landing drone comprising at least two substantially parallel fixed wings (12, 14) each comprising at least two fins (16a, 16b, 18a, 18b) distributed on either side of a roll axis (200) of the drone and individually controlled, characterized in that it comprises at least two counter-rotating rotors (20a, 20b) with a collective pitch system (24a, 24b) and a swashplate (26a, 26b), which are arranged between two wings on either side of the roll axis (200a), individually controlled and articulated so as to allow independent tilting of each rotor on a tilt axis (22a, 22b) substantially parallel to the pitch axis of the drone, the rotational axis of the blades of each rotor being substantially perpendicular to said tilt axis.

A turbomachine including at least two unducted propellers, one of which is an upstream propeller and one a downstream propeller, the upstream propeller including a plurality of blades, at least one first blade of which has a different length from that of a second blade.

An actuator rod assembly for a blade pitch control system is provided herein. The actuator rod assembly includes a tubular outer rod and an inner rod. The outer rod has a first end and a second end. The inner rod has a first end and a second end and extends through the tubular outer rod. The inner rod is tensioned against the tubular outer rod so as to place the outer rod in compression.

An assembly for an aircraft turbine machine including a receiver for a pair of open rotor contra-rotating propellers, the assembly including a duct, ancillaries routed inside the duct, an attachment case, attachment device of the duct on an annular installation portion of the case. The attachment device in an assembled configuration include a split ring fitted with internal projections housed inside orifices in the duct; a radial loading surface of the ring made on the portion the surface being tapered and narrowing along a first axial direction, and being in contact with a peripheral surface of the complementary shaped tapered split ring; device of axially loading the ring along the first direction, the device being blocked in the axial direction on the portion.

A propeller system has a pair of rotors and a pair of blade sets and at least one a drive input to drive a first of the rotors and blade sets and a second of the rotors and blade sets. The blade sets are positioned such that when both are driven, air will be driven across the first blade set and then across the second blade set. There is a pitch change mechanism to change an angle of incidence of the blade in at least one blade sets. There is a device for selectively stopping rotation of at least one of the first or second rotor and blade set while still allowing rotation of the other rotor and blade set. The pitch change mechanism of the stopped blade set can still change the angle of incidence when the device has stopped rotation. A method is also disclosed.

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.