A variable pitch bladed disc including a plurality of blades, each being of variable pitch about a blade axis of rotation and having a root, the plurality of blades including at least one first blade and at least one second blade, a plurality of rotor connecting shafts, each shaft having a root and a tip, the root of each blade being mounted on the tip of a corresponding rotor connecting shaft via a pivot so as to allow each blade to be rotated about the blade axis of rotation, the first blade having a first rotation axis inclination such that the rotation axis thereof is inclined in a fixed manner with respect to a radial axis passing through the root of the corresponding shaft, and the second blade has a second rotation axis inclination different from the first rotation axis inclination.

A sealing arrangement is provided between inner and outer coaxial ring-shaped walls of an aircraft engine. The outer wall has an axial end with a U-shaped cross-section parallel to axis, the opening therein being oriented axially in a first direction. The inner wall has an axial end with a U-shaped cross-section parallel to axis, the opening therein being oriented axially in the opposite direction. The U-shaped end of the outer wall includes a ring-shaped free edge axially engaged in the opening in the axial end of the inner wall. The U-shaped end of the inner wall includes a ring-shaped free edge axially engaged in the opening in the axial end of the outer wall. The walls define therebetween a ring-shaped gas channel having a substantially S-shaped axial cross-section.

An aircraft turbine engine has a pair of rotating and non-ducted propellers. An upstream propeller has an outer diameter D1 and a downstream propeller has an outer diameter D2. The engine further includes a system for varying the diameter D2. The downstream propeller includes an annular row of blades, each of which is configured to be mounted telescopically in the radial direction (R) in an outer fan duct.

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 aircraft with rear mounted engines, comprising a vertical tail plane and a horizontal tail plane, in which the engines are mounted on top of the horizontal tail plane, such that the horizontal tail plane comprises an inner fixed part attached to the fuselage of the aircraft, the inner fixed part comprising an elevator, and two outer movable parts, each one of the outer movable parts being located at each side end of the horizontal tail plane which is furthest away from the fuselage of the aircraft, such that both the inner fixed part and the outer movable parts are at least partially subjected to a flow coming from the engines when the engines are in use.

The invention relates to an aircraft propulsion system (100) intended for being built into the rear of an aircraft fuselage, the propulsion system comprising at least two gas generators (102a, 102b) supplying a power turbine (104) having two counter-rotating turbine rotors (104a, 104b) for driving two fans (112a, 12b), and separate air inlets (106a, 106b) for supplying each gas generator, characterised in that it comprises an electrical drive device (140) configured to rotate at least one of the turbine rotors, at least one electrical generator (142a, 142b) configured to transform part of the energy of the flow from the gas generators into electrical power and an electric motor (146) supplied by said electrical generator and capable of rotating at least one of the turbine rotors, said electrical generator being installed on one of said gas generators, and in that said turbine rotor is capable of being rotated simultaneously by a flow from said gas generators and by the electrical drive device.

A rotating assembly such as a counter-rotating propeller system or a turbofan includes a first rotating part rotatable relative to a second part, the first and second parts mounted on a common axis, a combustion engine arranged to rotate the first part, and an electric motor connected to drive the second part. In a first drive mode, the combustion engine rotates the first part in first direction relative to the axis while the electric motor drives the second part in a second, opposite direction relative to the axis and in a second drive mode, the combustion engine rotates the first part in the first direction and the electric motor does not drive the second part in the second, opposite direction.

A propulsion system, the propulsion system comprising a rotating element, a stationary element, and an inlet between the rotating element and the stationary element, wherein the inlet passes radially inward of the stationary element; wherein the inlet passes radially inward of the stationary element; wherein the inlet leads to an inlet duct containing a ducted fan having an axis of rotation and a plurality of blades; and wherein the inlet duct divides into a first duct and a second duct, separate from the first duct. A method of operating a propulsion system, comprising the steps of: operating a first rotating fan assembly to produce a first stream of air; directing a portion of the first stream of air into a second ducted rotating fan assembly; operating the second ducted rotating fan assembly to produce a second stream of air; dividing the second stream of air into a core stream and a fan stream; and directing the core stream into a gas turbine engine core.

A fan system includes a rotor having plurality of blades and a ring airfoil, the plurality of blades being rotatably joined to a hub and the ring airfoil. The fan system may include a second contra-rotationally disposed rotor having a plurality of blades and a ring airfoil. The first and second ring airfoils having a cambered shape and an angle of attack between about 5 degrees and about 45 degrees. Passive leading edge slats are attached to the ring airfoil and are configured to open and close using springs.

An electronic control system (30) for a turbopropeller engine (12) having a gas turbine (20) and a propeller assembly (13) coupled to the gas turbine (20), controls propeller operation based on a pilot input request, via generation of a driving quantity (Ip) for an actuation assembly (29) designed to adjust a pitch angle () of propeller blades (2) of the propeller assembly (13). The control system (30) envisages: a propeller speed regulator (39), receiving at its input a propeller speed error (ep), indicative of a difference between a propeller speed measure (Nr) and a propeller speed demand (Nrref), and generating at its output, based on the propeller speed error (ep), a first control quantity (Outi); a propeller pitch regulator (42), receiving at its input a propeller pitch error (ep), indicative of a difference between a propeller pitch demand ( ) and a pitch position measure (), and generating at its output, based on the propeller pitch error (ep), a first control quantity (Out2); and a priority selection stage (45), configured to implement a priority selection between the first and the second control quantities, for providing at the output the driving quantity (IP), based on the priority selection between the first and the second control quantities.