Methods and apparatus to reduce deflection of an airfoil are disclosed. An example apparatus disclosed herein includes a plate including an aperture, the airfoil disposed in the aperture, and a damper operatively coupled between the plate and a hub of the airfoil, the damper to transform flexural deflection of the airfoil to radial deflection of the plate.

A turbomachinery engine can include a fan assembly with a plurality of variable pitch fan blades. The fan blades are configured such that they define a first VPF parameter and a second VPF parameter. The first VPF parameter is within a range of 0.10 to 0.40 and is defined as the hub-to-tip radius ratio divided by the fan pressure ratio. The second VPF parameter is within a range of 1-30 lbf/in.sup.2 and is defined as the bearing spanwise force divided by the fan area. In certain examples, the turbomachinery engine further includes a pitch change mechanism, a vane assembly, a core engine, and a gearbox.

The present invention relates to a fan rotor with variable pitch blades, comprising a rotor disc, equipped at its periphery with a plurality of rotary fasteners (16), each fastener (16) comprising a cell (17) for receiving the root (150) of a blade (15). This rotor is characterised in that an elongated wedge (2) and a prestressing rod (3) with at least one cam (33) are also arranged in each cell (17), the bottom of the cell (17) comprising as many retraction cavities (173) as the rod (3) comprises cams (33), in that the prestressing rod (3) is interposed between the wedge (2) and the bottom (171) of the cell (17), so that said cam (33) is facing a corresponding retraction cavity (173) and in that the prestressing rod (3) can rotate about its longitudinal axis (X2-X2), between a rest position, in which the cam (33) is housed in the retraction cavity (173), and an armed position, in which the cam (33) exerts a radial pressure on the central region (22) of the wedge (2) so as to move the wedge (2) towards the blade root (150).

A propulsion assembly for an aircraft comprising a dual-flow turbine engine equipped with a fan, an aerodynamic outer shroud acting as a nacelle as well as a mounting pylon, the propulsion assembly having a secondary flow path defined by an outer radial defining surface formed by the shroud, the turbine engine including stator vanes, and the mounting pylon comprising a part housed in the secondary flow path, referred to as upstream part. According to the invention, the upstream part of the pylon extends radially from the inner radial defining surface, along a radial pylon height strictly less than a total radial height of the secondary flow path, and the upstream part of the pylon extends in the downstream direction from a root part of one of the stator vanes.

A gas turbine engine may have a fan section that includes a variable pitch mechanism for changing the pitch of fan blades. The gas turbine engine may include a fan hub that is rotatable about an engine central longitudinal axis of the gas turbine engine and a blade receiver that is for holding a fan blade and that is rotatably coupled to the fan hub and may be rotatable about a radial axis of the gas turbine engine. The gas turbine engine may include a spring element disposed between the fan hub and the blade receiver to bias the blade receiver radially outward and an annular retaining ring may be disposed around the radial axis and between the fan hub and the blade receiver to limit radially outward movement of the blade receiver to prevent the blade receiver from decoupling and disengaging from the fan hub.

A variable pitch fan for gas turbine engine is provided. The variable pitch fan includes a plurality of fan blades rotatably coupled to a disk and an actuation assembly for changing a pitch of each of the plurality of fan blades. The actuation assembly generally includes an actuation member operably connected to at least one of the plurality of fan blades and a pin. The pin is movable between a first position in which the pin is positioned at least partially in a channel defined in the actuation member, and a second position. The pin blocks movement of the actuation member relative to the pin past a range defined by the channel when in the first position. The actuation assembly further includes a retraction system for selectively engaging the pin in moving the pin from the first position to the second position.

A gear pump is described with at least two intermeshing gearwheels which are each rotationally fixedly connected to a shaft and separate a suction side from a delivery side. The shafts are mounted in a housing. One of the shafts can be brought into active connection with a drive unit and the other of the shafts can be brought into active connection with a pressure-control device which is to be driven by the drive unit via the two shafts. Furthermore, a drive device with the gear pump is proposed for setting an angle of attack of propeller blades of an adjustable-pitch propeller. In addition, an adjustable-pitch propeller having the drive device is described.

A variable-pitch vane including a plurality of propeller blades (2). Each blade has a variable pitch according to a blade rotational axis (A1) and a root (201). A plurality of rotor connecting shafts (6), each shaft having a foot (602) and a head (601). The root (201) of each blade is mounted on the head (601) of a rotor connecting shaft via a pivot (8) in such a way as to allow each blade (2) to rotate according to the blade rotational axis (A1), in which each blade (2) has a blade pitch, such that the blade rotational axis (A1) is inclined relative to a radial axis (A2) passing through the foot (602) of the corresponding shaft.

A gas turbine engine may have a blade receiver for holding a fan blade, wherein the blade receiver is rotatable about a radial axis of the gas turbine engine. The gas turbine engine may also include a variable pitch mechanism comprising an actuation arm. The gas turbine engine may also include a splined index ring disposed between the actuation arm of the variable pitch mechanism and the blade receiver. The splined index ring may include an outer spline and an inner spline.

There is disclosed a variable vane actuation arrangement 100 comprising a unison ring 34 configured to pivot a plurality of variable vanes 26 and a drive assembly 102 for driving rotation of the unison ring 34, comprising a drive 104 and a flexible line 106 extending from a ring anchor point 110 on the unison ring 34 to the drive 104. The ring anchor point 110 is positioned such that a portion of the flexible line 106 extending towards the drive 104 wraps around the unison ring 34, whereby tension in the flexible line 106 is applied to the ring anchor point 110 in a direction tangential to the unison ring 34.