A gas turbine engine includes a fan having a plurality of fan blades configured to rotate about a central axis of the gas turbine engine. Each fan blade is configured to pivot about a pivot axis that extends radially away from the central axis to vary a pitch of the fan blade. The fan further includes a counterforce system configured to resist forces that urge the fan blades away from their pitch positions during operation of the gas turbine engine.

There is provided a turbofan engine for an aircraft. The turbofan engine has a core with a fan cowl and a variable pitch fan (VPF) configured to only rotate in a first rotation direction. The VPF has a plurality of fan blades each configured to over-pitch to an over-pitch position relative to a feathered position. The turbofan engine has outer guide vanes (OGVs) axially disposed downstream of the VPF, and has a rotation control device to prevent the VPF from rotating in a second rotation direction opposite the first rotation direction, during an engine out (EO) condition of the turbofan engine. When the VPF is prevented from rotating during the EO condition, the fan blades are over-pitched to the over-pitch position relative to the feathered position, to achieve no or minimal air flow separation about the OGVs, and to reduce drag of the turbofan engine during the EO condition.

A variable vane actuation system for a gas turbine engine includes a stem section that forms a base and a contoured section that extends from the base along an axis. A vane arm comprising a claw section received onto the contoured section and a fastener fastened to the contoured section to load the claw section to the base.

A variable pitch fan assembly includes a plurality of rotating trunnion assemblies, a plurality of counterweight assemblies, a first unison ring gear engaged with the trunnion assemblies, and a second unison ring member that restricts out of synch movement of the counterweights relative to each other.

A turbomachine module includes a rotor supporting variable pitch blades, and an inner annular shaft, a blade pitch control device, a device for feathering at least one blade comprising at least one gas generator placed between a body and a movable member. The control device and the feathering device are situated radially between the shaft and the blades, the movable member is coupled with the at least one blade and capable, under the action of the gas generated and/or released by the generator, of being moved into a reference position wherein it entails a feathered position to the at least one blade.

A fan for a gas turbine engine is provided. The fan includes a plurality of fan blades, a disk, and a trunnion mechanism for attaching the fan blades to the disk. The disk can be formed of a plurality of individual disk segments, with the trunnion mechanism attaching one of the plurality of fan blades to a respective disk segment. A retention member is also provided. The retention member includes a means for catching a portion of the trunnion mechanism should a primary attachment system of the trunnion mechanism fail.

Fan module with variable-pitch blades for a propulsion system that includes: a rotor supporting the blades, and including an internal shaft and an external shroud, defining between them a space; a pitch control device (22) of the blades that includes a load transfer bearing; a feathering device of the blades; said feathering device includes at least one lever that is articulated around a fixed axis (A) in relation to the rotor, where said lever features a first end located outside said space and a second end located inside said space, and where a flyweight is fastened to the first end and the second end is coupled to said bearing.

A turbomachine module with a longitudinal axis, the module comprising: a rotary casing rotatable around the longitudinal axis and arranged to carry a propeller provided with a plurality of blades; a system for changing the pitch of the blades of the propeller comprising: a control, and a mechanism for varying the pitch of the blades of the propeller connecting these blades to the control, wherein the control comprises a rotary actuator comprising a control body and a reference body which is integral with the rotary casing, and wherein the mechanism for varying the pitch comprises a synchronization ring which is driven in rotation around the longitudinal axis by the control body and which is guided in rotation on the rotary casing, the synchronization ring being connected to the blades.

A gas turbine engine includes a core turbine engine and a fan mechanically coupled to the core turbine engine. The fan includes a plurality of fan blades, each fan blade defining a base and an inner end along a radial direction of the gas turbine engine. The fan also includes a hub covering the base of each of the plurality of fan blades. Further, the fan includes one or more bearings for supporting rotation of the plurality of fan blades. The one or more bearings define a fan bearing radius along a radial direction of the gas turbine engine. Similarly, the hub defines a hub radius along the radial direction of the gas turbine engine. The ratio of the hub radius to the fan bearing radius is less than about three, providing for desired packaging of the various components within the fan of the gas turbine engine.

A pitch actuation system for a turbomachine propeller, comprising an actuator with a movable portion configured to be connected to blades of the propeller in order to rotate them relative to the blade-pitch setting axes, wherein the actuator is an electromechanical actuator and comprises: blade-pitch control having a transmission screw rotated about an axis; a nut through which the transmission screw passes; and a member configured to engage with the blades in order to move the blades, wherein the nut is connected to the member via a decoupler configured such that a translational movement of the nut causes a translational movement of the member, but rotational movement of the member does not cause rotational movement of the nut.