A pitch control mechanism includes: a rotor structure configured for rotation about a longitudinal axis; a row of blades carried by the rotor structure, each blade having an airfoil and a trunnion mounted for pivoting movement relative to the rotor structure, about a trunnion axis which is perpendicular to the longitudinal axis; a unison ring interconnecting the blades; an actuator connected to the unison ring and the rotor structure, operable to move the unison ring relative to the rotor structure; at least one moveable counterweight carried by the rotor structure, remote from the blades; and an interconnection between the blades and the counterweight, such that movement of the counterweight causes a change in the pitch angle of the blades.

The invention relates to the field of aerial propellers, in particular the field of variable-pitch propellers, specifically for unducted fans. More specifically, the invention relates to a pivot (15) for a blade (14) of a propeller (3a, 3b), the pivot including at least a proximal portion (15a) made of metal and suitable for being retained in a radial orifice of a propeller hub, while being capable of turning in said orifice about a longitudinal axis (Z) of the pivot (15), and a distal portion (15b) including a receptacle (20) suitable for retaining a blade root, and at least one arm (17) of organic matrix composite material extending laterally relative to said longitudinal axis (Z) and supporting a flyweight (16).

A gas turbine engine includes a turbomachine comprising a compressor section, a combustion section, and a turbine section arranged in serial flow order. A fan defining a fan axis and comprising a plurality of fan blades is rotatable about the fan axis. A pitch change mechanism is operable with the plurality of fan blades to control a pitch of the plurality of fan blades. A counterweight is connected to each respective fan blade. A spring mechanism is operably associated with each fan blade of the plurality of fan blades to create a spring twisting moment on the respective fan blade that is counter to a centrifugal twisting moment of the respective fan blade.