Variable pitch fan of a gas turbine engine

A gas turbine engine comprising:

• 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 rotatable about the fan axis and a disk;
• a pitch change mechanism operable with the plurality of fan blades to control a pitch of the plurality of fan blades;
• a counterweight connected to each respective fan blade;
• and
• a spring mechanism operably associated with each respective fan blade, the spring mechanism operable with the counterweight of each respective fan blade to counter a centrifugal twisting moment of each respective fan blade, wherein the spring mechanism comprises a non-linear spring;
• wherein each respective fan blade is coupled to a respective trunnion comprising a respective sleeve, and wherein the non-linear spring of the spring mechanism is wrapped about the respective sleeve of the respective trunnion, and wherein the non-linear spring comprises a first end directly coupled to the disk and a second end directly coupled to the respective trunnion of each respective fan blade.

A gas turbine engine comprising:

• 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 rotatable about the fan axis and a disk;
• a pitch change mechanism operable with the plurality of fan blades to control a pitch of the plurality of fan blades;
• and
• a plurality of spring mechanisms, each spring mechanism of the plurality of spring mechanisms operably associated with each respective fan blade of the plurality of fan blades, each respective spring mechanism creating a spring twisting moment on the respective fan blade to counter a centrifugal twisting moment of the respective fan blade, wherein each spring mechanism of the plurality of spring mechanisms comprises a non-linear spring;
• wherein each respective fan blade is coupled to a respective trunnion comprising a respective sleeve, and wherein the non-linear spring of each spring mechanism of the plurality of spring mechanisms is wrapped about the respective sleeve of the respective trunnion;
• and
• wherein the non-linear spring comprises a first end directly coupled to the disk and a second end directly coupled to the respective trunnion of each respective fan blade.