Abstract: A variable vane assembly for a gas turbine engine having an actuating system including a rotatable face gear and a respective pinion engaged to and extending transversely from the end of each of the moveable vanes. The teeth of each pinion define land surfaces angled with respect to adjacent ones of the land surfaces of the teeth of the face gear meshed therewith. A smallest axial distance between the adjacent land surfaces of the meshed pinion and face gear teeth define a backlash of the actuating system. At least one shim has a thickness adjusting an axial distance between the pinion and the face gear to set the backlash to a predetermined value. An engine with a compressor with a variable vane assembly and a method of adjusting angular variance in an actuating system for variable vanes are also discussed.

Abstract: A variable vane assembly for a gas turbine engine having an actuating system including a rotatable face gear and a respective pinion engaged to and extending transversely from the end of each of the moveable vanes. The teeth of each pinion define land surfaces angled with respect to adjacent ones of the land surfaces of the teeth of the face gear meshed therewith. A smallest axial distance between the adjacent land surfaces of the meshed pinion and face gear teeth define a backlash of the actuating system. At least one shim has a thickness adjusting an axial distance between the pinion and the face gear to set the backlash to a predetermined value. An engine with a compressor with a variable vane assembly and a method of adjusting angular variance in an actuating system for variable vanes are also discussed.