Abstract: A vane arm may comprise a first end having a first surface and a second surface opposite the first surface. A vane stem aperture may be formed through the first end of the vane arm. The first surface may define a first perimeter of the vane stem aperture. The second surface may defines a second perimeter of the vane stem aperture. The second perimeter may comprise a circular or elliptical shape. A first wedge face and second wedge face may define a portion of the vane stem aperture.

Abstract: A cam isolation system for a gas turbine engine compressor actuator includes a torque tube. The system also includes a cam bracket operatively coupled to an engine case structure, the cam bracket defining a slot. The system further includes an actuator bracket operatively coupled to the torque tube at a first end of the actuator bracket, the actuator bracket having a pin disposed within the slot of the cam bracket.

Abstract: A synchronization ring for a variable vane assembly of a gas turbine engine may include a first ring portion and a second ring portion. The first ring portion and the second ring portion may be detachably coupled together to jointly define a plurality of cylindrical bores circumferentially distributed around the synchronization ring and extending radially through the synchronization ring.

Abstract: A variable vane actuation system of a gas turbine engine is provided. The variable vane actuation system including: a variable vane; a vane stem operably associated with the variable vane, wherein the variable vane is configured to rotate with the vane stem; a vane arm having vane stem end and a vane pin end opposite the vane stem end, the vane arm being operably connected to the vane stem at the vane stem end; and a rotational variable differential transformer operably connected to the vane stem, the rotational variable differential transformer configured to detect an amount of rotation of the vane stem.

Abstract: A vane arm assembly for a gas turbine engine. The vane arm assembly includes a vane arm defining an aperture at an end thereof with an aperture wall. The vane arm assembly also includes a vane stem extending through the aperture of the vane arm. The vane arm assembly further includes a mechanical fastener retaining a position of the vane arm in the longitudinal direction of the vane stem. The vane arm assembly yet further includes an impedance ring disposed within the aperture of the vane arm and within an impedance ring groove defined by the vane stem to provide redundant position retention of the vane arm in the longitudinal direction of the vane stem.

Abstract: A vane arm may comprise a first end having a first surface and a second surface opposite the first surface. A vane stem aperture may be formed through the first end of the vane arm. The first surface may define a first perimeter of the vane stem aperture. The second surface may defines a second perimeter of the vane stem aperture. The second perimeter may comprise a circular or elliptical shape. A first wedge face and second wedge face may define a portion of the vane stem aperture.

Abstract: A synchronization ring for a variable vane assembly of a gas turbine engine may include a first ring portion and a second ring portion. The first ring portion and the second ring portion may be detachably coupled together to jointly define a plurality of cylindrical bores circumferentially distributed around the synchronization ring and extending radially through the synchronization ring.

Abstract: A bellcrank assembly for variable vane assembly of a gas turbine engine includes a first bellcrank segment. Also included is a second bellcrank segment. Further included is a bolt extending through respective interior barrels defined by the first and second bellcrank segments to couple the first and second bellcrank segments to each other. Yet further included is a torque frame wall defining an aperture, the bolt extending through the aperture.