Through-casing guide vane mechanism for gas turbine engines

An aircraft gas turbine engine comprising:

• a compressor section and a turbine section arranged along an engine axis, wherein at least one of the compressor section and the turbine section comprises:
• a housing;
• a rotor arranged within the housing and comprising a plurality of blades;
• a stator arranged within the housing and comprising a plurality of guide vanes, wherein the plurality of guide vanes are arranged radially inward from the housing and about the engine axis;
• a unison ring operably connected to each of the plurality of guide vanes, the unison ring configured to rotate about the engine axis to impart rotation to each of the plurality of guide vanes about a respective guide vane axis;
• and
• a guide vane actuator assembly comprising:
• an actuator;
• an actuating rod;
• a boss rod operably connected to the actuating rod;
• a jointed boss member defining a through hole through the housing and supporting the boss rod;
• and
• a connecting rod operably connecting the boss rod to a bracket, wherein the bracket is connected to the unison ring,
• wherein the actuator is configured to apply an actuating force to the actuating rod, through the boss rod and the connecting rod, to apply the actuating force to the unison ring and control the rotation of the plurality of guide vanes about the respective guide vane axes.