A stator vane assembly includes a platform that defines an opening. The stator vane assembly further includes an airfoil segment that includes an airfoil and a boss. The airfoil includes a leading edge, a trailing edge, a suction side wall, and a pressure side wall. The airfoil extends radially between a base and a tip. The boss extends from at least one of the base or the tip of the airfoil. The boss is disposed in the opening of the platform. The stator vane assembly further includes a mechanical retention device that couples the platform to the boss of the airfoil segment.