A gas turbine engine including: a first turbine rotor assembly including a plurality of first turbine rotor blades extended within a gas flowpath; and a casing surrounding the first turbine rotor assembly, wherein the casing comprises an outer casing wall extended around the first turbine rotor assembly; a plurality of vanes extended from the outer casing wall and within the gas flowpath at a location aft of the first turbine rotor assembly; and a thermal control ring positioned outward along a radial direction from the outer casing wall, and wherein the thermal control ring comprises a body and a plurality of pins, and wherein the plurality of pins extend between the outer casing wall and the body.