Abstract: Apparatus for controlling an amount of cooling air provided to a wheelspace of a turbine section of a gas turbine includes a sensor that senses a temperature of the wheelspace and provides a sensed temperature signal. The apparatus also includes a processor, responsive to the sensed temperature signal, that determines if the temperature of the wheelspace exceeds a desired value. If the temperature of the wheelspace exceeds the desired value, the processor activates an actuator control signal to control movement of a cooling air control valve to allow a greater amount of cooling air sourced from a compressor section of the gas turbine or from a cooling air cooler which receives air from the compressor section of the gas turbine to flow to the wheelspace, thereby cooling the temperature of the wheelspace.