A gas turbine engine includes a compressor powered by a turbine. The turbine includes a nozzle having vanes extending between outer and inner bands. Each vane includes an internal cooling plenum and a bypass tube extending through the bands. First and second manifolds surround the outer band and are disposed in flow communication with the plenums and bypass tubes, respectively. A bleed circuit joins the compressor to the manifolds for providing pressurized air thereto. A control valve modulates airflow to the first manifold and in turn through the cooling plenums of the vanes.