A method for cooling a turbine stage of a gas turbine engine comprising: overcooling a portion of a bleed air flow thereby creating an overcooled air, wherein said portion is less than 100% of said bleed air; mixing at least a portion of said overcooled air with a remainder of said bleed air flow, thereby creating a mixed air flow having a temperature within a cooling temperature range; providing said mixed air flow to an active cooling system for the turbine stage; providing a compressor bleed structure disposed in a first compressor stage and operable to remove air from said first compressor stage; providing a fluid pathway (152,154,156) connecting the compressor bleed structure to the active cooling system of a turbine stage, wherein the fluid pathway (152,154,156) includes a first fluid pathway directly connecting the output of the compressor bleed structure to a mixing plenum, a second fluid pathway connecting the output of the compressor bleed structure to an input of a heat exchanger, and a third fluid pathway connecting an output of the heat exchanger to the mixing plenum, and the mixing plenum is connected to a cooling air input of the active cooling system for the turbine stage; and bleeding air from the first compressor stage using the compressor bleed structure, wherein the first compressor stage has a fluid pressure at least equal to a pressure threshold, wherein the pressure threshold is an amount of pressure at said mixing plenum required to prevent backflow from said turbine stage active cooling system; characterized in that air removed from the compressor at the compressor bleed exceeds a first threshold temperature that is a maximum temperature at which air can provide a full cooling effect to the turbine stage, air in said third fluid pathway is overcooled below a second threshold temperature lower than the first threshold temperature, and a combined output of the third fluid pathway and the first fluid pathway is at a temperature between the first threshold and the second threshold; and in that air in said mixing plenum is mixed air comprising a mixture of air from said first fluid pathway and said third fluid pathway, and said mixed air exceeds the pressure threshold and is within an optimum cooling temperature range. overcooling a portion of a bleed air flow thereby creating an overcooled air, wherein said portion is less than 100% of said bleed air; mixing at least a portion of said overcooled air with a remainder of said bleed air flow, thereby creating a mixed air flow having a temperature within a cooling temperature range; providing said mixed air flow to an active cooling system for the turbine stage; providing a compressor bleed structure disposed in a first compressor stage and operable to remove air from said first compressor stage; providing a fluid pathway (152,154,156) connecting the compressor bleed structure to the active cooling system of a turbine stage, wherein the fluid pathway (152,154,156) includes a first fluid pathway directly connecting the output of the compressor bleed structure to a mixing plenum, a second fluid pathway connecting the output of the compressor bleed structure to an input of a heat exchanger, and a third fluid pathway connecting an output of the heat exchanger to the mixing plenum, and the mixing plenum is connected to a cooling air input of the active cooling system for the turbine stage; and bleeding air from the first compressor stage using the compressor bleed structure, wherein the first compressor stage has a fluid pressure at least equal to a pressure threshold, wherein the pressure threshold is an amount of pressure at said mixing plenum required to prevent backflow from said turbine stage active cooling system; characterized in that air removed from the compressor at the compressor bleed exceeds a first threshold temperature that is a maximum temperature at which air can provide a full cooling effect to the turbine stage, air in said third fluid pathway is overcooled below a second threshold temperature lower than the first threshold temperature, and a combined output of the third fluid pathway and the first fluid pathway is at a temperature between the first threshold and the second threshold; and in that air in said mixing plenum is mixed air comprising a mixture of air from said first fluid pathway and said third fluid pathway, and said mixed air exceeds the pressure threshold and is within an optimum cooling temperature range.