a high compression ratio compressor having multiple stages of airfoils to produce the high pressure rations , where the last stage airfoils are cooled by drawing heat away from the airfoils using a heat pipe , and then passing cooling air through a heat exchanger associated with the heat pipe to draw heat away from the heat pipe . the cooling air used for cooling the airfoils is bled off from an earlier stage than the last stage and then discharged into a stage upstream from the bleed off location .