Gas turbine engine airfoil integrated heat exchanger

A heat exchanger apparatus includes: (a) an airfoil (42) having opposed pressure and suction sides (54, 52), a root (50), a tip (48), and spaced-apart leading and trailing edges (44, 46); and (b) a plenum (62,162,262) integrally formed within the airfoil (42) which is configured to receive a flow of circulating working fluid; and (c) inlet and outlet ports (72, 74) communicating with the plenum (62,162,262) and an exterior of the airfoil (42).