Method of making an air cooled vane with film cooling pocket construction

The method of manufacturing an air cooled stator vane for a gas turbine engine including the steps of;

• casting a shell shaped in an airfoil with an outer curvature defining a leading edge, a trailing edge and a mid-body portion defining a suction side and a pressure side and defining a central passage;
• forming in the step of casting radially extending lips on the suction side and the pressure side adjacent the leading edge and the trailing edge:
• stamping out from a blank of sheet metal stock a corrugated sheath having peaks and valleys and sized to be contiguous with the mid body portion and to extend to the lips;
• stamping out from a blank of sheet metal stock a pair of sheaths dimensioned to be contiguous with the mid-body portion and to fit on the pressure side and the suction side;
• p1 forming in the step of stamping a plurality of apertures in the pair of sheaths to form rows of apertures and forming with the sheet metal forming the apertures dimples that define with a portion of the corrugated sheath passages communicating with the apertures;
• drilling a plurality of holes in the corrugated sheath adjacent the peaks to communicate with the passages at a point remote from the apertures;
• drilling a plurality of holes in the mid-body portion to communicate with the central passage for communicating the apertures with the central passage;
• and
• joining valleys of the corrugated sheath to the mid-body portion and said lips and the pair of sheaths to the valley of the corrugated sheath.