Abstract: The cooling system for the nozzle edges includes a chamber containing a cooling medium. First and second elongated plenums are disposed along opposite side edges of each platform. Inlet passages communicate cooling medium from the chamber into each plenum. Outlet passages from each plenum terminate in outlet holes in the side edges of the platform to cool the gap between adjacent nozzle segments. Passageways communicate with each plenum and terminate in film cooling holes to film cool platform surfaces. In each plenum, the inlet passages are not in direct line-of-sight flow communication with the outlet passages and passageways.