Abstract: A turbine vane-system cooling system uses three internal cooling cavities 1, 12, 13) separated by two radial walls (9, 10). The upstream cavity (11) uses a helical ramp (30) and is fed through an intake (22) at the vane root (3). The middle cavity (12) also is fed at the vane root (3) and includes a compartmented, multi-perforated lining (40). The air is exhausted from each compartment through impact orifices and enters the succeeding compartment through slots (42) and then is finally exhausted through a vane-head orifice (21). The vane side walls opposite the downstream cavity (13) have double skins with bridging elements. The air passes through these double skins but circulates centrifugally in the upstream portion (15) of the downstream cavity (13) and enters this cavity's downstream portion (16) to be exhausted through slots (19) in the trailing edge (6). A third wall (14) divides the downstream cavity (13) into two parts (15, 16).