Fail safe cooling system for turbine vanes

Embodiments of the invention relate to a turbine vane having a fail safe cooling system. According to embodiments of the invention, the vane can have multiple concentric layers of radial cooling holes extending about the vane; each layer being fluidly connected to the adjacent layer or layers. Such fluid communication can occur through one or more plenums in the vane or in the shrouds bounding the radial ends of the vane. Coolant can initially be supplied to the innermost layer of cooling holes. From there, the coolant can sequentially progress through successive outer layers. Between two adjacent layers, the coolant can flow in opposite directions. Not only does such a system provide needed cooling to the vane, but the multilayer redundant cooling system can avoid or delay catastrophic failures that can occur if the vane surface is damaged, such as by impact.