US Patent 9394798 Gas turbine engines with turbine airfoil cooling

An airfoil for a gas turbine engine is provided. The airfoil includes a body with a leading edge, a trailing edge, a first side wall extending between the leading edge and the trailing edge, and a second side wall extending between the leading edge and the trailing edge. The body defines an interior cavity. The airfoil includes an interior wall disposed within the interior cavity of the body and extending between the first wall and the second wall to define a supply chamber and a leading edge chamber. The interior wall defines a cooling hole with a base portion and a locally extended portion to direct cooling air from the supply chamber to the leading edge chamber such that the cooling air impinges upon the leading edge.