First stage turbine airfoil

A turbine blade for a gas turbine engine comprising:

• a platform having an upper surface and a lower surface, the upper surface of the platform partially defining an inner flow path wall, the lower surface having a root with a connecting joint extending radially inward from the platform, the root being connectable to a rotatable disk, wherein the rotatable disk has an axis of rotation along a longitudinal axis of the gas turbine engine;
• an airfoil extending radially outward from the upper surface of the platform relative to the axis of rotation, the airfoil having first and second three-dimensional external surfaces extending between a hub and a tip in a spanwise direction and between a leading edge and a trailing edge in a streamwise direction;
• and wherein
• the first and second external surfaces of the airfoil are substantially defined by a Cartesian coordinate array having X,Y and Z axis coordinates listed in Table 1 of the specification, wherein the Z axis generally extends radially outward from at least one of the upper surface of the platform and a longitudinal axis of the engine, the X axis generally extends normal to the Z axis in the streamwise direction, and the Y axis generally extends normal to both the X axis and the Z axis.