Abstract: A turbine bucket airfoil has a conical fillet about the intersection of the airfoil tip and tip shroud having a nominal profile in accordance with coordinate values of X and Y, offset 1, offset 2 and Rho set forth in Table I. The shape parameters of offset 1, offset 2 and Rho define the configuration of the fillet at the specified X and Y locations about the fillet to provide a fillet configuration accommodating high localized stresses. The fillet shape may be parabolic, elliptical or hyperbolic as a function of the value of the shape parameter ratio of D1 D1 + D2 at each X, Y location where D1 is a distance between an intermediate point along a chord between edge points determined by offsets O2 and O2 and a shoulder point on the fillet surface and D2 is a distance between the shoulder point and an apex location at the intersection of the airfoil tip and tip shroud.

Abstract: Third stage turbine buckets have airfoil profiles substantially in accordance with Cartesian coordinate values of X, Y and Z set forth Table I wherein X and Y values are in inches and the Z values are non-dimensional values from 0 to 1 convertible to Z distances in inches by multiplying the Z values by the height of the airfoil in inches. The X, Y and Z distances may be scalable as a function of the same constant or number to provide a scaled up or scaled down airfoil section for the bucket. The nominal airfoil given by the X, Y and Z distances lies within an envelop of ±0.160 inches in directions normal to the surface of the airfoil.