Abstract: The first stage 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 value is non-dimensional along the bucket centerline coincident with a turbine radius and convertible to a Z distance in inches from the turbine axis by multiplying the Z value by the height of the airfoil and adding the root radius to the result. The X and Y 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.

Abstract: The first stage 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 value is non-dimensional along the bucket centerline coincident with a turbine radius and convertible to a Z distance in inches from the turbine axis by multiplying the Z value by the height of the airfoil and adding the root radius to the result. The X and Y 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.

Abstract: A gas turbine moving blade includes a platform which is undercut with a groove. The groove extends from the concave side to the trailing edge side of the platform, where the groove exits the platform. The groove has a depth which will enter a stress line causing a change to the load path direction away from the trailing edge. The location and depth of the groove reduces both high thermal stress and mechanical stress arising at a connection portion of a blade trailing edge and the platform of the gas turbine air cooled moving blade during transient engine operation as well as steady state, full speed, full load conditions.