Abstract: A process for producing a small crack in a turbine rotor blade for use in training inspectors to be qualified for inspecting blades with small crack, where each blade is vibrated in order to initiate a small crack under observation using an IR camera that can detect for a small crack, and when a small crack at a desired size is produced on the blade, the vibration is stopped and the blade removed and then used in a training process to train and qualify an inspector for an inspection process.

Abstract: An inner rotor shaft for use in a small twin spool gas turbine engine, the inner rotor shaft having a hollow middle section formed of a smaller diameter hollow section on a compressor end and a larger diameter hollow section on the turbine end of the shaft. Solid shaft end extend from the hollow section to form a forward solid shaft end to secure the fan rotor disk and an aft solid shaft end to secure the turbine rotor disk. A parabolic shaped transition section joins the forward shaft end to the smaller diameter hollow section, and a conical shaped transition section joins the aft shaft end to the larger diameter hollow section. A conical shaped transition piece joins the two hollow sections together to form an inner rotor shaft that can fit within a minimal space between the compressor rotor disk and the annular combustor assembly of the engine.

Abstract: An inner rotor shaft for use in a small twin spool gas turbine engine, the inner rotor shaft having a hollow middle section formed of a smaller diameter hollow section on a compressor end and a larger diameter hollow section on the turbine end of the shaft. Solid shaft end extend from the hollow section to form a forward solid shaft end to secure the fan rotor disk and an aft solid shaft end to secure the turbine rotor disk. A parabolic shaped transition section joins the forward shaft end to the smaller diameter hollow section, and a conical shaped transition section joins the aft shaft end to the larger diameter hollow section. A conical shaped transition piece joins the two hollow sections together to form an inner rotor shaft that can fit within a minimal space between the compressor rotor disk and the annular combustor assembly of the engine.

Abstract: A process for determining a remaining life of a part, such as an airfoil in a gas turbine engine, comprising the steps of establishing the boundary conditions that act on the part, determining the material properties of the part, creating a 3D finite element model of the part and determining the residual stresses on the part, observing the actual part for at least one crack, and comparing the location of the crack to the residual stresses determined on the model at the crack location. If the residual stress at the crack location passes into the wall of the part beyond a predetermined length, then the part is rejected for further use.

Abstract: A process for determining a remaining life of a part, such as an airfoil in a gas turbine engine, comprising the steps of establishing the boundary conditions that act on the part, determining the material properties of the part, creating a 3D finite element model of the part and determining the residual stresses on the part, observing the actual part for cracks, and comparing the location of the crack to the residual stresses determined on the model at the crack location. If the residual stress at the crack location passes into the wall of the part beyond a predetermined length, then the part is rejected for further use.