Abstract: A first-stage turbine that is adapted for receiving high energy air directly from a combustion chamber in a gas turbine engine auxiliary power unit includes a disk formed from a first alloy and having an outer surface, and a unitary blade wheel formed from a second alloy that is different than the first alloy. The unitary blade wheel includes an annular member having an inner surface that is joined to the disk, and blades that are integrally formed with the annular member.

Abstract: A first-stage turbine that is adapted for receiving high energy air directly from a combustion chamber in a gas turbine engine auxiliary power unit includes a disk formed from a first alloy and having an outer surface, and a unitary blade wheel formed from a second alloy that is different than the first alloy. The unitary blade wheel includes an annular member having an inner surface that is joined to the disk, and blades that are integrally formed with the annular member.

Abstract: A bearing assembly comprising a centrifugal debris trap for removing contamination debris from lubrication fluid prior to lubrication of the bearing assembly components is provided. The centrifugal debris trap comprises an annular groove on an inner race such that with sufficient centrifugal force, contamination debris in the lubrication oil is forced into the groove and held there. Removal of contamination debris from the lubrication oil prevents damage to bearing balls and races of the bearing assembly, thus reducing bearing fatigue. A method for lubricating bearing assembly components using the bearing assembly of the present invention is also provided.