Abstract: A radial turbine rotor associated with an engine includes a disk, and a plurality of blades spaced apart about a perimeter of the disk. Each blade includes a forward end, an aft end and a root. The radial turbine rotor includes a plurality of sectors, with each sector coupled to the root of a respective blade of the plurality of blades. Each sector of the plurality of sectors defines a first surface configured to contact a working fluid and a second surface configured to be coupled to the disk, and each sector of the plurality of sectors defines at least one pocket between the first surface and the second surface proximate the forward end that extends toward the aft end. The radial turbine rotor includes a feather seal slot defined between adjacent sectors of the plurality of sectors proximate the first surface.