Gas turbine engine having a turbine rotor with torque transfer and balance features

A rotor disc assembly, comprising:

• a first extension member axially extending from a disc body disposed about an axis;
• a first finger axially extending from the first extension member, the first finger defining a notch;
• and
• a first balance ring at least partially received within the notch, the first balance ring having a first balance ring body extending between a first balance ring first end and a first balance ring second end, the first balance ring first end having a first tab extending radially inward towards the axis and the first balance ring second end having a second tab extending radially inward towards the axis.

A rotor disc assembly, comprising:

• a rotor disc having:
• a first extension member axially extending from a disc body disposed about an axis;
• a first finger extending axially from the first extension member;
• a second finger circumferentially spaced apart from the first finger, the second finger extending axially from the first extension member, each of the first finger and the second finger having a first portion and a second portion extending radially from a distal end of the first portion;
• and
• a minidisc operatively connected to the rotor disc having:
• an interlocking finger radially extending from a minidisc body and disposed between the first finger and the second finger, wherein the interlocking finger, the first portion, and the second portion define a ring groove.