A disengagement assembly for disengaging a generator from an engine or gear box may include an inner ball screw having helical threading on an outer surface thereof and surrounding and operatively engaged to a rotating generator drive shaft to cause rotation of the inner ball screw, the inner ball screw may have interlockable teeth engaged to corresponding teeth of the gear box drive shaft. An outer ball screw may surround and may normally rotate with the inner ball screw. A helical ball track may be formed between the inner and outer ball screws. An eddy current brake may slow or stop rotation of the outer ball screw so that the inner ball screw may rotate relative to the outer ball screw and slide axially toward a lock thereby disengaging the generator from the engine.