EMPLOYEE WAS ASSISTING PLANT PERSONNEL IN MOVING A HEAVY ROTOR FROM PLANT PRODUCTION AREA TO A NEARBY STAGING AREA. A LOADER WAS BEING USED TO TRANSPORT ROTOR, AS LOADER WAS LOWERING LOAD THE RIGGING BROKE WHICH SECURED THE ROTOR. THE ROTOR THEN STRUCK A RAILROAD TIE WHICH IN TURN FLIPPED & CAME DOWN ON EMPLOYEE'S RT.FOOT.