Abstract: A system for transferring mechanical torque variably between a plurality of rotating machines in a turbofan engine. Two devices are used, where the first device relies upon magnetic properties of a planetary magnetic gearbox to couple the magnetic machines. The second device is used to variably control the torque transfer between the magnetic machines. The system couples rotating shafts rotating at differing speeds within a turbofan engine for controllably transferring power. To transfer power in the system, a fixed gear ratio is obtained by coupling the relatively high- and low-speed engine shafts to an epicyclic magnetic gearbox.