Transmission for Varying Aircraft Power Between Electric and Mechanical Outputs

A method for splitting power output from an engine between a first electric machine and a propulsion mechanism comprising:

• controlling, in a first mode of operation, the first electric machine to generate electricity using most or all mechanical power output from the engine, wherein the first mode further comprises controlling a gearset using a second electric machine such that little or none of the mechanical power output from the engine is directed to the propulsion mechanism;
• controlling, in a second mode of operation using the first electric machine and the second electric machine, the first electric machine to generate electricity using a first substantial portion of the mechanical power output from the engine and the gearset to cause a second substantial portion of the mechanical power output from the engine to be output to the propulsion mechanism;
• and
• controlling, in a third mode of operation, the first electric machine to generate very little or no electricity from the mechanical power output from the engine, wherein the third mode further comprises controlling the gearset using the second electric machine such that most or all of the mechanical power output from the engine is directed to the propulsion mechanism.