"The goal of ‘RETAX’ is to explore intrinsically safe and efficient solutions for mid-size rotorcraft autonomoustaxiing on ground, minimizing the overall weight of the system, based on an electrically-powered motorizedwheel integrated with the landing gear. Subsequently to select the most promising solution and develop it intoa technical demonstrator to be tested and verified.The former experience of Michelin in electric-drive solutions for motorized cars, busses and aircraft will beused and translated into a rotorcraft electric taxiing system. A high level of integration and performance willhave to be reached in order to be able to achieve an optimal solution. A key success factor will be the controlof the complete chain, from the power electronic to the wheel, through electrical motor and gearbox in order toreach the global optimization customized for this specific application.After a preliminary study to define the optimum feasible concept and architecture for the motorized wheel andpower electronics, including the voltage level choice (28 Vdc or 270 Vdc), a detailed analysis and simulation ofthe intended solution will be performed.A real demonstrator of the electric-drive system will be designed, engineered and built to physically test andprove the intended performance, the fulfilment of all requirements and also to calibrate the simulation models.The protections for high-voltage human safety (270 Vdc) will be included in the demonstrator, if high voltage isused. An extrapolation study towards larger size rotorcraft will be performed.This feasibility demonstration of electrically driven rotorcraft ground taxiing in accordance with Clean Skyelectrification objectives will be a significant step towards greener rotorcraft operations, bringing thistechnology closer to the market, and creating European competitive advantage."