#15 – Nick Sills on contra-rotating electric propulsion

On this episode I am speaking to Nick Sills who is the founder of Contra Electric Propulsion Ltd. Nick’s background is in developing underwater propulsion systems for the offshore oil and gas industry. He has designed products ranging from a hydraulically powered excavator for pipeline route trenching, to the world’s biggest deep water excavator. He received a Queen's Award for Technological Achievement for the "Jet Prop" tool, a 5 m diameter propeller that is powered by ejecting high pressure seawater from its propeller blades.

Nick founded his most recent company, Contra Electric Propulsion, to develop a contra-rotating propeller system for the light aircraft market. Contra-rotating propeller systems typically use two propellers mounted in series that spin in opposite directions. The fact that props are spinning in both directions alleviates many of the attitude and control problems when flying aircraft. Contra-rotation has rarely found its way onto modern, gas-powered aircraft because the variable-pitch requirement for efficient operation has made the system overly expensive, complex and maintenance intensive. By changing the power source from fossil fuels to electrons, however, many components of the modern aircraft can be designed differently. With new electric motors it is now possible to build a much simpler, fixed-pitch, contra-rotating propulsion system for light aircraft. As an aerobatic pilot, Nick immediately realised the massive advantages of instantaneous torque delivery and reversible thrust that electric motors can provide. That's why he believes that the next big advance in light aircraft propulsion will be a battery-powered, twin motor, contra-rotating system with fixed-pitch propellers. Since this has now become technically feasible, he is privately building one to prove it.

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