where electric motors can complement conventional engines to reduce fuel consumption and emissions. Rotary-wing aircraft, such as helicopters, are also embracing electric propulsion systems ...

As far as the engines are concerned, the company settled on the PW2040 made by Pratt & Whitney. It's the same powerplant that powers the Boeing 757 aircraft (including the military C-32A version ...

I have already written about LiquidPiston and its XTS-210, but Avadi's idea is even more striking: it is a reciprocating engine that works as a rotary. Imagine an ICE with a single piston.