Several companies are now planning low-emission hybrid eVTOLs, and Rolls-Royce has stepped up to develop a turbogenerator specifically designed to act as a compact, efficient range-extender for this emerging class of aircraft.

Most of the benefits of battery-only VTOLs will remain; the powertrains will remain fully electric and they'll continue to carry decent-sized battery packs, so they can be just as quiet on takeoff and landing, and shorter missions can be flown emissions-free, without ever switching the generator on. Indeed, even flying out toward their maximum range, these hybrid eVTOLs should be able to considerably reduce emissions as compared to ICE-powered planes or helicopters.