Rolls-Royce’s hybrid EVTOL concept based around the M250
Quieter, cleaner and potentially disruptive: EVTOLs prepare for take-off. Share
EVTOLs are creating an enormous amount of buzz and Rolls-Royce is well positioned in this emerging space, given its vaunted engineering prowess and commitment to R&D. It has the industry relationships, knows how to certify aircraft, and has experience of hybrid systems having provided them for applications including naval vessels and trains.
Airbus believes the EVTOL market could one day outpace its existing $70bn business. Uber is predicting a fleet of up to 500,000 air taxis, Google founder Larry Page has reportedly invested $100m into a VTOL startup, Kitty Hawk, while three year old start-up Lilium Aviation has so far raised $100m.
Electrification is being hailed as a pillar of the so-called Fourth Industrial Revolution. Along with digitalization, it’s touted as the harbinger of new efficiencies into supply chains and the platform for new public policy. It will radicalize the design of everything from our power grids and roadways to vehicles and urban centres.
The need for a truly revolutionary approach to power couldn’t be starker: by 2030, 1 billion more people will be living on earth than today, with 6 billion annual flyers and an astonishing 5 billion people residing in cities. Electrification has gripped the imagination of companies looking to address this rapidly-changing world. It offers the opportunity for sustainable growth, reduced carbon emissions and a new, fundamental change in the way we power the world around us.
Rolls-Royce’s hybrid EVTOL concept is based around the M250, the engine of choice for roughly 125 types of fixed-wing aircrafts and helicopters. Used in both civil and defence applications, it’s logged 250 million flight hours over the past half-century. By adding an electrical generator, the M250 becomes part of a hybrid-electric propulsion system that can power a 4 to 5 person vehicle capable of travelling at 250mph over a range of 500 miles or more.
The gas turbine generates 300-400kW of electricity while a battery system (making this a series hybrid system) can provide an additional 300-400KW for hover. The aircraft is also capable of executing a conventional take-off or landing. In the longer term, when battery technology improves, we’ll see the emergence of all electric VTOLs for short range missions, but we expect to see hybrids retained for longer range roles.
The first EVTOLs will have the versatility of helicopters. They’re likely to start out relatively small and capable of hauling payloads of a few hundred kilograms. Think about air taxis carrying up to five people, or a cargo carrier that can help speed up delivery times within supply chains. Enabled by distributed electric propulsion, these vehicles will soar over traffic in a way that every commuter dreams about.
As battery technology improves over the years, VTOLs will become more electric and fly for longer ranges and at higher speeds. The drive to go further and faster will see hybrid VTOLs move into the intra-city and inter-city, or inter-city, aviation market. The additional range of hybrid VTOLs, compared with pure electric vehicles, will allow them to fly over less densely populated areas, enabling these platforms to become testbeds for the new emerging autonomous technologies.
