Rolls-Royce is to buy the Siemens business units that are developing electric and hybrid-electric aerospace propulsion.
The Siemens eAircraft business is based in Germany and Hungary and employs around 180 electrical designers and engineers who have been developing all-electric and hybrid electric propulsion technology for the aerospace industry.
The two companies have been working together alongside Airbus to develop the E-Fan X aircraft, a regional aircraft testbed for hybrid-electric propulsion, which is set to make its maiden flight in 2021.
Rob Watson, director of Rolls-Royce Electrical said, “Electrification is set to have as dramatic an impact on aviation as the replacement of piston engines by gas turbines. We are at the dawn of the third era of aviation, which will bring a new class of quieter and cleaner air transport to the skies.”
“This move will accelerate our ambitions in aerospace by adding vital skills and technology to our portfolio. It brings us increased scale and additional expertise as we develop a product range of hybrid power and propulsion systems.”
Paul Stein, Rolls-Royce’s chief technology officer, said, “We believe that pure electric or all-electric propulsion will power smaller aircraft in the foreseeable future, while larger aircraft will rely upon hybrid electric solutions that combine electrification with evolutions of the gas turbine. Additionally, as our group technological portfolio becomes increasingly electrical with the development of hybrid electric trains and microgrids, the capabilities of this world-class team will be a vital part of the future Rolls-Royce.”
The acquisition is expected to complete before the end of this year, following a period of employee consultation.
Rolls-Royce has successfully ground tested a hybrid propulsion system it said is suitable for use across a range of smaller transport platforms including eVTOLs (electric vertical take-off and landing vehicles), general aviation aircraft, and hybrid helicopters. The first experimental test flights of the propulsion system are expected in 2021.
The ground testing has involved a Rolls-Royce M250 gas turbine operating in series hybrid configuration, where the engine operates as a turbo-generator that charges an on-board battery system; parallel hybrid where the aircraft’s thrust is supplied by a combination of the engine and the electrical system; and turbo-electric mode where the engine operates as a pure turbo-generator supplying electric power for thrust and any other power needs on the aircraft.
Last year the company revealed an eVTOL concept. It is also developing an all-electric demonstrator aircraft, as part of the ACCEL (accelerating the electrification of flight) initiative that will attempt to break the world speed record for all-electric flight.
Read more about Rolls-Royce’s approach to the electrification of flight in this Q&A with Rob Watson.