The Future of Advanced Air Mobility

Rolls-Royce to Provide Propulsion for Vertical's Improved VA-X4 eVTOL

Rolls-Royce is developing the electric propulsion system for Vertical Aerospace’s VA-X4 eVTOL aircraft. The aero engines group today announced that its Rolls-Royce Electrical division will design the system, which will incorporate 100 kW-class lift and push propulsion units, as well as power distribution and monitoring systems to support operations.

Vertical Aerospace has renamed what was announced last year as the VA-1X as the VA-X4 to reference its ability to carry four passengers. The company now projects increased range and speed of 120 miles and 200 mph—an improvement on the earlier projections of 100 miles and 150 mph. The all-electric design features four sets of coaxial rotors on booms protruding from the rear of the fixed-wing and four sets of five-bladed tilting propellers on the front of the wing.

Around 150 engineers from Rolls-Royce facilities across Hungary, Germany, the U.S., and the UK will support the Vertical Aerospace team, which is based at Bristol in southwest England. In 2019, Rolls-Royce acquired the Germany-based Siemens eAircraft business, and this has formed the bedrock for its ambitions in the advanced air mobility sector.

The company’s development timeline calls for it to roll out the first full-scale prototype in July, and to then begin ground testing in late August, followed by initial tethered flights in September. Initially, the prototype will use an interim propulsion system that will be replaced by the Rolls-Royce system for the version of the aircraft used for the certification process, which Vertical Aerospace aims to complete in 2024. Untethered flights are expected to start in 2022, first in vertical mode, then in forward flight only, and, finally, in transition between these two modes.

In February, Vertical Aerospace selected composites specialist Solvay to develop the main aerostructures for the fuselage and wing of the VA-X4. Belgium-based Solvay is developing a mix of thermoplastic composites, specialty polymers, structural adhesives, and functional films for the aircraft.

Other key contributors to the program include Honeywell, which is providing flight controls, and TE Connectivity, which is supplying electrical cables and connectors.

The selection of Rolls-Royce as a key partner is based in part on the strong ties between the aero engines group and the Vertical Aerospace management team. In May 2020, Rolls-Royce chief engineer Tim Williams moved to Vertical to head up its engineering group. Twelve months earlier, Michael Cervenka also moved from Rolls-Royce to become the start-up’s CEO.

“This exciting opportunity demonstrates our ambitions to be a leading supplier of sustainable complete power systems for the new urban air mobility market, which has the potential to transform the way that people and freight move from city to city,” commented Rob Watson, director of Rolls-Royce Electrical.

Recently, Rolls-Royce announced a partnership with Tecnam to develop an all-electric fixed-wing aircraft called the P-Volt. With a pair of electric motors, this is intended to be a short- and medium-range passenger aircraft.