LONDON–Rolls-Royce’s £6 million ($8.17 million) Spirit of Innovation electric aircraft has secured the world electric aircraft speed record following verification by the Fédération Aéronautique Internationale (FAI). 

The highly modified Nemesis NXT racing aircraft, also known as Accel, recorded a speed of 555.9 km/hr. (345.4 mph) over 3 km during a Nov. 16 flight. That broke the previous record set by a Siemens’ eAircraft division modified Extra 330LE aircraft of 213.04 km/hr. (132 mph) in March 2017. FAI also confirmed a record speed of 532.1km/hr. (330 mph) over a 15-km course. 

The aero-engine manufacturer also said the aircraft managed to achieve a maximum speed of 623 km/hr. (387.4 mph) during flights performed at Boscombe Down, England, between September and November. This makes the aircraft the world’s fastest all-electric vehicle. Rolls-Royce chief test pilot Phill O’Dell flew the Spirit of Innovation on the 3-km run, while pilot Steve Jones from project partner Electroflight undertook the 15-km record run. 

“Achieving the all-electric world-speed record is a fantastic achievement for the Accel team and Rolls-Royce,” Rolls-Royce CEO Warren East said. “The advanced battery and propulsion technology developed for this program has exciting applications for the advanced air mobility [AAM] market ... and this is another milestone that will help make ‘jet zero’ a reality and supports our ambitions to deliver the technology breakthroughs society needs to decarbonize transport across air, land and sea.” 

The aircraft was modified in conjunction with Gloucestershire-based electric aircraft firm Electroflight and UK electric motor developer YASA.  

At the heart of the modifications is a 450-kg, 6,000-cell lithium-ion direct current battery. It is designed for speed rather than endurance and developed from batteries that drive power tools, enabling the cells to be rapidly discharged. Key to the battery has been the repackaging of the cells to try to deliver around 155 watt-hours per kilogram, while the battery case has been designed to contain a potential thermal runaway situation.   

The battery ran a trio of YASA-developed, galvanically isolated 750-volt, 133-kW motors that give the aircraft a power output of 400 kW, the equivalent of nearly 550 hp.  

Half of the £6 million spent on the project was provided by the aero-engine manufacturer. The other half came from the UK’s Aerospace Technology Institute (ATI) in partnership with the UK Department for Business, Energy and Industrial Strategy. 

“Rolls-Royce’s revolutionary Spirit of Innovation aircraft is yet more proof of the UK’s enviable credentials when it comes to innovation,” UK Business Secretary Kwasi Kwarteng said. “This record will show the potential of electric flight and help to unlock the technologies that could make it part of everyday life.”

In addition to the speed records, Rolls-Royce is also claiming to have secured the fastest time to climb to 3,000 m by an electric aircraft, 202 sec. That breaks the current record by 60 sec. But this still needs to be verified by FAI, the company said.