The Rolls-Royce ACCEL (Accelerating the Electrification of Flight) is an electric aircraft demonstrator developed by Rolls-Royce plc.

Role Electric aircraft testbed
National origin United Kingdom
Manufacturer Rolls-Royce plc
First flight 15 September 2021
Status Flight testing[1]
Developed from Sharp Nemesis NXT[2]

Development edit

Rolls-Royce developed the ACCEL as a racing aircraft to gain the all-electric air speed record, targeting over 260 kn (480 km/h).[3] The existing electric aircraft record at that time was 182 kn (337 km/h), set in 2017 by a Siemens powered Extra 330.[2]

Designed at Gloucestershire Airport, the project is partly funded by the UK government and involves partners such as electric motor and controller manufacturer YASA Limited and aviation start-up Electroflight.[3]

The team aimed to reach the 1931 Schneider Trophy speed, which was won by a R-R-powered Supermarine S.6B, reaching 298 kn (552 km/h).[2]

On 15 September 2021, Rolls-Royce announced the aircraft, named Spirit of Innovation, had successfully completed its first flight, flying from MoD Boscombe Down for fifteen minutes.[4] It subsequently reached a top speed of 336 kn (622 km/h), and sustained 300 kn (560 km/h) over 3 km, 287 kn (532 km/h) over 15 km, and was able to climb to 3,000 m (9,800 ft) in 3min 22s.[5] The speeds achieved were accepted as world records for electric aircraft by the Fédération Aéronautique Internationale in January 2022.[6]

Design edit

The 7.3 m (24 ft) span aircraft is powered by three axial flux motors[7] with a high power density driving a single three-blade propeller spinning at 2,400 RPM, designed and manufactured by YASA.[3] The 750 volt, 216 kWh battery has 6,480 cells, with cork insulation and active cooling. Battery output power will be 500 hp (373 kW) continuous, reaching 750 kW (1,010 hp) at maximum power..[8] It is designed to have the highest energy density for an aircraft, and should allow a 170 nmi (310 km) range.[3]

The aircraft is derived from the carbon fibre Sharp Nemesis NXT racer, which has a cruising speed of 282 kn (522 km/h) with a 350 hp (261 kW) piston engine, but can reach 355 kn (657 km/h) with a highly tuned engine. The maximum take-off weight of the NXT is 1,200 kg. Rolls-Royce intend the battery, motors and control equipment in a production system to weigh the same as the regular engine and fuel tank in a conventional aircraft,[2] but the battery pack alone in the Spirit of Innovation currently weighs 1350 kg.[9]

References edit

  1. ^ "Rolls-Royce all-electric aircraft breaks world records". BBC News. 21 January 2022.
  2. ^ a b c d Michael Gubisch (9 January 2019). "Rolls-Royce aims to break speed record with electric single-seater". Flightglobal.
  3. ^ a b c d "Introducing ACCEL". Rolls-Royce Plc. 2 January 2019.
  4. ^ "Rolls-Royce's all-electric 'Spirit of Innovation' takes to the skies for the first time". Rolls-Royce. 15 September 2021.
  5. ^ Dominic Perry (19 November 2021). "Rolls-Royce waits on ratification for Spirit of Innovation speed records". Flightglobal.
  6. ^ O'Connor, Kate (20 January 2022). "Rolls-Royce Electric Aircraft Becomes World's Fastest". AVweb. Archived from the original on 21 January 2022. Retrieved 21 January 2022.
  7. ^ "Electric Planes Are FINALLY Here and They're Breaking Records!". YouTube.
  8. ^ "Spirit of Innovation Factsheet" (PDF). Rolls-Royce.
  9. ^ Prachi Patel (28 January 2020). "The Battery Design Smarts Behind Rolls Royce's Ultrafast Electric Airplane". IEEE Spectrum.

External links edit