It’s nothing new to hear that Rolls-Royce has been working on developing electric propulsion systems that it hopes will power a new generation of emissions-free aircraft that will illuminate the high cost of fossil fuel . The company has partnered with Airbus and Siemens to develop the E-Fan X hybrid plane and with Aston Martin on its Volante Vision VTOL concept. It even showed off its own VTOL concept at the Farnborough International Airshow.
ACCEL (Accelerating the Electrification of Flight)
Rolls-Royce recently revealed plans to build its own all-electric aircraft with financial input by the British government in partnership with YASA and Electroflight. The aircraft developed under the project name ACCEL (Accelerating the Electrification of Flight), the new aircraft will run solely on battery power. The consortium is designing the aircraft to take the title the title of world’s fastest all-electric plane, with planes of reaching speeds in excess of 300 mph.
The current record id held by an Extra 330LE aerobatic plane powered by a propulsion system developed by Munich-based Siemens and reached a speed of 210mph.
Siemens Extra 330LE
The most prohibitive consideration facing electric aircraft manufacturers is that to add range and speed, you need more power, which means adding weight in the form of extra banks of batteries. To help solve this conundrum , the ACCEL will use some of the most power-dense batteries packs ever created. This will allow it to not only allow the propulsion system to deliver a maximum output of just over 1,000 hp, but will also give the aircraft a 200-mile range, long enough to fly from Johannesburg to Nelspruit.
“This plane will be powered by a state-of-the-art electrical system and the most powerful battery ever built for flight,” says Matheu Parr, ACCEL project manager. “In the year ahead, we’re going to demonstrate its abilities in demanding test environments before going for gold in 2020 from a landing strip on the Welsh coastline.”
The 6,000-cell ACCEL battery pack is the most energy-dense battery pack ever developed for flight and provides – through a 90-percent efficient powertrain – 750 volts to three lightweight, high power YASA e-motors. The aircraft’s propeller will operate at lower number of revolutions per minute (RPM) than a conventionally powered aircraft; however, it will deliver a stable and relatively quiet 1000 horsepower.
“We’re monitoring more than 20,000 data points per second, measuring battery voltage, temperature, and overall health of the powertrain, which is responsible for powering the propellers and generating thrust. We’ve already drawn a series of insights from the unique design and integration challenges,” says Parr. “And we’re gaining the know-how to not only pioneer the field of electric-powered, zero-emissions aviation – but to lead it. At this point, our confidence is sky high.”
The aircraft, 23-foot long, single seat, single prop, low wing racing plane with a 24-foot wingspan, is small and sporty, with the cockpit positioned towards the rear of the plane behind a long nose that that gives it a shape reminiscent of a Competition Aerobatic aircraft. However, this design serves a practical purpose as well, as the long nose section houses the banks of battery packs needed to power the plane.
While this particular design will probably never be made into a production model, it does serve as a great benchmark for the progress that has been made in the field of electric aircraft within a few short years. Moreover, the team plans to build, test, and commercialize the aircraft in a market that does not yet exist all within a 24-month span – a relative blink of the eye in the world of aircraft development. They will be using an agile approach with a unique collaborative model to test new ideas and work through energy storage and performance challenges at a rapid pace.
Rolls-Royce anticipates that the ACCEL will be completed by 2020, when it is also expected to attempt its record-setting speed run.
