Airbus, Rolls-Royce, Siemens partner to launch E-Fan X

The E-Fan X hybrid-electric technology demonstrator is anticipated to fly in 2020 following a comprehensive ground test campaign, provisionally on a BAe 146 flying testbed, with one of the aircraft’s four gas turbine engines replaced by a two-megawatt electric motor. Provisions will be made to replace a second gas turbine with an electric motor once system maturity has been proven.

Said Paul Eremenko, Airbus’ chief technology officer: “We see hybrid-electric propulsion as a compelling technology for the future of aviation.”

The E-Fan X demonstrator will explore the challenges of high-power propulsion systems, such as thermal effects, electric thrust management, altitude and dynamic effects on electric systems and electromagnetic compatibility issues. The objective is to push and mature the technology, performance, safety and reliability enabling quick progress on the hybrid electric technology. The programme also aims at establishing the requirements for future certification of electrically powered aircraft while training a new generation of designers and engineers to bring hybrid-electric commercial aircraft one step closer to reality.

Areas of expertise

As part of the E-Fan X programme, Airbus, Rolls-Royce, and Siemens will each contribute with their extensive experience and know-how in their respective fields of expertise:

• Airbus will be responsible for overall integration as well as the control architecture of the hybrid-electric propulsion system and batteries, and its integration with flight controls.
• Rolls-Royce will be responsible for the turbo-shaft engine, two-megawatt generator, and power electronics. Along with Airbus, Rolls-Royce will also work on the fan adaptation to the existing nacelle and the Siemens electric motor.
• Siemens will deliver the two-megawatt electric motors and their power electronic control unit, as well as the inverter, DC/DC converter, and power distribution system. This comes on top of the E-Aircraft Systems House collaboration between Airbus and Siemens, launched in 2016, which aims at development and maturation of various electric propulsion system components and their terrestrial demonstration across various power classes.

Paul Stein, Rolls-Royce's chief technology officer, said: “The E-Fan X enables us to build on our wealth of electrical expertise to revolutionise flight and welcome in the third generation of aviation. This is an exciting time for us as this technological advancement will result in Rolls-Royce creating the world’s most powerful flying generator.

“Siemens has been driving innovation in core technology fields at full speed,” said Roland Busch, chief technology officer of Siemens. “In April 2016 we opened a new chapter in electric-mobility with the collaboration with Airbus. Building up electric propulsion for aircraft, we are creating new perspectives for our company and also for our customers and society. With the E-Fan X partnership, we now take the next step to demonstrate the technology in the air.”

Top challenges

Among the top challenges for today’s aviation sector is to move towards a means of transport with improved environmental performance, that is more efficient and less reliant on fossil fuels. The partners are committed to meeting the EU technical environmental goals of the European Commission’s Flightpath 2050 Vision for Aviation (reduction of CO2 by 60%, reduction of NOx by 90% and noise reduction by 75%).

These cannot be achieved with the technologies existing today. Therefore, Airbus, Rolls-Royce and Siemens are investing in and focusing research work in different technology areas including electrification. Electric and hybrid-electric propulsion are seen today as among the most promising technologies for addressing these challenges.