Airbus and Rolls Royce jointly have decided to end the E-Fan X demonstrator program. (Earlier post.) Launched in 2017, the E-Fan X project sought to develop a near-term hybrid-electric flight demonstrator for commercial aircraft.

… decarbonizing the aviation industry is no small feat. To achieve this, we need to re-focus all of our efforts on technology bricks that will take us there. It’s for this reason that Airbus and Rolls Royce have jointly decided to bring the E-Fan X demonstrator to an end. As with all ground-breaking R&T projects, it’s our duty to constantly evaluate and reprioritize them to ensure alignment with our ambitions. These decisions are not always easy. But they’re undoubtedly necessary to stay the course.

When we launched the E-Fan X project in 2017, we set out with the ambition to push the limits by testing disruptive technologies in a game-changing approach to future aircraft. And we did just that: E-Fan X has shattered pre-conceived notions of what is possible in future flight. This helped us to pave the way for an industry-wide decarbonization movement of which we’re proud to take the lead.

—Grazia Vittadini, Airbus Chief Technology Officer

Vittadini said that the E-Fan X project provided insights for the future, including:

1. Series-hybrid-electric propulsion. Hybrid architectures, high-voltage systems and batteries are indispensable technology bricks for several other demonstrator projects across the wider Airbus R&T portfolio to diversify power sources. Airbus will continue to develop and mature them at its E-Aircraft System Test House.

2. New pathways for CO₂ reduction. Exploring the possibilities—and limitations of—series-hybrid-electric propulsion also opened up inquiry into new technology pathways, hydrogen being one of them.

3. Future certification and regulatory acceptance. With the research partnerships on hybrid-electric and hydrogen airport infrastructure and operations, Airbus has laid a foundation for the future industry-wide adoption and regulatory acceptance of alternative-propulsion commercial aircraft.

We’ve taken great steps at Rolls-Royce with our three-pillar sustainability approach of developing the gas turbine to even greater efficiency, supporting the introduction of Sustainable Aviation Fuel and creating new, disruptive technologies such as electrification.

One of the great endeavors in the latter category has been our E-Fan X program in partnership with Airbus. From our side, this has involved creating a hybrid-electric power generation system at a scale never previously seen in our industry, comprised of an embedded AE2100 gas turbine driving a 2.5MW generator and 3000V power electronics and an electric propulsion unit.

… As with all such leading-edge programs, we constantly evaluate the best way forward and it has become clear to both parties that the actual requirement to carry out a test flight with all the elements integrated is not critical at this time. As an aircraft, E-Fan X was always designed to be a demonstrator only and never for actual use as a product in service.

From the Rolls-Royce perspective, our power generation system can and will be integrated into any future aircraft that is developed requiring a hybrid-electric propulsion system, including a comprehensive flight-test program to ensure that all industry safety requirements are met.

—Paul Stein, Rolls-Royce, Chief Technology Officer