After three years of collaboration Rolls-Royce and Airbus have decided the time is right to end development of the E-Fan X demonstrator.

Paul Stein, chief technology officer at Rolls-Royce, made the announcement: "One of the great endeavours in creating new, disruptive technologies such as electrification has been our E-Fan X programme 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. What has been particularly encouraging has been the amount of industry interest and support for this programme, and I know everyone at Rolls-Royce and Airbus has been truly grateful for that.

"As with all such leading-edge programmes, 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 programme to ensure that all industry safety requirements are met."

The collaborators have agreed that the actual E-Fan X programme will now conclude, but Rolls-Royce says that its power generation system ground testing will complete, allowing the company to demonstrate the technology and capture all the lessons. "This will involve integrating our generator, now well advanced on test in Trondheim, Norway, with our already-proven control systems and thermal management systems which have been developed at Derby and Indianapolis respectively," says Stein.

Amongst the achievements from E-Fan X has been the generator – about the same size as a beer keg – but producing someg 2.5 MW, enough power to supply 2,500 homes.

"We will be going through a short period of re-planning due to this decision to make sure we properly capture all the lessons, knowledge and associated intellectual property," says Stein. "The work from this and other projects that we are actively involved in will ensure that we remain a pioneer of electrification, ready to power the more sustainable aircraft of the future."