Airbus and Rolls-Royce have ended a joint venture to produce a hybrid-electric airliner testbed that could have paved the way for electric aircraft of the future.
Airbus CTO Grazia Vittadini said in a statement late last week that "we need to re-focus all of our efforts on technology 'bricks' that will take us" to a low-CO2-emissions future.
"As with all ground-breaking R&T projects, it's our duty to constantly evaluate and reprioritise them to ensure alignment with our ambitions. These decisions are not always easy," she continued.
The E-Fan X project, announced in 2017, was supposed to use an elderly BAe-146 airliner as a testbed for mounting an experimental electric engine. One of the four jet engines on the wing (number 3; inner right) was due to be replaced by an electric motor powered by an AE2100 gas turbine in the fuselage, in turn driving a 2.5MW generator.
Once the single motor had been proved in test flights, the intent was to replace a second jet engine with an electric motor.
Reading between the lines, 2017's declaration that the project would be airborne by this year, coupled with both Vittadini and Rolls-Royce's most recent statements that it was due to fly in 2021, perhaps sheds some more light on what happened.
Industrial electrickery conglomerate Siemens left the project under a cloud in 2019, with Germany's Die Welt reporting a spokesman saying at the time that "the agreed goals were achieved one year faster than expected, so that there is now an earlier separation". A rumoured investment of hundreds of millions of pounds over five years seemed to have come to a halt.
Rolls-Royce chief techie Paul Stein said in a statement last week: "Although our programme with Airbus concludes, we are planning that our power generation system ground testing will complete, allowing us to demonstrate the technology and capture all the lessons."
The British engine maker's CTO enthused over the fruits of the project to date, saying: "Amongst the many great achievements from E-Fan X has been the generator – about the same size as a beer keg – but producing a staggering 2.5MW. That's enough power to supply 2,500 homes and fully represents the pioneering spirit on this project."
Strangely, in March The Engineer magazine reckoned that the Cranfield, Bedfordshire-based BAe-146 was ready for initial, non-electric, test flights this year. Although the BAe-146 can fly on three of its four conventional jet engines, Cranfield's runway isn't long enough to do that safely.
Bob Gilfillan, chief engineer for E-Fan X at BAE Systems Air, told the magazine: "The aircraft has been under our control since October. There were some test flights conducted then and at the end of February to baseline the performance, so that after it's modified we can assess the impact of the hybrid-electric system accurately."
BAE Systems is the original designer and manufacturer of the BAe-146 in its 1980s corporate guise of British Aerospace. The testbed, registered G-WEFX, was expected to be flown to Airbus's French HQ at Toulouse for the electric trials.
With the COVID-19 pandemic having grounded most of the world's aviation industry and begun ravaging economies across the planet, it is inevitable that R&D spending is being tweaked by cautious companies. ®