Rolls-Royce plans to test whether hydrogen can safely power a small aircraft in ground trials using two of its engines as the UK engineering group steps up research into cutting-edge technologies.
The first trial will be carried out in the UK this year using one of its AE 2100 turboprop engines that powers civil and military aircraft, while the second will test the fuel on a Pearl 15, one of its business jet engines, in the US at a later date.
The move comes as the aviation industry is under pressure to curb harmful emissions. Air traffic volumes and emission levels have rebounded as passengers have returned to the skies following the lifting of Covid-19 travel restrictions.
Aviation consultancy IBA forecasts carbon emissions this year will be 36 per cent higher than 2021 and match pre-pandemic 2019 levels by 2023.
The trials, although not involving flying an aircraft, are part of a new hydrogen demonstration programme launched by Rolls-Royce after research showed there is market potential for hydrogen-powered aircraft.
The research was carried out in partnership with the Fly Zero team aiming to realise zero carbon emissions at the UK’s Aerospace Technology Institute, the body that allocates state funding for innovation in the sector.
The tests will “give us an early feel of some of the challenges of burning hydrogen”, said Alan Newby, director of Aerospace Technology and Future Programmes at Rolls-Royce. A decision on whether to conduct full flight tests will be taken in a year or two.
The FTSE 100 company has until now, at least in public, focused more on the potential for sustainable aviation fuels, SAFs, to help decarbonise aviation rather than hydrogen, which critics warn will be expensive because of infrastructure and investment costs.
Newby said Rolls-Royce was still convinced that in the short term there was no alternative apart from bio-derived SAFs to help the industry reduce emissions.
“In the near term, in terms of decarbonising aviation apart from efficiency solutions, we will continue to need to invest in SAFs . . . We see SAFs as a really key near-term enabler to net zero aviation.”
However, the company has been doing “quite a lot behind the scenes” on hydrogen, said Newby, and the Fly Zero activity “helped us firm up our belief that there would be a role for hydrogen”.
The company, Newby added, wants to be able to offer Airbus, which plans to bring a zero-emissions aircraft into service by 2035, a choice of engines when the European manufacturer comes to deciding whether to launch a commercial plane.
Airbus is working with CFM International, a joint venture between France’s Safran and General Electric of the US, to develop an engine that can run on hydrogen for a test aircraft.
“We don’t know what Airbus plans, but we want to be in a position to give them a choice when it comes to the decision on product launch,” said Newby.
Separately, the company plans to run its UltraFan demonstrator engine on SAFs later this year. The engine offers a 25 per cent fuel efficiency improvement compared with the first generation Trent engine.