Rolls-Royce has reached a pivotal milestone in its hydrogen research project, marking a world industry first. The implications of this achievement extend far beyond the confines of the laboratory, potentially reshaping the future of flight technology.
Rolls-Royce, in partnership with easyJet, is committed to leading the charge in developing hydrogen combustion engine technology capable of powering a variety of aircraft, including those in the narrow-body market segment. Their vision is to make hydrogen-powered flight a reality by the mid-2030s.
Collaborating with esteemed institutions like Loughborough University in the UK and the German Aerospace Centre Deutsches Zentrum für Luft-und Raumfahrt (DLR), Rolls-Royce has reached a critical juncture in its journey towards enabling hydrogen as a viable aviation fuel. Tests on a full annular combustor of a Pearl 700 engine at DLR running on 100% hydrogen have proven the fuel can be combusted at conditions that represent maximum take-off thrust.
Hydrogen testing at DLR. Photo: Rolls-Royce
A key factor in this achievement was the successful design of advanced fuel spray nozzles capable of controlling the combustion process. This involved overcoming significant engineering challenges as hydrogen burns far hotter and more rapidly than kerosene. The new nozzles were engineered to control the flame position using a system that progressively mixes air with hydrogen, thereby managing the fuel’s reactivity. Rolls-Royce announced that both combustor operability and emissions met expectations.
Last year, easyJet and Rolls-Royce set another world first by successfully running a modern aero engine, specifically an AE2100, on green hydrogen at Boscombe Down, UK.
With these recent tests, the combustion element of the hydrogen programme is now well-understood, while ongoing efforts are directed towards developing systems for the efficient delivery of hydrogen to the engine and seamlessly integrating these systems.
Grazia Vittadini, Chief Technology Officer at Rolls-Royce, said, “This is an incredible achievement in a short span. Controlling the combustion process is one of the key technology challenges the industry faces in making hydrogen a viable aviation fuel of the future. We have accomplished this milestone, and it fuels our eagerness to continue advancing.”
Johan Lundgren, CEO of easyJet, echoed the sentiment, stating, “We firmly believe that hydrogen represents the future of short-haul aviation, and the success of these tests, coupled with ongoing progress, brings this future ever closer. We remain optimistic that hydrogen will play a pivotal role in helping us achieve the ambitious goals outlined in our net-zero roadmap.”
The technologies tested at Loughborough and DLR will now be integrated with insights gained from the Boscombe Down tests, as Rolls-Royce and easyJet prepare for the next stage—a comprehensive ground test using gaseous hydrogen on a Pearl engine. This will set the stage for a full ground test on a Pearl engine using liquid hydrogen.