Rolls-Royce runs aero turbine on 100% hydrogen across simulated flight cycle

At the test stand, a modified Rolls-Royce aero gas turbine burned 100 percent hydrogen as engineers took it through simulated take-off, cruise and landing. The result is a demonstration across a simulated flight cycle on hydrogen, not a single engine run at one carefully chosen operating point.

The program began with Rolls-Royce and easyJet in 2022, asking whether hydrogen could work reliably as an aircraft’s operating conditions changed. Tata Consultancy Services joined as an engineering and technology partner in 2024, contributing to fuel systems, engine controls, combustion analysis, testing and data work.

Hydrogen does not behave like conventional jet fuel. Its combustion and storage characteristics require changes to the systems that deliver and burn it. Engineers therefore tested the interaction between fuel delivery, combustion and controls as the simulated flight moved from take-off through cruise to landing, with support from easyJet, NASA, the UK’s Health and Safety Executive and other partners.

The result gives Rolls-Royce data from a complete simulated flight cycle and will inform future propulsion technologies, including UltraFan. If hydrogen propulsion is eventually deployed at scale, it could eliminate in-flight carbon dioxide emissions; aviation currently accounts for about 2-3% of global CO2 emissions.

So what changes in practice? The demonstration shows that a modern aero gas turbine can operate on hydrogen through changing flight conditions. Airlines do not yet have a hydrogen aircraft to fly. Storage, fuel delivery, aircraft integration and infrastructure remain unresolved, and Rolls-Royce says the technology is not ready for commercial service.