Rolls-Royce pushed a 100% hydrogen jet engine to full power, and the hardest part of clean flight may be hiding inside the engine

This was not a one-off experiment built for a headline. The hydrogen work followed a staged path, beginning in 2022 when easyJet and Rolls-Royce ran a modern AE2100 aircraft engine on 100% green ...
American Machinist

Rolls Proposes New Narrow-Body Jet Engine

Rolls-Royce initiated the UltraFan program more than 10 years ago, and the demonstrator engine is assembled and undergoing testing in Derby, England, at full power and running on Sustainable Aviation ...