Airbus has announced plans to test a hydrogen-fuelled aircraft by the middle of this decade, with a view to launching zero-emissions flights by 2035.
The technology will be tested on a modified A380 jetliner, in a newly-signed partnership with CFM International.
Hydrogen fuel, touted by some as the fuel of the future, is seen as a potential solution for the deeply polluting aviation and shipping industries in a net-zero world: hydrogen burns cleanly, producing just energy and water vapour.
But while engineers have promoted hydrogen as a possible transport fuel since at least the 1920s, real-world technologies are still in their infancy, thanks to the destructive dominance of fossil fuels over the last century.