https://www.cnbc.com/2022/02/22/-airbus-plans-to-test-hydrogen-engine-on-a380-jumbo-jet-to-fly-mid-decade.html

Airbus said it plans to test a hydrogen-powered engine on a modified A380 by the middle of the decade, in hopes of bringing lower-emission fuels to commercial air travel.

on the test plane, which will include a modified version of an engine already in use that will have to handle higher temperatures at which hydrogen burns. Test flights could begin 2026, Airbus said.