H2Fly Prepares To Integrate Liquefied Hydrogen Tank into HY4 Test Aircraft
The German company was acquired by eVTOL aircraft developer Joby Aviation, which has yet to say whether it intends to use the hydrogen propulsion systems for its own vehicles.
H2Fly is close to converting its HY4 demonstrator aircraft to run on liquefied hydrogen. (Image: H2Fly)

Hydrogen fuel cell developer H2Fly is about to modify its HY4 aircraft with a new liquefied hydrogen tank that will double its range. The technology demonstrator aircraft started test flights in 2020 using pressurized gaseous hydrogen, and the Germany-based company aims to start the next phase of ground trials for the system in early 2023.

H2Fly believes that its sixth-generation powertrain could be used for 40-seat airliners on flights of up to around 2,000 km (1,250 miles). It intends to produce the first commercial aircraft to be powered by liquid hydrogen.

The company is already working with Munich-based Deutsche Aircraft and has agreed to collaborate on plans to convert a 1990s-vintage Dornier 328 regional airliner to hydrogen power. The partners hope to be ready to start flight testing the former twin turboprop in 2025 as part of a timeline that H2Fly founder and CEO Josef Kallo told FutureFlight could lead to an aircraft being certified under EASA’s Part CS-25 rules (equivalent to FAA's Part 25) in about seven to eight years.

Earlier this year, the HY4 made a cross-country flight of 77 miles between Stuttgart and Friedrichshafen in Germany. It has also set what the company believes is a world altitude record for a hydrogen-powered aircraft by cruising at 7,230 feet.

Last year, U.S.-based eVTOL aircraft developer Joby Aviation acquired H2Fly in a deal that was not announced at the time. Joby has not commented on its intentions for the company.