Joby-backed H2Fly achieves progress in hydrogen technology

Avatar for eVTOLBy eVTOL | July 20, 2022

Estimated reading time 3 minutes, 15 seconds.

Josef Kallo, co-founder and CEO of H2Fly, believes that liquid hydrogen has significant advantages over alternative pressurized hydrogen gas — “not least because it becomes possible to carry a far greater quantity on board an aircraft,” he said.

Joby H2FLY
H2Fly’s HY4 hydrogen-powered aircraft takes to the skies during a test flight. The company’s aircraft, which is currently operated using pressurized gaseous hydrogen, will be modified to receive a new liquid hydrogen tank, doubling its range capability. H2Fly Image

“An aircraft that uses liquid hydrogen has the potential to transform the way we travel between cities, regions and countries, delivering true zero-emissions flight on medium- and long-haul flights,” Kallo said.  

H2Fly has dedicated the last 10 years to researching, testing and refining its HY4 aircraft, which first took flight in 2016. The company believes liquid hydrogen could significantly increase the range of hydrogen-powered aircraft.

For eVTOL companies like Joby Aviation, liquid hydrogen could offer an alternative clean energy source to its current battery technology, opening up new markets for regional air mobility.

Joby sees potential in the technology, reportedly acquiring the German startup in April 2021. Any progress in hydrogen technology from H2Fly is good news for Joby.

During the Farnborough International Airshow, the hydrogen-electric aviation company said its HY4 aircraft, which is currently operated using pressurized gaseous hydrogen, will receive a new liquid hydrogen tank in a few weeks.

The modification is expected to allow the aircraft to double its range capability, and marks the first time the H2Fly team has handled liquid hydrogen on board. Once the aircraft is fitted with a new liquid hydrogen tank, it will be expected to undergo what the company calls a rigorous program of ground testing in early 2023.

Earlier this year, H2Fly completed a cross-country 77-mile (124-kilometer) flight from Stuttgart to Friedrichshafen, Germany. It was the first time a hydrogen-powered passenger plane has flown between two commercial airports.

The company also achieved what it believes to be a world record for the highest altitude flown by a hydrogen aircraft, flying at 7,230 feet (2,204 meters).

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  1. A ruptured liquid hydrogen tank could be interesting — shades of the problems with C stoff and T stoff in the Me163 (dissolved pilots) wasserstoff might be best kept well away like in the centre pod of the twin Taurus .. Would not boil off over extended periods on the ground be an issue and embrittlement of metallic tanks or cold shattering of plastic ones ? In any case the energy and emissions to create LH2 renders it far from zero emissions like battery power as well.

    1. Yes unless green hydrogen is used it would not be emission free except when flying. However unless batteries are charged with only solar or wind generation,they are not emission free either. The advantage hydrogen would have over batteries is weight. Need a lot of batteries to keep an airplane flying and hydrogen could be refueled faster then charging batteries.

  2. Hydrogen is great but a pressurized system is dangeous im sure with a community of engineers and researchers surely we can come up with an on demand system and if we cant then go back to gas and vaporize it to exceed current mpg for extreme effiecient system,you researchers are a little slow!!!

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