H2FLY Achieves Historic Milestone: Successful Maiden Flight of Liquid Hydrogen-Fueled Aircraft

The aviation world witnessed a groundbreaking achievement as H2FLY, headquartered in Stuttgart, Germany, accomplished the first-ever piloted flight of an electric aircraft powered by liquid hydrogen.

This groundbreaking event unfolded in Maribor, Slovenia, where the hydrogen-electric HY4 demonstrator aircraft completed four test flights, including a remarkable journey lasting over three hours.

The HY4 demonstrator aircraft boasts a hydrogen-electric fuel cell propulsion system and utilizes cryogenically stored liquid hydrogen for power, marking a pivotal advancement in hydrogen fuel storage technology.

Unlike traditional pressurized gaseous hydrogen storage, which comes with bulkier tanks and limitations, the use of cryogenic liquid hydrogen significantly reduces tank weight and volume. This innovation translates into an extended aircraft range and enhanced capacity for additional payload.

Test results from H2FLY's experimental flights reveal that the adoption of liquid hydrogen, as opposed to gaseous hydrogen, will effectively double the HY4 aircraft's maximum range. This remarkable development increases the range from 750 kilometers (466 miles) to an impressive 1,500 kilometers (932 miles).

Professor Josef Kallo, a co-founder of H2FLY and a featured speaker at the upcoming Aerospace Test & Development show, commented, "This achievement marks a watershed moment in the use of hydrogen to power aircraft. Together with our partners, we have demonstrated the viability of liquid hydrogen to support medium and long-range emissions-free flight."

Kallos went on to say, "We are now looking ahead to scaling up our technology for regional aircraft and other applications, beginning the critical mission of decarbonizing commercial aviation."

This monumental success also signifies a significant milestone for Project HEAVEN (High power density FC System for Aerial Passenger Vehicle), an EU-funded research program that H2FLY leads. Project HEAVEN aims to showcase the feasibility of implementing liquid cryogenic hydrogen in aircraft.

HEAVEN's collaborative partners include Air Liquide, an esteemed gas company, electric aircraft manufacturer Pipistrel, the German Aerospace Center (DLR), EKPO Fuel Cell Technologies, and the Spanish non-profit Fundación Ayesa.

Pierre Crespi, Innovation Director at Air Liquide Advanced Technologies, expressed pride in their contribution, saying, "Air Liquide is proud to have designed, manufactured, and integrated, together with H2FLY, the liquid hydrogen tank that enabled the HY4 aircraft to soar."

Crespi also emphasized the significance of this achievement, noting that liquid hydrogen offers great potential for aviation. Liquid hydrogen can be effectively stored onboard and transported, making it a key player in the transition to cleaner energy solutions.

Having concluded the successful flight testing as part of project HEAVEN, H2FLY's next focus will be on navigating the testing and certification process for commercialization. Earlier this year, the company announced the development of its H2F-175 fuel cell systems, designed to provide a full power range at flight altitudes of up to 27,000 feet. This development marks a crucial step toward real-world commercial applications.

Additionally, H2FLY has plans to establish its Hydrogen Aviation Center at Stuttgart Airport next year. Co-funded by the regional ministry of transport, this center will provide facilities for fuel cell aircraft integration and liquid hydrogen infrastructure.

H2FLY's journey began with five engineers from the German Aerospace Center in Stuttgart and the University of Ulm, dedicated to delivering the first certified, fully hydrogen-electric aircraft powertrain to the market. In 2021, the company was acquired by Joby Aviation, a California-based developer of electric vertical takeoff and landing (VTOL) aircraft.

This achievement by H2FLY represents a significant stride toward a more sustainable and efficient future for aviation, highlighting the growing potential of hydrogen as a green aviation fuel.