The Future of Advanced Air Mobility

H2Fly’s HY4 Demonstrator Sets Altitude Record for Hydrogen-Electric Aircraft

Stuttgart, Germany-based H2Fly has set what it believes represents a new world altitude record for a hydrogen-powered passenger aircraft, the developer of hydrogen fuel cell applications for aviation reported on April 19. Besides flying its HY4 demonstrator on April 13 to an altitude of 7,230 feet, H2Fly took the aircraft on a 77-mile journey between Stuttgart and Friedrichshafen on April 12, marking the first time anyone has piloted a hydrogen-electric passenger aircraft between two major airports, the company added.  

The aircraft flew the mission to Friedrichshafen to participate in the Aero Friedrichshafen airshow, scheduled to take place from April 27 to April 30. The appearance will mark the first time the company has displayed the HY4 to the general public. Testing of the aircraft has taken place exclusively in an area around Stuttgart Airport, which serves as a long-term partner of H2Fly and plays a key role in supporting the company with its infrastructure.

“Particularly in view of the numerous projects on sustainable mobility in aviation, I see great opportunities for the Friedrichshafen site to create the framework conditions for innovative aviation companies and to attract them here,” said Friedrichshafen Airport managing director Claus-Dieter Wehr.

The four-seat HY4 has demonstrated the applicability of hydrogen-electric propulsion in several flight campaigns during which it executed more than 90 takeoffs. It also serves as a test platform to further develop the propulsion system and lay the foundation for development work on a hydrogen-electric-powered, 40-seat Dornier 328, which it plans to develop jointly with Deutsche Aircraft for targeted first flight in 2025 and certification under EASA Part CS-25 rules seven or eight years later.

H2Fly developed the HY4 to prove its ability to build a fully redundant powertrain with two hydrogen storage systems and redundancy for the fuel cells, cooling, and power distribution. The company believes that the test program has shown that it can close the technology gap to getting into service a production aircraft and scale the propulsion system for larger aircraft.