Official site - http://hy4.org/
HY4 Passenger air travel with low noise, particulate matter or carbon dioxide – emission-free flight – is currently being transformed from a vision to a reality. The HY4 – the world’s first four-seater passenger aircraft powered solely by a hydrogen fuel cell system and electric propulsion – marks a milestone on this path. Electric flight with the HY4 is silent, environmentally friendly, has greater range and is safer than its predecessors. Longstanding experience in battery, fuel cell and hydrogen technology research in the aviation and energy sectors make the partners experts in the fields of ‘More Electric Aircraft’ (MEA) and ‘All Electric Aircraft’ (AEA). Fuel cells can be used in many areas of aviation. Common to all applications is the operation at high altitudes, at low air pressure and at low ambient temperatures. Requirements for safety and reliability are exceptionally stringent.