Historic first hydrogen-powered helicopter flight: These are the details

For three minutes and 16 seconds, the modified R44 helicopter was up in the air in the first-ever piloted hydrogen-powered helicopter flight. Unither Therapeutics, a parent company of Unither Bioélectronique, announced the milestone that constitutes the first successful flight using this technology.

The test used a modified R44 model, manufactured by Robinson Helicopter Company. The original piston engine (Lycoming IO-540) was removed to integrate two low-temperature proton exchange membrane (PEM) fuel cells, a lithium-ion booster battery pack, and MagniX electric motor. The hydrogen tank was installed beneath the tail boom.

One of the main challenges and technical developments in the aircraft was the cooling system. In an interview with Vertical Magazine, Mikael Cardinal, VP of Program Management and business development for Organ Delivery Systems at Unither Bioelectronics, explained that extracting the heat, around 50% of the energy generated by the fuel cells, was one of the main challenges, especially during hovering flights, that do not allow for the ram flow available at flights in higher airspeeds. 

Robinson stated that 90% of the energy requirements during the test flight were covered by the PEM fuel cells, and the battery was pivotal in covering the demand spikes, and retained 80% of the charge at the end of the flight.  

This aircraft is part of the partnership ‘Project Proticity’ between the aircraft manufacturer and Unither Therapeutics, an agreement between the companies to develop the helicopter. The companies will also develop a R66 hydrogen-powered model.

Similarly, Robinson is working on integrating a liquid hydrogen storage system, which according to the company, could enable extended-range missions, as the test was done using gaseous hydrogen.