Before proceeding with the creation of a prototype of their own design, Piasecki’s team plans to “test” the fuel cell powertrain, the body of the Aerotec CoAX ultralight helicopter.

Piasecki Aircraft has announced that it will soon be using an air-cooled HyPoint turbocharged fuel cell and electric transmission to power an ultralight helicopter from EDM Aerotec. Thus, they hope to make the world’s first flight of a manned hydrogen-powered helicopter. In parallel, Piasecki Aircraft is developing its own green fuel model.

Piasecki Aircraft Corporation (PiAC) and EDM Aerotec have signed an agreement to jointly develop and license the CoAX-2D two-seat coaxial helicopter. The agreement provides PiAC with exclusive rights to manufacture, market and support CoAX-2D in North America and provides a joint basis for further research and development.

Piasecki Aircraft is also in the process of developing an entire five-seat multipurpose helicopter based on the HyPoint transmission. The draft name of the model is PA-890.

Each HyPoint SPM 20 fuel cell in the helicopter produces 20 kW of peak power. They are combined into a 560 kW main power unit, which is located in the middle of the fuselage above a pair of H2 gas cylinders at a pressure of 700 bar. Each of them holds up to 19.3 kg. hydrogen. A filtered air inlet will supply the fuel cells with oxygen, and air ducts with forced fan cooling will help regulate temperatures. According to Piasecki, the anodic tail gas oxidizer “returns energy back into the system for increased efficiency.”

It will be a slow-rotor helicopter with a winged design, with a large top rotor and wings that can fold in at the sides during VTOL and landing (and hovering) phases. They can also deploy to relieve pressure on the top propeller, allowing it to slow down for quieter, more efficient flight. An electric tail rotor provides torque and yaw control in hover or slow flight. According to the developers, the target flight range will be about 370 km plus reserve capabilities.

However, before proceeding to build a prototype of their own design, Piasecki’s team plans to “test” the fuel cell powertrain using a small, cheap, off-the-shelf compound helicopter. The company settled on Aerotec’s CoAX 2, a fairly affordable machine costing around $180,000. It’s an ultralight helicopter, so it will use a much smaller 80kW powertrain. Piasecki will remove the existing powertrain and install four SPM 20 fuel cells, one H2 tank, cooling systems and electric motors for the top two counter-rotating rotors.