Alaska Airlines has officially handed over a Dash 8-400 to ZeroAvia, which will equip it with a hydrogen-electric propulsion system in an effort to extend the range and applicability of emission-free flight technology. The twin engine will thus probably be equipped with the future ZA2000 system, which should make it possible to equip regional aircraft… At a minimum. (This article was published in Airlines and Destinations n°2829)
A Dash 8 Q400 intended to be re-engined
On May 1, Alaska Airlines presented ZeroAvia with a Dash 8 Q400 regional aircraft that will be equipped with a hydrogen-electric propulsion system in an effort to extend the range and applicability of flight technology. without emissions. The 76-seat Q400 will be developed by ZeroAvia. When Horizon Air, Alaska Airlines’ regional carrier, retired its Q400 fleet, it set aside one of the aircraft for research and development to advance zero-emissions technology in aviation . The aircraft has been repainted with a special livery to underline the innovative mission of this partnership.
1.8 MW on HyperTruck test bench
ZeroAvia also showcased its multi-megawatt modular electric motorization system in a 1.8 MW prototype configuration at the event, demonstrated by ZeroAvia’s 15-tonne HyperTruck testbed. Combined with higher temperature PEM fuel cells and advanced power electronics – two technologies that ZeroAvia is currently developing in-house – advanced electric motor technology is one of three key elements to achieve hydrogen fuel cell commercially relevant to regional aircraft and beyond. Aligning ZeroAvia’s powertrain with the Dash 8-400 airframe will create a commercially viable zero-emissions aircraft featuring fuel cell engine technology five times more powerful than has been demonstrated so far now. “The launch of this program puts us on track for a test flight next year and accelerates our progress toward the future of zero-emissions flight for Alaska Airlines and the world,” said Val Miftakhov, Founder. and CEO of ZeroAvia.
ZA2000 after ZA600 on Dornier Do-228
ZeroAvia’s recent advancements pave the way for potential flight of the Q400, also known as the Dash 8-400, but also demonstrate rapid progress towards certification of the ZA2000 propulsion system. ZeroAvia has already proven itself in flight testing. In January 2023, ZeroAvia flew a 19-seat aircraft equipped with its prototype 600 kW hydrogen electric motor (ZA600). The 19-seat twin-engine aircraft has been refitted into an engineering testbed configuration to incorporate ZeroAvia’s hydrogen-electric engine that powers the propeller on the left wing, running alongside a single Honeywell TPE- 331 on the right wing for proper redundancy to safely test the new propulsion technology. For this test program ZeroAvia worked with the CAA (the UK DGAC) to meet a much larger set of stricter than those ZeroAvia had used for its 6-seater prototype in 2020. This flight follows the demonstration of a 250 kW system in 2020 – the Piper M350 – which was then the largest aircraft in the world to use a new emission-free power source. The certifiable ZA2000 system will include ZeroAvia’s high temperature PEM fuel cells (HTPEMs, short for High Temperature Proton Exchange Membrane) and liquid hydrogen storage, essential to provide the density of energy required for the commercial operation of large regional turboprop aircraft.
A record specific power of 2.5 kW/kg per cell
The first tests of the 20 kW pressurized HTPEM modules took place at ZeroAvia’s research and development center in the United Kingdom and demonstrated a record specific power of 2.5 kW/kg at the cell level, paving the way for potential densities of more than 3 kW/kg. “It is necessary to increase the temperature and the pressure inside the fuel cells in order to obtain a commercially viable product. The increase in temperature and pressure enables air cooling, reduces cooling drag, simplifies the system and ultimately enables much more demanding applications,” comments ZeroAvia. Further research is expected to achieve specific fuel cell system power of more than 3 kW/kg, which represents a step change in performance compared to traditional fuel cell technologies, thus making propulsion by fuel cell commercially viable for large aircraft, with a transport capacity ranging from 40 to 80 seats to start, since the engine manufacturer also wants to offer its system to rotary wings. This new generation of fuel cells could also be sufficient to enable the implementation of electric propulsion systems for single-aisle turbine aircraft with more than 100 seats such as the Boeing 737 and the Airbus A320.
From PEM to HTPEM, a gain in drag
The components used in the ZeroAvia system have already been validated by independent third-party testing at several independent laboratories, including a leading US Department of Energy National Laboratory. These trials confirm the ability of HTPEM systems to accelerate the development of large hydrogen-electric powertrains for large aircraft. ZeroAvia’s recent first flight of a 19-seat aircraft used low-temperature PEM fuel cell (LTPEM) systems. Current LTPEM systems perform well in the sub-megawatt scale of these small aircraft, but the lower stack core temperatures make it more difficult to remove heat from larger systems. HTPEM technology eliminates a number of fuel cell system components and reduces cooling drag, enabling commercially relevant payload and range. ZeroAvia’s HTPEM can also provide greater durability, reducing operating costs for airlines. ZeroAvia previously signed an engineering partnership with De Havilland of Canada, the manufacturer of the Dash 8 family of aircraft – which bought the intellectual rights from Bombardier – to allow the exchange of data.
