Japan Airlines is courting a trio of advanced propulsion developers as it explores the possibilities of hydrogen-powered regional aviation.
The Tokyo-based airline has “basic agreements” with H2FLY, Universal Hydrogen and ZeroAvia, and that it is working with the three competing hydrogen propulsion start-ups “to study the safety, economic feasibility and maintainability for bringing hydrogen-fuelled, next-generation aircraft” to Japan.
The deals were confirmed by the start-ups, all of which are developing hydrogen-electric propulsion systems for regional aircraft.
Such systems use hydrogen in fuel cells to make electricity and power electric motors. The technologies are still under development, though all three companies achieved milestone flights in 2023 and ZeroAvia is preparing to submit a certification proposal for its ZA600 powertrain to UK aviation regulators.
ZeroAvia is also advancing its second engine platform, the ZA2000, which is a hydrogen-electric propulsion system designed for 40-90 seat regional aircraft that it plans to enter into service in 2027.
That platform will be well-suited for 48-seat ATR 42s and 70-seat ATR 72s operated by Japan Air Commuter, which operates under the wing of JAL.
“As part of the agreement, Japan Airlines and ZeroAvia will collaborate on assessing operational parameters for retrofit hydrogen-electric aircraft for existing and prospective routes, as well as collaborating to define pathways for regulation, retrofit operations, hydrogen fuel infrastructure and engine maintenance, repair and overhaul,” ZeroAvia says.
German advanced powertrain developer H2FLY says it has ”signed an agreement to explore the feasibility of our hydrogen-electric power units as a power source for JAL flights”.
Across its companies, JAL operates some 50 regional aircraft. Japan Air Commuter operates nine ATR 42 and two ATR 72s, according to Cirium fleets data, while Hokkaido Air System flies four ATR 42s.
Cirium shows about 60 ATRs and De Havilland Canada Dash 8 regional turboprops in operation throughout the country.
“Japan plans massive investment in hydrogen supply and also in supporting the development of hydrogen aviation, so there is clear opportunity for exploring early adoption,” says James Peck, chief customer officer at ZeroAvia.
“Japan has long-shown that it is a market with an incredibly strong appetite for green aviation solutions and is home to JAL, one of the most established airlines in the world. As a partner, JAL is impressively demanding on the technical side; their operation is one of the most reliable in the world,” says Paul Eremenko, Universal Hydrogen’s chief executive.
Hydrogen is a high-potential technology with a specific energy-per-unit mass that is three times higher than traditional jet fuel. If generated from renewable energy through electrolysis, hydrogen emits no CO2 emissions, thereby enabling renewable energy to potentially power large aircraft over long distances but without the undesirable by-product of CO2 emissions.
Because hydrogen has a lower volumetric energy density, the visual appearance of future aircraft will likely change. This is to better accommodate hydrogen storage solutions that will be bulkier than existing jet fuel storage tanks.
Hydrogen has been safely used in the aerospace and automobile industries for decades. The aviation industry’s challenge now is to take this decarbonised energy carrier and adapt it to commercial aviation’s needs.
Aircraft manufacturers like Airbus and Boeing two primary uses for hydrogen:
Hydrogen propulsion: Hydrogen can be combusted through modified gas-turbine engines or converted into electrical power that complements the gas turbine via fuel cells. The combination of both creates a highly efficient hybrid-electric propulsion chain powered entirely by hydrogen.
Synthetic fuels: Hydrogen can be used to create e-fuels, which are generated exclusively through renewable energy.
The UK Civil Aviation Authority has launched a challenge for the aviation industry to help leverage the potential of hydrogen as a zero-carbon emission aviation fuel.
The regulator’s challenge will facilitate collaboration with industry and academia to improve understanding of hydrogen-related risks in aviation, identify gaps in policies, and propose new recommendations to develop net-zero policies.
Airbus has already modified a superjumbo A380 to test a hydrogen-powered jet engine as the European aerospace group prepares to bring a zero emissions aircraft into service by 2035. The partnership is an agreement with CFM International, a 50/50 joint company between GE and Safran Aircraft Engines, to develop an engine that can run on hydrogen. The converted test aircraft, the A380, will fly by the end of 2026.
The programme’s objective is to ground and flight test a direct combustion engine fuelled by hydrogen, which Airbus is betting on to enable the company to decarbonise in line with aviation’s climate change goals. The A380 flying test jet will be equipped with liquid hydrogen tanks prepared at Airbus facilities in France and Germany. Airbus will also define the hydrogen propulsion system requirements, oversee flight testing, and provide the A380 platform to test the hydrogen combustion engine in cruise phase.
CFM International will modify the combustor, fuel system, and control system of a GE Passport turbofan to run completely on hydrogen. The engine itself will be mounted along the rear fuselage of the A380 test jet to allow engine emissions, including contrails, to be monitored separately from those of the engines powering the aircraft.
“This is the most significant step undertaken at Airbus to usher in a new era of hydrogen-powered flight since the unveiling of our ZEROe concepts back in September 2020,” said Sabine Klauke, Airbus Chief Technical Officer. “By leveraging the expertise of American and European engine manufacturers to make progress on hydrogen combustion technology, this international partnership sends a clear message that our industry is committed to making zero-emission flight a reality.”
The venture comes amid increasing pressure on the aviation industry to cut pollution and meet zero-emission targets by 2050. Before the pandemic led to the grounding of much of the world’s aircraft, aviation accounted for roughly 2.4% of global emissions. “To achieve these goals by 2050 the industry has to take action now and we are,” said Gael Meheust, chief executive of CFM.
“Is hydrogen harder? Yes. Is it do-able? Absolutely,” said Mohamed Ali, vice-president and general manager of engineering at GE Aviation.
Executives said the decision to use an A380, the world’s largest passenger airline jet that has been phased-out at many airlines around the world due to its inefficiencies, would allow engineers more room for things like the tanks and the testing equipment. A commercial product available to airlines over the coming years will be much smaller. Airbus is expected to initially produce a regional or shorter-range aircraft.
In today’s aircraft, wings are where the fuel is stored, and they are in no way large enough to store the hydrogen that would be needed for a long flight. Hydrogen planes of the future could have extra-large fuselages, but more likely they will be what’s called blended wing, in which the planes are shaped like large triangles. This would allow them to store more fuel, but also reduce fuel consumption to make the aircraft aerodynamics even better.
Planes using hydrogen would emit only water, and initial tests suggest they can be just as fast as traditional planes, carrying more than a hundred passengers per flight over thousands of kilometres.
Most of the world’s hydrogen today is produced by reforming methane from natural gas – a fossil fuel - which produces carbon dioxide. Efforts are underway to develop green hydrogen by using an electric current from a renewable source to convert water into oxygen and hydrogen and reduce emissions in its production. If that is possible, along with no emissions from the planes themselves, aviation could become a green form of travel.
There are significant challenges that remain. If Europe were to fully achieve the environmental benefits of hydrogen-power – for example, for air travel, the production of clean – or green – hydrogen needs to be dramatically scaled up. Clean hydrogen is produced from water using an electric current from a renewable source, rather than from fossil fuels. Today only a tiny fraction of hydrogen used in Europe is categorically “clean.”
  • The author is an aviation analyst. Twitter handle: @AlexInAir
Related Story