Airbus is accelerating its efforts to bring zero-emission aircraft into service by 2035 with its ‘ZEROe demonstrator,’ an A380 flying testbed fitted with a hydrogen-powered test engine and liquid hydrogen storage and distribution system.
The ZEROe demonstrator will play an important role in bringing zero-emission aviation to reality and is slated to make its maiden flight in 2026. “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.”
In February, Airbus and CFM International (a 50/50 JV between GE and Safran Aircraft Engines) announced collaborating on a hydrogen demonstration programme to flight test a direct combustion engine fuelled by hydrogen. “This isn’t Airbus’ first experience with hydrogen-powered flight,” according to Mathias Andriamisaina, Airbus ZEROe Demonstrator Leader.
“From 2000 to 2002, Airbus was a key partner in the European Union’s Cryoplane research project. Building on these academic inquiries, we’re proud to take the testing of hydrogen combustion to the next level.”
ZEROe Demonstrator
Airbus will convert its A380 MSN1 test aircraft into the ZEROe demonstrator. MSN1 was the first-ever A380 to roll off the production line and made its first flight in 2005. This aircraft was used for development and certification testing of the A380, and it was later used to test the engine for the A350, which was mounted on top of the aircraft. As the largest and most spacious passenger jet ever built, the A380’s size makes it ideally suited to accommodate the hydrogen combustion engine, liquid hydrogen tanks and test paraphernalia and gives Airbus a huge amount of flexibility in what it can install in the aircraft in different locations, allowing it to evolve newer storage and distribution and propulsion systems over time.
“The aim of this flight laboratory will be to learn a huge amount about hydrogen propulsion systems in real ground and flight conditions. This is key in enabling us to achieve our ambition of having a zero-emission aircraft in commercial service by 2035,” said Airbus Vice-President, Zero-Emission Aircraft, Glenn Llewellyn.
In addition to providing the A380 platform to test the hydrogen combustion engine in the cruise phase, Airbus will also define hydrogen propulsion system requirements and oversee flight testing. The airframer will also modify the aircraft cockpit to manage and monitor the hydrogen propulsion system in flight. An additional throttle control will be installed to allow the pilots to control the hydrogen engine, and an additional cockpit display will also be fitted to monitor the parameters of the hydrogen systems onboard the aircraft.
“The A380 MSN1 is an excellent flight laboratory platform for new hydrogen technologies,” says Mathias Andriamisaina, Airbus ZEROe Demonstrator Leader. “It’s a safe and reliable platform that is highly versatile to test a wide range of zero-emission technologies. In addition, the platform can comfortably accommodate the large flight test instrumentation that will be needed to analyse the performance of the hydrogen in the hydrogen-propulsion system.”
The A380 flying testbed will be prepared at Airbus facilities in France and Germany to accommodate liquid hydrogen tanks. The ZEROe demonstrator will carry four liquid hydrogen tanks in a caudal position (anatomical term denoting the coccyx, or lowest part of the spinal column). A conditioning system will receive the liquid hydrogen and transform it into its gaseous form before introducing it into the engine, where it will be combusted for propulsion. The demonstrator aircraft will be modified into a hydrogen propulsion flight laboratory and will feature a stub incorporated between the two doors at the upper level. The hydrogen-powered engine will be mounted at the end of this stub. Data on the performance of the hydrogen storage and distribution system and the hydrogen-powered engine will be relayed back to the flight test station, which will allow the test engineers to operate the tests in real-time during the flight. Data will also be transferred to ground stations via telemetry. The liquid hydrogen tanks will be placed inside a hermetically sealed container. Each technology component – the hydrogen tanks, hydrogen combustion engine and liquid hydrogen distribution system – will be tested individually on the ground. Upon completing these tests, the complete hydrogen propulsion, storage and distribution system will be extensively ground tested and then move onto flight testing.
Airbus has tested pioneering technologies across several demonstrator programmes, ranging from path-breaking E-Fan family, which highlighted the potential for all-electric flight; Vahana and CityAirbus demonstrators showcasing the potential for sustainable urban air mobility and the E-Fan X hybrid-electric propulsion demonstrator. A demonstrator aircraft is primarily used to test and prove the viability of designs, processes, fuels, materials and equipment, both on the ground and in the air. The information gathered during this process is further used to refine and certify the finished product. Such aircraft also showcase advanced future technologies to a wider audience, from government officials and investors to journalists and the general public.
Pure Power
CFM International (CFM) will modify a GE Passport turbofan with changes to its combustor, fuel system, and control system to run on hydrogen. The engine will be mounted on the rear fuselage of the flying testbed and was chosen due to its physical size, advanced turbomachinery, and fuel flow capability. The engine’s placement at the rear of the aircraft ensures that there is sufficient distance from the A380’s four engines, which are mounted on the wing. This will allow engine emissions (including contrails) to be monitored separately.
“Hydrogen combustion capability is one of the foundational technologies we are developing and maturing as part of the CFM RISE Programme,” said Gaël Méheust, President & CEO of CFM. GE’s Passport turbofan is assembled in the US, and CFM will execute an extensive ground test programme before the A380’s flight test. Both GE Aviation and Safran have significant hydrogen experience. Safran has done extensive work on rocket motors, and GE has more than eight million hours of operating experience using blended hydrogen fuels in power turbines.