Airbus Reveals Latest ZeroE Hydrogen Airliner Design
More energy efficiency means four, rather than six, open rotor engines
Airbus’ latest hydrogen airliner concept features four, rather than six, open rotor engines.

Airbus on Tuesday unveiled the latest iteration of its planned 100-seat hydrogen-powered airliner, reaffirming its commitment to the ZeroE program it now says could lead to the launch of commercial services towards the end of the 2030s. During its Airbus Summit presentations in Toulouse, the European aerospace group revealed a design with four wing-mounted open-rotor propulsion systems that Glenn Llewellyn, v-p of the ZeroE project, said was based on progress in achieving improved power density since it first showed a six-engine model in December 2020.

Six weeks after acknowledging that it will not meet its original goal of bringing a hydrogen airliner to market in 2035, Airbus said it is taking more time to maximize the potential of the technology. “We know we have made progress in our ability to make a fully hydrogen-electric aircraft, but the ecosystem isn’t ready and this gives us time to go further with the performance of an aircraft that can compete in the market,” said Bruno Fichefeux, Airbus’ head of future programs, adding that progress still needs to be made with the quantity, volume, and pricing of hydrogen fuel. “It’s not a step back, but rather an opportunity to go further.”

Llewellyn told journalists that his team is now pursuing the objective of being ready to test a complete hydrogen propulsion system, including engines as well as the storage and distribution technology, by 2027. “There is a lot of room for improvement as the fuel cells can get lighter and more aerodynamic, and also more compact and energy-dense,” he explained. “We are also refining the hydrogen storage technology, and this is why we are transitioning from a pressure-fed tank system to one with an integrated pump.”

Also part of the expanded ZeroE scope of work is a project with the Airbus UpNext technology incubator unit to develop a cryogenic propeller demonstrator. This will aim to capitalize on the need to cool hydrogen fuel to 252 deg C to cool the electronics and electrical components throughout the propulsion system; in the process, this reduces electrical resistance to support nearly unimpaired electrical transmission to make it more energy efficient.

In 2023, Airbus demonstrated a 1.2-MW hydrogen propulsion system, and last year it extended testing to cover the integrated fuel stack, electric motors, gearboxes, inverters, and heat exchangers. With partner Air Liquide Advanced Technologies, Airbus has developed the Liquid Hydrogen BreadBoard test facility at Grenoble in France. The planned integrated system testing in 2027 is to be conducted at the Electric Aircraft System Test House in Munich.

‘Radically Different’ Next-gen Airliner

At the same time, Airbus is expanding work on the next-generation single-aisle airliner that will succeed the A320 family. Fichefeux told the Summit audience that this will be able to run on 100% sustainable aviation fuel and deliver a 20% to 30% reduction in fuel burn, based not only on propulsion innovation but also on a new wing design and lighter materials throughout the airframe.

“The technology we are building today is developing at a faster pace than in the past, and what is in front of us will be a radically different aircraft,” said Karim Mokaddem, Airbus’ head of the aircraft of tomorrow.

In a veiled reference to rising transatlantic political tensions over tariffs and apparently weakening industrial alliances, he added, “This will all have to rely on a robust supply chain, and potentially a sovereign [European] supply chain given what we are going through today.”

Airbus next generation single-aisle airliner concept
During the Airbus Summit in Toulouse, the airframer revealed the latest concepts for airliners to replace the A320 family. (Airbus)

Nonetheless, GE Aerospace and its French partner Safran remain at the heart of Airbus’ single-aisle innovation roadmap through their CFM International joint venture, which is working towards demonstration flights with the Rise open fan engine later this decade. According to Mohamed Ali, GE Aerospace’s chief technology and operations officer, this powerplant will offer Airbus an engine with a bypass ratio equivalent to 60:1, compared to today’s 12:1 technology.

In a bid to deliver more lift and less drag, Airbus is developing concept wings that are longer and more slender. Sue Partridge, head of the group’s wing of tomorrow unit, explained that this means it has to develop the capability for outer wing sections to fold in while taxiing so that the new-generation narrowbodies can use existing airport gates.