Hydrogen propulsion aviation is evolving faster than expected. H2eVTOLs, as they’re known, have significant potential in an increasingly climate-conscious and cost-conscious society. Most of the news has been about pure electric Vertical Takeoff and Landing (eVTOL) aircraft that operate by battery power and electric motors. H2eVTOLs, by contrast, have hydrogen fuel cells that power electric motors, and in the odd case, run on liquid hydrogen.
“Hydrogen packs three times the energy per kilogram as jet fuel, emits no carbon emissions, and can be sourced from water,” says Danielle McLean, founder of HYSKY Society, a nonprofit dedicated to advancing hydrogen aviation. McLean notes that hydrogen has been used to power rockets for decades.
But for business aviation and Urban Air Mobility, hydrogen is in its infancy. Less than a dozen aircraft start-ups are using either fuel cells or liquid hydrogen as the main power for fixed-wing aircraft or rotorcraft, and most are still trying to work out the concepts, or at best, flying a scaled-down prototype.
There is virtually no hydrogen infrastructure in airports, and concerns remain about safety with hydrogen’s reputation for flammability. Industry watchdogs such as Germany’s Federal Institute for Materials Research and Testing recently reported that hydrogen aircraft are “no more dangerous than conventional ones—safer in some respects.” Whether that reputation catches on remains to be seen.
Some experts also argue that the extraction, transportation, and storage infrastructure for hydrogen are simply too expensive to justify at the moment. But proponents, including the world’s largest aircraft manufacturer Airbus, are fiercely loyal to the advantages they see with hydrogen in the long term. Airbus expects to have hydrogen-powered commercial regional jets flying in the next 10 years. However hydrogen flight develops, it’s clear it has the potential to be instrumental role in decarbonizing aviation.
Here are six leading H2eVTOLs that plan to commercialize their aircraft by the end of the decade.
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AMSL Aero Vertiia
Image Credit: AMSL Aero AMSL Aero claims its Vertiia will be the world’s first-to-market, long-range H2eVTOL, possibly entering service by 2027. “Powered by green hydrogen, the Vertiia is quieter and up to 70 percent less expensive than a helicopter or small-fixed wing aircraft,” the company told Robb Report. The five-person H2eVtol, designed for Australia’s extreme conditions, has a V-tail to facilitate higher speeds and safety. It claims it can take off and land in a tennis court. Its maximum airspeed will be about 190 mph, with a range of about 621 miles and payload of 1,100 pounds.
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Sirius Business Jet
Image Credit: Sirius Business Jet Switzerland’s Sirius Business Jet is ideally positioned for regional transport, given its impressive range of 1,150 miles, which is nearly double that of even the Vertiia. Like many eVTOL designs, the Sirius Business Jet will have both vertical takeoff potential as well as shifting rotors that allow forward flight. It is designed to cruise at 323 mph as high as 30,000 feet, carrying three passengers and a pilot. The company says noise pollution will be less than 60 decibels (comparable to a dishwasher). The SiriusJet will also come with a built-in parachute system for the whole airframe. The company recently released a version of its new electric motor and claims it will begin flight tests of a full-scale prototype next year. Unlike the others on this list, it will operate on liquid hydrogen which will be stored in cryogenic tanks. BMW Designworks did both the interior and exterior.
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NEX Aero
Image Credit: Nex Aero Like the other aircraft on this list, the NEX Aero is still a work in progress. The German team behind the aircraft says it will have a range of over 300 miles and zero emissions (only water vapor as a byproduct), as well as lower maintenance and operational costs compared to conventional aircraft with a similar payload capacity of 441 pounds. Its scaled prototype first flew in 2022. Now, the company is flight testing its first-generation fuel-cell system. Nex hasn’t released a timeline for when it plans to flight-test a full-scale model, but estimates that its entry into service will be before 2031. The lineup for launch cities is purely wishful thinking at this point, but NEX is targeting its home city of Berlin, New York City, Singapore, Dubai, and NEOM in Saudi Arabia.
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LuftCar
Image Credit: LuftCar The LuftCar’s designator as a “multi-purpose modular Autonomous Air and Road Mobility (AARM) eVTOL” is a mouthful, but the vehicle is designed for use in the air and on the road. In flight, the concept will be powered by a hydrogen fuel cell and wing assembly that attaches and detaches to its airframe. The vehicle is designed to fly under a 4,000-foot ceiling at speeds of up to 220 mph, with a maximum range of 300 miles. Once detached, the car will be able to travel 150 miles. The Orlando-based company previously said it plans to release a full-scale production model this year, but it’s not clear if that timeline still stands.
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Urban Aeronautics CityHawk
Image Credit: Urban Aeronautics Fancraft technology is the most striking feature of the CityHawk—a four-passenger autonomous eVTOL with a footprint four times more compact than many of its peers. Designed to fit into a parking space, the CityHawk’s small footprint is achieved fully enclosed rotors and guiding vanes as opposed to a multi-copter configuration. This aircraft is designed for weaving around city skyscrapers, with the ability to land on rooftops. Israel-based Urban Aeronautics has announced prototype flights next year, with first deliveries by 2029.
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Alaka’i Technologies SkaiCab
Image Credit: Alaka’i Technologies The SkaiCab is H2eVTOL with a fuel cell that powers six electric motors. Its rotors spin at lower RPM levels than most rotorcraft to limit noise. “Extending private aviation across larger urban areas is a perfect application for eVTOLs,” says Bill Spellane, COO of Alaka’i Technologies. The five-passenger aircraft will have a payload capacity of 1,000 pounds, 115 mph top speed, and range of 150 miles. The New England company also claims a flight duration of up to four hours, with liquid-hydrogen refueling taking less than 10 minutes. The interior by BMW Designworks has both ergonomics and contemporary design in mind. Alaka’i hasn’t released a timeline toward certification.
