The test flight of an adapted ATR-72 regional airliner was hailed as a breakthrough moment for hydrogen as a fuel for aircraft in the near future. We might soon be travelling on aircraft that cruise through the skies on hydrogen instead of fossil fuels. That’s the hope of Los Angeles-based startup Universal Hydrogen which has turned a turboprop-powered regional airliner into a hydrogen plane.
Earlier this month, its plane, nicknamed “Lightning McClean,” successfully completed a 15-minute test flight in the US with a pilot and two flight crew on board. It made two passes around the airfield at Moses Lake, Washington, at a low altitude of about 3,500 feet, according to the developer of the airplane, Universal Hydrogen. During the second circuit over the airport, the test pilots throttled back the conventional engine and cruised primarily on the one hydrogen-powered engine.
All the noise was coming from the left side. It was silent,” the pilot, Alex Kroll, told the Seattle Times. The adapted ATR 72 aircraft can usually accommodate 50 passengers but the large liquid-hydrogen tank reduces the sitting capacity down to about 40. The company claims that the plane is by far the largest aircraft to cruise principally using hydrogen power.
In 1988, the Soviets flew a hybrid airplane with liquid hydrogen as an experiment. However, only one of the three engines was powered by hydrogen and the Soviet Union’s ambitious Hydrogen Energy Program was shelved with the demise of the USSR. Lightning McClean flew with a hydrogen engine under the right wing and a conventional aviation fuel engine under its left wing for safety.
Green hydrogen is generated when electricity runs through water. This means water vapor is the only emission trailing a hydrogen airplane if the electricity is from renewable sources. “Hydrogen is the only answer for aviation to get anywhere near the Paris Agreement targets,” Paul Eremenko, the CEO of Universal Hydrogen, said in a statement.
According to the company, they have already made deals with carriers in the US and Europe for its hydrogen airliners. Connect Airlines, which will begin regional turboprop service this spring, has placed a first-position US order with Universal Hydrogen to convert 75 ATR 72-600 regional airplanes to hydrogen powertrains.
Universal Hydrogen expects that the deliveries will start in 2025. However, the current technology is designed only for short hauls. With the large liquid-hydrogen tanks onboard the range of an aircraft has to be compromised. The company estimates their current models designed for regional airliners can fly only about half of the gas-fueled plane’s 1,600-kilometre range. The company says it’s working on developing a jet engine that can burn hydrogen for longer-haul aircraft.
