Airbus is continuing to pursue its goal of one day flying a zero-emission and commercially-viable passenger aircraft powered by hydrogen. The company announced Tuesday plans to test a new hydrogen-powered engine that will be installed on a modified Airbus A380 aircraft.
The European aircraft manufacturer said it plans to conduct test flights by the middle of the decade. The new engine was developed in cooperation with General Electric's aviation arm CFM International and France's Safran.
The companies modified an existing engine already in use to handle much higher temperatures required to burn hydrogen. Airbus expects test flights to be around 2026. Airbus chose the A380, its largest plane, because of its capacity to carry large amounts of fuel and equipment.
There are currently two known ways to use hydrogen to fly airplanes. The first method is straightforward - burn the hydrogen just like normal fuel. The second method is using hydrogen in a fuel cell to generate electricity, which would in turn then power electric engines.
Both technologies work, but there are significant engineering and economic hurdles to overcome before they are viable for use in commercial flights. One of the major issues is that hydrogen isn't as energy-dense as jet fuel, which means that there has to be more of it stored on an aircraft.
As a result, huge aircraft designed to go long distances would require significantly larger fuel tanks. And those tanks would need to be cooled down to minus 420 degrees Fahrenheit to liquefy the hydrogen.
The added equipment needed to cool and store the hydrogen would add significant weight to the aircraft, reducing the number of people and cargo it can carry. This poses a major problem for airlines, as with the current technologies, such aircraft would not be economically viable.
In modern planes, fuel is stored in the aircraft's wings. The hydrogen needed to fly a typical passenger plane long distances would not fit on modern wings. This means that future hydrogen planes might need extra-large fuselages. Companies are experimenting with new plane designs, including a proposed "blended wing" aircraft, which look like large triangles, which will be able to store more fuel.
Airbus' rival Boeing is taking a very different path in slashing its carbon emissions. Boeing is focusing more on developing sustainable aviation fuels, which currently only make up about 1% of the jet fuel supply. Boeing CEO Dave Calhoun previously expressed his skepticism about hydrogen planes, predicting that they wouldn't be practical to use until after 2050 or until the technology needed would be available.
