There are several companies trying to get medium-sized planes to fly with hydrogen, in order to avoid the pollution that flights produce today. And the most positive thing is that real tests of some aircraft have already been carried out.
I know of two cases, but I'm sure there will be more.
In one case the company is called Universal Hydrogen (in the USA) which has carried out a test flight using an ATR 72 (40-passenger plane) modifying the engines.
ATRs are well-known aircraft in the market for their reliability and versatility. More than 1,000 aircraft have been manufactured and used by many airlines for regional flights.
The idea of Universal Hydrogen is to modify the engines by placing hydrogen cells that directly feed the electric motor that drives the propellers. And by not using batteries, weight and physical space are eliminated, something very important in the aeronautical world.
A video can be seen on Twitter: https://twitter.com/i/status/1632822330157150213
The company has a goal of putting planes on the market in 2025, but it is not clear that in that short space of time it will receive FAA approval to fly. And if it does not happen in the year 2025, it will be shortly after, but it seems that it is a feasible reality.
Another case is that of Zero Avia Zero Avia https://www.zeroavia.com/ which is working at the Birmingham airport to place there a hydrogen infrastructure for regional aircraft.
Not long ago they carried out some tests with a Dornier 228 airplane whose engines were modified to make them fly with hydrogen cells. A video can be seen at: https://www.youtube.com/watch?v=cp8MoFaaKy8
Lo que parece claro es que los aviones regionales de hasta unos 100 pasajeros podrían volar en menos de 10 años sin contaminar el medio ambiente. Y esto es una buena noticia para la aviación.
I hope it becomes a reality as soon as possible!
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