The first and most important thing is to be clear that large aircraft over 100 tons of weight need a huge engine thrust to get in the air, and that cannot be achieved with the added weight of batteries. The electric alternative today is not an option for these aircraft.
With current technology and with a forecast of about 30 years, the possibility for large aircraft to fly without polluting is to have non-polluting fuels and powerful engines that are capable of running on these fuels. Period.
And for many years, all the major players in the aeronautical world (aircraft manufacturers and engine manufacturers) have been looking for ecological alternatives so that these large aircraft can fly without generating environmental pollution.
It is a huge problem but it has a solution, although it is not yet cheap, but when we want things we get them.
Years ago, flights were carried out with engines that burned a mixture of normal fuel and ecological fuel, and it was found that this was viable, although still expensive, due to the high cost of ecological fuel and its scarcity.
Work has continued on this path and recently Rolls-Royce (one of the largest aircraft engine manufacturers in the world) has announced a new engine model called UltraFan that can run on current conventional fuel, or also only on ecological fuel ( SAF), and that engine has enough power to put aircraft into flight.
This new engine is much more efficient than the previous ones, but in my opinion one of the most important features is that it can run on SAF fuels. And the problem that arises now is the capacity of the industry to produce this type of fuel at "reasonable" prices.
It is up to the Governments to promote ecological alternatives to travel in the market, encouraging the production of ecological fuels and their consumption. At the same time, informing citizens so that they are aware of the "problem" and assume a certain extra cost to fly without polluting.
Awareness is essential if we want the situation to change for the better. But many times I wonder how many really want it and how much they are willing to pay.
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