Taking into account the number of tons of fuel that a large aircraft consumes over the course of a year, and the thousands of aircraft that are continuously in the air, it is easy to understand the interest that BASF has in the announcement of the "film" that they have developed to reduce the friction of aircraft in flight.
This "film" has been called AeroSHARK because it mimics shark skin, and has very small riblets (of a few microns) along the flight line that reduce the plane's friction with the air.
The "film" is easily applied on the metallic surface of the plane, and is very resistant to external agents (sun, rain, cold, ultraviolet rays, pressure changes, etc...) so it stays on the plane for a long time.
There are already two airlines that have decided to put it on their planes. Lufthansa is going to place it on its fleet of 777F Cargo aircraft with the aim of saving 3,700 tons of kerosene per year and eliminating 11,000 tons of CO2 emissions.
A video can be seen at: https://youtu.be/-m0EiUyoQ48
It makes sense that they put this film on cargo planes because they have very few windows and therefore the savings achieved on them will be greater.
Swiss Air is also going to place it on its 777 planes, which are the largest it has, hoping to have similar results.
All airlines try to reduce the consumption of their planes as much as they can, because although their biggest "problem" is the pollution generated by their engines, any improvement in the consumption of their engines also translates into economic savings and less pollution.
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