He claims that since the 1990's major western governments have been secrectly adding radioactive isotopes and aluminum oxides to jet fuel to manipulate the weather.
Also, I focused on these two key points.
Firstly, "radioactive isotopes" in aviation Jet-A1 can be ruled out with the use of a Geiger counter. (And, the term is vague anyways).
Secondly, "aluminium oxides" are as a rule very abrasive. Such contaminants (for they would act as contamination) in aviation fuel would rather quickly destroy the engines, even IF they made it past the multiple fine-screened filters and pumps, etc.
Besides the abrasive nature of particles that might contaminate jet fuel, there is the ultimate fact of the combustion area, where the fuel is burned at temperatures that approach 4,000° C. These "particles" would then melt of course....and be deposited on the components of the engines....the High Pressure Turbine blades, and everything 'downstream' of the combustion chamber.
Should add that in most airliner applications, the jet fuel (besides of course supplying the engines) is
also used to help maintain oil temperatures. There is a component called the
"Fuel/Oil Heat Exchanger" (a bit like a car radiator). NOTE that this is a "win/win" also....the oil can be cooled, but the hot oil ALSO helps to keep the fuel from getting too cold, on flights that are long-duration, at very high altitude...keeps the fuel from "freezing".
Thing is, most people who fall for the myth of "chem"trails lack the scientific and technical knowledge background to properly vet such claims.