Cars use gasoline but jets use something closer to diesel, maybe kerosene, that’s less combustible. Wouldn’t they need a _more_ volatile or explosive fuel to get the most thrust for performance?
In: Engineering
Octane ratings are not a measure of how much energy is stored in the fuel. They are a measure of how stable the fuel is: which is to say, how difficult it is to get it to combust. The higher the octane, the more energy input required to start the combustion. Different engine designs require a different octane rating for the fuel they run on.
In terms of actual energy per gallon, all these fuels you mention are relatively similar. Jet fuel is higher than gasoline but lower than diesel. But even that isn’t really related to the power output/performance of an engine. An engine design that can put to use 1 gallon per minute of jet fuel will obviously be way more powerful than a diesel engine that can only burn 1/10 of a gallon per minute, assuming absolute efficiency. Different fuels are chosen (or really, designed) for their behavior in certain conditions rather than just their energy density.
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