Re: aviation gas
The Army uses mostly JP4 for it's helicopters. It's a military designation for jet propellant. Jet A is a civilian designation for the most common form of jet or turbine engine fuel. It is mostly kerosene with a smaller percentage of gasoline (Naphtha). Military JP4 is mostly gasoline as described with a bit lower percentage of kerosene. Jet B isn't as common in the civilian world but has additives and blending to prevent freezing at high altitude.
Turbine fuels can start to gell or freeze at very low temperatures so they are blended for where they will have the best use. The military can afford the JP4 so that's what they use all the time. Jet A is the most common in the civilian world. Turbine fuel also has a tendency to form fungus so additives and different blending can reduce that risk. It shouldn't be stored for long periods due to this.
There are other forms for other purposes. The SR-71 had its very own type of fuel since it also used it as a coolant. It was JP7.
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