Nearly all gas-turbine airplanes run on jet fuel. Also known as aviation turbine fuel, it’s a type of kerosene that’s made of ultra-refined petroleum. It was invented in the mid-1900s. Since then, jet fuel has been used to power countless commercial and private airplanes.
Rather than running entirely on jet fuel, though, many airplanes use additives. There are additives available for jet fuel. They consist of liquid chemicals that improve the performance or properties of jet fuel. To learn more about jet fuel additives, keep reading.
#1) FSII
One of the most common types of jet fuel additives is fuel system icing inhibitor (FSII). As the name suggests, it’s designed to inhibit the formation of ice. Airplanes, of course, fly at high altitudes where the air is cooler than that of the ground level. The air at 30,000 feet above sea level, for instance, may range from minus 40 degrees to minus 50 degrees Fahrenheit.
FSII is a jet fuel additive that raises the freezing point of jet fuel. It’s mixed directly with jet fuel. Once added, the jet fuel can be exposed to lower temperatures without freezing.
#2) CL/LI
Some airplanes use a corrosion inhibitor/lubricity improver (CI/LI). It’s another common type of jet fuel additive. Rather than raising the freezing point of jet fuel, though, CI/LI is designed to inhibit corrosion and improve lubrication.
Jet fuel travels through multiple parts, some of which are made of metal. Metal parts, of course, can develop corrosion. Corrosion is the result of oxidation: exposure to oxygen triggers a chemical reaction with iron, thus causing the metal to corrode. CL/LI is a type of jet fuel additive that protects against corrosion.
In addition to protecting against corrosion, CL/LI improves lubrication. It lubricates the inner parts through which the jet fuel travels.
#3) Gum Inhibitor
The third type of jet fuel additive is a gum inhibitor. Gum inhibitors are essentially antioxidants. They are designed to protect against the formation of gum while subsequently improving the performance of jet fuel.
Gum can form due to oxidation. When jet fuel oxidizes, deposits may accumulate into a solid mass. Known as gum, this solid mass can block fuel lines and create other problems. Gum inhibitors are additives that are designed to prevent this from happening. When added to jet fuel, they’ll protect the jet fuel from oxidation and, thus, the formation of gum.