The engine determines the type of fuel to be used followed by an approval from the FAA to use that particular fuel for that particular engine. If the engine is not certified to use a particular type of fuel it doesn’t mean it can’t, but the FAA may give authority to operate with an “Experimental” registration.
The two main types of engines used in aircrafts today, they are propeller and jet engines. There are many variations of these two types of engines but aircraft engines are not the scope of the article.
Types of Aviation Gas Explained
Propeller (piston driven) engines use a variety of Aviation Gas (Avgas) products:
- Avgas 80
- Avgas 100
- 100 Low Led (LL) (Most Common in the United Stated)
100LL Avgas is the most popular in the United States and most aircraft engine manufactures get their engines certified for it. 100LL engines also have the advantage of being converted to use car gasoline with a few minor changes and a certification of approval. The appearance of 100LL is a light blue color with the smell of model super glue and is highly flammable. While Avgas 80 is used more in Europe, Avgas 100 has a green appearance.
Jet (turbine) engines can also use a variety of fuels:
- Jet A
- Jet A1
- Jet B
It’s interesting to note that Jet A and Jet A1 fuels are made from Kerosene. These fuels are not considered flammable until they reach a temperature of at least 30 degrees Celsius. However Jet B is a mix of both Kerosene and Gasoline and is considered highly flammable. Jet A is the most popular. Both of these fuels are colorless and can be defined as straw colored.
There are many tests in process to develop the first fuel cell electric aircraft engine, which will change the whole industry and make aviation even safer. If the engines could run on water instead of running on fuel, many more lives could be saved during an aircraft accident where the majority of injures result from fire. This is an exciting time in the history of energy, what will be next?