Aviation fuel is an oil product that is responsible for the operation of engines of various types of air transport. Depending on the composition, scope of application and operational characteristics, the fuel is of different types. There are two main ones: aviation kerosene (also called jet fuel) and aviation gasoline.
Each engine is developed taking into account the use of a specific type of fuel, providing the necessary speed and reliability. If you use fuel that is not intended for this type of engine, you can reduce its working life and power characteristics of the aircraft itself.
Jet fuel for aircraft
Jet fuel - kerosene for jet engines - is used to refuel most aircraft. It comes in various brands. In our country, six different types are used, the features of the choice depend on the conditions and characteristics of the aircraft itself. For example, in the field of subsonic aviation, TS-1 brand kerosene is used, which contains a large amount of sulfur in the composition. And supersonic aircraft operate on the TS-8 or TS-6 brands. Low-altitude aircraft are refueled with TS-2 kerosene.
Kerosene - for aviation and not only
Kerosene is attributed to light types of petroleum products. It is produced by direct distillation or secondary oil refining. The boiling point of this product, depending on the composition, can vary from 150 to 250 degrees.
Here are the main areas of application of kerosene:
- Aviation Here, kerosene acts as an aviation fuel for refrigerant and screw engines, as a lubricant for fuel installations. He has proven himself in many ways, in particular, increasing engine wear resistance and low temperature properties.
- Rocket science . To date, kerosene is widely used as rocket fuel, although with low efficiency. In the future, for this purpose they plan to use ethane or propane.
- Production . Kerosene is an excellent raw material for the production of polyethylene and polypropylene, as well as other synthetic materials.
- Heating . In countries where there is no central heating system, kerosene is widely used. It is characterized by high fire safety characteristics, efficient and economical to use.
- Lighting Although electricity is used everywhere, kerosene lamps are also in no hurry to give up their positions.
Popular types of aviation fuel at home and abroad
In the foreign market, several types of fuel for aviation are distinguished. They are distinguished by the limiting boiling point, by the characteristics of the fractional composition, by the flash point (for example, kerosene for marine aviation has the highest rates), and so on.
The most popular product is aviation diesel fuel with improved fractional composition, which is widely used in civil aviation. For example, the brand "Jet A-1." A number of strict requirements are imposed on him. But in developing countries, fuel requirements are practically unregulated.
Aviation gasoline
The main scope of aviation gasoline is piston engines for small-volume aircraft and helicopters. They differ from automobile engines in the system of forced fuel injection, which means that the requirements for aviation fuel should be somewhat different.
The composition of aviation gasolines includes carefully tested components obtained as a result of special technological processes. For example, aromatization of oil or catalytic reforming. Recycled products containing olefin hydrocarbons are not used in the production of aviation fuel.
Today, compared with the usual brands of gasoline for the automotive industry, relatively few aviation varieties are produced - only 2%. By the way, some models of engines in aviation are able to work on standard A-95 gasoline. But still, aviation gasoline is more stable and of high-quality composition.
Quality indicators of aviation gasoline:
- Knock resistance. It is determined on a fuel-air mixture of various compositions.
- Crystallization temperature - the lower it is, the higher the quality.
- Special fractional composition.
- Lack of resinous substances or their presence in the minimum quantity.
- Lack of sulfur compounds and acids.
- High calorific value.
- High antiknock properties.
- Excellent storage stability.
All these characteristics determine the quality of aviation fuels, and therefore the degree of reliability of the engine.
Grade classification and composition
Gasoline for aircraft engines varies in terms of grade. It is this criterion that is responsible for the power developed by the engine. For example, for B-91/115 gasoline, the second number is just an indicator of grade, and the first is an octane number.
Unlike gasoline, aviation is not divided into winter and summer grades. Indeed, in flight there is always almost the same temperature, which depends little on the change of season. But to any type of fuel in aviation, more tetraethyl lead is added and the standards for sulfur and tar content are strictly regulated. To ensure the necessary indicators of calorific value and crystallization temperature, toluene, isomerizate, pyrobenzene and other components are also added to the composition.
The presence of special additives in the composition is also evidenced by the color of aviation fuel. It is usually bright yellow, bright green or orange.
Quality standards
In our country, there are special requirements for the characteristics of aviation fuel. In addition to strict observance of environmental standards according to the Euro classification, there is a special technical regulation regulating the requirements specifically for aviation gasolines and diesel jet fuel.
For example, gasoline used in aviation should not contain surfactants and chemicals, or be present in a minimum amount that does not affect operational properties. It must have high oxidation stability. The content of tetraethyl lead is permissible in its composition. And in gasoline with grades of at least 130, it is permissible to add blue dye.
Foreign fuels should be free of impurities such as water, sulfur, tarry substances. The crystallization temperature and kinematic viscosity are strictly regulated, and indicators may vary for aircraft engines with subsonic and supersonic speeds.
As for the scope of use, aviation gasoline is used only in aircraft engines. Use for any other purpose is strictly prohibited.