Aviation fuel: quality requirements

Aviation fuel is a product of oil production, responsible for the operation of engines of various types of air transport. Depending on the composition, scope and performance 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 particular type of fuel, providing the necessary speed and reliability. If you use a fuel that is not designed for this type of engine, you can reduce its working life and the power characteristics of the aircraft itself.

Jet Fuel for Aircraft

Aviation fuel - kerosene for jet engines - is used to refuel most aircraft. It can be of different brands. Six different types are used in our country, the features of the choice depend on the conditions and characteristics of the aircraft itself. For example, in the field of subsonic aviation kerosene TS-1, containing a large amount of sulfur in the composition, is used. And supersonic aircraft operate on the TS-8 or TS-6. Low-altitude aircraft are filled with TS-2 kerosene.

Kerosene - for aviation and not only

Kerosene is classified as light oil products. It is produced by direct distillation or recycling of oil. 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 propeller engines, as a lubricant for fuel installations. It has proved itself in many respects, in particular, to increase the wear resistance of the engine and low-temperature properties.
• Rocket science . To date, kerosene is widely used as a rocket fuel, although with low efficiency. In the future, ethane or propane is planned for this purpose.
• Manufacturing . Kerosene serves as 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 has high fire safety characteristics, is efficient and economical in use.
• Lighting . Although electricity is ubiquitous, kerosene lamps are also in no hurry to take their positions.

Popular types of aviation fuel in Russia and abroad

In the foreign market, several types of fuel for aviation are allocated. They are distinguished by the maximum boiling point, by the features of the fractional composition, by the flash point (for example, kerosene for naval aviation has the highest values), and so on.

The most popular product is aviation diesel fuel with an improved fractional composition, widely used in civil aviation. For example, the brand "Jet A-1." To him a number of strict requirements are made. But in developing countries, the fuel requirements are practically unregulated.

Aviation gasoline

The main sphere of application of aviation gasoline is piston engines of aircraft and helicopters of small volume. From automobile engines, they differ 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. Products obtained as a result of secondary processing, with the content of olefinic hydrocarbons, are not used in the production of aviation fuel.

Today, compared to the usual brands of gasoline for the automotive industry, aviation grades are produced relatively little - only 2%. By the way, some models of engines in aviation are able to operate on standard A-95 gasoline. However, aviation gasoline is characterized by greater stability and qualitative composition.

Quality indicators of aviation gasoline:

• Detonation resistance. It is determined on a fuel-air mixture of various composition.
• The crystallization temperature - the lower it is, the higher the quality.
• Special factional composition.
• Absence of tarry substances or their presence in the minimum amount.
• Absence of sulfur compounds and acids.
• High heat of combustion.
• High antiknock properties.
• Excellent storage stability.

All these characteristics determine the quality of aviation fuels, and hence the reliability of the engine.

Classification of brands and composition

Gasoline for aircraft engines is different in terms of grades. 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 a grade indicator, and the first is an octane number.

Unlike motor gasoline, aviation is not divided into winter and summer varieties. After all, in flight, there is almost always the same temperature, which depends little on the season change. But to any type of fuel in aviation, add more tetraethyl lead and strictly regulate the content of sulfur and tar. To ensure the necessary values of heat of combustion and crystallization temperature, toluene, isomerizate, pyrobenzene and other components are also added to the formulation.

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 to the characteristics of aviation fuel. In addition to strict compliance with the environmental standards for the classification of "Euro", there is a special technical regulation that regulates the requirements for aviation gasoline and diesel jet fuel.

For example, in gasoline used in aviation, there should be no surfactants and chemicals, or be present in a minimum amount that does not affect the performance properties. It must have a high stability to oxidation. It is admissible in its composition the content of tetraethyl lead. And in gasoline with a grade of at least 130 it is permissible to add a blue dye.

In jet fuel, there should be no foreign matter, such as water, sulfur, tarry substances. The crystallization temperature and kinematic viscosity are strictly regulated, and the parameters may differ for aircraft engines with subsonic and supersonic speeds.

As for the sphere of use, aviation gasoline is used only in aircraft engines. The use for any other purposes is strictly prohibited.