The additive content of jet fuels varies considerably, depending on whether the fuel is for civil or military use. Additive packages for avgas, on the other hand, are standard. Only additives that have been through a detailed and comprehensive evaluation and approval process are permitted.

Types of jet fuel additives

Tetra-ethyl lead

To improve the anti-knock characteristics of avgas, tetra-ethyl lead is added. There has been pressure to phase this additive out, due to concerns about lead emissions, however, there is currently no alternative that’s safe to use. Shell is working on finding a solution to remove lead from aviation fuels.

Antioxidants (gum inhibitors)

These kinds of additives must be used in avgas to prevent the formation of gum and other antioxidation products. Antioxidants (gum inhibitors) can also be used in jet fuels, however, they are considered more stable than avgas.

Metal deactivator

This kind of additive may be included to improve the thermal stability of fuels. It has been designed to mitigate the effects of dissolved trace metals, especially copper, which can impair the thermal stability of jet fuels.

Corrosion inhibitors

With rust being a potential concern for military and civil aircraft, corrosion inhibitors can be used to reduce weathering in the fuel system. They also improve the lubricating properties of jet fuels.

Fuel system icing inhibitors

These additives reduce the freezing point of any water that may be in the fuel system and prevent ice crystal formation that could restrict fuel flow.
They are mandatory in military jets but are not used in civil aircraft that have fuel heaters. They may be added to either jet fuel or avgas during the fuelling of small aircraft.

Static dissipater additives

These additives minimise the hazardous effects of static charges that build up during movement of jet fuels. They are sometimes used in avgas as well.


 

More in aviation fuels

Civil Jet Fuel

Today's kerosene jet fuels have been developed from the illuminating kerosene used in the early gas turbine engines. These engines needed a fuel with good combustion characteristics and a high energy content. 

Shell Water Detector

A fuel water detector can be used in jet fuel to find out if there is any water that cannot be seen with the naked eye.

Shell AeroJet

Our Shell AeroJet is a premium aviation fuel offering major benefits to pilots, operators and owners of turbine aircraft in Canada and Brazil. Shell AeroJet minimises or eliminates problems previously associated with the build-up of water in fuel tanks on business jets, turbo-prop aircraft and helicopters.

Aviation Safety Data Sheets

A safety data sheet (SDS) describes the hazards of substances and mixtures and makes recommendations for safe handling and use.