Aviation fuel is a specialized type of petroleum-based fuel used to power aircraft. It is generally of a higher quality than fuels used in less critical applications such as heating or road transport, and often contains additives to reduce the risk of icing or explosion due to high temperatures, amongst other properties.

Most aviation fuels available for aircraft are kinds of petroleum spirit used in engines with spark plugs i.e. piston engines and Wankel rotaries or fuel for jet turbine engines which is also used in diesel aircraft engines. Alcohol, alcohol mixtures and other alternative fuels may be used experimentally but are not generally available.

Avgas is sold in much lower volumes, but to many more individual aircraft, whereas Jet fuel is sold in high volumes to large aircraft operated typically by airlines, military and large corporate aircraft.

The Convention on International Civil Aviation, which came into effect in 1947, exempted air fuels from tax. Australia and the USA oppose a worldwide levy on aviation fuel, but a number of other countries have expressed interest.Fact: date=May 2008

Avgas

main: Avgas Avgas is a high-octane fuel used for aircraft and racing cars. The term Avgas is a portmanteau for aviation gasoline, as distinguished from mogas (motor gasoline), which is the everyday petroleum spirit used in cars. Avgas is typically used in aircraft that use reciprocating or wankel engines.

Jet fuel

main: Jet fuel Jet fuel is a clear to straw colored fuel, based on either an unleaded paraffin oil (Jet A-1), or a naphtha-kerosene blend (Jet B). It is similar to diesel fuel, and can be used in either compression ignition engines or turbine engines.

In use

Aviation fuel is often dispensed from a tanker or bowser which is driven up to parked aeroplanes and helicopters. Some airports have pumps similar to filling stations that aircraft must taxi up to. Some airports also have permanent piping to parking areas for large aircraft.

Regardless of the method, aviation fuel is transferred to an aircraft via one of two methods: overwing and underwing. Overwing fuelling is used on smaller planes, helicopters, and all piston-engine aircraft. Overwing fuelling is similar to car fuelling — one or more fuel ports are opened and fuel is pumped in with a conventional pump. Underwing fuelling, also called single-point, is used on larger aircraft and for jet fuel exclusively. For single-point fuelling, a high-pressure hose is attached and fuel is pumped in at up to 50 PSI. Since there is only one attachment point, fuel distribution between tanks is either automated or it is controlled from a control panel at the fuelling point or in the cockpit. As well, a dead man's switch is used to control fuel flow.