2. Aviation Fuels
Jet Fuel is a type of aviation fuel designed for use in aircraft powered by gas-turbine engines. The most common fuels are Jet A and Jet A-1 which are produced to an internationally standardized set of specifications. The only other jet fuel that is commonly used in civilian turbine engine-powered aviation is called Jet B and is used for its enhanced cold-weather performance. Kerosene-type jet fuel (including Jet A and Jet A-1) has a carbon number distribution between about 8 and 16 carbon numbers; wide-cut jet fuel (including Jet B), between about 5 and 15 carbon numbers.
Jet A-1 (NATO Code F35, DEF STAN 91 - 91. JSD AVTUR) is a kerosene grade of fuel suitable for most turbine engined aircraft. It has a flash point minimum of 38 degrees C (100°F) and a freeze point maximum of -47 degrees C. It is widely available outside the U.S.A. The main specifications for Jet A-1 grade are the UK specification DEF STAN 91-91 (Jet A-1) NATO code F-35, (formerly DERD 2494) and the ASTM specification D1655 (JetA-1).
Jet A is the standard jet fuel type in the United States since the 1950s and is only available there. Jet A is similar to Jet-A1, except for its higher freezing point of −40 °C (vs. −47 °C for Jet A-1). Like Jet A-1, Jet A has a fairly high flash point of 38 °C (100 °F), with an auto-ignition temperature of 210 °C (410 °F). The US commercial fuels are not required by law to contain antistatic additives, and generally do not. Jet A is used for almost all commercial aviation flights within or originating from the United States. The annual U.S. usage of jet fuel was 21 billion gallons (80 billion liters) in 2006.
Jet B is a wide-cut type fuel in the naphtha-kerosene region that is used for its enhanced cold-weather performance. It is a distillate covering the naphtha and kerosene fractions, however, Jet B's lighter composition; higher flammability, makes it more dangerous to handle. It can be used as an alternative to Jet A-1, but it is thus restricted only to areas where its cold-weather characteristics are absolutely necessary. ASTM has a specification for Jet B but in Canada it is supplied against the Canadian Specification CAN/CGSB 3.23.
JP stands for Jet Propulsion. Military facilities around the world use a different classification system of JP (Jet Propulsion) numbers.The governments of many countries maintain separate specifications for jet fuel for military use.
The reasons for separate specifications include the operational and logistical differences between the military and civilian systems and the additional demands high-performance jet fighter engines place on the fuel.