For reasons of inter-operational ability, British and United States military standards are harmonized to a degree. The British Ministry of Defence establishes standards for both civil and military jet fuels. Department of Defense produces standards for military use.
In the United States, ASTM International produces standards for civilian fuel types, and the U.S. Higher flash point products required for use on aircraft carriers are more expensive to produce. Very low temperature freezing points reduce the availability of fuel. Over the subsequent years, details of specifications were adjusted, such as minimum freezing point, to balance performance requirements and availability of fuels. British standards derived from standards for kerosene use for lamps-known as paraffin in the UK-whereas American standards derived from aviation gasoline practices.
Both British and American standards for jet fuels were first established at the end of World War II.
Most jet fuels in use since the end of World War II are kerosene-based. Other fuels used were kerosene or kerosene and gasoline mixtures. Gasoline was a third option but unattractive due to high fuel consumption. The first axial compressor jet engine in widespread production and combat service, the Junkers Jumo 004 used on the Messerschmitt Me 262A fighter and the Arado Ar 234B jet recon-bomber, burned either a special synthetic "J2" fuel or diesel fuel. Jet and gas turbine ( turboprop, helicopter) aircraft engines typically use lower cost fuels with higher flash points, which are less flammable and therefore safer to transport and handle. Turbine engines (like diesel engines) can operate with a wide range of fuels because fuel is injected into the hot combustion chamber. 3.3 Typical physical properties for Jet A and Jet A-1įuel for piston-engine powered aircraft (usually a high- octane gasoline known as avgas) has a high volatility to improve its carburetion characteristics and high autoignition temperature to prevent preignition in high compression aircraft engines.3.2 Differences between Jet A and Jet A-1.Kerosene-type jet fuel (including Jet A and Jet A-1, JP-5, and JP-8) has a carbon number distribution between about 8 and 16 (carbon atoms per molecule) wide-cut or naphtha-type jet fuel (including Jet B and JP-4), between about 5 and 15. Furthermore, the range of molecular mass between hydrocarbons (or different carbon numbers) is defined by the requirements for the product, such as the freezing point or smoke point. Jet fuel is therefore defined as a performance specification rather than a chemical compound. Because the exact composition of jet fuel varies widely based on petroleum source, it is impossible to define jet fuel as a ratio of specific hydrocarbons. Jet fuel is a mixture of a variety of hydrocarbons. The only other jet fuel commonly used in civilian turbine-engine powered aviation is Jet B, which is used for its enhanced cold-weather performance. The most commonly used fuels for commercial aviation are Jet A and Jet A-1, which are produced to a standardized international specification.
It is colorless to straw-colored in appearance. Jet fuel or aviation turbine fuel ( ATF, also abbreviated avtur) is a type of aviation fuel designed for use in aircraft powered by gas-turbine engines.
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