Jet+Fuel

=JET FUEL:=

Jet fuel is a type of aviation fuel designed for use in aircraft powered by gas turbine engines. It is clear to straw-colored in appearance. The most commonly used fuels for commercial aviation are Jet A and Jet A-1 which are produced to a standardized international specification. 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. Jet fuel is a mixture of a large number of different hydrocarbons. The range of their sizes (molecular weights or carbon numbers) is restricted by the requirements for the product, for example, the freezing point or smoke point. Kerosene-type jet fuel (including Jet A and Jet A-1) has a carbon number distribution between about 8 and 16 carbon numbers (carbon atoms per molecule); wide-cut or naphtha-type jet fuel (including Jet B), between about 5 and 15 carbon numbers Jet fuel must be free of water contamination because if it freezes during flight due to condensation in the jet and in fuel inlet pipes. This was the cause of a British Airways accident in the past.

Differences between Jet A and Jet A-1
[|Shell] Jet A-1 refueller truck on the ramp at [|Vancouver International Airport]. Notice the signs indicating 1863 hazardous material and JET A-1. A [|US Airways] [|Boeing 757] being fueled at [|Fort Lauderdale – Hollywood International Airport].

Jet A specification fuel has been used in the United States since the 1950s and is only available in the United States (and at Gander Airport in Newfoundland by Shell Aviation), whereas Jet A-1 is the standard specification fuel used in the rest of the world. Both Jet A and Jet A-1 have a flash point higher than 38 °C (100 °F), with an autoignition temperature of 210 °C (410 °F). This means that the fuel is safer to handle than traditional avgas.

The primary differences between Jet A and Jet A-1 are the higher freezing point of Jet A (−40 °C vs −47 °C for Jet A-1), and the mandatory requirement for the addition of an anti-static additive to Jet A-1.

Like Jet A-1, Jet A can be identified in trucks and storage facilities by the UN number 1863 Hazardous Material placards.[3] Jet A trucks, storage tanks, and pipes that carry Jet A are marked with a black sticker with a white "Jet A" written over it, next to another black stripe.

The annual U.S. usage of jet fuel was 20.2 billion US gallons (7.6×1010 L) in 2009.[4]

Typical physical properties for Jet A and Jet A-1 Jet A-1 Fuel must meet the specification for DEF STAN 91-91 (Jet A-1), ASTM specification D1655 (Jet A-1) and IATA Guidance Material (Kerosene Type), NATO Code F-35.

Jet A Fuel must reach ASTM specification D1655 (Jet A) [5]

Typical physical properties for Jet A / Jet A-1 fuel:[6][dead link]


 * ||= **Jet A-1** || **Jet A** ||
 * ** [|Flash point] ** || 42 °C || 51.1 °C ||
 * ** [|Autoignition temperature] ** ||||= 210 °C (410 °F) [|[7]] ||
 * ** [|Freezing point] ** || −47 °C (−52.6 °F) || −40 °C (−40 °F) ||
 * ** [|Open air burning] temperatures** ||||= 260-315 °C (500-599 °F) [|[7]] ||
 * ** [|Density] at 15 °C (59 °F)** || .804 kg/L || .820 kg/L ||
 * ** [|Specific energy] ** || [|43.15] [|MJ] /kg || [|43.02] [|MJ] /kg ||
 * ** [|Energy density] ** || 34.7 MJ/L || 35.3 MJ/L ||

Jet B
Jet B is a fuel in the [|naphtha] - [|kerosene] region that is used for its enhanced cold-weather performance. However, Jet B's lighter composition makes it more dangerous to handle. [|[5]] For this reason it is rarely used, except in very cold climates. A blend of approximately 30% kerosene and 70% gasoline, it is known as wide-cut fuel. It has a very low freezing point of - 60 degrees Celsius and a low flash point as well. It is primarily used in US and some military aircraft.

Water in jet fuel
It is very important that jet fuel be free from water contamination. During flight, the temperature of the fuel in the tanks decreases, due to the low temperatures in the upper atmosphere. This causes precipitation of the dissolved water from the fuel. The separated water then drops to the bottom of the tank, because it is denser than the fuel. From this time on, as the water is no longer in solution, it can freeze, blocking fuel inlet pipes. This was the cause of the British Airways Flight 38 accident. Removing all water from fuel is impractical, therefore fuel heaters are usually used on commercial aircraft to prevent water in fuel from freezing.

There are several methods for detecting water in jet fuel. A visual check may detect high concentrations of suspended water, as this will cause the fuel to become hazy in appearance. An industry standard chemical test for the detection of free water in jet fuel uses a water-sensitive filter pad that turns green if the fuel exceeds the specification limit of 30ppm (parts per million) free water