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What is the difference between Jp4 and Jp8

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cherry123

Chemical
Oct 3, 2007
10
Hi,
I need to know about JP4 and JP8 fuels.
They both are made by blending of kero with additives.
Which one is economically better?
 
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Search the ASTM standards for vaiation turbine fuels. Most domestic turbine aircraft use Jet A or Jet A1. The fuel composition for high performance supersonic fighters include components not applicable for domestic aircraft.

You need MIL specifications or oil company contracts for details on JP-4 (jet propellent 4) or JP-8. JP-4 was a kerosine/gasoline blend. JP-8 is a kerosine based fuel with the high altitude additives. You may buy the Air Force specification MIL-DTL-83133E, Turbine fuels, aviation, kerosene types, NATO F-34 (JP-8), and NATO F-35, and JP-8+100. The cost is about $31 USD. I don't know where you will find details on the obsolete JP-4 specification.
 
NAVY MIL-PRF-5624S Turbine fuel, aviation, grades JP-4 and JP-5 , $32 USD.
 
JP4 is wide cut US Air Force/NATO Fuel
typically composed of about 50-60% gasoline and 40-50% kerosene, is highly volatile, and contains hydrocarbons in the C4-C16 range. JP-4 was the primary fuel of the USAF for decades; however, it has been phased out in favor of JP-8 (see below). When specified, it can contain a full additive package including a corrosion inhibitor, anti-icing, and anti-static compounds. An optional additive is a metal deactivator.


JP-8 was developed to be less volatile and explosive than JP-4. (Commercial Jet A-1 fuel is equivalent to JP-8). In 1996, the USAF completed conversion from JP-4 to JP-8 fuel. It contains a full additive package including a corrosion inhibitor, anti-icing, and anti-static compounds. Optional additives are an anti-oxidant and a metal deactivator.

JET A1 primarily differs from JP8 in that its specification ASTM D1655 does not REQUIRE the three additives that are specified and contained in JP8; namely, the Corrosion Inhibitor/Lubricity Enhancer, the Fuel System Icing Inhibitor, and the Static Dissipater Additive.

download this for more JP8 info,



 
MIL-T-5624, Turbine Fuel, Aviation, Grade JP4, JP5, and JP5/
JP8 ST, 1995.
 

I copied sections of an article on the inernet:
Aircraft operators are constantly refining their fuels to deal with specific performance concerns.

The U.S. Air Force during the 1990s switched from JP-4 to JP-8 because it had a higher flashpoint and was less carcinogenic, among other things.

By the mid 1990s, the Air Force further modified JP-8 to include a chemical that reduced the buildup of contaminants in the engines that affected performance.

JP-8 has a strong odor and is oily to the touch, which makes it more unpleasant to handle and less safe in some ways (military personnel who work with it complain that it is difficult to wash off and causes headaches and other physical problems).

About 60 billion gallons (227 billion liters) were used worldwide by the late 1990s, with the U.S. Air Force, Army, and NATO using about 4.5 billion gallons (17 billion liters). It is also used to fuel heaters, stoves, tanks, and other military vehicles.

Commercial jet fuel, known as Jet-A, is pure kerosene and has a flashpoint of 120 degrees Fahrenheit (49 degrees Celsius). It is a high-quality fuel, however, and if it fails the purity and other quality tests for use on jet aircraft, it is sold to other ground-based users with less demanding requirements, like railroad engines. Commercial jet fuel as well as military jet fuel often includes anti-freeze to prevent ice buildup inside the fuel tanks.

 
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