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ME Petroleum are an oil trading company. They have a page of Jet Fuel facts, where they explain that the standard specification of Jet Fuel is JET A-1 (a.k.a JET A).

They also claim the "Maximum burning temperature" of Jet A-1 fuel is 980 °C.

(While this page doesn't make any claims about 9/11, this page is frequently cited by 9-11 conspiracy theorists; it is used to argue that jet fuel could not have burned hot enough to weaken the steel structures of the World Trade Center towers. Whether that is true or not is outside the scope of this question.)

The question is whether jet fuel burns at a higher temperature than the one given.

(I suspect that, in context, the page is actually referring to the maximum operating temperature that a jet engine should have for the fuel to retain the properties required to operate the engine, rather than the maximum temperature that an uncontrolled fire involving the fuel can reach, but I would like some definite information on this subject.)

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    Well, they are wrong in that the open air burn temperature IS higher (1030 degree celsius en.wikipedia.org/wiki/… ) It also isn't necessary for the fire to "melt" the steel because steel weakens at much lower temperatures than it melts. – JRE Jan 29 '16 at 10:10
  • Perhaps the question can be reworded to ask "Is the maximum burning temperature of jet fuel 980 C?", as stated by the reference. The cited reference is clearly wrong, as several other references show. It might help clear up a common myth among conspiracy theorists. – Mark Jan 29 '16 at 14:09
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    @Mark I asked what the reference does mean, on the assumption that the page is correct but that "maximum burning temperature" is a specialist industry term that does not mean what the conspiracy theorists think it means, but instead means something like you void the warranty by burning it hotter than that. – Random832 Jan 29 '16 at 16:45
  • @Random832 I was trying to look into the same thing. I found this which explains that "maximum combustion temperature" is often lower, and occassionally higher, than adiabatic temperature, and it defines adiabatic temperature clearly, but it doesn't define "maximum combustion temperature" itself that I can see – user56reinstatemonica8 Jan 29 '16 at 16:56
  • @Random832 - I've searched for the term and can't find any reference to what it means. Most of the results seem to point to 9/11 conspiracy sites, presumably because they reference the site you pointed to. – Mark Jan 29 '16 at 16:57
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No. The link is to an oil trading company, not a technical source, and the reference provides no source for the information.

"Maximum burning temperature", is not a standard measure for specifying jet fuel. Jet fuel specifications from ExxonMobil list many requirements and test methods, but do not mention "maximum combustion temperature", or any similar property.

The highest temperature attainable when burning a fuel is known as the "Adiabatic flame temperature". Wikipedia provides a very good explanation, including:

The constant pressure adiabatic flame temperature is the temperature that results from a complete combustion process that occurs without any heat transfer or changes in kinetic or potential energy.

Based on the article, the reported maximum flame temperature of 980 °C is much too low, because

In daily life, the vast majority of flames one encounters are those of organic compounds including wood, wax, fat, common plastics, propane, and gasoline. The constant-pressure adiabatic flame temperature of such substances in air is in a relatively narrow range around 1950 °C.

The Wikipedia article on jet fuel gives an adiabatic flame temperature of 2,230 °C.

A source referenced in the Wikipedia article gives a value of 2300 K (2030 °C).

The maximum adiabatic flame temperature occurs when the air to fuel ratio is exactly right for complete combustion of the fuel - enough oxygen to completely burn the fuel with none leftover. This is called stoichiometric conditions, or zero excess air. In a large, uncontrolled fire within an enclosed space, it is expected that there will be some regions where the air to fuel ratio is higher and others where it is lower than stoichiometric conditions, and in between these there will be some regions with perfect stoichiometry. Therefore temperatures will not be uniform, but some regions may be very close to the stoichiometric flame temperature.

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