New revision 4.8

http://www.physics.byu.edu/research/energy/htm7.html


Excerpt:


"Other explanations for the observations are sought, of course. For example, F. Greening has suggested that aluminum from the planes which struck the Towers could melt, and that this aluminum might fall on "rusted steel surfaces inducing violent thermite explosions." [Greening, 2006] So a few students and I did straightforward experiments by melting aluminum and dropping molten aluminum on pre-heated rusted steel surfaces. There were in fact NO "violent thermite" reactions seen. We observed that the temperature of the molten aluminum in contact with the rusty iron simply cooled at about 25 C per minute (using an infrared probe) until the aluminum solidified, so that any thermite reactions between the aluminum and iron oxide must have been minimal and did not compete with radiative and conductive cooling, thus NOT supporting predictions made by Greening. There was no observable damage or even warping of the steel. (See photograph below.) Nor were violent reactions observed when we dropped molten aluminum onto concrete. [Jones, 2006] These experiments lend no support whatever to the notion that molten aluminum in the WTC Towers could have destroyed the enormous steel columns in the cores of the buildings, even if those columns were rusty and somehow subjected to direct contact with molten aluminum. [See Greening, 2006] We also noted that while the steel pan holding the aluminum glowed red hot, the molten aluminum inside retained its silvery color, adding to the evidence that the molten metal dripping from the South Tower shortly before its collapse was NOT molten aluminum-- besides the fact that the salmon-yellow color of the molten metal (video clip above) implies a temperature too high for the dark-smoke hydrocarbon fires burning in the building. "