Trumpman critique, part 4
This thread's been in quite a few different directions since it started and I don't know whether anyone's still interested (or ever was), but I thought I should just finish off my comments on the Trumpman paper that started all this. After all, the OP asked for comments and suggested that the paper merited serious study. My conclusion, after giving it that study, is: no it doesn't. Here are the last few reasons why not, broken down by section. This covers the last, shorter, sections of the paper.
Discussion on Explosives
This short section begins with an exhortation on the part of the author to the reader to replicate his analysis and conclusions using his data, which is backed up by discussion of features of the collapse which supposedly make this analysis simpler. He proposes three main features of the collapse of WTC1 which simplify such analysis. Of these, the first is that the WTC1 collapse was not "all at once making modeling complex" but floor-by-floor. However, this is fallacious, as conventional bottom-up controlled demolitions result in floor-by-floor collapses. The second is that "a large quantity of explosives" was used, which fallaciously presents Trumpman's conclusion as a starting assumption. The third is that air volume changes in the collapse can be measured accurately because of the smoke from the fire. This is based on the assumption that there is a known and limited degree of mixing between air originating inside the building and air originating outside, an assumption which Trumpman makes no credible attempt to justify. He concludes this section with a quote from Controlled Demolition Inc. about the J. L. Hudson building which refers to the need to pre-weaken structural members too large for commercial shaped charges, which, while supporting his assumption that very large quantities of explosives would be required without such pre-weakening, does nothing to support the credibility of his hypothesis that this was in fact how it was done.
What Explosive Type Used
In another example of non-reasoning to a conclusion, Trumpman lists the melting points of four types of high explosive and states that HMX, the one with the highest melting point (285C) was used to initiate the collapse because "It can survive 270 C+ heat without premature detonation or failure". The significance of 270 C is not discussed anywhere, as Trumpman makes no attempt anywhere in the paper to estimate fire temperatures, quoting only NIST's estimate that some steel members were heated to 500-600 C. The feasibility of using explosives is not therefore established at all.
Where Charges were Placed
Starting with the statement, "I am not a demolition professional but I can point out the obvious", Trumpman asserts that charges were detonated at the connection of the floor trusses to the perimeter wall on the first few floors to collapse, then only in the core as the collapse progressed in order to "keep the collapse centred", and that this would duplicate the truss theory "minus the 'bowed' columns". The inability of Trumpman's hypothesis to replicate this well-documented observation is ignored, unless the placing of the word "bowed" in quotes is intended to cast doubt on the bowing observed. He implies that explosives on the core columns lower down created pools of molten steel at the column foundations, although not only is there doubt that molten metal was observed and no reason to identify any molten metal present as steel, but also high explosives would not produce significant quantities of molten steel as they work by blast overpressure. He implies in an earlier section that thermite might have been placed lower down in the structure but could not be used for the collapse initiation due to timing difficulties; the suggestion that thermite was used, not to initiate the collapse, but to sustain it, where timing would have been even more critical, makes no sense at all.
One paragraph of this section demonstrates a remarkable ignorance of the laws of physics. Trumpman earlier calculated that the collapse of floor 97 was faster than free-fall, and he attempts to explain this measurement by suggesting that the upper section was pulled downwards by the core columns being compromised lower in the building. This would require that the rate of acceleration of an object in free fall was dependent on its mass, a belief disproved by Galileo. He quickly moves on from this gaffe to assert that the upper structure in the collapse would have "slid around randomly during the collapse and toppled off to the side" without detonation of the core columns, again with no attempt at justification. He concludes the section by arguing that the jets of white clouds expelled below the collapse front could only have been explosions, in a self-contradictory line of reasoning that argues that: the material ejected was white smoke, therefore it could not have been smoke from the fires which was black, therefore it must have been due to explosives generating concrete dust, therefore the material ejected was not white smoke.
How Much Explosives Was Used (sic)
Bizarrely, Trumpman begins by arguing that a vastly excessive amount of explosive would be less noticeable than a small amount, based on the assumption that large clouds of smoke are less obvious than small ones. This line of argument would perhaps be more defensible if explosives created no flame or sound. Based on his assumption of limited air mixing, Trumpman calculates that 1.4 tons of HMX were required to create the excess volume of air emitted from floor 97 alone. He makes no attempt to estimate how many floors required a similar amount of explosive or how much would need to be attached to each core column at what interval. However, he includes a comparison with the J. L. Hudson building demolition in which it is stated that nine floors conatined charges, and his calculations appear to assume that the same number of floors contained charges in WTC1. There is no justification given for this assumption, nor is there any speculation on how the charges would need to be placed to cope with uncertainties over the location of the aircraft impact zone. As elsewhere, this section is punctuated by a disjointed rant in which Trumpman reiterates several well-known truth movement canards and attacks the personal integrity of everyone involved in investigations of 9/11.
Concluding remarks on Trumpman's paper
Despite including a number of calculations and extensive data (at least one item of which is wildly incorrect - see part 1) on the WTC1 fires and collapse energies, this paper does not in general make any use of the results of these calculations in reaching its conclusions. Overall, it is instead largely an exercise in proof by assertion, disguised as a scientific paper by the presence of data tables and arithmetic. While this may look impressive on a quick reading, in fact there is no credible evidence of controlled demolition of WTC1 presented here.
Dave