NIST WTC 7 fire simulationSo now we come to some more really fun stuff. Mohr next address the fires in WTC 7, saying that “conspiracists like to show an NYPD photograph of small fires on the north face of Building 7.” His point is not exactly clear, but presumably he means to say that “conspiracy theorists” argue that the fires in WTC 7 were not that significant. Let us stipulate there were very serious fires in WTC 7. Mohr writes, “NIST reported that many fires burned themselves out in 20-40 minutes and then moved on. The fires left behind not only burned out areas, but structurally weakened areas as the beams and columns expanded, sagged, and contracted again.” Okay, so what’s his point? Well, essentially, that fire did the trick of bringing down WTC 7 in the manner in which it came down. The problem with this argument is that it is false.

We’ll come to free-fall shortly, but the fundamental point Mohr fails to address is that NIST’s fire-induced collapse hypothesis requires—bear with me here—that there be fires burning in the northeast corner of the twelfth floor in order to cause the thermal expansion of 13th floor beams, which pushed a girder off of its seat at critical Column 79, causing a series of cascading floor failures that caused Column 79 to buckle and fail due to the lack of lateral support, which led to a progressive series of column failures that resulted in a “global collapse” where the entire structure fell “as a single unit”. Got that? There are numerous problems with this hypothesis, but when it comes to the fires in WTC 7, there’s one problem in particular that stands out, which is that according to NIST’s own analysis of the available photographic and video evidence, the fire on the 12th floor had already burned through the northwest area and had moved on to the western end of the building by the time of its collapse at 5:20 p.m (NCSTAR 1-9 Vol. 1, Chapter 5). So how did NIST deal with this little problem? Simple! They ignored their own evidence and falsified the data they input into their computer model by inserting raging fires in the northeast area of the 12th floor at the time of collapse. Mohr makes no effort to address this fatal flaw in the fire-induced collapse hypothesis or the evidence off scientific fraud on the part of NIST.

Mohr next discusses the fact that BBC reporter Jane Standley announced that WTC 7 had collapsed before it had yet done so and while it was visible still standing right behind her. CNN and Reuters also reported the collapse before it had actually occurred. Mohr addresses this by chalking it up to reporter error and saying, “It is not hard to imagine how such mistakes could be made, especially when there is no time to sift through and analyze fast-moving information.” Fair enough. No doubt, particularly imaginative readers may well be able to come up with a plausible explanation for how a 47-story skyscraper could mistakenly be reported by numerous news agencies to have collapsed before it actually had collapsed.

Mohr next quotes firefighters who said they thought that WTC 7 would collapse due to the debris impact damage it sustained and from the fires. Yet, again, NIST itself acknowledged that the impact damage was neither an initiating nor determinative factor in the collapse, and its own photographic and video evidence showing that the fire had already burned out in the northeast area of the 12th floor is fatal to its fire-induced collapse hypothesis.

Collapse of WTC 7Finally, Mohr comes to the free-fall collapse of WTC 7. He saved the best for last, and we can have some real fun with this one. He notes that NIST acknowledged that WTC 7 “collapsed ‘at gravitational acceleration’ for eight stories over 2.25 seconds.” So how does Mohr deal with free-fall? He offers a convoluted explanation that in part relies on NIST, but which also departs from their findings. This requires a bit of background information and explanation, but briefly: Where he relies upon NIST is their finding that over the first 18 stories, the “global collapse”—that is, the collapse of the entire building “as a single unit”, which occurs after an initial collapse within the core as indicated by the east penthouse falling below the visible roofline—occurred in three stages. However, NIST’s “Stage 1”, the first 1.75 seconds of global collapse, never really happened. What NIST was measuring to create the illusion of a “Stage 1” of collapse was observed movement towards the center of the roofline on the north face of the building, from a video shot from street level and looking upward at the building. After the penthouse begins to descend, movement of the roofline is visible. However, this movement is not indicative of the onset of global collapse, but rather due to the fact that as the core collapsed under the east penthouse, the northern façade was pulled inward. The observed movement of the roofline was not indicative of downward, but of lateral displacement of the roofline. In truth, global collapse began with a sudden onset of free-fall, NIST’s “Stage 2” of collapse. During Stage 3, WTC 7 was at near free-fall as it encountered resistance from the structure below.

Translated into meaningful terms, Mohr effectively argues that as the core columns collapsed, it pulled the perimeter columns inward, so that they “snapped like a stick”, and as each perimeter column “snapped” the load it was carrying shifted to other columns. This all occurred “over about two seconds”, he says, alluding to NIST’s false claim of a 1.75 second “Stage 1” of collapse. Mohr departs from NIST when he comes to the 2.25 seconds of free-fall. He acknowledges that free-fall occurred, but says, “Free-fall collapse speed [sic] does not mean no resistance, it means no net resistance.” What he means is that in addition to the downward force of gravity and the upward force of resistance offered by the load-bearing steel columns, there was also the “variable leveraged downward forces due to connections to other parts of the building.” Got that? So what he is saying is the connections between the perimeter columns and the interior of the building provided a downward force additional to the force of gravity. Got that? So gravity plus the downward force provided by the connections between the perimeter columns and the interior. Thus, according to this argument, if the core of the building was collapsing at the acceleration of gravity, the beams connecting the core to perimeter columns would provide a downward force additional to the force of gravity, so that the perimeter columns would collapse at a rate of acceleration even greater than free-fall. That is to say that the beams were doing work as they collapsed. Of course, Mohr argues that since there was no controlled demolition, the perimeter columns did offer resistance to the collapse, but that the beams connecting the core to the perimeter columns “functioned as levers” providing a force additional to the force of gravity upon the columns, so that the net resistance was zero. If that doesn’t make any sense to you, don’t worry, that’s not an indication that Mohr’s knowledge of physics is vastly superior to yours, but that you just recognize how ridiculous this argument is. Mohr is essentially saying that the building threw itself downward with forces additional to the force of gravity.

So how did the beams do this work? What force was applied to them to cause them to act as “levers”? Where did this energy come from? And a lever requires a fulcrum, so what was the fulcrum in this case? And remember that a lever works by providing force at one end so that it applies force on the other end in the opposite direction. How does a “lever” that is accelerating downward at one end apply a force at the other end so that it accelerates downward at an even greater rate?

Setting aside the asinine nonsense, what does free-fall acceleration actually mean for WTC 7? Turning to Newton’s laws of motion and the law of conservation of energy, what it means is that all of the building’s potential energy was converted to kinetic energy, which means that there was no energy available to do the work of buckling columns (that is, overcoming the resistance of the columns) as required by the fire-induced collapse hypothesis. That is to say that free-fall absolutely disproves the official explanation for the collapse of WTC 7. For free-fall to occur, all of the buildings load-bearing columns had have offered zero resistance to the force of gravity, which means they had to have been cut, and there are no two ways about it.

Mohr ends by asking a bunch of “If … then ….” questions. Most seem directed at the Twin Towers, but addressing those with some relevance also to the collapse of WTC 7:

If 4500 degree nanothermites were used to pulverize almost every inch of every concrete floor, then how could there have been millions of sheets of paper with an ignition temperature of only 451° raining down on the sidewalks?

This is a strawman argument. To my knowledge, nobody has suggested that nano-thermite was used “to pulverize almost every inch of every concrete floor”. To bring the building down, the steel load-bearing columns would have to be cut and gravity would do the rest. No nano-thermite or explosives would be used on the floors at all. Any use of nano-thermite would be targeted at the connections or the columns themselves.

If 4500 degree nanothermites were used extensively even at the top to cause a supposed upward explosion, then why were first responders able to walk over the wreckage less than an hour after the Tower collapses?

This refers to the Twin Towers and not WTC 7, but it should be noted that the debris was so hot in some places that the soles of workers’ boots melted and steel toes would heat up to unbearable temperatures. Doh!

If there were 2800 degree rivers of molten steel in the debris, then why do NASA thermal images show maximum temperatures in the rubble of only 1400°?

NASA’s thermal images only recorded surface temperatures, implying significantly higher temperatures under the debris. Mohr doesn’t mention it, but there are also numerous credible eyewitness reports as well as photographic evidence of molten steel in the debris piles. And, as Mohr already acknowledged, samples of steel that had been melted were in fact recovered from the debris.

If the debris pile had 2800 degree temperatures, then why were firefighters able to pour millions of gallons of water all over it and not trigger the deadly thermal explosions that are caused when water comes in contact with molten steel or iron?

In fact, firefighters did have to take care in their efforts because there was indeed a danger “that applying water to cool the steel could cause a steam explosion that would propel nearby objects with deadly force”, as the U.S. Department of Labor’s Occupational Safety & Health Administration noted in a report on the dangers of the Ground Zero worksite. Doh! The real question is: How, if firefighters poured millions of gallons of water, as well as the chemical fire suppressant Pyrocool, in addition to several rainfalls, did fires continue to burn within the debris piles for months?

If the lateral ejection of beams were caused by explosive nanothermites, then there would have been deafening 140 db sounds that can’t be muffled by more than a few db or you lose the explosive force of the shock wave itself.

This is again with reference to the Twin Towers, but still relevant, if nano-thermite was used in WTC 7. Mohr offers no source for his claim that nano-thermite would create “deafening 140 db sounds” when ignited. But the clue here is his reference to “the explosive force of the shock wave itself”. With conventional explosives used in controlled demolitions, like RDX, it is the pressure of the explosion that cuts through steel columns. With thermitic materials, however, it isn’t a high-pressure “shock wave”, but the exothermic reaction that melts through the steel. One patented device designed to employ thermitic materials for applications including demolition notes that a “primary disadvantage” of conventional demolition charges “is that they generate excessive noise and debris upon detonation”, while “Thermite-based cutting devises which employ a cutting flame produce relatively little over pressure.” While regular thermite is an incendiary, as the Department of Defense points out, nano-thermite has the potential for uses in “high-power, high-energy composite explosives”. But nano-thermite is “explosive” because of the great amount of energy it releases, not via high pressure “shock waves”, but via the even more energetic and more rapid exothermic reaction compared to regular thermite.

If there had been large explosions prior to the collapse, then they would have been a part of the seismic record, and they were not.

This is a non-sequitur. Mohr repeats the same fallacy, apparently assuming thermitic materials would “explode” in the sense that they would create a high-pressure “shock wave”. If conventional explosives were also used in conjunction with thermite, fewer would be required. And the fact is that there were explosions taking place that were documented on video. Many eyewitnesses reported explosions, explosions were captured on the audio of a number of videos, news reporters talked about explosions taking place well after the collapse of the Twin Towers, and there was speculation by some reporters live on air that these were cars exploding after having caught fire as a result of the collapses. It may be that there was some other such source of the explosions, but one can hardly deny that they took place. Two distinct explosions can be heard in the audio track of one video of WTC 7 immediately prior to the observable collapse of the east penthouse.