Dr. Graeme MacQueen, "Eyewitness Evidence of Explosions in the Twin Towers : Testimony for the Toronto Hearings, Day 3, Sept. 10, 2011" (without appendix).
(This article, which is Copyright © Graeme MacQueen and used here with permission, is an earlier version of the paper that later appears in the book, The 9/11 Toronto Report, edited by James R. Gourley, pp. 171 - 191. Our interview with Dr. MacQueen on this subject can be heard here: TMR 115 : Dr. Graeme MacQueen : Eyewitness Evidence of Explosions in the Twin Towers)
Eyewitness Evidence of Explosions in the Twin Towers
Testimony for the Toronto Hearings, Day 3, Sept. 10, 2011
Many of us are convinced that the Twin Towers of the World Trade Center were brought down on September 11, 2001 through controlled demolition. But the question at once arises: if this is what happened, would somebody not have noticed?
The answer is that many people did notice. There is a good deal of eyewitness evidence for the demolition of buildings 1 and 2. In this paper I will give a brief overview of this evidence.
But first let me raise one of the commonest objections I confront when presenting this material. Eyewitness evidence, say the objectors, is “soft,” untrustworthy, unreliable. According to such critics it does not matter how many eyewitnesses there are to an event or who these eyewitnesses are or how their accounts relate to each other: the best plan is just to dismiss everything they say. This is an odd view. I do not find support for it either in social scientific studies of eyewitness testimony or in the scholarly literature on criminal investigation.  Eyewitness evidence certainly has its vulnerabilities: we know that eyewitnesses can misperceive, misremember and deceive. But, as with other kinds of evidence, we have developed ways of checking to see if what the witnesses report is accurate. For example, we look for corroborating evidence—further eyewitness evidence as well as evidence of entirely different kinds.
Is eyewitness evidence relevant to the investigation of explosions? The National Fire Protection Association’s manual on fire and explosion investigations states clearly that in an explosion investigation, “the investigator should take into consideration all the available information, including witness statements.” 
In any case, my paper has been written largely as a critique of the handling of eyewitness evidence of explosions by the 9/11 Commission and the National Institute of Standards and Technology. Both of these organizations make extensive use of eyewitness evidence and evidently consider it valid and important. When I disagree with NIST and the 9/11 Commission on eyewitness testimony, therefore, I do so not at the level of principle but at the level of application.
Now I would like to say a few words about my previous work on this subject.
In early 2006 I learned about the oral histories of the Fire Department of New York (technically, World Trade Center Task Force Interviews) through a fine article by David Ray Griffin.  These oral histories had been released in 2005 by the City of New York not long before Griffin’s article was written. The New York Times had taken the city to court to obtain the release of the documents, and when the material was released the newspaper hosted the oral histories in the form of a series of separate pdf files on its website. When I began reading these documents they had been studied closely by very few people.
The oral histories were collected by the World Trade Center Task Force of the FDNY after New York City fire commissioner Thomas Von Essen decided it would be important to have a record of what the members of the department experienced on that day. The Task Force interviews comprise 10-12,000 pages of statements by approximately 500 “FDNY firefighters, emergency medical technicians and paramedics collected from early October, 2001 to late January, 2002.” 
Professor Griffin, with the help of able researchers, had ferreted out fascinating descriptions of explosions from this material. I decided to read the texts for myself and see what I could find. The results were published in 2006 as the article, “118 Witnesses: the Firefighters’ Testimony to Explosions in the Twin Towers.” 
In this paper I will build on that earlier work. I am able to refine the analysis somewhat and to expand the list of eyewitnesses. My confidence in the method and the conclusions has grown in the years since that earlier study.
As I review this evidence for you I want to make three main points:
- The conviction that the Towers came down because of explosions was common on 9/11.
- There is substantial eyewitness evidence supporting this conviction.
- This evidence has been ignored or suppressed by both the 9/11 commission and NIST.
(1) The explosion hypothesis was common on 9/11
In discussions of the events of 9/11 it is often implied that the original, obvious, and natural hypothesis concerning the destruction of the Twin Towers is some variety of gravity-driven collapse. It was obvious to everyone on 9/11, we are led to believe, that the Towers came down because the buildings simply could not withstand the plane strikes and subsequent fires and therefore gave way. We who say the buildings came down because of explosions—we who hold to an “explosion hypothesis” in the broad sense--are, according to this view, late arrivals. We are folks who came along after 9/11 and over-thought an initially simple situation due to our conspiratorial mind-set.
It is easy to prove that this is a falsification of history. Proponents of the explosion hypothesis were extremely common on 9/11, especially at the scene of the crime, and I have not found the slightest evidence to suggest that they had a special conspiratorial way of thinking. Many made their judgment on the basis of what they directly perceived while close to the buildings. Some accepted as a matter of course that complete and energetic pulverization of these enormous buildings such as took place must have entailed explosions.
I will give five cases to support my claim.
(i) In a video clip preserved from 9/11, ABC television reporter N. J. Burkett is seen standing close to the Twin Towers. He draws our attention to the firefighters at the scene and to the burning buildings themselves. Suddenly, the South Tower begins to come apart behind him. As the pulverized debris shoots into the air, Burkett says: “A huge explosion now, raining debris on all of us. We better get out of the way!” 
I see no evidence that Mr. Burkett was over-thinking the situation or had a conspiratorial mind-set. He certainly did not come along after 9/11: he expressed his judgement before the debris of the building had even reached the ground. Then he ran for his life. Half an hour later he would run for his life again as the North Tower came down. 
(ii) If we watch CNN’s same-day coverage of the events of 9/11 we will find Mayor Giuliani being asked questions about explosions in the Twin Towers on two separate occasions.
The second occasion is a press conference at about 2:39 p.m. A female reporter (off screen) asks the Mayor: “Do you know anything about the cause of the explosions that brought the two buildings down? Was it caused by the planes or by something else?” 
Notice that she does not ask if there were explosions: she assumes there were. She does not ask if these explosions brought down the Towers: she assumes they did. She merely wants to know what caused the explosions—the planes or “something else?”
(iii) In footage known as the “Matthew Shapoff video,” acquired from NIST through a FOIA request, we discover several people (off screen) chatting while they watch the events at the World Trade Center unfold at a distance and film them with their video camera. Suddenly, through their camera we see the North Tower begin to throw forth pulverized debris in all directions in huge plumes as it disintegrates. After a horrified, “oh, my God!” we hear a male voice, presumably that of Shapoff, utter three interesting lines: “That was a bomb that did that! That was a fuckin’ bomb that did that! There’s no goddamn way that could have happened!” 
Again I find no evidence that the witness was indulging in conspiratorial thinking: Shapoff gave his spontaneous as the debris from the building was just reaching the ground.
(iv) New York firefighter Christopher Fenyo, in a passage from the World Trade Center Task Force interviews, provides my fourth example.
Fenyo speaks of a debate that began among firefighters who on the scene. The debate started after the destruction of the South Tower but before the destruction of the North Tower—in other words, roughly between 10:00 and 10:30 a.m.
“...At that point a debate began to rage because the perception was that the building looked like it had been taken out with charges.” 
As with Shapoff, the statement concerns not just explosions generally but the intentional destruction of the building with explosives. That is, people were already debating a sub-category of the explosion hypothesis, the controlled demolition hypothesis, before 10:30 on the morning of 9/11.
(v) My fifth and final example refers to the FBI. The FBI’s name for its investigation of the 9/11 incidents is PENTTBOM, which stands for “Pentagon/Twin Towers Bombing Investigation.” Is it possible that when this name was assigned someone in the FBI thought a bombing had taken place? (Recall that according to the current official narrative there was no bombing at any of the affected locations.) If we scan the television coverage on the day of 9/11 we find USA Today’s foreign correspondent Jack Kelley telling his TV audience that the FBI’s “working theory” at that time in the day was that “at the same time two planes hit the building…there was a car or truck packed with explosives underneath the building, which exploded at the same time and brought both of them down.”  Given that Kelley was later shown to have routinely fabricated stories for USA Today, his allegations about the FBI would have to be corroborated. However, the general hypothesis ascribed here to the FBI—the buildings were brought down through the use of explosives--was common on 9/11. For example, Albert Turi, FDNY Chief of Safety, told NBC’s Pat Dawson not long after the destruction of the Towers that “according to his theory he thinks that there were actually devices that were planted in the building” (Dawson’s summary). 
These five examples have been offered in support of my claim that the explosion theory, even in its most robust form (deliberate destruction through explosives), was familiar on 9/11. It was widely accepted as a reasonable theory. That many people held this theory does not mean it is correct, but it suggests is that if this theory is to be rejected it must be rejected on the basis of evidence, not because it is regarded as late, unnatural, exotic or conspiratorial.
(2) There is strong eyewitness evidence supporting the explosion hypothesis.
What is the eyewitness evidence for explosions in the Twin Towers? What is its nature and how strong is it?
I wish to divide this discussion into two sections, which will address quality and quantity. Under quality I will present several cases that show eyewitnesses providing richly detailed accounts of what they witnessed. During this discussion I will introduce the issue of corroboration and will also have the opportunity to address the suppression of the explosion hypothesis. When I turn to the issue of quantity I will try to give an idea of the number and variety of eyewitnesses who discuss explosions in their statements.
I will give three main examples of richly detailed accounts.
(a) I begin with two firefighters, Dennis Tardio and Pat Zoda, whose conversation about the destruction of the North Tower was captured on film by the Naudet brothers on the day of 9/11. 
Tardio and Zoda repeatedly affirm each other’s accounts, both with words and with hand gestures. The hand gestures are like a series of karate chops starting high and going quickly downward. The witnesses evidently want to suggest that there were many discrete, energetic events that they observed, and that these started high up and then moved rapidly down the building at regular intervals.
Zoda says, as he moves his hand: “Floor by floor, it started poppin’ out.” Tardio concurs and uses the same hand gesture: “It was as if they had detonated, detonated (Zoda: “Yeah, detonated, yeah”), you know, as if they were planted to take down a building: boom, boom, boom, boom, boom, boom, boom.” Zoda adds: “All the way down. I was watching and running.”
Remember: these are firefighters and they are used to encountering the standard sorts of explosions that occur in building fires. But they do not talk about smoke explosions, or “boiling-liquid-expanding-vapour” (BLEVE) explosions, or any of the other expected forms of explosion. They are talking about, and acting out with dramatic gestures, a different thing altogether. They say that what they saw resembled a controlled demolition.
(b) I move next to set designer Paul Lemos, who was, on 9/11, in the vicinity of the World Trade Center to participate in the filming of a commercial. Lemos was caught on videotape on 9/11 near the Trade Center--we can see Building 7 still standing in the distance.  He was filmed by a different film maker at a different location than the firefighters just described, and as far as I can discover this video is entirely independent of the one just discussed. Yet the first thing we notice when Lemos begins describing the demise of the North Tower is that he uses the same hand gestures as Tardio and Zoda: rapid chops that start high and move at regular intervals down the building.
Here is what he says as he performs his gestures:
“All of a sudden I looked up and about twenty stories below…the fire…I saw, from the corner, boom, boom, boom, boom, boom, boom, boom, boom, boom…just like twenty straight hits, just went down and then I just saw the whole building just went ‘pshew’…and as the bombs were goin’ people just started running and I sat there and watched a few of ‘em explode and then I just turned around and I just started running for my life because at that point the World Trade Center was coming right down…”
Lemos, bolder than the firefighters, does not protect himself by saying “as if they had detonated.” He refers openly to “bombs” and he says he watched them “explode.”
Before I get to the issue of corroboration I wish to refer to another part of the Lemos footage. I may seem to be digressing but the point is actually very important to the issue of the suppression of the explosion hypothesis.
Lemos tells us that while he was near the scene he got into a conversation with an architect brought onto the scene by the authorities. This architect told him he had not perceived explosions. (“…now, they told me afterwards it wasn’t explosions. I was talking to one of the architects that they pulled in.”) How remarkable! Regardless of whether or not this “architect” had a sinister purpose, we can be sure of the following facts: (1) unlike Lemos, he was not himself an eyewitness (he had been “pulled in” to the scene); (2) he would not have had time to carry out a thorough canvassing of eyewitnesses; (3) he certainly did not have time to do a comprehensive review of photographs and videos of the collapse; and (4) there is little possibility he could have studied the remains of the building in any detail—either the steel or the dust. Despite this he feels he can tell an eyewitness what that eyewitness did not perceive. Not only is this an unjustified judgment, it is extremely irregular in so far as it diminishes the possibility of an unbiased investigation. Whether we are thinking of a homicide investigation, a fire investigation or an explosion investigation, each process has strict principles and in each case it would be unheard of to walk onto a crime scene and taint the evidence by interfering with an eyewitness.
I have discussed this point because of its wider significance. It is clear that in the months following 9/11 many eyewitnesses muted, qualified and even rejected their own initial judgments after hearing that authorities had adopted a structural failure hypothesis that had no room for explosions. The structural failure hypothesis that was most common during that period, and that was widely advanced as correct, was the “pancake” hypothesis of sequentially failing floors. The pancake hypothesis has since that time been discredited and abandoned--it now has no status with NIST or any other serious investigator—but in the early days it did a fine job of weakening the confidence of eyewitnesses who thought they had perceived explosions.
Examples of firefighters revising their judgment of what they had perceived on the basis of what authorities were saying at the time are common in the World Trade Center Task Force interviews.
Dominick DeRubbio says in his description of the destruction of the South Tower: “It was weird how it started to come down. It looked like it was a timed explosion, but I guess it was just the floors starting to pancake one on top of the other.” 
James Drury, also of the FDNY, says in his statement about the North Tower: “...we started to hear the second roar. That was the north tower now coming down. I should say that people in the street and myself included thought that the roar was so loud that…bombs were going off inside the building. Obviously we were later proved wrong…” 
And John Coyle, FDNY, starts his important statement about the South Tower in a very tentative way: “The tower was--it looked to me--I thought it was exploding, actually. That’s what I thought for hours afterwards…Everybody I think at that point still thought these things were blown up.” 
Everybody thought the Towers were blown up? We see here how common the explosive demolition theory was on 9/11. And we begin to see how the explosion hypothesis was marginalized—not by sound science but by speculative theories given a stamp of approval by authority figures.
Let us return to the discussion of quality and detail in eyewitness accounts. I have used two videos to demonstrate quality. Tardio and Zoda, as well as Lemos, are not speaking of hearing vague booms somewhere: they are giving quite precise descriptions of an event that they both heard and saw. They do not describe a standard controlled demolition. They describe a building being torn apart from high up near the airplane impact down its length, in a manner that would be unusual for a controlled demolition but that would make sense in a covert operation where the demolition is being disguised as gravity collapse.
Notice the corroboration that we have. Tardio, Zoda and Lemos give very similar descriptions of what they perceive. I have drawn attention to their identical hand gestures, especially, to make this point.
Before going on to my third example of a high quality witness statement, let me ask the question: Are there additional sources that corroborate the descriptions of regular, descending energetic events given by Zoda, Tardio and Lemos? Let us begin with corroboration through evidence of the same kind—in other words, further eyewitness evidence. Are there other eyewitnesses who further corroborate the descriptions given by Tadio, Zoda and Lemos? Yes. Here are three examples.
Ross Milanytch, an employee at nearby Chase Manhattan Bank, says of the South Tower:
"It started exploding...It was about the 70th floor. And each second another floor exploded out for about eight floors, before the cloud obscured it all." 
John Bussey, a reporter for the Wall Street Journal, said this of the South Tower:
“Off the phone, and collecting my thoughts for the next report, I heard metalic crashes and looked up out of the office window to see what seemed like perfectly synchronized explosions coming from each floor, spewing glass and metal outward. One after the other, from top to bottom, with a fraction of a second between, the floors blew to pieces.” 
Kenneth Rogers of the New York Fire Department said this about his experience with the South Tower:
“...we were standing there with about five companies and we were just waiting for our assignment and then there was an explosion in the south tower… A lot of guys left at that point. I kept watching. Floor after floor after floor. One floor under another after another and when it hit about the fifth floor, I figured it was a bomb, because it looked like a synchronized deliberate kind of thing.” 
We have been looking at eyewitness evidence that corroborates other eyewitness evidence. But corroboration can be even more impressive when it involves an entirely different form of evidence. Paul Lemos explicitly says that he was watching the North Tower, and, more specifically, a corner of the North Tower, when he saw the explosions. Do we have good quality video footage of a corner of the North Tower taken during its destruction? We do.  And when we look at it we see quite clearly a rapid sequence of forceful and focused ejections, apparently explosive, moving down the building. The size and velocity of these ejections can be measured: their existence and basic characteristics are not open to question. I will leave to one side here the explanations that the National Institute of Standards and Technology has formulated to account for these ejections, as I will also leave to one side the criticism--to my mind, definitive--of NIST’s attempts. 
(c) I turn now to the third eyewitness whose statements I wish to use as an example of detailed, high quality testimony.
Here I adopt a different approach. Some who object to my compilations of eyewitness testimony say that what these witnesses experienced may not have been explosions at all. Falling bodies, crashing elevators, snapping columns and even sonic booms have all been proposed as alternative explanations. I shall take up this challenge by analyzing quite closely the statements of a particular eyewitness.
The witness is Sue Keane. She was, on 9/11, an officer in the Port Authority Police Department where she had been for eight years. Before this she had spent 13 years in the U.S. Army, where she received training on how to respond to explosions.
I have listed below six common characteristics of explosions as described by former FBI explosives expert James Thurman in his book, Practical Bomb Scene Investigation.  I have matched them to selections from Sue Keane’s statements as given to the authors of the book, Women at Ground Zero.  These statements, given within a few months of the 9/11 events, are supported by her separate handwritten submission to the Port Authority Police Department.
Keane: “A couple of minutes later, it sounded like bombs going off. That’s when the explosions happened.”
(ii) Positive blast pressure phase
“The windows blew in...we all got thrown.” “Each one of those explosions picked me up and threw me.”
(iii) Partial vacuum during positive blast pressure phase
“There was this incredible rush of air, and it literally sucked the breath out of my lungs.”
(iv) Negative blast pressure phase
“Everything went out of me with this massive wind...Stuff was just flying past. Then it stopped and got really quiet, and then everything came back at us. I could breathe at this point, but now I was sucking all that stuff in, too. It was almost like a back draft. It sounded like a tornado.”
(v) Incendiary or thermal effect
“...he threw me under the hose, which in a way felt great, because I didn’t realize until then that my skin was actually burning. I had burn marks, not like you’d have from a fire, but my face was all red, my chest was red.”
(vi) Fragmentation and shrapnel
“...there was stuff coming out of my body like you wouldn’t believe. It was like shrapnel. It’s still coming out.”
I have found no evidence that Keane was led or pressured by her interviewers or that her accounts have been tampered with. The handwritten PAPD report of this brave and obviously traumatised individual, which corroborates the above account in several crucial respects, is directly available in the PAPD documents released in 2003.  I give a page of that report here:
What should we conclude about Sue Keane? I conclude that she experienced exactly what she said she experienced: massive explosions. On what reasonable grounds can we exclude her witness statements as we attempt to determine the causes of the destruction of the Twin Towers?
I have concentrated in this section on three sets of witnesses as examples of “quality,” meaning evidence that is rich and gives a good deal of important detail.
Let us now turn to the issue of quantity.
How many eyewitnesses are there who speak of, or imply, explosions near the time of the destruction of the Twin Towers?
I know of no complete count. There is no evidence that the FBI, or the 9/11 Commission, or the National Institute of Standards and Technology attempted a count. Although my own list is woefully incomplete, I offer in the Appendix of this paper a list of 156 witnesses. Let us look at two graphs that I have constructed to summarize certain aspects of the list. First: who are these witnesses?
Witnesses by profession/agency
Of the 156 eyewitnesses, 121 are from the Fire Department of New York. Another 14 witnesses are from the Port Authority Police Department. Thirteen are reporters, most of them working for major television networks, and eight are listed as “other”—most are civilians who worked in the vicinity of the Towers.
Members of the FDNY and PAPD are what we call “first responders.” So 135 out of 156 witnesses, or 87% of the total, are first responders. This is significant because these people have had much more experience of explosions than most of us. Moreover, their statements were given to superior officers as part of their professional duties, and the circumstances in which the statements were collected make this eyewitness evidence, in my view, very strong.
The reporters also occupy an important position in the list because their accounts in most cases are directly captured on videotape (they have not been filtered by the minds of others) and because their accounts are in most cases given spontaneously, with little reflection, very soon--minutes or even seconds--after the event they witnessed. This allows us to check for possible distorting tendencies in human recollection. (My conclusion is that the distorting tendencies in recollection have worked against the explosion hypothesis, for the simple reason that people progressively adjusted their stories as time went on to better accord with what they were being told by authority figures.) 
Before I show my next graph, let me explain how I arrived at my list of explosion witnesses. Eyewitnesses are included in my list if they use, in their statement, one of the following terms: “explosion” (or the corresponding verbal forms of “to explode”), “blast,” “blow up” (or “blow out”), “bomb” (or “secondary device”) and “implosion.” I have added a category called “other CD,” which includes cases that do not involve one of these terms but that are in some respects strongly suggestive of controlled demolition. The point of this method is not merely to be able to quantify explosion reports but to reduce my own role in the interpretive process. Eyewitnesses are included in the list not because I interpret what they witnessed as explosions but because they interpret what they witnessed as explosions.
But could people not be wrong in their interpretation? Certainly, but there are processes available that can help us check the quality of our evidence. We can carry out close scrutiny of our witnesses (names, occupations, reliability, experience); motives for deception; quality of sources; chain of custody for all witness accounts; and, of course, corroboration through other evidence of both similar and dissimilar kinds. Corroboration is so massive in the present case that the other processes have received less attention.
Here is how the list of 156 eyewitnesses breaks down:
Witnesses by term used
The “explosion” category is by far the largest, with 112 eyewitnesses. But the “bomb” category, with 32 eyewitnesses, is extremely important as well. Most of the people on this list speaking of bombs are firefighters, and it is clear from their use of the word “bomb” that they are not talking about the sort of explosion they expect to encounter in a high rise fire.
We are obviously dealing with a great many eyewitnesses, and my list is far from complete since I have not had time to incorporate several lists compiled by others.
Now, there are three common objections to the demolition argument as based on eyewitness evidence. Two have been mentioned already: eyewitness evidence is “soft” and can be disregarded; and eyewitnesses may have mistakenly reported explosions when, in fact, non-explosive events (such as falling elevators) were at issue. The third objection is the only one that I currently take seriously. It is this: there are many natural forms of explosion that occur in large fires, and the mere fact that there were explosions does not mean that explosives were used. We are making an unjustified leap, claim these objectors, when we go from eyewitness statements about explosions to the controlled demolition hypothesis.
Although I am not an expert on explosions, I do not see that there need be any great mystery about the types of explosion that typically accompany fires. They are described in detail in various publications such as the National Fire Protection Association’s Guide for Fire and Explosion Investigations  As far as I can see, there are only four types of explosion that would have been expected to accompany the fires in the Twin Towers.
1. BLEVE (“boiling-liquid-expanding-vapour-explosion,” as with an exploding boiler)
2. electrical explosion
3. smoke explosion (backdraft)
4. combustion explosion (e.g., natural gas, jet fuel vapour)
There are three characteristics of our eyewitness statements that rule out all four types of explosion. That is, these four sorts of explosions may well have occurred, but they do not account for the main explosions witnesses say they perceived. Here are the three characteristics that must be explained.
(a) Identification: If the explosions encountered were the type typically encountered in fires we would expect the firefighters to recognize them as such and name them. I have found very few instances where they do so. On the contrary, they clearly feel these were different types of explosion than those they were used to encountering, as we see, for example, by the number of references to bombs.
(b) Power: Many eyewitnesses clearly thought they were watching explosions destroy the Twin Towers (“I looked up, and the building exploded…The whole top came off like a volcano”)  But none of the common four types of explosion could accomplish this. Recall that according to NIST the Twin Towers were essentially intact beneath the point where they were hit by the planes. While BLEVEs and combustion explosions sometimes destroy structures such as wood frame houses, I have seen no evidence that they could accomplish the destruction of these enormous, powerfully built steel structures, nor have I seen any evidence that the right conditions for such explosions (for example, the necessary quantities of natural gas or jet fuel) existed in the Twin Towers at the time their dramatic destruction began.
(c) Pattern: As we have seen, many eyewitnesses reported regular, rapid energetic events in sequence down the building. As far as I can tell from reading the literature, this cannot be explained by any of the four common types of explosion. This is probably why NIST has sought an explanation of these ejections that does not involve explosions. NIST has tried to ascribe these ejections to air pressure in the buildings. If the ejections are the result of explosions they can only be explosions resulting from explosives.
(3) Eyewitness evidence was ignored/suppressed by the 9/11 Commission and NIST
I have given a brief overview of the eyewitness testimony available to us. My last main point is that this evidence has been ignored or suppressed by both the 9/11 Commission and NIST.
(a) 9/11 Commission
In its 585 pages the 9/11 Commission Report contains one partial sentence referring to eyewitness reports of explosions at the time of collapse. The context is a discussion of firefighters who were on upper floors of the North Tower when the South Tower came down. The sentence fragment is as follows:
“…those firefighters not standing near windows facing south had no way of knowing that the South Tower had collapsed; many surmised that a bomb had exploded…” 
In other words, we are supposedly dealing with a particular group of firefighters--those in the North Tower when the South Tower came down--and we are dealing with a subcategory of that group, firefighters with an impeded view. This subcategory of firefighters with an impeded view mistook the collapse of the South Tower for a bomb.
And that is that. The explosion witnesses, presumably few in number, made a mistake.
But is it true that all or most of our explosion witnesses were in the upper floors of the North Tower? No, it is not. And is it true that all those reporting explosions had an impeded view of the Towers? Not at all. The truth is that witnesses were in a great variety of locations and many of them had an exceptionally clear view of the Towers.
When it comes to eyewitnesses to explosions there is something seriously wrong with the 9/11 Commission Report
And what do we find when we examine the final report on the Twin Towers by the National Institute of Standards and Technology? One of NIST’s stated objectives is to "determine why and how WTC 1 and WTC 2 collapsed following the initial impacts of the aircraft."  But in the 295 pages of this report there is not a single reference to eyewitnesses who perceived explosions in the Twin Towers.
Some may say: well, this is not surprising because NIST deals with hard evidence, not soft evidence. NIST is concerned with things like column size and temperatures reached; NIST does not deal with eyewitnesses.
This is a misconception. The truth is that NIST is proud of its attention to eyewitnesses. Very early in its investigation of the Twin Towers NIST adopted a quite sophisticated method of collecting eyewitness evidence, and the results can be seen in Chapter 7 of the NIST final report. (“Reconstruction of Human Activity”) Telephone interviews, face-to-face interviews, and focus groups were all used. 
Note, for example, the following statement:
“225 face-to-face interviews, averaging 2 hours each, gathered detailed, first-hand accounts and observations of the activities and events inside the buildings on the morning of September 11.” 
Although Chapter 7 is not about the destruction of the Towers, elsewhere NIST explicitly recognizes the relevance of eyewitness evidence to the understanding of how the buildings came down  Yet NIST somehow fails to note eyewitness references to explosions, not only among its interviewees but also in the literature. It misses, for example, all my 156 eyewitnesses, even though it had access to all of the sources I have used.
When it comes to eyewitnesses to explosions there is something seriously wrong with the National Institute of Standards and Technology.
The 9/11 Commission and the National Institute of Standards and Technology, apparently following the lead of the FBI, have violated standard principles of investigation. Whether this is evidence of incompetence or of deliberate cover-up is irrelevant to my present argument. Either way, it is obvious that the official investigations carried out to this point have been grossly inadequate that and a new and thorough investigation is essential.
1. The importance of eyewitnesses in criminal investigation is affirmed in such publications as: Charles Regini, “The Cold Case Concept,” FBI Law Enforcement Bulletin, Aug. 1997; Charles Welford and James Cronin, “Clearing up Homicide Clearance Rates,” National Institute of Justice Journal, April, 2000; and Vivian Lord, “Implementing a Cold Case Homicide Unit: A Challenging Task,” FBI Law Enforcement Bulletin, Feb. 2005. Among social scientists an attack against naïve acceptance of eyewitness evidence (and especially against a naïve view of human memory) was led some time ago by Harvard’s Elizabeth Loftus. See, for example, her Eyewitness Testimony (Cambridge, Mass.: Harvard Univ. Press, 1979). But Loftus did not claim to have made eyewitnesses unnecessary. As she said in a book co-authored with James Doyle in 1997, “Despite the inaccuracies of eyewitness testimony and the misconceptions of jurors, the legal system can neither afford to exclude eyewitness testimony legally nor ignore it. Sometimes it is the only evidence available, and it is often correct.” Eyewitness Testimony: Civil and Criminal. Lexis Law Publishing, Charlotteville, 3rd ed., p. 7.
2. NFPA 921: Guide for Fire and Explosion Investigations. NFPA publication. Massachusetts, USA., 2004. Section 21.16.
3. “Explosive Testimony: Revelations about the Twin Towers in the 9/11 Oral Histories.” January 26, 2006.
4. Graeme MacQueen, "118 Witnesses: the Firefighters’ Testimony to Explosions in the Twin Towers." Journal of 9/11 Studies, 2006, p. 47.
5. See note 4.
6. Appendix, under “Reporters.”
7. A lengthy and important video clip showing Burkett fleeing from both collapses can be found here:
10. Appendix, under “Fire Department of New York.”
Jack Kelley eventually had to resign from USA Today in disgrace.
13. The clip from the Naudet film can be found on the internet here:
14. The Lemos interview can be found here:
15. Appendix, under “Fire Department of New York.”
16. Appendix, under “Fire Department of New York.”
17. Appendix, under “Fire Department of New York.”
18. Appendix under “Miscellaneous.”
19. Appendix under “Reporters.” Note that Bussey has been given a structural failure hypothesis within which, in the full article, he situates his experience, apparently not realizing that his description of what he actually saw is incompatible with that hypothesis.
20. Appendix, under “Fire Department of New York.”
21. A well known video clip, shown on network television on 9/11 and variously magnified and analyzed, can be found here:
22. See Kevin Ryan, “High Velocity Bursts of Debris from Point-like Sources in the WTC Towers,” Journal of 9/11 Studies, vol. 13, July 2007. Ryan discusses the NIST hypothesis and its failings. [PDF]
23. Taylor & Francis. Boca Raton, 2006. This book is part of the series, Practical Aspects of Criminal and Forensic Investigation.
24. Susan Hagen and Mary Caroub, Women at Ground Zero: Stories of Courage and Compassion. Alpha, 2002.
25. The reports submitted by PAPD officers were released along with other materials in August, 2003 after The New York Times sued the city of New York to make them public. See Kevin Flynn and Jim Dwyer, “The Port Authority Files: Voices; Officers’ Sept. 11 Accounts: Catastrophe in the Details.” New York Times, August 30, 2003. The PAPD reports in their entirety were posted in 2003 by The Memory Hole and, although this site was hacked in 2009, the documents can still be found here:
26. This is what we expect. The tendency of people to adjust their memories in this way has been noted by social scientists researching eyewitness recollection. See Loftus and Doyle (details in note 1), p. 54: “The ‘contamination’ of recollection can occur through witnesses talking to other witnesses, through questions asked by authorities, by media accounts.” And in the same volume (p. 98): “it has been shown that highly credible people can manipulate others more readily. They can persuade others, they can change attitudes, and they can influence the behavior or others in countless ways.”
27. NFPA 921: Guide for Fire and Explosion Investigations. See note 2.
28. Appendix, under “Fire Department of New York.”
29. The 9/11 Commission Report: Final Report of the National Commission on Terrorist Attacks Upon the United States (New York: W. W. Norton, 2004), p. 306.
30. NIST NCSTAR 1: Final Report on the Collapse of the World Trade Center Towers. National Institute of Standards and Technology. Sept. 2005, p. xxix.
31. NIST final report on the Towers, Chapter 7, p. 155 ff.
32. NIST final report on the Towers, p. 157.
33. NIST final report on the Towers, pp. xxxvii and 143.