An interview with explosives expert Brent Blanchard
The most controversial aspects of the 9/11 attacks are the collapses of the Twin Towers and of 7 World Trade Center. For years they have been the center of conjectures by authors who are not competent on the subjects that they discuss.
Undicisettembre has already published the technical opinions of Italian explosives expert Danilo Coppe and of professor of Civil Engineering Charles Clifton; now we offer our readers a third expert opinion in this interview with American explosives expert Brent Blanchard, who provides another authoritative debunking of conspiracy theories.
Brent Blanchard is a demolition expert; he serves as Operations Manager for Protec Documentation Services, a world leader in engineering and vibration consulting for explosive demolition projects. He's also a senior writer and editor at the website Implosionworld.com.
We thank Brent Blanchard for his kindness and for his willingness to share his thoughts.
Undicisettembre: What do you think of the collapses of the Twin Towers? Were they controlled demolitions in your opinion?
So my direct answer to that question is no. There is no evidence that we have ever seen that it was a controlled demolition.
Undicisettembre: Looking at the collapses, what tells you they were not controlled demolitions?
Brent Blanchard: Well, there are a few things right away. For instance most sections of each structure fall outward. Tall sections of the North Tower legged out very far to the East and to the North, while other large sections of the building sheared away. This is totally dissimilar to a controlled demolition.
Undicisettembre: In your opinion, would it be possible to prepare such big buildings for a controlled demolition without anyone noticing?
Brent Blanchard: To prepare those buildings for being demolished would take a lot of preparation. You would need a lot of people involved or you would need a few people for a very long time: weeks minimum, months probably. And they need direct access to the columns. They would not only need access to the buildings undetected but they would need access to the H-beams. They would need to do something to pre-weaken those flanges. There's work that needs to be done or the explosives just wouldn't work.
So you would need people to go inside the building for a long time, and people in the offices would obviously notice that there's something going on. You would also need all these people working on the columns – and witnesses - to stay completely silent about this for many years afterward and not tell anyone, not even their parents or their wife. Not even on their death bed.
Brent Blanchard: There are different ways you can approach it. You could have a small crew working in different areas for a very long period of time, or if you have many people obviously they would need less time. But again anyone who works in the building, even maintenance people, could see areas where walls were broken away to access the beams. You have to access the beams, you cannot just put explosives in a room and set them off and expect anything to happen to the beams. The explosives would follow the path of least resistance, they would blow up a bunch of windows and nothing would happen to the beams.
Undicisettembre: In case you actually wanted to demolish the Twin Towers with a controlled demolition, would you have used a wire to start the explosions or a radio signal?
Brent Blanchard: If I wanted to have the least amount of detection and of physical evidence I would have used a radio wireless frequency detonator, but there's still no way to wire all those columns together without using any wire. Even with a wireless detonator you would still have to tie these columns together. And the biggest point is still that you need access to those columns. There are only two ways you can blast such a thick steel H-beam. One is to bulk load it, which means you take a big load of explosives and you just duct tape it or attach it to the beams and you just let it rip and obliterate the beam. The second way, which is what happens with true controlled demolitions, is that you cut through the flanges and you attached the charges to a point where the flanges are pre-cut and then you finish the job with the explosives.
Those are really the only two ways to cause a beam of that size to fail. Now you have to magnify that times dozens, if not hundreds, of beams. Because if you shoot ten of those nothing is going to happen, the building won't fail. You have to shoot many more than that, because the weight is distributed around that structure at the core and around the perimeter. Both methods would be extremely noticeable to the naked eye.
Furthermore, if you were going to bulk load the columns, you would have not only seen the fireball where the plane hit but also huge fireballs everywhere these explosives detonate, and nothing of the sort was seen.
Undicisettembre: So in case of bulk loading there would have been fireballs also at lower floors. Everywhere in the building.
Brent Blanchard: Absolutely. Wherever you set those explosives you have to have a sharp release of energy and a release of gasses. There would be a combustible event, you can't help but notice it. It displaces air, it displaces material, it would be extremely noticeable.
Brent Blanchard: Well, folks tend to say, “We saw a lot of puffs of smoke coming out down the building and then the building collapsed”. What we say to them is that if you look more closely what you see is that the building begins to collapse first and then you see those air puffs. It's a very subtle difference but if you are looking for it you can absolutely see this difference. If you had seen air puffs first it could have been a catalyst for the building to collapse, but when you see them secondary that means that air is being compressed down, because the collapse mechanism has started, and as this air is compressed it has to escape out of those windows and out of those sides of the building. There's no other way for it to go.
Undicisettembre: If you actually had to demolish buildings like the Twin Towers, what kind of explosives would you use?
Brent Blanchard: You’d have to use something that causes the steel to fail: linear shaped charges, RDX materials, C4, very powerful high-velocity stuff.
I have heard thermite mentioned. That's not practical at all. Again you need a very, very high velocity, very strong military-grade explosive material.
Undicisettembre: Since you already mentioned thermite, let's proceed with this topic. What do you think of thermite? Is it even vaguely possible to demolish the Twin Towers and 7 World Trade Center with thermite?
Brent Blanchard: No. In explosive demolitions thermite is never used.
The thermite assertion first came out three or four years after the event; there was no talk of thermite until 2004 or 2005. All of a sudden this new theory came out because all other theories were very easily proved impractical or impossible.
There was a professor over here in States that decided back then that thermite was his new theory, but the more you look into thermite the more you understand that the way it causes the metal to fail is not consistent with what happened. Then he changed his theory into nano-thermite and now he might even come out with double-nano-thermite. There are always variations that pop up about how thermite might have been used.
In order for thermite to work you have to have a release of the chemical and the chemical has to actually cause the steel to deteriorate. I don't how they think it can be done to an H-beam, or to any very thick steel beam. Thermite doesn't work horizontally, it works vertically. You can't cause thermite to cut horizontally through steel. You can't attach thermite to a bunch of columns, dozens and dozens of columns, and expect it to start cutting clean through all those columns at a predetermined time or especially finish at the same time. I don't understand how it can even theoretically occur. And it's never been articulately explained by the theorists.
Thermite folks just tend to assert that a bunch of guys went in there, put thermite on columns that happened to already be exposed, them somehow triggered it all, and the thermite somehow cut horizontally through a bunch of columns at the same time and caused the building to fail. That makes no sense whatsoever.
Thermite also burns very hot but very slow and it's uncontrolled. When you see tests for thermite you often see it burning on a steel plate, it creates a lot of fire and reaction, but none of these reactions were seen in the Twin Towers. And again, it doesn't burn horizontally through columns that are load bearers. I don't know how it can happen.
Brent Blanchard: Well, some mechanism has to be able to attach the thermite to all those columns, but the thermite must not cut through that attachment mechanism itself, and it has to be triggered later on, in sequence, on a lot of different columns, and have the same burn rate through all the columns for the structure to come down.
It doesn't make any sense. The thermite argument doesn't make sense to the point of being a discussion worth having.
Undicisettembre: A question I heard recently is: if thermite had been used, would it have produced a lot of light that would have been clearly visible from outside?
Brent Blanchard: It would have created a whole lot of light. It would have created a lot of fire, a lot of flame, of glow, smoke, all prior to the collapse. It didn’t, because there was no thermite.
Undicisettembre: What do you think about World Trade Center 7? Was its collapse a controlled demolition, in your opinion?
It's not surprising to me that that building collapsed. I wasn't aware at that time of the gasoline storage or the damage to the south side of the building, but even without that knowledge you could see fires burning freely for hours. And if you let a fire burn freely in any structure, sooner or later that structure is going to collapse.
To me, the fact that it collapsed so many hours after the other towers tends to support evidence of the natural progression of the collapse rather than some sinister plot.
Undicisettembre: Conspiracy theorists also say that the collapses were too fast to be natural. Is it possible, in your opinion, to distinguish a natural collapse from a controlled demolition based on the time the buildings take to completely come down?
Brent Blanchard: No. It's really impossible to gage exactly how long a building should take to come down in this situation. First of all, there are no other failed buildings of that size to compare them to. Secondly, you don't know exactly what type of resistance was inside those buildings as they started to collapse. Each floor truss created some resistance, but so did the furniture, and elevator shafts, and everything else in there. Folks can guess, but nobody knows exactly.
The key of the entire discussion of whether this was a controlled demolition is to establish where the collapses start in both buildings. Anyone who looks at the videos must reach the inescapable conclusion that the collapses both start right where the plane struck. They don't start collapsing at the structure’s bottom or in the middle or someplace else. The building begins to fail right where the plane hit.
If you accept that as a basic fact, then you need to reach the conclusion that if there was some controlled demolition involved it would have to occur on those same floors. So theorists must also make the allegation that people somehow got access to those same floors, either before or after the planes hit, but accessed those exact points of contact and added more explosives there to start the building collapsing. And the question is: why would anyone do that? And the biggest question is how can anyone possibly go into those areas with such high temperatures and start to attach explosives? And if the explosives were attached there beforehand, how did the impact of the planes not blow those explosives clear off the columns and out of the buildings?
Those are key questions that no theorist seems to be able to answer.
Undicisettembre: Also, to assert that these collapses are suspicious they should start by asserting that controlled demolitions make the building fall faster that natural collapses. In your opinion, is that the case? Do controlled demolitions make the building fall faster than a natural collapse?
Brent Blanchard: Well, a building will fall only as fast as resistance will allow it to fall. When a blaster makes a building collapse he's not putting explosives on all columns but only a certain number of columns to cause the building to start to fail. Even at the World Trade Center when enough columns failed - because of the high temperature of the steel - it started the collapse mechanism. This is not dissimilar to what a blaster does on a controlled demolition: they use the least amount of explosives on the least amount of columns to get the desired effect. The blaster doesn't care how fast it falls, he just cares about making it completely fall.
So there's really no way to predict an exact collapse rate for a structure.
Undicisettembre: So do you think the time it took the Towers to collapse on 9/11 indicates anything mysterious?
Brent Blanchard: No, I see nothing mysterious about it. I see them collapsing exactly at the rate they would if they were to fail at the points that they did where the plane struck. They met a certain amount of resistance while coming down, and some other areas that did not resist peeled outward, and those elements legged into other buildings. That is a very important distinction when you try to explain why this didn't look like a building implosion.
Undicisettembre: Many conspiracy theorists believe that molten steel was found at the bottom of the towers and this should prove it was a controlled demolition. Is it true that controlled demolitions leave molten steel pools?
Brent Blanchard: No. And there is no evidence there was molten steel. The way they phrase that question is fundamentally wrong and that's why it reaches wrong conclusions every time. There were molten materials, there were very hot burning materials, but there's no evidence that any of those materials were steel. It is much more likely that they were aluminum, or copper, or composite materials.
Undicisettembre: Talking about the three collapses that occurred on 9/11, are conspiracy theories that claim they were controlled demolitions even vaguely reliable?
It's unfortunate and it's dangerous because it prevents constructive conversation about 9/11, and it makes the Western World look very bad in front of a bunch of fanatical people who believe this stuff if it's thrown out there too much. None of this can do any good to civilized people, it can only do bad. This misinformation can only create worse dialogue, worse animosity between people. Which is one of the reasons why we decided to speak up against it. It would be a lot easier for us to say “We have no comment”, and a lot of people do say that. We don't say that because we work around the world and we get these questions everywhere we go, often over a few beers after a day or two of being there. It shows that conspiracy theories can run far and that this one is running to a lot of places and can do a lot of harm to innocent people. I don't think it's very productive, rather it puts everyone in needless danger.
In 2006 we released a report addressing these theories and I, together with a couple of assistants, spent a lot of time contacting all demolition contractors that were on the site. Some of them looked at us like we had three heads, they couldn't believe we were even raising the subject. They asked, “What's the point of you asking to me about this?” This concept is so foreign to them that they can't believe there's someone out there who would take these assertions seriously. What they truly think is, “Why are you wasting your time on this?”
Undicisettembre: Is there anything else I did not ask you that you want to add?
Brent Blanchard: One thing I would add is that there are vibration recordings from the site. The seismograph readings that were recorded on 9/11, as they are every day worldwide, recorded the impacts of the planes and the actual collapses of the structures. You can see in those waveforms and in that data that there was no sudden catalyst at 10:06 or any other time; there was no explosive event. So in order for an explosive detonation to be hidden, folks at those laboratories, actual scientists at Columbia University and other places, would also have needed to be part of the conspiracy.
In the end there is absolutely no scientific evidence that there were explosions in any of those three buildings, and that means a lot to me.