9/11 third tower mystery 'solved'

[belfastuniguy 18]

9/11 third tower mystery 'solved'

By Mike Rudin BBC, Conspiracy Files

One of the twin towers collapses

The final mystery of 9/11 will soon be solved, according to US experts investigating the collapse of the third tower at the World Trade Centre.

The 47-storey third tower, known as Tower Seven, collapsed seven hours after the twin towers.

Investigators are expected to say ordinary fires on several different floors caused the collapse.

Conspiracy theorists have argued that the third tower was brought down in a controlled demolition.

Unlike the twin towers, Tower Seven was not hit by a plane.

The National Institute of Standards and Technology, based near Washington DC, is expected to conclude in its long-awaited report this month that ordinary fires caused the building to collapse.

That would make it the first and only steel skyscraper in the world to collapse because of fire.

See World Trade Center 7's location and structure

The National Institute of Standards and Technology's lead investigator, Dr Shyam Sunder, spoke to BBC Two's "The Conspiracy Files":

"Our working hypothesis now actually suggests that it was normal building fires that were growing and spreading throughout the multiple floors that may have caused the ultimate collapse of the buildings."

'Smoking gun'

However, a group of architects, engineers and scientists say the official explanation that fires caused the collapse is impossible. Architects and Engineers for 9/11 Truth argue there must have been a controlled demolition.

FIND OUT MORE... The Conspiracy Files: 9/11 - The Third Tower is on BBC Two on Sunday 6 July at 2100 BST Visit The Conspiracy FilesiPlayer website or catch up using the Q&A: The collapse of Tower 7 Timeline: WTC 7 The BBC and the 'missing' tape

The founder of the group, Richard Gage, says the collapse of the third tower is an obvious example of a controlled demolition using explosives.

"Building Seven is the smoking gun of 9/11… A sixth grader can look at this building falling at virtually freefall speed, symmetrically and smoothly, and see that it is not a natural process.

"Buildings that fall in natural processes fall to the path of least resistance", says Gage, "they don't go straight down through themselves."

Conspiracy theories

There are a number of facts that have encouraged conspiracy theories about Tower Seven.

• Although its collapse potentially made architectural history, all of the thousands of tonnes of steel from the skyscraper were taken away to be melted down.
• The third tower was occupied by the Secret Service, the CIA, the Department of Defence and the Office of Emergency Management, which would co-ordinate any response to a disaster or a terrorist attack.
• The destruction of the third tower was never mentioned in the 9/11 Commission Report. The first official inquiry into Tower Seven by the Federal Emergency Management Agency was unable to be definitive about what caused its collapse.
• In May 2002 FEMA concluded that the building collapsed because intense fires had burned for hours, fed by thousands of gallons of diesel stored in the building. But it said this had "only a low probability of occurrence" and more work was needed.

But now nearly seven years after 9/11 the definitive official explanation of what happened to Tower Seven is finally about to be published in America.

The National Institute of Standards and Technology has spent more than two years investigating Tower Seven but lead investigator Dr Shyam Sunder rejects criticism that it has been slow.

The collapse of Tower 7

"We've been at this for a little over two years and doing a two or two and a half year investigation is not at all unusual. That's the same kind of time frame that takes place when we do aeroplane crash investigations, it takes a few years."

With no steel from Tower 7 to study, investigators have instead made four extremely complex computer models worked out to the finest detail. They're confident their approach can now provide the answers. Dr Sunder says the investigation is moving as fast as possible.

"It's a very complex problem. It requires a level of fidelity in the modelling and rigour in the analysis that has never been done before."

Other skyscrapers haven't fully collapsed before because of fire. But NIST argues that what happened on 9/11 was unique.

Steel structure weakened

It says Tower Seven had an unusual design, built over an electricity substation and a subway; there were many fires that burnt for hours; and crucially, fire fighters could not fight the fires in Tower 7, because they didn't have enough water and focused on saving lives.

Investigators have focused on the east side where the long floor spans were under most stress.

They think fires burnt long enough to weaken and break many of the connections that held the steel structure together.

Most susceptible were the thinner floor beams which required less fireproofing, and the connections between the beams and the columns. As they heated up the connections failed and the beams sagged and failed, investigators say.

The collapse of the first of the Twin Towers does not seem to have caused any serious damage to Tower Seven, but the second collapse of the 1,368ft (417m) North Tower threw debris at Tower Seven, just 350ft (106m) away.

Tower Seven came down at 5.21pm. Until now most of the photographs have been of the three sides of the building that did not show much obvious physical damage. Now new photos of the south side of the building, which crucially faced the North Tower, show that whole side damaged and engulfed in smoke.

quote>

[hym 358]

I doubt it will end the conspiracy theories. People still believe that the towers where brought down by controlled demolitions nevermind there is footage of planes impacting one of the towers. (I saw it happen on live television, but that's a different issue.)

[Amerikaner 42]

Well you can see in the picture where the conspiracy comes from. In the Top photo look about half-way down and do you see that puff coming from the tower where the texture looks different? Many conspiracy's think that this is one of the many charges set in the building, although personally I don't believe in any of that either.

[Ntq€310 1]

the bigger question if it is a controled demolition, how could no one have noticed, and after the colapse of both twin towers why would the goverment blow up tower 7?

-i believe the goverment didn't do a thing-

[SimHoTToDDy 2,938]

I'm curious about these "new photos". That could make things far more plain and simple for everyone, visual evidence is what half of the conspiracies came from anyway. Just curious, but are these released to the public or still part of the investigation. I'm hoeing it wasn't just your post cut off =P.

[BurroDiablo 222]

I'd be worried about the rest of the world's Skyscrapers then if a few fires can bring down a building like that...  in fact, if it was down to shoddy design i'm surpirsed nobody is sueing the architect. Emery Roth & Sons who designed WTC7, have also designed no less than 110 skyscrapers in New York... if they made one that can be brought down by fire alone, then i'm sure theres a few more in that pile... its an arsonists wet-dream out there

[Zelgadis 638]

I've never had much patience with 9/11 conspiracy theorists.

But WTC 7 is a case for pause. I wouldn't be at all surprised if it was brought down by demolition. But at least, as far as we know, nobody was hurt when 7 came down. Then again, I wouldn't be surprised if fire brought it down either. It would be the only steel structure ever brought down by fire. But remember, it is also probably the first steel structure ever that caught fire and almost no effort was made to fight it. We don't know what would happen in that case either.

But the other towers? Well, people are just making that up.

1) The fires couldn't have burned hot enough to melt steel. True, but that didn't have to happen. The steel just needed to be weakened. The Titanic was sunk primarily due to damage sustained on steel weakened by temperature. The salt water in which it was cruising was an estimated -2C, which caused the steel to become brittle and made it more likely to crack. Weakened steel in WTC 1 and 2 is easily believable.

2) No way were those buildings brought down by controlled demolition. The bottoms of WTC 1 and 2 were mostly stable while the tops were coming down. The multitude of videos clearly show that.

3) No missile hit those towers. Unless somebody started designing missiles that are plane-shaped...

Oh, these go on forever. I just find it interesting how so many people desire to find conspiracies where none obviously exist. The odd case of WTC 7 brings questions to my mind, but I worry more that it will just fuel more crackpot theories about the other two than anything else.

ISF

[patriots_1228 51]

meh, could be worse conspiracy theories, like that disgusting "jews tried to start armegeaddon by causing 9/11" theory on youtube :S

[simzebu 19]

Even if it had been controlled demolition, why the assumption that it would have been the government? For some reason, conspiracy theorists love to come up with nearly plausible theories as far as execution, and then claim it was the government, ruining their (the theorists') credibility.

Frankly, I think it's pretty obvious that it was terrorists that did it, not the government. I don't have nearly enough knowledge of physics and architecture to know exactly how it happened, but having seen the planes fly into the towers on live TV, I'm inclined to believe that was the cause.

As for tower 7, most buildings with raging fires that nobody even tries to stop will collapse. And I think the reason it's the first is that other fires are fought.

[Duke87 1,070]

Originally posted by: zelgadis

The fires couldn't have burned hot enough to melt steel. True, but that didn't have to happen. The steel just needed to be weakened. The Titanic was sunk primarily due to damage sustained on steel weakened by temperature. The salt water in which it was cruising was an estimated -2C, which caused the steel to become brittle and made it more likely to crack. Weakened steel in WTC 1 and 2 is easily believable.quote>

One thing that primarily fuels these erroneous conclusions on the part of conspiracy theoristis is a lack of scientific understanding. I'm sure a lot of people thing that metal is solid metal and then upon reaching it's melting point spontaneously liquefies. It doesn't work that way. Metal gets progressively softer as it heats up. The Charpy impact test rather effectively demonstrates this.

For the non-civil engineers out there, a Charpy impact test is performed by putting a small sample of material in a machine looks like this:

The sample goes in it like so:

And that pendulum swings down and hits it. It's dangerous. It'll take your head off if you stick it in there.

Anyways, you can notice quite a difference depending on temperature. This is what that thing did to a piece of steel that was just in an oven beforehand:

Bent like wax. And the pendulum swung pretty high up the other side.

But when a piece of steel that was just in an ice bath was put in, it didn't bend like that. It snapped clean in two. And the pendulum was almost stopped, so the impact absorbed a lot more energy.

Point being, no, an ordinary fire can't melt steel, but it can soften it to the point where it can no longer carry the load put on it and it buckes.

This is why steel members in buildings have fireproofing material put on them. In the two towers, the impact of the planes blew that fireproofing off leaving the bare steel exposed and vulnerable.

Building 7 wasn't hit by a plane, but it was hit by a lot of falling debris from Tower 1, which would also have done a fair amount of damage to the fireproofing. Not as much as a plane impact, but bear in mind that the two towers took 102 minutes (Tower 1) and 57 minutes (Tower 2) to collapse after being hit. Building 7 didn't collapse until just shy of 7 hours after Tower 1 collapsed. Took a lot more time for the fire to take its toll. And remember, the key here is nobody was fighting that fire since the focus as on trying to rescue people from the rubble of the main two towers. And due to the extent of the fire (it was burning separately on several floors, some 30-40 stories in the air), fighting it wouldn't have been practical. Simply put, it was a pretty big fire. So, to address El Burro's comment:

I'd be worried about the rest of the world's Skyscrapers then if a few fires can bring down a building like that...  in fact, if it was down to shoddy design i'm surpirsed nobody is sueing the architect. Emery Roth & Sons who designed WTC7, have also designed no less than 110 skyscrapers in New York... if they made one that can be brought down by fire alone, then i'm sure theres a few more in that pile... its an arsonists wet-dream out therequote>

No, no arsonist could manage to do such a thing. Remember, there's a big difference in scale between several fires started by falling flaming debris and going unbattled and a single small blaze that firefighters will be attending to as fast as possible. It's not an issue of shoddy construction or design at all, it's an issue of extreme circumstances which the design didn't take into consideration.

Besides, if the design was the problem, suing the architect would get you nowhere. They're not responsible. Architects are just glorified artists. It's the engineers that do the actual designing that allows the building to stand up. So you'd want to sue the engineering firm.

[Zelgadis 638]

Originally posted by: Duke87

But when a piece of steel that was just in an ice bath was put in, it didn't bend like that. It snapped clean in two. And the pendulum was almost stopped, so the impact absorbed a lot more energy.

quote>

Yup, which is precisely what happened to the Titanic.  It definitely wouldn't have sustained the damage it did and it possibly wouldn't have sunk had it not been traveling through freezing water.

Factor that in with the cheap steel and bad rivets made of iron (!) that were used in turn of the century shipbuilding and you have yourself a disaster.

The firefighters on 9/11 were heroic to be sure, but they were doomed from the start.  Even if the fireproofing hadn't been blasted off, I doubt it would have been effective for as long as it would have taken to put out the fires.

ISF

[BurroDiablo 222]

Reasonable explaination Duke. As i've said before, i'm on the fence when it comes to the 9/11 whodunnit... I always will be untill I find a solid, undisputable arguement. However.. as i've come to relise, the Internet is full of bias... theres no 'middle ground' web site which is dissapointing. Unless there is and i've missed it...

Found this though and thought it was interesting -

The collapse of World Trade Center Building 7 features prominently in research and debate concerning the possibility of 9/11 being an inside job. This 47-storey building, located approximately 350 feet north and east a little of World Trade Center Building 1, imploded smoothly and completely into a neat pile in 6 to 7 seconds, which is the same time an object in free fall would take to reach the ground if dropped from the top of the building. This implies that WTC7 collapsed with no or negligible resistance from the support members and assembly connections of the structure, something that has never before been observed in a steel-framed building outside of controlled demolition.quote>

[raja_indy14 8]

which is the same time an object in free fall would take to reach the ground if dropped from the top of the building. quote>

i was wondering where you got this, because similar claims were made of Towers 1 and 2, when i read somewhere that they in fact fell at about 40%-50% slower than freefall.

personally, when people have brought up the 'fire wasn't hot enough to melt steel' argument i sometimes wonder at the stupidity of the human race - clearly buildings only collapse when the structural elements actually liquefy!  the claim that they're extraordinary because they're the only towers to have collapsed from fire conveniently ignores the tremendous amount of impact trauma they collectively recieved *sigh*

my father - who's an architect - has told me that in many instances wood can withstand fire far better than untreated/covered steel; it takes some time for fire to eat through a large mass of wood, so the structure remains sound (even if wooden walls etc are being rapidly eaten through) whereas a steel structure will weaken and deform leading to collapse relatively quickly.  steel is not some kind of wunder-material, and can be very prone to sagging if heated.

Top photo look about half-way down and do you see that puff coming from the tower where the texture looks different?quote>

many people say that the 'explosions' of material out of the building from floors underneath the point of collapse are the characteristic 'squibs' that are the result of controlled demolition; however, when one considers the volume of air inside the building and the speed with which it must've been expelled - carrying with it all sorts of internal debris - i fail to see why they are apparently so anomalous.

Remember, there's a big difference in scale between several fires started by falling flaming debris and going unbattledquote>

not to mention that the south face of the building recieved a tremendous amount of trauma from the collapse of the north tower a mere 350ft away, the structure of the tower was also vulnerable because it was supported on a fairly small number of internal columns, some of which were severed as a result of debris impacts - the remaining structure was then further weakened by the fires which burned out of control for hours.

part of the problem is that when one wants to believe in a conspiracy, you end up twisting the facts around to fit what you want to believe - ignoring or altering information that doesn't fit, and latching onto minor discrepancies...

[ricb 19]

There is something else that discredits the controlled demolition theory so far as I'm concerned. In all the CDs I've seen, filmed of in person (one). The explosives aren't set off at once but in a very rapid sequence. Almost as if tracers were cutting across the building. A kind of stacatto machine gun style sequence. Yes there are puffs of smoke in this case, but how anybody can say they are sequential is beyond me.

[RJ11 0]

I don't like to post frequently, as I don't want to ruin anything. But to the conspiracy theorists, how else do they melt steel? Fire, there were gas lines throughout both and probably building 7 for the diesel for the backup generators had a power outage happened. Another thing to bring up is the fact that there could be a lot of weight in the buildings and there could already in addition be cracks in the structure, just not enough to bring it down pre-9/11

[bighaben 0]

Well, I watched a video on the conspiracy theories, and I have to say they are completely wrong on this. As mentioned before weakened metal was the cause. Key support columns were damaged which fueled the collapse, and I believe something about the structure of the building itself, on the bottom floors contributed as well. Anyways, if you look at slowed down videos of the collapse, and a while prior too the collapse. You'll notice the center of the building sags quite noticeably before finally giving way.

Either way, demolitions of any kind would have been seen, people are not mindless drones, even if they are heading to work.

[Red1530 1]

Originally posted by: Duke87One thing that primarily fuels these erroneous conclusions on the part of conspiracy theoristis is a lack of scientific understanding. I'm sure a lot of people thing that metal is solid metal and then upon reaching it's melting point spontaneously liquefies.quote>

  I think the reason people think that is because ice does that and is the only material that most people normally see go through the three phases of matter: solid, liquid, and gas.

[Patricius Maximus 236]

I think that the jet crash was the primary, if not the only, cause of the Twin Towers collapse. About the third tower, I can see both explanations. There was no conclusive, undisputable cause found to date. Fire could have weakened the steel, then again it could have been a clever demolition.

However, I lean towards the fire theory with the third tower. I believe that the Twin Tower collapse was caused by the plane crash and resulting fires. If so, then why would the CIA, FBI, or other organization go to the trouble and expense of wiring an insignificant tower to explode at the same time? That makes no sense to me.

I cannot completely discount a theory of operational cooperation between the US government and Al Qaeda. 

If so, it would have to be so secret that the theory's factuality would be highly improbable, but not impossible. No one can deny that Area 51 exists, but it took 30 years for it to come out into the public eye.

So, I'd say operational cooperation is possible, but highly improbable. As for the entire 9/11 incident being caused by the US government, I think it is almost impossible.

[Nerd_Guy 4]

I hate conspiracies...... 
I mean, it has been obvious since WTC7 collapsed that it was NOT controlled.  The fire was allowed to burn while emergency workers were focosued on the main two towers and weakened the structures.  I have heard people claim that the government was trying to cover something up by having all of WTC7's steel melted down.  Steel is very valuable these days and is recycled as soon as possible.  
I have even argued on this site with someone who thought an American cruise missle hit the Pentagon, in spite of security camera footage showing the plane crash!

[fukuda 351]

I think the reason people think that is because ice does that and is the only material that most people normally see go through the three phases of matter: solid, liquid, and gas.quote>

Indeed, it's just that the hydrogen bonds between water molecules and the metallic bonds between Fe-Fe, Fe-C atoms have completely different behaviours, a regular crystal like water, sustained by hydrogen bonds and both intermoleular forces (Van der Waals) will only behave as a liquid when the hydrogen and Van der Waals bonds are weakened enough to allow the molecules to roll over themselves, unlike steel, where there are only electronic clouds keeping alloying atoms together, you only need to heat the material to start weakening the electronic clouds and allowing the atoms to start rolling way before the melting point is reached.

[Hahayoudied 3]

No fire could ever reach high enough in temperture to melt steel, but fires can get hot enough to soften the steel, which greatly reduces the steel's ablity to hold the weight.

[thothagrammaton 0]

there is no mystery as to whether wtc tower 7 was brought down by controlled demolition ... i have videos of the owner larry silverstein admitting in a televised interview that tower 7 was "pulled" (purposely imploded) after talking to the nyc fire chief, and also proof of his words with footage of cutter charges racing up the side of the building as it is coming straight down into its own neat little footprint ... no metallurgy, speculation, or argument needed

[fukuda 351]

Oho.. so Silverstein knew previously that the twin towers were going to be hit by 2 airplanes and prepared a plan to demolish his own building using the crash as an excuse?

Or did he introduced the explosives into a severely controlled area after the 2 towers were hit by the planes?

Doesn't sound very realistic...

[Duke87 1,070]

No, see, the steel melted a lot easier because of global warming.

And all those Cubans who worked with Lee Harvey Oswald helped direct the heat at New York.

Actually, scratch that. WTC7 never actually collapsed. It was filmed in a movie studio. Neil Armstrong directed it.

[raja_indy14 8]

i have videos of the owner larry silverstein admitting in a televised interview that tower 7 was "pulled" (purposely imploded) after talking to the nyc fire chief,quote>

in the videos i've seen, this statement is always taken out of context. he was asked whether they should remove the fire teams as the building was in danger of collapse, he responded that they should be "pulled" from the building to prevent further casualties - not that the building should be collapsed.

Silverstein knew previously that the twin towers were going to be hit by 2 airplanes and prepared a plan to demolish his own building using the crash as an excuse?quote>

he was clearly in league with bush/al-qaeda and hoped to collect on the extra insurance money he could get from another building falling down!

as it is coming straight down into its own neat little footprintquote>

why should a major office building topple over? the centre of gravity is such that the structure will normally fail - due to the tremendous stresses, especially after having been subjected to fire - and collapse straight downwards rather than topple sideways. when the south tower of the world trade centre collapsed the part of the tower above the impact site was beginning to lean; the tremendous forces this applied to the compromised structure led to comprehensive failure long before it had leaned far enough for it's centre of gravity to shift to the point where it would actually fall sideways...

[thothagrammaton 0]

i understand that demolishing a building takes weeks or months of preparation, and i also understand the sarcasm that accompanies perhaps a lack of exposure to legitimate  information regarding outrageous claims; i am merely reporting what i have seen on video ... a more outrageous claim perhaps would be that there was no inside conspiracy involved when the most powerful country in the world failed to put up one military aircraft in over an hour to combat a group of men reportedly wielding boxcutters who could barely fly cessnas ...  if i am allowed to post links here on this forum i will supply the links to the videos i cited in my first post

[thothagrammaton 0]

i understand that demolishing a building takes weeks or months of preparation, and i also understand the sarcasm that accompanies perhaps a lack of exposure to legitimate  information regarding outrageous claims; i am merely reporting what i have seen on video ... a more outrageous claim perhaps would be that there was no inside conspiracy involved when the most powerful country in the world failed to put up one military aircraft in over an hour to combat a group of men reportedly wielding boxcutters who could barely fly cessnas ...  if i am allowed to post links here on this forum i will supply the links to the videos i cited in my first post

[raja_indy14 8]

oh, i'm sure i've watched most of the videos, i also know you shouldn't really believe a lot of things on the internet.

that accompanies perhaps a lack of exposure to legitimate information regarding outrageous claims;quote>

oh no, i've been exposed to at least the vast majority of the more 'legitimate' claims, i suppose i'm just negatively biased towards conspiracies or maybe i just have a basic level of common sense...

a more outrageous claim perhaps would be that there was no inside conspiracy involved when the most powerful country in the world failed to put up one military aircraft in over an hour to combat a group of men reportedly wielding boxcutters who could barely fly cessnas ... quote>

i must admit, the facts as they are do seem a little outrageous - the world superpower taken utterly by surprise?! how can that happen?! no, clearly the government was in league with the terrorists, and they used remote controlled airplanes, and relocated all the people who were on the airplanes and gave them new identities, and NORAD was told to stand down, and even though they flew remote-controlled planes into the buildings they thought they better make sure and rigged the whole thing with explosives - and all this complex operation was done secretly without anyone knowing because the CIA might just be the most impressive secret service organization the world has ever seen - or maybe it was the 'Impossible Missions Force'. now that isn't outrageous at all...

[fukuda 351]

a more outrageous claim perhaps would be that there was no inside conspiracy involved when the most powerful country in the world failed to put up one military aircraft in over an hour to combat a group of men reportedly wielding boxcutters who could barely fly cessnas ... if i am allowed to post links here on this forum i will supply the links to the videos i cited in my first postquote>

It's a very though decision to destroy a plane full of citizens, especially when you don't know beforehand the plans of the terrorrists, and yes, you can (and should) post links to your sources

raja: nah, those of the CIA are little puppets compared to the NSA, tehy must be the culprits!

[Hahayoudied 3]

Are people are starting to joke around now with their posts, or are they ignorent?