to believe some if not all of the 9/11 conspiracy theories

[mrsunreasonable]

NOTE: This is not meant to be offensive and if you suffered as a result of 9/11 you have my deepest sympathies it was a terrible event however it was caused.

Having watched a few documentaries on the conspiracy theories I am partially if not completely convinced all was not as it seemed. The fact that many witnesses that saw/heard things that didn't tie in with the official version have since died in suspicious circumstances doesn't help!

People accept what they're told? When there were phone calls from people on the hijacked planes saying, 'We've been hijacked?' Black box recordings with evidence of hijacked planes.

Thousands of people seeing planes fly into buildings.

Yes, it's all just a big fat lie!

The government was in cahoots with extremists to destroy itself because well, that's such a sensible thing to do.

Snorbs I don't buy it. Your explanation covers the destruction of the lower floors which were basically made of cardboard, or may as well have been. But the central 47 steel columns were not, and they didn't remain standing. Why not?

Please, everyone who is sniggering, tell us why. You just look like you are bluffing.

Apparently this is distasteful and inappropriate, but still it's ok to piss yourself laughing at it and make jokes about 7/7.

Ooookaay

Actually FA, the main strength that my argument has is that it's the most likely explanation if you take into account the motives and opportunity of all concerned.

The thing that conspiracy theorists fail to address is why the official version is so unlikely. It's not unlikely at all. It is entirely within the bounds of probability.

Of course governments lie but conspiracy theorists also have agendas. Most are pretty paranoid about government for a start.

Agree completely, chibi! It's beyond offensive to all those thousands of people who died, many of whose remains were never found and their families don't know if they were killed instantly or died horrified and scared.

who is pissing themselves laughing and joking about 7/7?

"...have you actually got a better step by step explanation of how a part of a building putting pressure on the remaining building would actually have the power to shear off the incredibly thick steel columns inside the core of the building, right down to the ground, into little pieces..."

When 9/11 happened I was watching the TV with a friend who happens to be an engineer. He was horrified that fire crew were racing to the building because he predicted, rightly, that the position of the fires meant the upper storeys would collapse and the combined weight coming down would result in the lower storeys impacting in on themselves.

I think the people who organised that terror mission were probably quite surprised at the net effect. However, if my friend could predict it, presumably many others did as well.... and without having to resort to daft ideas of the building being primed to explode.

Expat, how do you know it's a 'fact'?

Really, how?

Are you just more intelligent and knowledgeable than the rest of us?

Chibi I can see that sometimes it is ghoulish but at the crux of it is a government in our opinion willing to be proponents of an outrageous misinformation campaign - while having the blood of those people on their hands.

That's not ghoulish I suppose? I just don't see why your belief in the official storyline is ANY more valid in ours of the unofficial one.

Unless the government really is always honest.

B&T, yes it is possible that the official line is accurate. I just doubt it and so do a lot of other people.

Does that make us more disrespectful than those unwilling to question or look further into it? Thos happy to accept the media hype about Al Qaeda, unfettered by concern over the bits that do not add up?

Sorry, '.. more valid than ours in the unofficial one.'

I agree with FA. Governments keep hoi polloi where they want us via the use of continual misinformation and propaganda. It's how it has always been and will be. To think otherwise is simply naive and actually, dangerous.

I'm not saying that proves any conspiracy theories about 9/11.....rather that I can understand people being dubious about the motives of the Bush administration, or any government.

Just one example, had the lower floors been crushed by the impact of the upper floors, this would have stopped roughly half way down as the load above, largely dissipated around the island by then, had ceased to be a huge force - the lower half of the structure would have given a lot of resistance to the by then massively diminished load coming directly down onto it.

You're starting off with 50 floors + coming down on the lower 50 or so...by the time these have exploded off the footprint, there's not going to be much force at all. So I'd guess around 40-60 floors at the base of each tower would remain in place, damaged but upright.

equal and opposite reactions and all that.

They didn't though - all totally pulverised, as Snorbs says.

A significant number of those 47 columns were severed or at least severely damaged where the aircraft him them. The rest were severely weakened by the heat of the fire - again, in and around the floors of the impact site. When the building started to collapse the weakened core collapsed too (again, at or around the point of the initial impact).

After that, the remaining columns of the core were being hit hard from above by thousands of tons of falling concrete and steel. Although the lower levels of the core possessed an immense amount of strength (as they had to, to support the static load of the building) it wasn't enough to resist the enormous dynamic loads. As the upper floors - including the core - fell they were collecting up more floors, and more bits of the core, as they went. And they were accelerating as well. So even though the core columns below the impact point were effectively undamaged they simply weren't strong enough to stand up against the loads hitting them.

Buildings are designed to withstand static loads from gravity as well as sideways dynamic loads from wind, earthquakes etc. They're not designed to withstand vertical dynamic loads like this.

(Also, according to the building engineers I talked to, the basic WTC tower design wasn't particularly good. It was too reliant on the horizontal floor trusses and their not particularly resilient connections to the rest of the structure.)

Teaching a dog to read is a pointless endeavour.

How were they accelerating? I would have thought they would progressively slow as each pocket of resistance was met, ie each new floor structure it took out.

This explains it better than I did:

'Add to this the fact that the lower half of the 47 columns contained 4 times the mass of the upper half, because of the tapering. This means that the vast majority of the lower half would remain cool to the touch thus leaving 550 feet of columns with nearly 100% of engineered strength.

Now we all know that the towers started collapsing from the upper part of the upper half and that they were in essence disintegrating as they came down, throwing off the debris to the sides. And we know that the lower half had to support itself and the upper half so by the time it got half way down there was this massively strong lower half with just over half the mass of the building to support. Essentially, at that point, the lower half was only supporting half what it was 5 seconds before.

Theoretically it should have stopped collapsing at that point. This is the only logical result that should have happened. At a very minimum you would be left with 47 columns sticking up in the air over 500 feet after all else crashes down. What actually happened is beyond physical reality and is totally absurd.

So how do we explain the complete collapse? Actually we do not have to, it is their story that does not make sense. They have not been able to explain this without changing their official story several times yet there is still no practical nor logical explanation coming from them. Indeed there is no possible reason other than controlled demolition. '

Expat these revelations are astounding. I am none the wiser.

Expat was

The engineering details are interesting

Flightattendant, you should look up 'Fred Dibnah' late Bolton steeplejack who had an interesting technique for bringing down very large disused mill chimneys, often in confined urban spaces. He used a combination of wooden props (realtively weak structure) and a very large fire to fell the chimneys.... no dynamite whatsoever. The very same principle that applied to the Twin Towers.

I know about Fred, Chibi - great bloke

However chimneys are made from brick, not steel.

I think he would have had trouble with steel.

demonstrating the 757 crash into the Pentagon.

They were accelerating because of gravity. Each time a floor collapsed the upper levels fell another 3 metres, more-or-less unhindered. Momentum was lost at each floor collapse but it was more than made up for by the next 3m fall.

Yes, the lower levels of the core columns were thicker and stronger than the upper ones. But they hadn't been relieved of a lot of the static load. The upper floors were still there; they hadn't vanished. Sure they were being crushed and a lot of lighter debris was going sideways but most of the structure was falling downwards and that load has to go somewhere.

So the lower columns were trying to support both a significant amount of the existing static load plus the dynamic load caused by the descent. And as every additional floor was caught up in the collapse, its mass was added to the falling mass and so the dynamic load increased still further.

The momentum of thousands of tons of falling building represents a force that is orders of magnitude greater than the static load.

"Thos happy to accept the media hype about Al Qaeda"

Er, to be fair, Al Queda's portrayal of themselves is not wildly different to that of anyone else's portrayal of them. They're hardly working day and night to dispel their poor public image.

Having a different theory is fine, but the issue is that these theories are based on "information laundering"- similar to money laundering whereby "opinion" does the round of so many websites that it's untraceable and so eventually it becomes "fact".

If anyone in "officialdom" dares to dispute these "facts" the theorists say "Oh, but they would say that, because they're part of the plot."

" I would have thought they would progressively slow as each pocket of resistance was met,"

But the mass of debris increases as each floor is disrupted. As each floor of a building collapses, the dropping mass increases and the strength of the remaining building reduces. Moreover, the debris is itself accelerating under the influence of gravity.

The quote you cite is simply engineering illiteracy. It's assuming that the lower half of a building retains its strength when the top half is removed (reality: the floors are in tension pulling the walls together). It's assuming that a structure capable of supporting a static load can support the same load dropping on it from an arbitrary height (reality: the collapsing roof of a building will cut straight through the upper floors, gaining mass and energy as it falls).

"And we know that the lower half had to support itself and the upper half so by the time it got half way down there was this massively strong lower half with just over half the mass of the building to support." is utter stupidity. There's something rather pathetic about people who don't understand physics quoting nonsense from other people who don't understand physics, assuming that the audience doesn't either. If true, it would mean that no wall could ever collapse.

Sorry, Chil not Chibi.

Tokyo if you happen to know it's engineering illiteracy, then I accept your version...I said I don't have any expertise myself. All I'm doing is reading up, and questioning what we have been told.

thanks for calling me pathetic though. Had you taken up my invitation to explain how this worked far back in the thread I may not have believed the bullshit I found elsewhere in cyberspace but no, you sat abck and watched me quote some crap instead so you could laugh.

I don't think that reflects well on you, really.

Oh and if you ARE good on engineering please, PLEASE explain to me how the lower parts of the steel broke into bits.

Nobody has yet and the PM link didn't. It just lumped the steel columns in with the rest of the useless quot the floors were made of.