South Tower Top Section Lean

Hi all.

I've been listening to a few audio debates, a couple involving Richard Gage, and this one topic constantly comes up.

The claim by conspiracy theorists is that the top of the South tower leans over, and then seemingly out of nowhere, just begins to fall down through the building instead of falling off the top like "it should".

The usual rebuttal consists of everything from force of gravity, lack of angular momentum, lack of solid pivot point for the top section to continue pivoting on, dealignment of core columns from the tilt, etc.

I've been looking at videos of the South Tower from multiple angles, and have made several observations.

1. The top section does not begin leaning over first. The top section begins a downwards motion at the same time, if not slightly before the top section begins leaning to the east.

2. The lean and angular momentum of this top section does not suddenly stop in favor of a downwards motion. It appears to continue as the collapse accelerates downwards.

3. The east face of the top section does in fact end up falling off the side of the building.

4. The remaining top section, including the additional mass gained per floor as the building collapses, continues to cause the collapse of the south tower.

Conclusion:

Conspiracy theorists have been wrong on two counts; that the top section began leaning before any downwards motion, and also that the top section, or at least the east face of that top section, did actually end up 'tipping' off.

Although this does not really change anything, I figured it was worthy of mention, being as it seems to be consistently bought up in conspiracy arguments.

Have a watch of some of these angles, you'll see what I mean. In particular, have a look at what happens to the top section on the East side of the building as it collapses.

[edit] In particular, the small clip at 1:27, 1:35, 3:50, 4:56 (probably the best one), 5:48 (notice the East face of the top section) Just to point out a few.

cjnewson88 said:

1. The top section does not begin leaning over first. The top section begins a downwards motion at the same time, if not slightly before the top section begins leaning to the east.

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No. Progression of perimeter failure can be observed traversing from East to West on the North face of the building...

2. The lean and angular momentum of this top section does not suddenly stop in favor of a downwards motion. It appears to continue as the collapse accelerates downwards.

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Correct, though it does reduce.

3. The east face of the top section does in fact end up falling off the side of the building.

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No. That is the LOWER East face being pushed outwards by the descending tilting upper section...

femr2 said:

cjnewson88 said:

1. The top section does not begin leaning over first. The top section begins a downwards motion at the same time, if not slightly before the top section begins leaning to the east.

Click to expand...

No. Progression of perimeter failure can be observed traversing from East to West on the North face of the building...

Click to expand...

It seems to me that this question is a great deal deeper than whether the top block rotated before or after beginning to descend; the problem is defining what part of the motion is considered rotation and what part descent. If you want to deconvolute the motion of the upper block into rotation and translation, then it depends where you place the axis of rotation. Place it about the hinge point and there can be no downward motion until the hinge fractures, which will inevitably be at a non-zero rotation. Place it nearer the building centre and you'll find a downward motion term as soon as you take out the rotation. Place it higher up and out pops a lateral motion term. Most conspiracy theorists, though, don't have a good enough grasp of geometry to even understand that there's an issue here. Their claim isn't even wrong; it isn't being coherently stated.

Dave

Dave Rogers said:

It seems to me that this question is a great deal deeper than whether the top block rotated before or after beginning to descend; the problem is defining what part of the motion is considered rotation and what part descent.

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It's been discussed in detail at the911forum.

The exact pivot point is still a bone of contention, but West side of core is probable.

The East to West progression of perimeter failure can be seen.

There's not vertical descent of the entire upper section before rotation begins.

There's a clear "release point" of the upper section, when the West face fractures.

The scenario suggested by cjnewson88 did not happen.

Am sure I have some trace data for WTC2 initiation kicking about.

ETA: And lest it's forgotten...it won't be a rigid structure either.

femr2 said:

It's been discussed in detail at the911forum.

The exact pivot point is still a bone of contention, but West side of core is probable.

The East to West progression of perimeter failure can be seen.

There's not vertical descent of the entire upper section before rotation begins.

Click to expand...

Again, definitions. If the upper block is pivoting about the West side of the core, then the East side of the block is descending from the moment rotation begins, simply because of the rotation. Simple geometry. It's a geometrical impossibility for the top section to rotate without at least some part of it moving downwards. So any statement of the form "the top of the tower starts leaning before it starts to fall" is so vaguely framed as to be meaningless; the very fact that part of the tower is leaning means that it has begun to fall.

Dave

Dave Rogers said:

Again, definitions.

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Not really necessary.

You know as well as I do that "rotation/tipping" preceeded "release/vertical descent" of the upper section.

If the upper block is pivoting about the West side of the core, then the East side of the block is descending from the moment rotation begins, simply because of the rotation. Simple geometry.

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Sure, and again I suggest reminding yourself that it's not a rigid block either.

Slightly pedantic geometry of rotation about pivot discussion aside...

The OP suggesting vertical descent before rotation is incorrect. Clear tipping occurred before release. A point I note you chopped from my previous response.

It's a geometrical impossibility for the top section to rotate without at least some part of it moving downwards.

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...and some other part moving upwards, given the suggested pivot point, assuming a rigid block, ...

So any statement of the form "the top of the tower starts leaning before it starts to fall" is so vaguely framed as to be meaningless; the very fact that part of the tower is leaning means that it has begun to fall.

Click to expand...

You decided to cut out the real=world clarification...

There's a clear "release point" of the upper section, when the West face fractures.

The scenario suggested by cjnewson88 did not happen.

Am sure I have some trace data for WTC2 initiation kicking about.

And lest it's forgotten...it won't be a rigid structure either.

Sorry, I forgot who I was talking to. Let me try again:

Yes, femr2, you're right. It doesn't matter what I said, or whether you've got the faintest understanding of what I meant, or what anybody else said; you're just right, because you always are.

Happy now?

Dave

femr2 said:

...and some other part moving upwards, given the suggested pivot point, assuming a rigid block, ...

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This is not necessarily true. A block that is hinged at the corner will not have any part of itself moving up at any point. Of course, that is a mathematical idealization and hardly in any way realistic, but you're just trying to avoid the point: Downward motion and rotation are inextricably linked and difficult to differentiate.

Dave Rogers said:

definitions. If the upper block is pivoting about the West side of the core, then the East side of the block is descending from the moment rotation begins, simply because of the rotation. Simple geometry. It's a geometrical impossibility for the top section to rotate without at least some part of it moving downwards.
Dave

Click to expand...

This was what I was getting at. However I was also looking at the idea of whether there was any downwards motion before the tip began. I don't give the western pivot as much credit as others seem to.

femr2 said:

No. Progression of perimeter failure can be observed traversing from East to West on the North face of the building...
[qimg]http://femr2.ucoz.com/_ph/5/2/152523643.gif[/qimg]

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See Daves post.

No. That is the LOWER East face being pushed outwards by the descending tilting upper section...
[qimg]http://femr2.ucoz.com/lateperimeterpeel.gif[/qimg] [qimg]http://femr2.ucoz.com/hhj0000.gif[/qimg] [qimg]http://femr2.ucoz.com/_ph/5/2/728291055.gif[/qimg]
[qimg]http://femr2.ucoz.com/lateperimeterpeel2.gif[/qimg] [qimg]http://femr2.ucoz.com/tilttt.gif[/qimg]

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I would disagree. Look at your own .gif better, the lower easter face is being smashed to piece well before that eastern face collapse becomes visible. To my observation, even your own gif shows the eastern face of the top section is what becomes visible and does in fact topple off. Look how far East the collapse of the South Tower reaches. It goes far further East than it does West.

thedopefishlives said:

This is not necessarily true.

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It is when the pivot is not at the corner, which it isn't.

A block that is hinged at the corner will not have any part of itself moving up at any point.

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See above.

Of course, that is a mathematical idealization and hardly in any way realistic, but you're just trying to avoid the point: Downward motion and rotation are inextricably linked and difficult to differentiate.

Click to expand...

Not trying to avoid the "point" in the slightest. It's more pedantic JREF crap.

The point being...

cjnewson88 said:

1. The top section does not begin leaning over first. The top section begins a downwards motion at the same time, if not slightly before the top section begins leaning to the east.

Click to expand...

Nope. Rotation (with pedantic mathematical features applicable to a perfectly rigid structure aside) first, until perimeter failure progressed visibly from East to West, followed by West perimeter failure, at which point all four corner had released. At that point rotation continued, and vertical "fall" began. It's visible behaviour. Observable.

As I said, I'll dig out trace data for WTC2.

3 out of 4 of your assertions were incorrect.

I don't bother to engage in these "discussions" unless I've already looked at the behaviour in detail.

We can waste time dragging up years old research, but I suggest you readdress your OP.

femr2 said:

Rotation (with pedantic mathematical features applicable to a perfectly rigid structure aside)

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And, for that matter, relevant geometrical features equally applicable to a non-rigid structure...

Dave

cjnewson88 said:

This was what I was getting at. However I was also looking at the idea of whether there was any downwards motion before the tip began.

Click to expand...

Nope. West corner column fixed and in-place until North perimeter failure progressed from East to West...

I don't give the western pivot as much credit as others seem to.

Click to expand...

Credit or not, there is a pivot point, roughly around the West edge of the core. Opinions vary about exact location.

I would disagree.

Click to expand...

Disagree all you please good sir. But it IS the lower East perimeter, NOT the upper. End of. Many hours of observational study by multiple folk. Narrowed down to exact piece.

Look at your own .gif better

Click to expand...

No need. Looked at it for hours. Traced it. Generated it. Stabilised it. Rendered it in a 3D modeller, ...

the lower easter face is being smashed to piece well before that eastern face collapse becomes visible

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Incorrect.

To my observation, even your own gif shows the eastern face of the top section is what becomes visible and does in fact topple off.

Click to expand...

You need to correct your observation then.

Dave Rogers said:

And, for that matter, relevant geometrical features equally applicable to a non-rigid structure.

Click to expand...

Increasing pedantry.

femr2

Single best record of WTC2 early movement and behavior on the planet available at the following link:

3: Toward Accurate Collapse Histories


Guys, map first, ask questions later.

(Which is, of course, a variation of "shoot first, ask questions later", which has now become "drone first, ask questions later".)


You have to carefully map a complex deforming body before making global geometric assumptions.

femr2 said:

...Disagree all you please good sir. But it IS the lower East perimeter, NOT the upper. End of. Many hours of observational study by multiple folk. Narrowed down to exact piece....

Click to expand...

femr2 said:

Increasing pedantry....

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That blue sky approach is persistent.

Major_Tom said:

Single best record of WTC2 early movement and behavior on the planet available at the following link:

3: Toward Accurate Collapse Histories


Guys, map first, ask questions later.

(Which is, of course, a variation of "shoot first, ask questions later", which has now become "drone first, ask questions later".)


You have to carefully map a complex deforming body before making global geometric assumptions.

Click to expand...

There is literally no amount of facepalm that will suffice.

Listen.

This is the 9/11 Conspiracy Theory Forum.

WHERE IS YOUR CONSPIRACY?

Your math and graphs are all 100% dead on accurate. You have collected the best observables in the known UNIVERSE.

Now, the relevant question is, so what?
What.
Does.
It.
Mean?

Major_Tom said:

...You have to carefully map a complex deforming body before making global geometric assumptions.

Click to expand...

You could well be right on this specific instance M_T. Despite the ironic juxtaposition of your recognition of "global geometric assumptions" with your own global logical assumption implicit in the "have to"

The big issue being that it is a "complex deforming body" - a simple fact that many people from both extremes of the polarised WTC collapse discussion ignore leading them to false conclusions. The "Heiwanesque" rigid block claims being common bad examples. And the Tony Szamboti resurrection of Heiwanism in the "Can 15 floors crush one floor?" thread being the current active claim based on the same falsehood.

Given the complexity of the body and that it is deforming this is probably one of those situations where only measurements and observations can lead to the correct interpretation. It is not amenable to theoretical analysis and as always what was actually seen to happen should over-rule any theoretical considerations which disagree with valid observations.

NoahFence said:

There is literally no amount of facepalm that will suffice.

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Oncoming derail and rule 12 I reckon...

Listen.

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To the written word. Cool.

This is the 9/11 Conspiracy Theory Forum.

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Really ? I never knew that.

WHERE IS YOUR CONSPIRACY?

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Why are you addressing MT ?

He's simply provided the OP with information with which to correct his incorrect OP assertions with.

As has been bandied around here a bit recently (with no infractions raised)...why don't you go bust the OP's balls instead ?

Your math and graphs are all 100% dead on accurate. You have collected the best observables in the known UNIVERSE.

Click to expand...

I doubt MT would assert there's absolutely zero inaccuracy, but it's pretty expansive and detailed.

Now, the relevant question is, so what?
What.
Does.
It.
Mean?

Click to expand...

It's information which the OP can use as a reference and correct his erronious OP assertions.

Beyond that, speak to the OP

Thanks for the link Tom.

After a look, I correct myself slightly with observation 1. to the point which the top section does not begin to move downwards before it tilts, however I will stick with the obvious that the tilt was in sync with a downwards motion, even if that downwards motion is a result of the tilt itself, there is still a downwards action occurring.

I do however remain firm at this stage with the observation it is the upper east wall ejecting out and becoming visible part way through collapse. According to the gif used, for the object to be from the lower section, it would have to be remaining relatively stationary while the upper section just 'slides' in behind it for the beginning seconds of collapse. This just seems highly unlikely to me. Truth of the matter is, behind all that dust, we can only guess what is going on, however it seems far more likely to me that it is the east wall of the top section falling off.

That purple line shape comparing bit seems flawed in my opinion. The entire building was made up of those prefabricated sections of jigsaw like spandrels, drawing a purple line over some of them and saying 'it looks like this bit here' does not prove anything at all. I could just as easily draw a purple outline over a random part of the top section and say 'minus these two parts here, it's identical!'. Not very conclusive in my opinion.

femr2 said:

This is the 9/11 Conspiracy Theory Forum.

Click to expand...

Really ? I never knew that.

WHERE IS YOUR CONSPIRACY?

Click to expand...

Why are you addressing MT ?

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It is a reference to a false assumption. The criteria (? singular) for admission to this sub-forum is that the topic is about 9/11. It is not a requirement that it explicitly reference "conspiracy". ^{SEE BELOW} If that false premise applied then for consistency all of the Oystein, Ivan Kminek and ChrisMohr posts/threads about WTC Dust analyses would have to be banished to some other pure science area.

femr2 said:

Now, the relevant question is, so what?
What.
Does.
It.
Mean?

Click to expand...

It's information which the OP can use as a reference and correct his erronious OP assertions...

Click to expand...

It is a question which has been put many times to M_T in other situations BUT it is not relevant here. The info from M_T being validly on topic as I suggested in my post.

femr2 said:

...Beyond that, speak to the OP

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Definitely. The ongoing need to remember the topic and who raised the specific issue...

However the latter part of M_T's post could also be seen as gratuitous - adding nothing to this topic.

EDIT:

On review I think that my comment "The criteria (? singular) for admission to this sub-forum is that the topic is about 9/11. It is not a requirement that it explicitly reference "conspiracy". " is not quite accurate. It is too weak. The original intention, as I recall it being discussed, was that ALL 9/11 matters go into and stay in this sub forum.