Analysis of Rocket Projectiles from WTC2
I have uploaded to YouTube (http://www.youtube.com/watch?v=xvw0_i1rGns) an analysis of the acceleration of a projectile that races ahead of the surrounding falling debris. I had discussed this object before but due to the difficulty caused by a moving camera I had not previously measured the motion directly.
The object (apparently a perimeter wall unit) raced ahead of its neighboring debris, but its acceleration was about 1/3 of gravity. This is an indication that it was kicked downward initially by an explosion, after which the air resistance partially canceled the effect of gravity as it approached terminal velocity. As it fell, however, there was an outburst of white smoke, at which point the projectile changed directions, slightly, and accelerated downward for about a half second at 1.5 times gravity. It then fell back to continued acceleration a little under 1 g.
The acceleration of the projectile is unambiguous proof that very energetic material was applied to the wall unit. What I found particularly surprising is that the ignition of the material in an unconfined space where it was free to expand three dimensionally would provide sufficient thrust due to expanding gasses alone to cause what was probably a 4-ton wall unit to accelerate 50% faster than gravity. The fact that the unit continued to accelerate close to freefall thereafter is an indication of an ongoing thrust capable of largely canceling the effect of air resistance.
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Well done David!
Objects falling faster than freefall are yet another physical impossibility with the official story.
Of course we can expect the debunkers to say: "Well if you average the downward motion of that 4 ton segment starting from the time when the tower was first built to Sept 11 2001, its downward acceleration is hardly noticeable and certainly not even close to freefall!"
By What Measure Is Freefall Speed Determined For Video?
Is the estimated speed of the object relative to leading edge of collapse debris (assumed to be descending at freefall) or distance traveled per elapsed time? If measured with respect to the other debris, one should consider that much of the neighboring debris seems to be in the form of dust or lightweight exterior aluminum cladding, which quite likely will descend at a rate less than freefall due to air resistance.
Another explanation may be that the comparatively heavier noted object was the first to emerge from the lighter debris cloud while naturally falling faster to the ground than these lighter neighboring collapse materials. Admittedly, the movement of the object seems unusual.
I would expect a force (from the source of the white smoke at the end of the object?) capable of accelerating this possibly multi-ton object as hypothesized, to also cause this object to tumble end over end like a wayward rocket without directional control. However, the object seems to barely be rotating during its descent. While the white smoke or dust may be evidence of a thermitic reaction, I'm somewhat skeptical that it represents a propelling energy capable of generating movement of a multi-ton object beyond freefall acceleration.
The white smoke or dust only seems to be trailing behind the object as opposed to being evidence of thrust..
However, I don't doubt that the WTC was purposely demolished through some use of nano-scale incendiaries/explosives. 20-25% of a once motionless upper structure should not naturally cause the directly adjacent 75-80% of the lower structure to shatter into thousands of pieces all the way to the ground naturally.
In my opinion, the white puffs from the lower floors of WTC 2 during collapse in the video, are evidence of aluminum oxide associated with thermitic reactions, likely being expelled by a collpase related "bicycle pump" effect. There is not evidence of fires on these floors, which of course would generate much darker smoke, not white smoke.
"Admittedly, the movement of
"Admittedly, the movement of the object seems unusual".
Bizarrely unusual. Once an object is in free fall, the only force (outside of the relatively very small influence of air resistance and the <15kt wind ... a horizontal vector) acting upon it is gravity, which only acts vertically downwards, and is also a constant.
An object which suddenly speeds up to 1.5g *must* have been influenced by another force, ie not gravity, not wind and not a change in air resistance. The falling piece in the video also does not appear to have been in collision with anything (which would slow it down and/or alter its direction, and not speed it up).
The only force that can alter the trajectory of the falling object seen in the video is something capable of not only violent gaseous emission but must also be physically attached to the object.
What other forces, outside of energetic materials attached to the object, are capable of altering the trajectory of a free-falling object? Judy Woods type fantasies are not a solution here, and nobody shot anything at the object from above to speed it up. (!)
Debunkers are going to have a hell of a time explaining this in terms that are acceptable to their way of thinking.
Measurement of acceleration
"Is the estimated speed of the object relative to leading edge of collapse debris (assumed to be descending at freefall) or distance traveled per elapsed time?"
It is not measured relative to the other debris. It is measured relative to the pixels which have been stabilized relative to the background.
...
"Another explanation may be that the comparatively heavier noted object was the first to emerge from the lighter debris cloud while naturally falling faster to the ground than these lighter neighboring collapse materials."
You have no basis for assuming this piece is any heavier than the rest of the debris. The rest of the debris is the rest of the building, which includes a whole lot of steel. Also, heavier debris does not "naturally" fall faster. This piece was thrown downward initially by a violent event and gets another kick which is associated with a puff of white smoke.
"I would expect a force (from the source of the white smoke at the end of the object?) capable of accelerating this possibly multi-ton object as hypothesized, to also cause this object to tumble end over end like a wayward rocket without directional control. However, the object seems to barely be rotating during its descent. While the white smoke or dust may be evidence of a thermitic reaction, I'm somewhat skeptical that it represents a propelling energy capable of generating movement of a multi-ton object beyond freefall acceleration."
Something is clearly propelling the object downward, changing its acceleration from ~3 m/s^2 to ~15 m/s^2.
Object Ejection Rate Due To Collapse Related Compression?
It seems possible that the object ejection rate was quite possibly due to the sudden commpressive force created by the collpasing upper structure interacting with a secured object. Although, such an ejection would likely also generate observable rotation of an object. It seems difficult to discern a mid-flight acceleration.
"You have no basis for assuming this piece is any heavier than the rest of the debris. The rest of the debris is the rest of the building, which includes a whole lot of steel. Also, heavier debris does not "naturally" fall faster."
Most would agree that except for the steel structures, the building's contents were shredded or pulverized. A change in size and dimensions of these contents could make them more subject to drag, creating a lower descent rate for the majority of the demolition wave contents, than that of steel columns for example. A bowling ball will reach the ground before a beach ball or dust.
"It is measured relative to the pixels which have been stabilized relative to the background."
It would seem that a frame playback rate would impact object speed measurements, although acceleration can still be noted regardless of playback rate, as long as frame durations are equal. Given the potential for even a minor playback rate difference from an actual object movement rate, a more reliable speed gauge might be in order.
Speculative objections
So far all objections amount to speculation. If the playback frame rate is claimed to be variable enough to cause measurement deviations, one should prove it. If there are valid critiques of the measurement methodology, one should put forth such critiques in a verifiable and reproducible way.
I haven't seen any plausible explanation for the over-g acceleration of this object so far beyond referral to fictional mechanisms. An object does not accelerate over g without a mechanism, such as rotation around a pivot or a spring effect. If you drop a book, such as the 9/11 Commission Report, off of a tower and it rotates along its center of mass, even disregarding drag, the book still does not exceed g. There could be other reasons for the accelerative behavior of this object, certainly. But Chandler has done measurements, which can be replicated, (and should) while his critics so far haven't done anything of the sort. I await better critiques.
If you want to test physical laws…
...I don’t suggest using the 9/11 report. We know for sure that physical laws do not apply on the inside and I fear they may not work on the outside either. Besides, it’s full of holes which makes it a real drag.
But seriously, I have not seen any objections yet that says it’s not falling significantly faster then “g”. Could it have been nanothermite inside those box columns blasting out the hand hole? Was it some mechanical cutter charge placed inside or outside, blasting away? We may never know, but the fact that it’s falling faster than “g” is all we really need to know for sure, for that is impossible with a fire induced “collapse”. Certainly, double checking these measurements would be wise.
Brainstorming objections
I agree that there are no well thought out objections on this page: it's all about brainstorming possible objections. I think Chandler's argument already looks convincing and the object was already a curios one before Chandler pointed out its anomalous downward acceleration. But I'd like to learn more about these issues:
- An estimate of the error bars for the measurement of larger than g acceleration.
- Some thought into whether vertical/horizontal rotation can explain the change in motion and downward acceleration
- An estimate of vertical and horizontal rotation
- Some kind of thought into whether the object started rotating vertically due to an asymmetrical downward force, or whether somehow the force acted symmetrically on the girder in which case one should wonder why smoke apparently appears only on one side.
All these points are not clear to me and I only raise them in order to help provide some humble "peer review".
Thanks David!!!
Visualizing Exponentially
Having recovered an ability to visualize exponentially, it is apparent that the issue is a sustained rate of change of velocity as opposed to a rate of change of position.
The object acceleration seems quite strange. Perhaps an analysis can be done to see if at any time, the object dust is being expelled from the object as opposed to trailing away.
WOW!!!
This is a really good find! Congratulations!
Debunkers are no doubt going to attack this. To preempt that I'd like to already put in some thought about the precision of the measurement. The measurement demonstrating larger acceleration than free-fall is based on 3 points in the plot. There should be a good response to a "debunker claim" that the precision to determine the acceleration is insufficient. Is it possible to include more points and perhaps do some statistical analysis?
Can one do some statistical analysis here to rule out any claim that the supergravitational acceleration is just measurement noise?
I agree that this might seem like overkill... but debunkers are debunkers...
Again, very exciting news!
Interesting find
Interesting find, though I'd agree with Haze. If possible, more data points would be nice, as well as error bars.
Time interval used
In most of my videos I use 0.2 second intervals for velocity computations. The original data are ~30 frames per second, but numerical differentiation is an inherently "noisy" process, especially when the amount of motion involved is comparable to the pixel measurement error. Trying to extract more precision leads only to cluttering the picture with more noise.
it's okay to have noise
In any measurement it is important to have an idea of the magnitude of the noise. Even if you feel the noise is insignificant compared to your signal, it is still important to include it, usually in the form of error bars.
Without error bars, it is very difficult for someone reviewing your work to determine whether the different slopes are measurement error or actually a result of different accelerations. The need for error bars in the graph
you have presented is particularly strong since only 3 data points (the bare minimum) were used in determining the slope.
Cluttering up the graph with more noise (by using additional data points) is okay, because it will also give a better idea of the amount of noise in the measurement.
Numerical differentiation
What method did you(or the program) use? Did you consider higher order methods
http://en.wikipedia.org/wiki/Numerical_differentiation ?
Perhaps these might help in increasing the number of points?
Differentiation of noisy functions
Have a look here for more advanced methods for differentiating "noisy functions":
http://www.holoborodko.com/pavel/numerical-methods/numerical-derivative/
Or just google "numerical differentiation noisy function".
If you haven't used methods like these I would think that you can improve the data analysis and end up with more data points. I would also expect that these methods of numerical differentiation comes with estimates of error bars as well.
State of The Art, Spring 2002
http://ammtiac.alionscience.com/pdf/AMPQ6_1.pdf
See page 43, Figure 1 for the ways nanocomposites were being used. Propellant and Explosive.
"Currently, a class of energetic materials known as nitramines are actually used for both explosives and propulsion applications in various weapons systems."
"Very simply, nanoenergetics can store higher amounts of energy than conventional energetic materials and one can use them in unprecedented ways to tailor the release of this energy so as
to maximize the lethality of the weapons."
In the last part of the video
it looks like the object is spinning, and one end in particular is smoking.
Thus if you are tracking the acceleration of the smoke source, you may be mislead by the spinning. Put another way, it may be risky to assume the acceleration of the smoke source is the same as the acceleration of the center of mass, if that is what you're doing.
Good point!
A rotating object would have a sinusoidal modulation of the acceleration of one end, perhaps the smoking end. However, if that is the case the time scale associated with the rotation must coincide with the time scale associated with the the "supergravitational" acceleration peak measured by Chandler.
The time scale associated with the acceleration peak can be directly read off from Chandlers plot and seems to be around 0.5 seconds, if I'm not mistaken!
So the question is then: are these two time scales roughly the same?
Then there is also the change in horizontal motion as depicted in Chandlers video. Can that also *potentially* be explained by a rotating object? The spatial curve does not seem to be sinusoidal as it should be if this was a rotating object. But more analysis is perhaps needed to make sure.
Kevin,
If you look at the last video clip in Chandlers presentation you see that the object seems to be rotating horizontally and not vertically. Therefore, if the two videos indeed depict the same object, it does not seem possible to "explain away" the "supergravitational acceleration" as due to vertical rotation of the object.
However, the horizontal rotation could perhaps be considered in relation to the change in horizontal motion.
Haze, I agree
that the object appears to be rotating in the horizontal plane, at least late in the video. If it is, the vertical acceleration analysis is sufficient, as you point out.
Still, the analysis could still be criticized since it is a long object with smoke coming from one end. The force would then be applied at this end, I guess, with a somewhat unclear direction. But how could a force accelerate it downward, without spinning the object in a vertical plane?
At least, it's fair to say that models using point masses and idealized forces can have limitations.
Center of mass acceleration
I think the critical issue is the supergravitational acceleration. Since the object is rotating horizontally this seems to be a serious problem with any fire-based explanation. I'd like to see more data points if possible so as to make absolutely clear that this is not just measurement error. Chandler is careful so I expect that he already has thought about that issue.
By Newton's laws we know that any force F acting on a body will cause the center of mass x_{cm} to accelerate according to F=m a_{cm} where a_{cm} is the acceleration of the center of mass: it does not matter where the force is applied. So I would maintain that there is no limitation in this regard. But your point is well taken: an asymmetric downward "propulsion force" causing the acceleration to be about 50% larger than free-fall, would cause the girder start rotating vertically.
Apparently we do not see this. Why? Perhaps the propulsion is not asymmetric? But then I would expect smoke to come from all the girder; not just one end. One also have to take into account the timing of the propulsion and the state of rotation before as compared with after the supergravitational acceleration peak.
Another brick in the wall of evidence
Yet another piece of evidence, amongst so many others, that point to explosives, and away from what NIST have said. If only more Americans were scientifically literate....
Education is being dumbed down
There is a trend for that here in the UK.
A higher percentage of kids are getting top grades yet businesses and universities are saying school leavers are illiterate.
But I digress...
Doing your own analysis
I am not the only one capable of doing this kind of analysis. All the software is out there and free. If you try some of this on your own you would get a much better feel for the power and limitations of the technique. Here is a tutorial I put together for my students:
http://911speakout.org/wp-content/uploads/Tracker-How-To.pdf
I would add that for rectifying the images I use The Gimp (Gnu Image Manipulation Program, or you could use Photoshop). I use Avidemux to split the video into images, import the images "As Layers" into The Gimp or Photoshop, then use one image as a reference and move the others around until the background lines up. I turn off all but two layers at a time and blink the little "eye" icon to detect any relative shift. Then I save each layer as a separate image and use Avidemux to reassemble them into a video, or simply import the sequence of images into Tracker directly.
David, maybe this
is another vid to have a crack at in the future. Just stumbled upon this, never seen it before. It shows very graphically the outer skeleton being ripped apart in rapid fashion from top to bottom:
http://www.youtube.com/watch?feature=player_detailpage&v=V0tzmGgWggg
Thanks for all your work.
Awesome!
I reported on this find 2009 in this comment here: http://911blogger.com/news/2009-08-29/south-tower-exploding-projectile#comment-215530
Overkill
Just wanted to make a few reflections. It seems that the building was brought down by overkill. The pulverization of the concrete is an example. There may have been redundant systems to ensure that the buildings would reliably destruct. Note the tremendous percentage of thermitic material found in the dust, much of it unexploded. Yet what did explode, truly pulverized the building. I think about this because most building demolitions do not leave a pool of molten material, or extremely hot debris over a wide area in the building foot print, that I know of. But this did. I mentioned in other comments that there is a relationship between the heat and the work done, and it is not merely the conversion of heat into work, but also the transfer of heat from a hotter to a cooler body. The efficiency of this process varies, but is a maximum in a reversible process. Obviously the demolition of the towers was an inefficient, irreversible process, and would thus require the transfer of a greater quantity of heat. There seems to have been no official attempt to explain the large amount of heat generated by the collapses. In sum, much more energy was employed in bringing down the towers than in an ordinary controlled demolition, and the use of this much energy could not be hidden.