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Funding sought to crash 747 into derelict building

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Funding sought to crash 747 into derelict building

Old 23rd Jul 2016, 10:29
  #441 (permalink)  
 
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megan, I have some more for your 3yo!





Real live action pyroclastic flow:




You've got to admit, the resemblance is uncanny *scary voice*


But this is nothing pyroclastic. It's just gravel and printer paper. And a few tonnes of pulverised concrete.


So this is actually just a dust cloud. Nothing pyroclastic. It may look bubbly like a volcano pyroclastic flow, but it's just the looks of it.

Dust cloud:


Sand storm:


Tiny little redneck dust cloud.


Kind of enjoying this thread, as I learn stuff I didn't know about before! Like, the difference between dust clouds and pyroclastic flows.

Thanks megan!
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Old 23rd Jul 2016, 11:35
  #442 (permalink)  
 
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Another thing puzzles me. Isn't controlled demolition generally done from the bottom up, not top down?
Surely it wouldn't work top down?
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Old 23rd Jul 2016, 13:48
  #443 (permalink)  
 
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andytug

Because I have no clue about controlled demolition techniques, I checked out some youtube compilations of this.

Trend seems to be the higher the building the more of the middle part is blasted away too.
Trend seems to be the centre of the building is blasted before the outer parts.
Trend seems to be the failed attempts blew out too much of the bottom first, which made the building tilt and topple over.

The narrower and higher the building, the more mid section blasts to make it into a neat pile of rubble without disturbing the surroundings. That seems to be the trend. I am not an expert so can just report trends, nothing more.

However, I find it peculiar that Landroger is so adamant WTC was a controlled demolition when by his own words 80% of the material was outside the actual building perimeter. Successful controlled demolitions seems to leave the surroundings unharmed. Doesn't add up.

Maybe it wasn't a controlled demolition, per se... more like a, you know, catastrophic failure thingy? Like, you know, uncontrolled? As if someone had just, well, I don't know, but let's say, someone, theoretically, maybe might have flown an airplane into the building and then fires had weakened the construction? Too easy an explanation?

(BTW it just occured to me that one of the pictures I used in the pyroclastic flow post shows very clearly how the steel outer structure is peeled off like a banana. Didn't notice that before. Again, this thread has made me aware of so many new things, I think I need a third major!)
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Old 23rd Jul 2016, 15:02
  #444 (permalink)  
 
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Yes, from what I've seen of demolitions they use smaller charges to break the upper part of the building up just a fraction before blowing the supports, thus the thing implodes into it's own base. Plus they generally go round for a couple of weeks or more beforehand chopping lumps out of critical supports and the like so the explosive doesn't have so much to do. (Mr Dibnah of course had a different method using fire, but same principle). Can't see any way of that happening in WTC.
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Old 23rd Jul 2016, 22:53
  #445 (permalink)  
 
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Lots of interesting photos and postings while Landroger is gone without his lappie.

I want to contribute several items starting with the very famous pyroclastic cloud as Landroger likes to call it, but really a dust cloud.

Landroger bases information and claims on this subject using information provided by Jim Hoffman, the computer web designer. Hoffman investigated the cloud to indicate there was not enough energy developed in the collapse of the WTC Tower to generate such cloud, therefore prepositioned munition like charges to initiate a controlled demolition had to be the reason for the collapse. His starting point was this photo:

He proceeds to make estimates of the volume of this cloud, and the expansion of it as an entity, starting from the volume of the towers. Along the way, he has to make numerous other estimates, including the average particle size of the cloud and so on. He claims at each stage to make a conservative estimate, and concludes his calculations thus:

‘The amount of energy required to expand the North Tower's dust cloud was many times the entire potential energy of the tower's elevated mass due to gravity. The over 10-fold disparity between the most conservative estimate and the gravitational energy is not easily dismissed as reflecting uncertainties in quantitative assessments.’
Hoffman doesn’t seem to be serious, as he reached version four of his analysis, which was supposed to replace his previous versions, but which he chose not to place on the internet (version four is at: The North Tower's Dust Cloud
and he has withdrawn all his estimates and calculations). There is no indication that his research has been submitted for publication and hence peer review by scientists competent to assess his estimates and calculations. All we can do at this stage is point out that his claim of the ten-fold disparity in energy requirements, as a conservative disparity, would require the conspirators to hide in the order of 5,000 tons of TNT equivalent in the Twin Towers, an equivalent of more than a third of the Hiroshima bomb. It is more likely however that his train of thought and assumptions are faulty, perhaps even his starting point in attempting to model the immense complexity of the dust cloud as the expansion of a discrete volume of gas.

Hoffman and Landroger definitely claim, without a doubt, WTC Building 7, a 40 story building, was demolished by controlled explosions, probably because the US government had offices in Building 7, and so there had to be a connection. Additionally Landroger claims the WTC Towers and WTC Building #7 were of the exact same design and construction, WTC Building #7 differed greatly from the WTC Towers. More about those differences later. No building in the US greater than 32 stories tall has ever been demolished by controlled explosions

As being discussed previously, there was a huge amount of energy developed by the collapse of the Towers, so much so that when the remains hit the ground, earthquake magnitudes of over 2.0 were recorded nearly 20 mille away from the tower’s location. To reiterate what others have said, what brought the towers down were two Boeing 767s hitting the towers at speeds approaching 490 miles per hour. The resulting fires and damage caused to multiple tower floors resulted in the damaged floors no longer being able to sustain the load of the undamaged floors above. So in the end, gravity brought the towers down. For Landroger’s benefit:

Newton, upon observing an apple fall from a tree, began to think along the following lines: The apple is accelerated, since its velocity changes from zero as it is hanging on the tree and moves toward the ground. Thus, by Newton's 2nd Law there must be a force that acts on the apple to cause this acceleration. Let's call this force "gravity", and the associated acceleration the "accleration due to gravity". Then imagine the apple tree is twice as high. Again, we expect the apple to be accelerated toward the ground, so this suggests that this force that we call gravity reaches to the top of the tallest apple tree.

The point is that controlled explosions or uncontrolled damage caused by two Boeing 767s hitting the building result in the same thing. Neither generate the energy gravity does, they are just enablers.

Landroger will claim that the towers were designed to withstand such an occurrence, as there was far more than adequate design margins factored into the tower design, as much as 200% more in some cases. What Landroger fails to grasp is that design margins are not absolute values, they are extremely dependent on assumptions of what could might failures. For example, the Titanic was designed in such a way with assumptions and design margins that it could not fail. It did, it sank. The launch vehicle carrying the Challenger was designed with assumptions and design margins that it could not fail, it blew up shortly after launch one morning. Airplanes are designed not to crash, but some occasionally do. Jet engines are designed not to fail but some occasionally do. Turbine blades are designed not to fail except some fail due to non detected defects in critical locations that weren’t accounted for in the design assumptions. Even automobile airbags designed to not inflate unless an impact is detected do inflate un-commanded as not all the assumptions that went into the design were adequate.

Gravity won out!
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Old 23rd Jul 2016, 23:05
  #446 (permalink)  
 
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andytug & MrSnuggles,

You are correct in the way controlled demolitions of buildings work. Here is an interesting site that explains it:

How Building Implosions Work | HowStuffWorks
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Old 24th Jul 2016, 09:38
  #447 (permalink)  
 
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Turbine D

What you just described about how this Hoffman person is calculating energy threw me off my chair. Noone should even ATTEMPT to do something that stupid! Who on earth allowed him to do this? How did he even think this was a good idea?

There are so many wrongs with that presumption, I can't even find the beginning of it.

The only, and I really mean ONLY, time you can use dust clouds to calculate energy is if you know EXACTLY what is in them, their exact chemical composition, density, air temperature, wind conditions, air pressure... thus it is only possible to do in a very controlled environment. Like a laboratory.

I guess I am preaching to the choir right now, and I am sure Landroger will find ways to claim Hoffman did a sterling job. But thanks anyway, Turbine D. Somehow I wonder, back in my mind, if quite a few of these conspiracy gentlemen come from Kansas. If you don't teach children to follow logic protocols, they of course grow up to adults who doesn't.
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Old 24th Jul 2016, 11:09
  #448 (permalink)  
 
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Child like fascination with a subject can be taken too far.

My mother explained to me that the sky is blue because it was the colour reflected back by the sea and there was more sea than land on the planet. That explanation sufficed for a three year old until a prism was obtained when I was five and I "discovered" white light was made up of many different colours.

If you haven't got the background knowledge or intuition, you cannot be expected to understand the real science explanation. It all just seems like magic.

Anyone else start out with the "How and Why Wonder Books" of science for kids? Marvellous for sparking curiosity and with good experiments you could do yourself for pocket money.
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Old 24th Jul 2016, 11:50
  #449 (permalink)  
 
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When I first saw Thunderbirds on TV as a child, it bothered me that T1 and T2 would come to a dead stop in mid-air and THEN fire their vertical lift motors. It also bothered me that the T3 launch cycle involved moving tons of low-sided swimming pool about a hundred yards to one side in a hurry, yet there were no signs of water spillage into the hangar below. I'd guess I was 7/8/9(?) at the time.

Many decades later I used video sequences from Thunderbirds while interviewing prospective grad apprentices, asking for a short list of technical bloopers. Those who didn't see them proceeded no further, because they lacked the intuitive feel and/or visualisation skills and would only ever be engineers who did things by cranking the handle or pure deduction (the latter group make excellent scientists, because of their unfettered thinking, but generally make poor engineers in my experience).

Incidentally - when I ran these exercises I would show the film clips and then ask for the bloopers, so they didn't know why it was being shown or what they were looking for. Over the years three candidates actually commented on the lift-motor thing with a chuckle while the film was running - they did indeed become very good engineers.

The "missing energy" thing is amusing. Landroger mentioned it a few pages back and I responded with something about not being confident in how I could sketch out a method to estimate this energy to any significant degree of confidence or precision, but (as with most things) this went way over his head, poor thing.

But he and his fellow loons have not addressed the single greatest issue with any theory of controlled demolition - it would have involved (as a minimum) hundreds of people in planning and execution. The US government has shown itself to be completely incapable of keeping secret things secret. So why has NO ONE come forward and said "I carried 2 of the 5,000 tonnes of C4 into the building and attached it myself!"?

Final point.

In both towers the collapse initiates on the same floors as the sites of the aircraft impacts. If it was a controlled demolition that means that:

1. All the explosives were places on no more than two or three of about six floors.

2. The demolition control system, fuses, cabling, detonators etc were extremely rugged so that they could survive both the impact damage and the ensuing fire, and yet still trigger together on demand. That's pretty impressive demolition engineering.

3. The explosives would have to have been placed in advance, and then each aeroplane would have to have been flown into those specific floors. Now that really IS a difficuly piece of precision flying.

So in balance, the overall conclusion is that those believing these theories are just sad, attention-seeking loons who can only ever deserve our pity.

PDR
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Old 24th Jul 2016, 12:13
  #450 (permalink)  
 
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The thing is, they don’t smash all fifteen floors and then start on the next. The process happens at most, one floor at a time and, as I pointed out to TURIN, some 80% of the building – and thus 80% of every floor – ended up outside the footprint and was thus not available to crush anything
Well of course it ended up outside the footprint. If it didn't you would still have a tower stood there.
Ever played Jenga? The blocks tend to spread all over the table on collapse.
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Old 24th Jul 2016, 16:37
  #451 (permalink)  
 
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The heap of rubble should have formed essentially a bell curve of debris on the ground after a vertical collapse. So quite a bit of debris would be expected to fall outside the building footprint. Exactly what was seen.
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Old 24th Jul 2016, 19:53
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An aerial view of the rubble around WTC Towers 1 & 2, WTC #7 is a little different because of its construction design.
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Old 25th Jul 2016, 13:26
  #453 (permalink)  
 
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Turbine D

I had nothing better to do so I randomly googled for images of controlled demolitions. Again, I majored in Engineering Physics and Materials Science, but never studied controlled demolitions per se, so I can only comment on trends. That said; this is the trend when downing taller buildings.

As you can see, they blast out the middle section to make it fall into the underlying parts, while removing the ground support at the bottom. The close proximity to the houses nearby makes me believe the rubble pile will resemble nothing like your post above from the WTCs. It also seems they go for one side of the building first (to the left) to further limit damage done outside the actual building area.



Notice that there are living quarters nearby. It would be awfully expensive to fight the lawsuits if those were to be damaged. And again, the trend of blasting in the middle sections. I would guess they do this to gather momentum so it can crush everything below it.



Positively awesome before and after pictures of a real controlled demolition!
Aerial before & after of New Walk Centre demolition | Central - ITV News

Before:


After (different angle, orientate with the big red building with green roof):



Certainly a lot of debris everywhere... kind of, you know, well, more like... un-controlled, maybe..?

Last edited by MrSnuggles; 25th Jul 2016 at 13:29. Reason: layout cock ups
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Old 25th Jul 2016, 23:30
  #454 (permalink)  
 
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Thanks for those controlled demolition photos, MrSnuggles.

Now about WTC Building #7, let me give Landroger some homework to do upon his return.

Landroger,
1. What exactly do you object to (all your significant points) in the NIST report on the collapse of WTC #7?

2. Why is the NIST analysis on the collapse using ANSYS in error?

3. Would you dispute the comments/conclusions of the following source of building demolitions? Why?

From Implosionworld.com, a worldwide publication source for news and building controlled demolitions, blowdowns, and other types of structural blasting projects.


THE WORLD TRADE CENTER COLLAPSE
Questions & Answers

Implosionworld.com has received numerous inquiries from around the world requesting information and commentary relating to the terrorist attacks of September 11th, 2001, and specifically the felling of the World Trade Center towers. We have been contacted by media outlets, structural engineers, schoolteachers, conspiracy theorists and many others who are searching for answers and some “perspective” regarding these significant events that have evoked deep emotions and undoubtedly changed our world forever.

The editors of implosionworld.com have created this page to answer a few of the most frequently asked questions that fall within our area of knowledge and expertise. But first we’d like to be clear in stating that any conversation relating to “implosions” and what causes structures to fail is undertaken with reverence and respect to those who perished as a result of this event. As many of our frequent web visitors are aware, Implosionworld.com’s offices are located close to New York City, and several of our employees were personally touched by this tragedy. Our thoughts and prayers remain with the families of those lost and injured, and our intent here is to help foster a constructive base of knowledge and understanding through education, while dispelling false rumors related to the attack.


DID THE WORLD TRADE CENTER TOWERS ACTUALLY “IMPLODE”?
No. They collapsed in an uncontrolled fashion, causing extensive damage to surrounding structures, roadways and utilities. Although when viewed from a distance the towers appeared to have telescoped almost straight down, a closer look at video replays reveal sizeable portions of each building breaking free during the collapse, with the largest sections--some as tall as 30 or 40 stories--actually “laying out” in several directions. The outward failure of these sections is believed to have caused much of the significant damage to adjacent structures, and smaller debris caused structural and cosmetic damage to hundreds of additional buildings around the perimeter of the site.

WHY DID THEY COLLAPSE?
Each 110-story tower contained a central steel core surrounded by open office space, with 18-inch steel tubes running vertically along the outside of the building. These structural elements provided the support for the building, and most experts agree that the planes impacting the buildings alone would not have caused them to collapse. The intense heat from the burning jet fuel, however, gradually softened the steel core and redistributed the weight to the outer tubes, which were slowly deformed by the added weight and the heat of the fire. Eventually, the integrity of these tubes was compromised to the point where they buckled under the weight of the higher floors, causing a gravitational chain reaction that continued until all of the floors were at ground level.

DID THE TERRORISTS PLANT ANY BOMBS IN THE BUILDINGS IN ADVANCE TO GUARANTEE THEIR DEMISE?
To our knowledge there is no evidence whatsoever to support this assertion. Analysis of video and photographs of both towers clearly shows that the initial structural failure occurred at or near the points where the planes impacted the buildings. Furthermore, there is no visible or audible indication that explosives or any other supplemental catalyst was used in the attack.

HOW DOES THIS EVENT COMPARE WITH A NORMAL BUILDING IMPLOSION?
The only correlation is that in a very broad sense, explosive devices (airplanes loaded with fuel) were used to intentionally bring down buildings. However it can be argued that even this vague similarity relates more to military explosive demolition than to building implosions, which specifically involve the placement of charges at key points within a structure to precipitate the failure of steel or concrete supports within their own footprint. The other primary difference between these two types of operations is that implosions are universally conducted with the utmost concern for adjacent properties and human safety---elements that were horrifically absent from this event. Therefore we can conclude that what happened in New York was not a “building implosion.”

ARE THERE ANY PLANS TO EXPLOSIVELY DEMOLISH THE REMAINS OF NEARBY BUILDINGS?
Not at this time, and probably not in the future. Engineering officials have expressed concern over the risk of causing additional damage to sensitive underground liabilities such as subway tunnels and below-grade retaining walls. Therefore any future demolition activities will likely be performed piecemeal, using heavy equipment.

Editor's update 12/20/01- With the removal of the 8-story U.S. Custom's House yesterday morning, all condemned structures have now been removed from the site. Explosives were not used in these operations.

HOW HAVE THE EXPLOSIVES-USING INDUSTRIES BEEN AFFECTED?
Immediately following the attack, the U.S. Department of Alcohol, Tobacco and Firearms (ATF) and other international regulatory agencies suspended all transportation and delivery of explosives. This caused temporary disruptions within the quarrying and construction industries as well as the postponement of several high-profile explosive demolition projects in the United States and Europe (although it should be noted that all of these projects, including the DFW Hyatt Hotel, Jordan Thorpe Towers and Roby-Huntington Bridge, among others, were eventually rescheduled and successfully completed in October 2001). In the interim, the ATF issued warnings related to the reporting of suspicious activities near explosives storage and distribution areas, as well as an advisory regarding the transportation of hazardous materials and the commencement of non-routine visits to persons and locations where explosives are stored and used. It can also be reasonably assumed that other safeguards will be implemented that are not announced to the public.

HOW WILL THIS EVENT AFFECT EXPLOSIVE DEMOLITION IN THE FUTURE?
Although the full effect of these events remains to be seen, certain changes are already taking place. In the short term there will be tighter security on jobsites and stricter regulations on the use and transportation of explosives as mentioned above. Liability insurance will also likely become an issue, as an anticipated rise in rates may affect the economic viability of explosive demolition as an alternative to conventional methods. But perhaps the largest question involves public perception and society’s continued acceptance of building implosions in general, particularly as “entertainment.” It is recognized that there will always be select situations where explosive demolition is viewed as the safest and most effective way to raze a given structure. However industry experts will be watching to see whether the compelling visual allure of these events continues to be successfully exploited as promotional spectacle like many are today, or if the thunderous noise, energy and dust emanating from giant structures crashing to the ground bring forth latent mental images of terror and suffering. History tells us that strong emotions dissipate with time, and that they eventually come to pass. But history has never experienced an event--or an era--quite like this.
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Old 26th Jul 2016, 06:04
  #455 (permalink)  
 
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When this post finally Dies and goes to Heaven, I will be really sad, I enjoy..neigh I really enjoy reading the info so contained..its become my morning Third Habit.................

I cannot wait for the next conspirator theory..
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Old 26th Jul 2016, 06:38
  #456 (permalink)  
 
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Hi,

The other primary difference between these two types of operations is that implosions are universally conducted with the utmost concern for adjacent properties and human safety---elements that were horrifically absent from this event. Therefore we can conclude that what happened in New York was not a “building implosion.”
Weird comment ......
Assuming that this would be attackers that have participated (planted explosives) in the destruction of the towers .. I do not think they would be concerned not to further damage or minimal victims
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Old 26th Jul 2016, 08:21
  #457 (permalink)  
 
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Originally Posted by Peter-RB View Post
When this post finally Dies and goes to Heaven, I will be really sad, I enjoy..neigh I really enjoy reading the info so contained..its become my morning Third Habit.................

I cannot wait for the next conspirator theory..
I think it won't die a natural death - it will have been killed off as an inside job by CIA black-ops cyber-ninjas...



PDR
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Old 26th Jul 2016, 10:13
  #458 (permalink)  
 
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The main objection I have to all this is that I can't see any government or agency of the government being clever enough to set sure how a thing up and execute it and keep it a secret, given the number of people that would have to be involved. History is littered with examples of where people have tried and failed with far less complex plots, as government and its agencies tend to muck things up, usually in a big way.
Either that or it's Scientology and the lizards.
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Old 26th Jul 2016, 10:24
  #459 (permalink)  
 
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PDR1

A great great great movie to enjoy with engineering students is that stupid one with Liv Tyler and a bunch of oil drillers who goes into space and blows up some asteroid. I watched this with running commentary (from myself and other interested) about the stupidness that was Hollywood physics.

Another abomination from the Hollywood physics department is The Core, where Earth's core stops and they need to drill inside to nuke blast it into motion again.
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Old 26th Jul 2016, 10:34
  #460 (permalink)  
 
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andytug

Yes, those gouvernment secret plots are always exposed in some way, sooner or later - more often than not; sooner. There's always that chap who can't shut up. Or a police officer with too many questions. Or journalists that doesn't care about the easy mushy-fluffy human interest stories and instead goes into the rabbit hole. Or a combination of those three.

Setting up explosive devices for downing huge buildings is an immense job, I have come to understand. Arranging them only for smaller buildings, like 15 stories, are hard enough and takes a lot of time to get it right.

And why need explosives when there are planes flying straight into the buildings? That in itself is enough cause for concern, I believe.
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