stundie:
Thanks for your comments, .... much appreciated..... Yes, the worst "offenders" at JREF, (in my opinion), are enigma, tsig, pardalis, and lashl. These posters are quite incapable of making any positive contributions to the 9/11 debate! And this is my main criticism of them. I don't mind people having contrary views to mine; as long as they do nothing to harm me or my family, they can believe what they want! I would even say that people's views on art, science, religion and politics is what makes life interesting. But I am deeply bothered by the group of JREF posters named above who only know how to spew venom. Of late enigma cannot get beyond calling truthers "inhuman scum," for example!
And stundie you are correct: Ms. Robertshaw (Lashl) is a JREF forum donor. But she is also a civil litigation lawyer who works for the city where I live (Hamilton). My taxes help to pay her salary and she has boasted somewhat gleefully in a post on JREF that she sometimes goes on the JREF Conspiracy thread from her office at work. Now when I worked for the government we were strictly forbidden from using our office computers for personal business or entertainment. Apparently, here in Hamilton, if you are a lawyer working for City Hall, anything goes!
And to Grumpy I must say that you need to lighten up and stop talking about MY scientific integrity. I tried to expose a serious case of scientific fraud involving a Canadian University back in 1995... the subsequent legal battles taught me a lot about scientific integrity; but I can tell you I never compromised mine! So who says you have the moral high ground in the great 9/11 debate. I may not agree with stundie, or newton or metamars or lozenge124, but I respect their right to their views. If I believe they are using "bad science" I will tell them. And if they think I'm full of it, I'm sure they will tell me,... I can handle it, .... I'm a big boy now!
NEU-FONZE --- I'm a bit puzzeled by your list of questions about the collapse initiation. I had thought essentially all was understood.
Briefly, the buckling of the south wall (WTC 1) initiated the overloads on the remainder of the stucture. Crush-down ensued.
Briefly, the buckling of the south wall (WTC 1) initiated the overloads on the remainder of the stucture. Crush-down ensued.
QUOTE (einsteen+Jul 4 2008, 10:26 AM)
Your toolset must be big, how do you make that ?
http://i32.tinypic.com/hra1cx.gif
impressive!
ps. I stopped using rapidshare (you can download only one file per time period), megaupload doesn't have that limit...
Thanks. Let the laws of motion be administered by a physics engine! Just playing around right now, but the approach does show promise for helping to understand fairly simple systems that are nonetheless analytical nightmares. After NEU-FONZE mentioned the pencil I read a page that went through the derivation of the equation of motions. Then I started from scratch and did the same thing for a cube pendulum rotating about an edge, first using torques and angular accelerations then a Lagrangian formulation. Naturally, both led to the same result which is the general form of a pendulum but with severe angles. The pencil, just being inverted from the normal type, can employ small 'infinitesimal' displacement to simplify the process of seeking a solution.
At that point, I had to throw my hands up because, you know, it's the classical physics conundrum: the only way we get an analytical solution to harmonic oscillators like this is to first assume the oscillator has infinitesimal motion about equilibrium (i.e., is NOT in motion). I was content to note the form of theta double-dot conforms to intuitive expectations about free rotation of a cube about an edge, starting with horizontal orientation. Add in a generalized resistive force and the solution will include both sinusoidal appearance (though not of the phase of the pencil) and the character of the resistive force - which might bring back the pencil-like appearance for a different reason.
My hope is to use simulations to examine specific aspects of the mechanics of structure disintegration. It is somewhat unsatisfying that numerical analysis is required for the mechanics of all but the most trivial systems, but what can you do? While I can't analytically solve the equations of motion of hundreds or thousands of coupled bodies, each physics engine and simulator I use is going to provide one such numerical solution, for what it's worth.
I appreciate the conversion to GIF, I have a new machine and have set up very little except what it takes to code and build the simulation app and write out an AVI. And thanks for the tip about Megauploader. The download limitations are a bit of a drag on Rapidshare.
http://i32.tinypic.com/hra1cx.gif
impressive!
ps. I stopped using rapidshare (you can download only one file per time period), megaupload doesn't have that limit...
Thanks. Let the laws of motion be administered by a physics engine! Just playing around right now, but the approach does show promise for helping to understand fairly simple systems that are nonetheless analytical nightmares. After NEU-FONZE mentioned the pencil I read a page that went through the derivation of the equation of motions. Then I started from scratch and did the same thing for a cube pendulum rotating about an edge, first using torques and angular accelerations then a Lagrangian formulation. Naturally, both led to the same result which is the general form of a pendulum but with severe angles. The pencil, just being inverted from the normal type, can employ small 'infinitesimal' displacement to simplify the process of seeking a solution.
At that point, I had to throw my hands up because, you know, it's the classical physics conundrum: the only way we get an analytical solution to harmonic oscillators like this is to first assume the oscillator has infinitesimal motion about equilibrium (i.e., is NOT in motion). I was content to note the form of theta double-dot conforms to intuitive expectations about free rotation of a cube about an edge, starting with horizontal orientation. Add in a generalized resistive force and the solution will include both sinusoidal appearance (though not of the phase of the pencil) and the character of the resistive force - which might bring back the pencil-like appearance for a different reason.
My hope is to use simulations to examine specific aspects of the mechanics of structure disintegration. It is somewhat unsatisfying that numerical analysis is required for the mechanics of all but the most trivial systems, but what can you do? While I can't analytically solve the equations of motion of hundreds or thousands of coupled bodies, each physics engine and simulator I use is going to provide one such numerical solution, for what it's worth.
I appreciate the conversion to GIF, I have a new machine and have set up very little except what it takes to code and build the simulation app and write out an AVI. And thanks for the tip about Megauploader. The download limitations are a bit of a drag on Rapidshare.
QUOTE (lozenge124+Jul 4 2008, 01:45 PM)
That's great! I look forward to more of your simulations.
What software are you using?
Thank you. I added breakable fixed joints (connections) after that post, so now walls can be walls and not stacks. I hope the future will bring some interesting stuff.
That was done using the PhysX SDK (formerly AEGIA and now under NVIDIA). There's no application software, just a library and you write your own C++ code to create the scene, set the parameters and so forth. I'm also working with ChronoEngine, IBDS, TrueAxis and a couple of others as basic physics engines but the professional nature of PhysX justs makes it easier to use. The collection can be integrated into layers under a common implementation using Physics Abstraction Layer (all this stuff is free, by the way). These are game engines, for sure, and not industrial-strength FEM libraries, but I believe the higher quality engines can do a pretty decent job of modeling exemplar behavior of certain simple dynamical situations. You have to be aware of the limitations, intimately, and be very careful in your setup to avoid nonsense results... and take it for what it is: much better than any BS I could implement!
In fact, the solvers for PhysX and IBDS in particular are exceptional, and certainly rival ANY sort of simulator from a couple of decades ago. Yes, there are situations where you can get a stupefying amount of artifact but, for a lot of things (like pendulums, buckling, collsions of ensembles of objects, etc.) you can get the basic feel for the behavior of a system. My goal here is to characterize the behavior of idealized dynamic systems with many constituents of few types and simple structure.
Since these engines are developed for game purposes, the emphasis is on speed over accuracy and there are certain clever non-physical tricks to get stability and convergence that work for games but are utterly meaningless in the real world. I've found that avoiding the tricks and using small time steps and many iterations produces some pretty accurate results for well-conditioned problems. The simulation frame rate is quite slow (even with PhysX GPU and quad core CPU) but I just capture the OpenGL buffer into frames and make a movie. The main thrust however, will be examining overall dynamics and distribution of energies and momenta over time of various constituents and aggregates. I will use multiple engines on the same systems for comparison.
I need to understand stochastic quasi-fluid properties of medium size ensembles of structural components. In doing so, I may contruct models decidedly non-physical in superficial appearance. This is easier/cheaper than crushing tinkertoy models in my garage (yes, Arthur, I was kidding about that, but when it comes down physical validation of computer models, who knows).
What software are you using?
Thank you. I added breakable fixed joints (connections) after that post, so now walls can be walls and not stacks. I hope the future will bring some interesting stuff.
That was done using the PhysX SDK (formerly AEGIA and now under NVIDIA). There's no application software, just a library and you write your own C++ code to create the scene, set the parameters and so forth. I'm also working with ChronoEngine, IBDS, TrueAxis and a couple of others as basic physics engines but the professional nature of PhysX justs makes it easier to use. The collection can be integrated into layers under a common implementation using Physics Abstraction Layer (all this stuff is free, by the way). These are game engines, for sure, and not industrial-strength FEM libraries, but I believe the higher quality engines can do a pretty decent job of modeling exemplar behavior of certain simple dynamical situations. You have to be aware of the limitations, intimately, and be very careful in your setup to avoid nonsense results... and take it for what it is: much better than any BS I could implement!
In fact, the solvers for PhysX and IBDS in particular are exceptional, and certainly rival ANY sort of simulator from a couple of decades ago. Yes, there are situations where you can get a stupefying amount of artifact but, for a lot of things (like pendulums, buckling, collsions of ensembles of objects, etc.) you can get the basic feel for the behavior of a system. My goal here is to characterize the behavior of idealized dynamic systems with many constituents of few types and simple structure.
Since these engines are developed for game purposes, the emphasis is on speed over accuracy and there are certain clever non-physical tricks to get stability and convergence that work for games but are utterly meaningless in the real world. I've found that avoiding the tricks and using small time steps and many iterations produces some pretty accurate results for well-conditioned problems. The simulation frame rate is quite slow (even with PhysX GPU and quad core CPU) but I just capture the OpenGL buffer into frames and make a movie. The main thrust however, will be examining overall dynamics and distribution of energies and momenta over time of various constituents and aggregates. I will use multiple engines on the same systems for comparison.
I need to understand stochastic quasi-fluid properties of medium size ensembles of structural components. In doing so, I may contruct models decidedly non-physical in superficial appearance. This is easier/cheaper than crushing tinkertoy models in my garage (yes, Arthur, I was kidding about that, but when it comes down physical validation of computer models, who knows).
QUOTE (newton+Jul 4 2008, 06:41 PM)
how about this piece of spaghetti?
newton, you come up with some great videos. I've got a tower 100 blocks high that looks like that when it falls over from its inherent instability and small initial perturbations. Never quite the same thing twice, but the same general appearance; I'll get a video up at some point.
The simulations are interesting. I've seen those before. It really depends on the math and assumptions behind the graphics as to whether it's just a rendering of some solution or a modeling of any physical behavior, and a further question of accuracy wrt the towers. Obviously there's some disagreement between this person's model/results and others we've seen. I'd like to see how those solutions were obtained, because I can make my own movie right now but it would be meaningless. The key is the dataset driving the graphics.
As to your point about the modeling being 'too hard', I fully agree. It's absurd to think having a mesh for each column, spandrel and connection is necessary to model aspects of structural disintegration and correlate them. As usual, big problems can be broken down into smaller, more manageable ones. I'm using free tools, writing my own code to run on a PC, and nobody's paying me a dime. Granted, I'm not going to be churning out displacement numbers over time but, from this perspective, I find excuses of complexity to be quite lame.
newton, you come up with some great videos. I've got a tower 100 blocks high that looks like that when it falls over from its inherent instability and small initial perturbations. Never quite the same thing twice, but the same general appearance; I'll get a video up at some point.
The simulations are interesting. I've seen those before. It really depends on the math and assumptions behind the graphics as to whether it's just a rendering of some solution or a modeling of any physical behavior, and a further question of accuracy wrt the towers. Obviously there's some disagreement between this person's model/results and others we've seen. I'd like to see how those solutions were obtained, because I can make my own movie right now but it would be meaningless. The key is the dataset driving the graphics.
As to your point about the modeling being 'too hard', I fully agree. It's absurd to think having a mesh for each column, spandrel and connection is necessary to model aspects of structural disintegration and correlate them. As usual, big problems can be broken down into smaller, more manageable ones. I'm using free tools, writing my own code to run on a PC, and nobody's paying me a dime. Granted, I'm not going to be churning out displacement numbers over time but, from this perspective, I find excuses of complexity to be quite lame.
Quote: NEU-FONZE
"I now believe that the upper block did not drop one floor and hit the structure below. I and others may have used this idea in calculations of the collapse times, but for me it was an approximation I made to simplify the math! The upper block was connected to the lower block by at least 40 core columns and hundreds of perimeter columns. The load of the upper block could not be suddenly taken off the lower structure; thus the upper block could not drop under free fall onto the structure below."
The central premise of Gordon Ross's hypothesis considered the remaining core connectivity inherent in the impact zone (rather than the lack there of). He believed, that the heat effect would have, if anything, facilitated the process of "plastic deformation", therefore dissipating more and enhancing less, the acceleration component of the available PE. WTC1 had more core damage, but less mass (upper section). WTC2 had less (total) core damage, but more mass. Either way, a component of the force equation is in deficit. Ross contends that the presence of residual cores would result in some degree of arrested collapse, assuming that no other mechanism was not in effect.
Whether I resonate with each and every nuance posted by NEU FONZE, his well written and reasoned posts are always source a pleasure to read. I aspire myself, to someday express myself with such clarity and dignity.
"I now believe that the upper block did not drop one floor and hit the structure below. I and others may have used this idea in calculations of the collapse times, but for me it was an approximation I made to simplify the math! The upper block was connected to the lower block by at least 40 core columns and hundreds of perimeter columns. The load of the upper block could not be suddenly taken off the lower structure; thus the upper block could not drop under free fall onto the structure below."
The central premise of Gordon Ross's hypothesis considered the remaining core connectivity inherent in the impact zone (rather than the lack there of). He believed, that the heat effect would have, if anything, facilitated the process of "plastic deformation", therefore dissipating more and enhancing less, the acceleration component of the available PE. WTC1 had more core damage, but less mass (upper section). WTC2 had less (total) core damage, but more mass. Either way, a component of the force equation is in deficit. Ross contends that the presence of residual cores would result in some degree of arrested collapse, assuming that no other mechanism was not in effect.
Whether I resonate with each and every nuance posted by NEU FONZE, his well written and reasoned posts are always source a pleasure to read. I aspire myself, to someday express myself with such clarity and dignity.
Disclaimer:
This CAD simulation explores stress modalities, post impact, among other things. At the 4:37 (time code) point, it introduces simulated speculation of a planned controlled demolition, and at the 9:24 point it, unfortunately, suggests a nuke in the basement scenario. If I could have edited the latter out, I would have, as it distracts from an otherwise interesting video.
0:00 to 4:37, however, ties in with the latest thoughts of NEU FONZE and my last post, and it is for that part of the video that I provide it.
WTC Finite Element Analysis
http://www.youtube.com/watch?v=ExmSMU9ls-w&feature=related
This CAD simulation explores stress modalities, post impact, among other things. At the 4:37 (time code) point, it introduces simulated speculation of a planned controlled demolition, and at the 9:24 point it, unfortunately, suggests a nuke in the basement scenario. If I could have edited the latter out, I would have, as it distracts from an otherwise interesting video.
0:00 to 4:37, however, ties in with the latest thoughts of NEU FONZE and my last post, and it is for that part of the video that I provide it.
WTC Finite Element Analysis
http://www.youtube.com/watch?v=ExmSMU9ls-w&feature=related
Grumpy:
Let's talk some more about the NIST Report. How much was based on physical evidence and how much on computer modeling? And let's be honest Grumpy, the "models" we are talking about are mere simulacra. Stuff that would certainly NOT hold up in court. No, Grumpy, I am talking about REAL FORENSIC EVIDENCE used by NIST, ... you know, stuff like chemical analyses.
So let's look at the chemical analyses that were used by NIST:
Well, what do you know, ...... The NIST Report manages one table of data, yes, just ONE TABLE on the composition of recovered steel surfaces in 10,000 pages of documentation. And that table provides data for 3 samples! And does NIST have much to say about these data? Well actually, no …, not really. NIST comments on the high S seen on a couple of samples, but completely ignores the high Cl observed on sample K-16. The high S is never explained, ....and the high Cl is not even mentioned in the text even though it is potentially important and possibly key to the collapse of the towers.... But let's not jump the gun!
So NIST really makes no use of what little chemical analysis data it managed to collect on WTC samples. But where is the chemical analysis data for even a couple of failed welds and bolts? And where is the analytical data for the concrete?
So NIST really only relies on modeling. But, just for fun, let's look at one of NIST's modeling efforts:
NIST’s aircraft impact modeling is a good one: If you read NCSTAR 1-2, 1-2B, 1-5A and 1-6 you find all sorts of discrepancies between the observed behavior of the aircraft, the impact debris and NIST’s global impact analysis. NIST argue that the fuel was almost completely aerosolized within 0.5 seconds of impact, but in reality fuel is known to have poured down elevator shafts. NIST’s model says that, with the exception of the engines and undercarriage, the aircraft were shredded into “thousands of fragments”. This is contradicted by the large sections of fuselage that were found outside the towers with nary a scratch! Then we have the trajectories of the engines themselves which came out all wrong in NIST’s initial simulations until those creative computer programmers “tweaked” the calculations to make an engine exit WTC 2 as observed. In what sense is NIST being scientific with all these false predictions of its models?
And does the aircraft impact model consider any physico-chemical effects caused by alumino-thermic processes? No? I thought not!
So, Grumpy: "Let us not talk falsely now, the hour is getting late".
Let's talk some more about the NIST Report. How much was based on physical evidence and how much on computer modeling? And let's be honest Grumpy, the "models" we are talking about are mere simulacra. Stuff that would certainly NOT hold up in court. No, Grumpy, I am talking about REAL FORENSIC EVIDENCE used by NIST, ... you know, stuff like chemical analyses.
So let's look at the chemical analyses that were used by NIST:
Well, what do you know, ...... The NIST Report manages one table of data, yes, just ONE TABLE on the composition of recovered steel surfaces in 10,000 pages of documentation. And that table provides data for 3 samples! And does NIST have much to say about these data? Well actually, no …, not really. NIST comments on the high S seen on a couple of samples, but completely ignores the high Cl observed on sample K-16. The high S is never explained, ....and the high Cl is not even mentioned in the text even though it is potentially important and possibly key to the collapse of the towers.... But let's not jump the gun!
So NIST really makes no use of what little chemical analysis data it managed to collect on WTC samples. But where is the chemical analysis data for even a couple of failed welds and bolts? And where is the analytical data for the concrete?
So NIST really only relies on modeling. But, just for fun, let's look at one of NIST's modeling efforts:
NIST’s aircraft impact modeling is a good one: If you read NCSTAR 1-2, 1-2B, 1-5A and 1-6 you find all sorts of discrepancies between the observed behavior of the aircraft, the impact debris and NIST’s global impact analysis. NIST argue that the fuel was almost completely aerosolized within 0.5 seconds of impact, but in reality fuel is known to have poured down elevator shafts. NIST’s model says that, with the exception of the engines and undercarriage, the aircraft were shredded into “thousands of fragments”. This is contradicted by the large sections of fuselage that were found outside the towers with nary a scratch! Then we have the trajectories of the engines themselves which came out all wrong in NIST’s initial simulations until those creative computer programmers “tweaked” the calculations to make an engine exit WTC 2 as observed. In what sense is NIST being scientific with all these false predictions of its models?
And does the aircraft impact model consider any physico-chemical effects caused by alumino-thermic processes? No? I thought not!
So, Grumpy: "Let us not talk falsely now, the hour is getting late".
QUOTE (Grumpy+Jul 4 2008, 08:53 AM)
I know the NIST reports are not perfect, however, there will NEVER be a better scientific study done due to the paucity of the physical evidence (not NIST's fault, they were called in late). Once first responders determined that the cause was not explosives the scene was treated as a disaster site, not a crime scene. Rescue and recovery were their primary goals, not preservation of forensic evidence.
Grumpy,
I'm a bit confused....
Once first responders determined that the cause was not explosives, how did they rule out non-explosive modes of collapse initiation?
...Or did first responders simply jump to conclusions?
Max
Grumpy,
I'm a bit confused....
Once first responders determined that the cause was not explosives, how did they rule out non-explosive modes of collapse initiation?
...Or did first responders simply jump to conclusions?
Max
Zoktoberfest:
Thanks for the comments,.... and the video. Yes, the first part is interesting, but the second part ....(???)
Max Photon:
Looks like your "scientific" thread was censored over at JREF,... hardly a surprise, but it was up long enough for me to witness enigma drinking from the same cup of vitriol usually imbibed by lashl!
Sad really, that "adults" should be doing such things, but a copy of what was said is now safe with me.
Thanks for the comments,.... and the video. Yes, the first part is interesting, but the second part ....(???)
Max Photon:
Looks like your "scientific" thread was censored over at JREF,... hardly a surprise, but it was up long enough for me to witness enigma drinking from the same cup of vitriol usually imbibed by lashl!
Sad really, that "adults" should be doing such things, but a copy of what was said is now safe with me.
Max Photon
Who said they did???
The first responders were interested more in rescue of survivors, not forensic investigations. Once cleared of the dangers of further explosions the why was the last thing on their minds, they worried about that afterward.
NEU-FONZE
Who said they did???
The first responders were interested more in rescue of survivors, not forensic investigations. Once cleared of the dangers of further explosions the why was the last thing on their minds, they worried about that afterward.
NEU-FONZE
Let's talk some more about the NIST Report.
Yeah, I'm tired of wasting time on "Thermite" BS and energy beams from space.
Well, since reliable physical evidence was limited and a lot of that was ambiguous as to being pre or post collapse, NIST HAD to rely on computer models using the rather limited physical evidence of initial conditions.
Well, since reliable physical evidence was limited and a lot of that was ambiguous as to being pre or post collapse, NIST HAD to rely on computer models using the rather limited physical evidence of initial conditions.
And let's be honest Grumpy, the "models" we are talking about are mere simulacra.
Just like modeling of Fluid Dynamics or Stellar Evolution are facsimiles, FEA using the past experience to inform them ARE NOT WILD A$$ GUESSES but are SOUND SCIENTIFIC METHODS!!!
So, how do you tell if such chemical traces are caused by pre collapse fires, or a result of post collapse reactions??? Imagine, Chlorides coming from SEAWATER, UNHEARD OF!!!(NOT).
So, how do you tell if such chemical traces are caused by pre collapse fires, or a result of post collapse reactions??? Imagine, Chlorides coming from SEAWATER, UNHEARD OF!!!(NOT).
NIST argue that the fuel was almost completely aerosolized within 0.5 seconds of impact, but in reality fuel is known to have poured down elevator shafts.
Atomization is NOT a permanent condition. Large scale atomization(over 10,000 gallons) will inevitably lead to large scale condensation and return to liquid conditions(in nature, we call it rain!).
So??? Take a look at size distribution in ANY commutation event. You will have a range of sizes and of damage to those pieces. And look at what you are calling "large sections of fuselage", a few windows in a section of fuselage skin. Other than the engines, landing gear and other "hard" pieces" VERY LITTLE of those aircraft were intact or unscathed.
So??? Take a look at size distribution in ANY commutation event. You will have a range of sizes and of damage to those pieces. And look at what you are calling "large sections of fuselage", a few windows in a section of fuselage skin. Other than the engines, landing gear and other "hard" pieces" VERY LITTLE of those aircraft were intact or unscathed.
Then we have the trajectories of the engines themselves which came out all wrong in NIST’s initial simulations until those creative computer programmers “tweaked” the calculations to make an engine exit WTC 2 as observed.
You mean NIST actually adjusted initial conditions until the outcome of the sims actually matched the observed reality??? Oh No!!!
Again, of what use is a sim that DOESN'T conform to reality, other than to tell you that initial conditions are off??? NONE, of course!!! Once the outcomes match what is actually observed, you are at least in the ballpark, and NIST was honest about their methods and the expected range of error. You don't have a valid point here, just a quibble.
Again, of what use is a sim that DOESN'T conform to reality, other than to tell you that initial conditions are off??? NONE, of course!!! Once the outcomes match what is actually observed, you are at least in the ballpark, and NIST was honest about their methods and the expected range of error. You don't have a valid point here, just a quibble.
And does the aircraft impact model consider any physico-chemical effects caused by alumino-thermic processes? No? I thought not!
And just what evidence is there of these reactions??? Yes, they are possible, but the point is they make the damage done MORE severe, not less, collapse MORE likely, not less. And NIST has made a good case that what they DID consider was enough to bring those towers down. Again, NIST was VERY conservative and avoided speculation, you do not have a valid quibble here either.
Yeah, that was my point about these quibbles. Your criticisms in no way invalidate the NIST conclusions, in fact they enhance their case with ADDITIONAL modes of damage!!! Sort of like stabbing someone after they have already been fatally shot!!!
And you need to make this plain to your troother friends!!!
Grumpy
PS See, I can argue logically with those who are logical.
Anyway, only works for WTC 2, and maybe not even there.
QUOTE
Once first responders determined that the cause was not explosives, how did they rule out non-explosive modes of collapse initiation?
Who said they did???
The first responders were interested more in rescue of survivors, not forensic investigations. Once cleared of the dangers of further explosions the why was the last thing on their minds, they worried about that afterward.
NEU-FONZE
QUOTE (->
| QUOTE |
| Once first responders determined that the cause was not explosives, how did they rule out non-explosive modes of collapse initiation? |
Who said they did???
The first responders were interested more in rescue of survivors, not forensic investigations. Once cleared of the dangers of further explosions the why was the last thing on their minds, they worried about that afterward.
NEU-FONZE
Let's talk some more about the NIST Report.
Yeah, I'm tired of wasting time on "Thermite" BS and energy beams from space.
QUOTE
How much was based on physical evidence and how much on computer modeling?
Well, since reliable physical evidence was limited and a lot of that was ambiguous as to being pre or post collapse, NIST HAD to rely on computer models using the rather limited physical evidence of initial conditions.
QUOTE (->
| QUOTE |
| How much was based on physical evidence and how much on computer modeling? |
Well, since reliable physical evidence was limited and a lot of that was ambiguous as to being pre or post collapse, NIST HAD to rely on computer models using the rather limited physical evidence of initial conditions.
And let's be honest Grumpy, the "models" we are talking about are mere simulacra.
Just like modeling of Fluid Dynamics or Stellar Evolution are facsimiles, FEA using the past experience to inform them ARE NOT WILD A$$ GUESSES but are SOUND SCIENTIFIC METHODS!!!
QUOTE
So let's look at the chemical analyses that were used by NIST:
Well, what do you know, ...... The NIST Report manages one table of data, yes, just ONE TABLE on the composition of recovered steel surfaces in 10,000 pages of documentation. And that table provides data for 3 samples! And does NIST have much to say about these data? Well actually, no …, not really. NIST comments on the high S seen on a couple of samples, but completely ignores the high Cl observed on sample K-16. The high S is never explained, ....and the high Cl is not even mentioned in the text even though it is potentially important and possibly key to the collapse of the towers.... But let's not jump the gun!
Well, what do you know, ...... The NIST Report manages one table of data, yes, just ONE TABLE on the composition of recovered steel surfaces in 10,000 pages of documentation. And that table provides data for 3 samples! And does NIST have much to say about these data? Well actually, no …, not really. NIST comments on the high S seen on a couple of samples, but completely ignores the high Cl observed on sample K-16. The high S is never explained, ....and the high Cl is not even mentioned in the text even though it is potentially important and possibly key to the collapse of the towers.... But let's not jump the gun!
So, how do you tell if such chemical traces are caused by pre collapse fires, or a result of post collapse reactions??? Imagine, Chlorides coming from SEAWATER, UNHEARD OF!!!(NOT).
QUOTE (->
| QUOTE |
| So let's look at the chemical analyses that were used by NIST: Well, what do you know, ...... The NIST Report manages one table of data, yes, just ONE TABLE on the composition of recovered steel surfaces in 10,000 pages of documentation. And that table provides data for 3 samples! And does NIST have much to say about these data? Well actually, no …, not really. NIST comments on the high S seen on a couple of samples, but completely ignores the high Cl observed on sample K-16. The high S is never explained, ....and the high Cl is not even mentioned in the text even though it is potentially important and possibly key to the collapse of the towers.... But let's not jump the gun! |
So, how do you tell if such chemical traces are caused by pre collapse fires, or a result of post collapse reactions??? Imagine, Chlorides coming from SEAWATER, UNHEARD OF!!!(NOT).
NIST argue that the fuel was almost completely aerosolized within 0.5 seconds of impact, but in reality fuel is known to have poured down elevator shafts.
Atomization is NOT a permanent condition. Large scale atomization(over 10,000 gallons) will inevitably lead to large scale condensation and return to liquid conditions(in nature, we call it rain!).
QUOTE
NIST’s model says that, with the exception of the engines and undercarriage, the aircraft were shredded into “thousands of fragments”. This is contradicted by the large sections of fuselage that were found outside the towers with nary a scratch!
So??? Take a look at size distribution in ANY commutation event. You will have a range of sizes and of damage to those pieces. And look at what you are calling "large sections of fuselage", a few windows in a section of fuselage skin. Other than the engines, landing gear and other "hard" pieces" VERY LITTLE of those aircraft were intact or unscathed.
QUOTE (->
| QUOTE |
| NIST’s model says that, with the exception of the engines and undercarriage, the aircraft were shredded into “thousands of fragments”. This is contradicted by the large sections of fuselage that were found outside the towers with nary a scratch! |
So??? Take a look at size distribution in ANY commutation event. You will have a range of sizes and of damage to those pieces. And look at what you are calling "large sections of fuselage", a few windows in a section of fuselage skin. Other than the engines, landing gear and other "hard" pieces" VERY LITTLE of those aircraft were intact or unscathed.
Then we have the trajectories of the engines themselves which came out all wrong in NIST’s initial simulations until those creative computer programmers “tweaked” the calculations to make an engine exit WTC 2 as observed.
You mean NIST actually adjusted initial conditions until the outcome of the sims actually matched the observed reality??? Oh No!!!
QUOTE
In what sense is NIST being scientific with all these false predictions of its models?
Again, of what use is a sim that DOESN'T conform to reality, other than to tell you that initial conditions are off??? NONE, of course!!! Once the outcomes match what is actually observed, you are at least in the ballpark, and NIST was honest about their methods and the expected range of error. You don't have a valid point here, just a quibble.
QUOTE (->
| QUOTE |
| In what sense is NIST being scientific with all these false predictions of its models? |
Again, of what use is a sim that DOESN'T conform to reality, other than to tell you that initial conditions are off??? NONE, of course!!! Once the outcomes match what is actually observed, you are at least in the ballpark, and NIST was honest about their methods and the expected range of error. You don't have a valid point here, just a quibble.
And does the aircraft impact model consider any physico-chemical effects caused by alumino-thermic processes? No? I thought not!
And just what evidence is there of these reactions??? Yes, they are possible, but the point is they make the damage done MORE severe, not less, collapse MORE likely, not less. And NIST has made a good case that what they DID consider was enough to bring those towers down. Again, NIST was VERY conservative and avoided speculation, you do not have a valid quibble here either.
QUOTE
So, Grumpy: "Let us not talk falsely now, the hour is getting late".
Yeah, that was my point about these quibbles. Your criticisms in no way invalidate the NIST conclusions, in fact they enhance their case with ADDITIONAL modes of damage!!! Sort of like stabbing someone after they have already been fatally shot!!!
And you need to make this plain to your troother friends!!!
Grumpy
PS See, I can argue logically with those who are logical.
Grumpy:
Two points:
1. Please see the paper by P.B. Maciejczyk et al. at the New York University School of Medicine published in the American Chemical Society monograph: “Urban Aerosols and their Impacts: Lessons learned from the World Trade Center Tragedy” ACS Symposium, 2003. In a study of soluble ionic species and pH of suspensions of bulk WTC settled dust, these authors report that chloride was the dominant species detected (after Ca and SO4), in all particle size classes and the Cl was NOT well correlated with Na. The authors conclude that other chlorinated compounds, “produced by the fire”, were present in the dust. Nitrate ion was another major species detected, especially in the fine fractions of dust samples, and was “highly correlated” with ammonium ion.”
2. Might I also recommend that you take a look at public domain reports by S. R. Tieszen who appears to be a world authority on jet fuel dispersal in post-crash situations. He has made some videos of liquid fuel dispersal under impact tests. These tests show a distinct difference in fuel dispersion behavior between low velocity, (less than 20 m/s), and high velocity, (above 50 m/s) impacts. At high velocities the fuel is completely atomized into a fine mist. The same tests showed that, regardless of the impact angle, no liquid pooling occured at 61 m/s and 91 m/s impacts.
Other tests are noted by Tieszen:
"In the 200 m/s impact velocity range, the wing structure does not qualitatively change the dispersal process. The fuel is finely atomized and no pooling will occur."
So what's the use of a model where fuel "droplets" are 1 liter and an atomized fuel mist is supposed to have drained to lower levels!
Two points:
1. Please see the paper by P.B. Maciejczyk et al. at the New York University School of Medicine published in the American Chemical Society monograph: “Urban Aerosols and their Impacts: Lessons learned from the World Trade Center Tragedy” ACS Symposium, 2003. In a study of soluble ionic species and pH of suspensions of bulk WTC settled dust, these authors report that chloride was the dominant species detected (after Ca and SO4), in all particle size classes and the Cl was NOT well correlated with Na. The authors conclude that other chlorinated compounds, “produced by the fire”, were present in the dust. Nitrate ion was another major species detected, especially in the fine fractions of dust samples, and was “highly correlated” with ammonium ion.”
2. Might I also recommend that you take a look at public domain reports by S. R. Tieszen who appears to be a world authority on jet fuel dispersal in post-crash situations. He has made some videos of liquid fuel dispersal under impact tests. These tests show a distinct difference in fuel dispersion behavior between low velocity, (less than 20 m/s), and high velocity, (above 50 m/s) impacts. At high velocities the fuel is completely atomized into a fine mist. The same tests showed that, regardless of the impact angle, no liquid pooling occured at 61 m/s and 91 m/s impacts.
Other tests are noted by Tieszen:
"In the 200 m/s impact velocity range, the wing structure does not qualitatively change the dispersal process. The fuel is finely atomized and no pooling will occur."
So what's the use of a model where fuel "droplets" are 1 liter and an atomized fuel mist is supposed to have drained to lower levels!
NEU och David,
I would have emmigrated here if it wasn't so hard to follow a topic among the many topics on this single thread. Here's a link to the new forum I started.
The 9/11 Forum
Not much going on yet, but those posting here might appreciate having more than one thread and stricter rules than here or JREF. The forum is not "open registration" and we will be filtering out the nuts, nasties and intellectually challenged. I have invited a number of people from the "Scholars for 9/11 Truth and Justice" forum and from JREF. The JREFers I have invited are some of the more knowlegable and polite ones. Our moderation policy will be enforced without regard to creed and any typical JREF tactics will result in suspension or banning.
I hope some of you will consider the new forum as a complement to this forum. No reason not to link between them to relevant posts!
/Gregory U.
I would have emmigrated here if it wasn't so hard to follow a topic among the many topics on this single thread. Here's a link to the new forum I started.
The 9/11 Forum
Not much going on yet, but those posting here might appreciate having more than one thread and stricter rules than here or JREF. The forum is not "open registration" and we will be filtering out the nuts, nasties and intellectually challenged. I have invited a number of people from the "Scholars for 9/11 Truth and Justice" forum and from JREF. The JREFers I have invited are some of the more knowlegable and polite ones. Our moderation policy will be enforced without regard to creed and any typical JREF tactics will result in suspension or banning.
I hope some of you will consider the new forum as a complement to this forum. No reason not to link between them to relevant posts!
/Gregory U.
QUOTE (stundie+Jul 4 2008, 01:41 PM)
If you need to see an example of this bias, then look no further than this current thread where Red Ibis is being attacked and labelled as an Anti-Semite by none other than the ranting, foaming at the mouth Pomeroo and others, even though Red Ibis as never made a single derogatory remarked about Jewish people or their religion.
That's typical Jref, you're an Anti-Semite, you love the terrorists, but if you don't think they are fully responsible then you are a racist, because Arabs are intelligent and educated people who certainly can fly a plane. btw RedIbis told a while ago that he is Jewish.
Neu,
I also used my work's computer to post...but I'm not working for the government and I need internet for my job and hopefully for my next job also although in my probation period I will try to avoid 911'ing. And thanks for your list I think you could add a couple more, maybe pomeroo...
All,
Is it a good idea to let this thread die and all go to Greg's forum ? here we have no inline pictures and it is unorganized as been discussed before...
That's typical Jref, you're an Anti-Semite, you love the terrorists, but if you don't think they are fully responsible then you are a racist, because Arabs are intelligent and educated people who certainly can fly a plane. btw RedIbis told a while ago that he is Jewish.
Neu,
I also used my work's computer to post...but I'm not working for the government and I need internet for my job and hopefully for my next job also although in my probation period I will try to avoid 911'ing. And thanks for your list I think you could add a couple more, maybe pomeroo...
All,
Is it a good idea to let this thread die and all go to Greg's forum ? here we have no inline pictures and it is unorganized as been discussed before...
I'll keep checking in here, almost daily, for whoever might show up.
Gregory:
I hope you don't mind me saying this, but the trouble with a website that claims to be "fair", or well-moderated, is that such a claim is very subjective. I mean JREF claims to be "fairly moderated", but where's the evidence for this. I have looked, believe me, ... I have looked, ..... but all I see is authoritarian bias. Anonymity is the only thing those JREF guys value!
In fact JREF is the antithesis of "fair moderation" as we all know, ...... a disgrace, not that I care...
But my point is that we have all heard horror stories about people being banned from some "Conspiracy" site or another. Thus even I, a retired professional scientist, could tell you all about my banning at an "EDUCATIONAL SITE", ... a banning brought about by ....... well you know I could write a book about it, ..... but it's just another "bad moderator" story.
So, Gregory, be very careful when you claim that your site will be well-moderated.
Anyway, I must say that PhysOrg is an exceptionally well-run, "moderator friendly" site, which is a good thing, ....... which is why I am happy to post here.
But this doesn't mean I won't check out other sites.
Don't cry for me JREF, the TRUTH is, I never joined you!
I hope you don't mind me saying this, but the trouble with a website that claims to be "fair", or well-moderated, is that such a claim is very subjective. I mean JREF claims to be "fairly moderated", but where's the evidence for this. I have looked, believe me, ... I have looked, ..... but all I see is authoritarian bias. Anonymity is the only thing those JREF guys value!
In fact JREF is the antithesis of "fair moderation" as we all know, ...... a disgrace, not that I care...
But my point is that we have all heard horror stories about people being banned from some "Conspiracy" site or another. Thus even I, a retired professional scientist, could tell you all about my banning at an "EDUCATIONAL SITE", ... a banning brought about by ....... well you know I could write a book about it, ..... but it's just another "bad moderator" story.
So, Gregory, be very careful when you claim that your site will be well-moderated.
Anyway, I must say that PhysOrg is an exceptionally well-run, "moderator friendly" site, which is a good thing, ....... which is why I am happy to post here.
But this doesn't mean I won't check out other sites.
Don't cry for me JREF, the TRUTH is, I never joined you!
Shut Up and Get In Line
By Max Photon
Am I the only one
Who finds it amusing
That those with the biggest brain
Form an infinite train
That renders simple perusing
A mental drain and bruising?
By Max Photon
Am I the only one
Who finds it amusing
That those with the biggest brain
Form an infinite train
That renders simple perusing
A mental drain and bruising?
Quote: NEU FONZE
"NIST argue that the fuel was almost completely aerosolized within 0.5 seconds of impact, but in reality fuel is known to have poured down elevator shafts.
Quote: GRUMPY
"Your criticisms in no way invalidate the NIST conclusions, in fact they enhance their case with ADDITIONAL modes of damage!!! Sort of like stabbing someone after they have already been fatally shot!!!
NEU FONZE
You have put me in the awkward position of having to agree with someone like Grumpy.
Although, I am not yet prepared to retract my compliment, I do find myself confused about some of your perspectives. Newton, as I recall, placed a lens in the thought stream of your "king's men" commentary and projected it back on you. Perhaps, my compliment should have included elements of elegant ambivalence.
I'm hardly in a position to question your apparent vacillation, because I've been all over the road when speculating on the events of 9/11 myself. I, however, naturally relate more to invention than engineering; to free association than deconstruction. Your science and technical writing background, however, place you in the handful of elite that post on this thread. Unlike my incidental status, you command center stage.
So, when you challenge the official speculation, that the surviving vertical infrastructure had lost all capacity to further redistribute the (gravity) load, ears perk up, at least mine did. I followed up your comments with reference, but the discussion, it appears, is already in the rear view mirror. What was the purpose of your declaration?
When the use of thermite first began to be considered, I recall being the first (at least here) to speculate that a thermo-baric reaction would be an effective method for ignition. Aerosolized components, released into designated elevator shafts from the mechanical rooms above would, post ignition, send plasma pressure waves past the drywall and into core and joist areas coated with thermite laden (faux) fireproofing. It was creative, but being just speculation, it got what I suppose it deserved, no traction.
Shortly there after, "the magic jet fuel" theory, an uncertain reaction playing out in uncertain conditions, as compared to an optimized thermo-baric set-up, was put forth to account for the series of explosions, smoke, fire, and destruction reported in the lower parts of the buildings around the time of impact, and thereafter.
The "the magic jet fuel", however, was also just speculation, but it was adopted, retroactively, as part of the "official" account to explain anomalies, even though NIST concluded that the fuel was mostly aerosolized. Now you are diseminating it as fact, giving credence, back, to the hodge podge known as the official account.
NF, I don't understand where you are going with your latest commentary. It seems as if you are playing both sides against the middle.
"NIST argue that the fuel was almost completely aerosolized within 0.5 seconds of impact, but in reality fuel is known to have poured down elevator shafts.
Quote: GRUMPY
"Your criticisms in no way invalidate the NIST conclusions, in fact they enhance their case with ADDITIONAL modes of damage!!! Sort of like stabbing someone after they have already been fatally shot!!!
NEU FONZE
You have put me in the awkward position of having to agree with someone like Grumpy.
Although, I am not yet prepared to retract my compliment, I do find myself confused about some of your perspectives. Newton, as I recall, placed a lens in the thought stream of your "king's men" commentary and projected it back on you. Perhaps, my compliment should have included elements of elegant ambivalence.
I'm hardly in a position to question your apparent vacillation, because I've been all over the road when speculating on the events of 9/11 myself. I, however, naturally relate more to invention than engineering; to free association than deconstruction. Your science and technical writing background, however, place you in the handful of elite that post on this thread. Unlike my incidental status, you command center stage.
So, when you challenge the official speculation, that the surviving vertical infrastructure had lost all capacity to further redistribute the (gravity) load, ears perk up, at least mine did. I followed up your comments with reference, but the discussion, it appears, is already in the rear view mirror. What was the purpose of your declaration?
When the use of thermite first began to be considered, I recall being the first (at least here) to speculate that a thermo-baric reaction would be an effective method for ignition. Aerosolized components, released into designated elevator shafts from the mechanical rooms above would, post ignition, send plasma pressure waves past the drywall and into core and joist areas coated with thermite laden (faux) fireproofing. It was creative, but being just speculation, it got what I suppose it deserved, no traction.
Shortly there after, "the magic jet fuel" theory, an uncertain reaction playing out in uncertain conditions, as compared to an optimized thermo-baric set-up, was put forth to account for the series of explosions, smoke, fire, and destruction reported in the lower parts of the buildings around the time of impact, and thereafter.
The "the magic jet fuel", however, was also just speculation, but it was adopted, retroactively, as part of the "official" account to explain anomalies, even though NIST concluded that the fuel was mostly aerosolized. Now you are diseminating it as fact, giving credence, back, to the hodge podge known as the official account.
NF, I don't understand where you are going with your latest commentary. It seems as if you are playing both sides against the middle.
Neu,
After my experiences at JREF, where I am constantly stalked and attacked by Beachnut and insulted by Pomeroo and others for being a "truther", and my experiences more recently at other truth movement sites where I have been banned and unfairly moderated for being a "debunker" or "disruptive" (read critical of pseudo-science), I am highly motivated to make sure moderation is fair and unbiased.
At least in the beginning, moderation may not be as timely as one might hope, but we will deal fairly with complaints, regardless of the stance of the poster. I will be personally monitoring our moderators to assure this.
/Greg
After my experiences at JREF, where I am constantly stalked and attacked by Beachnut and insulted by Pomeroo and others for being a "truther", and my experiences more recently at other truth movement sites where I have been banned and unfairly moderated for being a "debunker" or "disruptive" (read critical of pseudo-science), I am highly motivated to make sure moderation is fair and unbiased.
At least in the beginning, moderation may not be as timely as one might hope, but we will deal fairly with complaints, regardless of the stance of the poster. I will be personally monitoring our moderators to assure this.
/Greg
Zoktoberfest:
Well, you can't please all of the people all of the time...
But I must say that I'm getting this "whose side are you on?" thrown at me more and more and I suppose I should have seen it coming. All I can say is that I dont like the idea of "sides" in the 9/11 debate. The collapses of WTC 1, 2 & 7 were incredibly complex processes, so much so that I have recently suggested that we will probably never know exactly what happened. I say this mainly because of the paucity of physical evidence to support any particular theory....
However, when it comes to the fuel dispersion from the aircraft impacts on WTC 1 & 2 I look at the NIST Report and I see contradictions as to how NIST model the behavior of the fuel after the aircraft impacts .... so I have simply stated my concerns on this issue. I have in the past wondered just how violent the fuel-air explosions were and I have always felt that NIST underestimate the blast over-pressure.
So, Zoktoberfest, all I can say is this is probably a topic that deserves more discussion!
Well, you can't please all of the people all of the time...
But I must say that I'm getting this "whose side are you on?" thrown at me more and more and I suppose I should have seen it coming. All I can say is that I dont like the idea of "sides" in the 9/11 debate. The collapses of WTC 1, 2 & 7 were incredibly complex processes, so much so that I have recently suggested that we will probably never know exactly what happened. I say this mainly because of the paucity of physical evidence to support any particular theory....
However, when it comes to the fuel dispersion from the aircraft impacts on WTC 1 & 2 I look at the NIST Report and I see contradictions as to how NIST model the behavior of the fuel after the aircraft impacts .... so I have simply stated my concerns on this issue. I have in the past wondered just how violent the fuel-air explosions were and I have always felt that NIST underestimate the blast over-pressure.
So, Zoktoberfest, all I can say is this is probably a topic that deserves more discussion!
i have taken the sherlock approach from the word go(although, admittedly having the opposite forgone conclusion of NF).
that meaning, the old, " .......however improbable must be the truth". so, no matter how much planning and exotic weaponry was used, it was definitely used. be it nukes, thermobarics, space guns, tesla resonators, plain old RDX, nano-thermate or giant invisible iron worms, it definitely was not a natural collapse.
i do recall more than one witness describe "sparkling" before the explosions that brought down the towers. that sounds like thermobarics. thermobarics and spray on "fire-proofing" ammonium percolate (thank you NF) or some such combination would be one way to go.
the massive propaganda campaign and willful media ignorance is more evidence. the destruction of evidence in itself was criminal.
so, zoktoberfest, although i do suspect NF as being a skillful train derailer, i myself am guilty of the exact same thing, and i know my motivations are purely samaritan. i suspect NF may be the same, despite my honest 'king's men' comment.
it IS a complicated issue with a HUGE incredulity factor for either side of the story. "they" made sure of that. "they" also make sure no one with credulity has a voice. hence the banning, media blackouts, ridicule, firings and plain old murder. hence, they can put pictures of it on money, thousands of people can be in on it, rumsfeld can repeat 'missiles' over and over', bush can say he 'saw the first plane' over and over, 'the BBC can be psychic about WTC7's collapse, a rap band can have a precognitive album cover, anthrax terror can be spun into non-existance, etc, etc, etc.
i always thought they timed explosions to open a hole so the plane could enter nicely, whereas, now, i am starting to believe the TV fakery thing.
yes, it is HIGHLY, HIGHLY unlikely that that would be the plan, but, my dataset has always rejected a paper-thin aluminum plane slicing up a 500, 000 ton steel building without so much as a single buckle along the fuselage, and that's what we saw.
suspended disbelief is the path to clarity, i think. despite what the debunker's believe, i have processed all of their arguments and they do not add up. even NF is always looking for more energy sources, which indicates that there is not enough PE in the official story for NF's taste.
anyway, the total police state is here(the true goal of 911), so why don't we just sit in our cells and watch the world burn.
that meaning, the old, " .......however improbable must be the truth". so, no matter how much planning and exotic weaponry was used, it was definitely used. be it nukes, thermobarics, space guns, tesla resonators, plain old RDX, nano-thermate or giant invisible iron worms, it definitely was not a natural collapse.
i do recall more than one witness describe "sparkling" before the explosions that brought down the towers. that sounds like thermobarics. thermobarics and spray on "fire-proofing" ammonium percolate (thank you NF) or some such combination would be one way to go.
the massive propaganda campaign and willful media ignorance is more evidence. the destruction of evidence in itself was criminal.
so, zoktoberfest, although i do suspect NF as being a skillful train derailer, i myself am guilty of the exact same thing, and i know my motivations are purely samaritan. i suspect NF may be the same, despite my honest 'king's men' comment.
it IS a complicated issue with a HUGE incredulity factor for either side of the story. "they" made sure of that. "they" also make sure no one with credulity has a voice. hence the banning, media blackouts, ridicule, firings and plain old murder. hence, they can put pictures of it on money, thousands of people can be in on it, rumsfeld can repeat 'missiles' over and over', bush can say he 'saw the first plane' over and over, 'the BBC can be psychic about WTC7's collapse, a rap band can have a precognitive album cover, anthrax terror can be spun into non-existance, etc, etc, etc.
i always thought they timed explosions to open a hole so the plane could enter nicely, whereas, now, i am starting to believe the TV fakery thing.
yes, it is HIGHLY, HIGHLY unlikely that that would be the plan, but, my dataset has always rejected a paper-thin aluminum plane slicing up a 500, 000 ton steel building without so much as a single buckle along the fuselage, and that's what we saw.
suspended disbelief is the path to clarity, i think. despite what the debunker's believe, i have processed all of their arguments and they do not add up. even NF is always looking for more energy sources, which indicates that there is not enough PE in the official story for NF's taste.
anyway, the total police state is here(the true goal of 911), so why don't we just sit in our cells and watch the world burn.
QUOTE (Grumpy+Jul 5 2008, 04:05 PM)
Max Photon
Who said they did???
The first responders were interested more in rescue of survivors, not forensic investigations. Once cleared of the dangers of further explosions the why was the last thing on their minds, they worried about that afterward.
Thanks Grumpy! You really cleared something up for me.
I had always heard the "first responders/no explosives" line of thinking used over at JREF to argue that explosives - and hence CD (because JREFers can never conceive of any demolition mode other than explosives) - were definitively ruled out by the first responders/investigators.
And, to continue the JREF line of thinking, because explosives were ruled out - and because no other demolition mode exists (sic) - the structural steel was no longer evidence, and could be destroyed.
This is the basis of the JREF "no evidence was destroyed" argument.
Max
P.S. You might consider, as an alternative name,
PHYSOGR
Who said they did???
The first responders were interested more in rescue of survivors, not forensic investigations. Once cleared of the dangers of further explosions the why was the last thing on their minds, they worried about that afterward.
Thanks Grumpy! You really cleared something up for me.
I had always heard the "first responders/no explosives" line of thinking used over at JREF to argue that explosives - and hence CD (because JREFers can never conceive of any demolition mode other than explosives) - were definitively ruled out by the first responders/investigators.
And, to continue the JREF line of thinking, because explosives were ruled out - and because no other demolition mode exists (sic) - the structural steel was no longer evidence, and could be destroyed.
This is the basis of the JREF "no evidence was destroyed" argument.
Max
P.S. You might consider, as an alternative name,
PHYSOGR
NEU-FONZE --- I am sure we will never fully understand all aspects of such complex events.
By the way, in which tower is there reliable evidence of 'jet fuel pouring down elevator shafts'?
By the way, in which tower is there reliable evidence of 'jet fuel pouring down elevator shafts'?
DBB:
WTC1 for sure!
See NIST NCSTAR 1-5A, Chapter 6, page 80
However, NIST hint at something similar for WTC 2......
See NCSTAR 1-5A, Chapter 7, page 124, which mentions Grumpy's "raining" fuel.
WTC1 for sure!
See NIST NCSTAR 1-5A, Chapter 6, page 80
However, NIST hint at something similar for WTC 2......
See NCSTAR 1-5A, Chapter 7, page 124, which mentions Grumpy's "raining" fuel.
QUOTE (NEU-FONZE+Jul 6 2008, 12:36 PM)
WTC1 for sure!
I'm just wondering if the 'jet fuel' observed was not actually another liquid. Or maybe water with a jet fuel mist around it?
Up until you posted about how in such situations fuel always atomizes into a spray, I had accepted the 'flowing jet fuel' story. Now I am thinking it was something else and the reporter didn't recognize what it was, calling it 'jet fuel'.
I'm just wondering if the 'jet fuel' observed was not actually another liquid. Or maybe water with a jet fuel mist around it?
Up until you posted about how in such situations fuel always atomizes into a spray, I had accepted the 'flowing jet fuel' story. Now I am thinking it was something else and the reporter didn't recognize what it was, calling it 'jet fuel'.
QUOTE (David B. Benson+Jul 6 2008, 07:47 PM)
I'm just wondering if the 'jet fuel' observed was not actually another liquid. Or maybe water with a jet fuel mist around it?
Up until you posted about how in such situations fuel always atomizes into a spray, I had accepted the 'flowing jet fuel' story. Now I am thinking it was something else and the reporter didn't recognize what it was, calling it 'jet fuel'.
Dusting Off the Oldies, with Max Photon
David, (by the way, the title isn't referring to you)
One speculative hypothesis I threw out there - (you're going to laugh) - was that the jets were deliberately crashed into UPS rooms that had "batteries" filled not with lead and acid, but with iron and saltwater. The UPS were in fact iron oxide or rust generators.
The jets' aluminum skin shattered. The containers with iron oxide and water shattered. Extreme turbulence mixed the components. Natural thermite sparks ignited a broader thermite reaction, which, in the presence of water, created an aluminum-water reaction, in which water dissociates, and the hydrogen explodes. The burning of the hydrogen created water vapor, which condensed on dust, and dropped out as rain.
Max
Up until you posted about how in such situations fuel always atomizes into a spray, I had accepted the 'flowing jet fuel' story. Now I am thinking it was something else and the reporter didn't recognize what it was, calling it 'jet fuel'.
Dusting Off the Oldies, with Max Photon
David, (by the way, the title isn't referring to you)
One speculative hypothesis I threw out there - (you're going to laugh) - was that the jets were deliberately crashed into UPS rooms that had "batteries" filled not with lead and acid, but with iron and saltwater. The UPS were in fact iron oxide or rust generators.
The jets' aluminum skin shattered. The containers with iron oxide and water shattered. Extreme turbulence mixed the components. Natural thermite sparks ignited a broader thermite reaction, which, in the presence of water, created an aluminum-water reaction, in which water dissociates, and the hydrogen explodes. The burning of the hydrogen created water vapor, which condensed on dust, and dropped out as rain.
Max
QUOTE (Max Photon+Jul 6 2008, 02:03 PM)
Anyway, only works for WTC 2, and maybe not even there.
NEU-FONZE
An aerosol of fuel that impacts a surface CONDENSES on that surface.
Given the huge amount of fuel and the multiple condensing surfaces it does not seem out of the question that fuel DID flow as a liquid, as well as a vapor. If the mist is thick enough it condenses in mid air. If the overpressure of the fireball(A conflagration, not a detonation) travels down a shaft with a closed end(elevator shaft) and bounces off the closed end it can become thermobaric with a supersonic combustion. This could be the cause of the explosions that blew out the elevators. A reporter saw fireballs traveling up and down the elevator shafts and fuel could be smelled in the lobby.
There is nothing magic here.
Grumpy
An aerosol of fuel that impacts a surface CONDENSES on that surface.
Given the huge amount of fuel and the multiple condensing surfaces it does not seem out of the question that fuel DID flow as a liquid, as well as a vapor. If the mist is thick enough it condenses in mid air. If the overpressure of the fireball(A conflagration, not a detonation) travels down a shaft with a closed end(elevator shaft) and bounces off the closed end it can become thermobaric with a supersonic combustion. This could be the cause of the explosions that blew out the elevators. A reporter saw fireballs traveling up and down the elevator shafts and fuel could be smelled in the lobby.
There is nothing magic here.
Grumpy
IF there was residual fuel, and IF it went here, and IF it did this, and IF it then went there, and IF it then did that, and...
Whole lotta' IFin' goin' on.
...and IF the fuel was sufficient, and IF it didn't find all the other available gravity portals (not leading to the basement), and IF the fuel did find that express elevator to the basement, and IF it somehow encountered a dispersion mechanism, and IF the fuel began to aerosolize, and IF the ignition was delayed long enough to develop proper cloud sufficiency, and...
http://splodetv.com/fuel-air-explosion
This ones for you Grumpy
I got a black "magic jet fuel"
I got a black "magic jet fuel"
Yes, I got a Black "magic jet fuel"
It's got me so blind I can't see;
But it's a black "magic jet fuel" and
it's trying to make a devil out of me.
Whole lotta' IFin' goin' on.
...and IF the fuel was sufficient, and IF it didn't find all the other available gravity portals (not leading to the basement), and IF the fuel did find that express elevator to the basement, and IF it somehow encountered a dispersion mechanism, and IF the fuel began to aerosolize, and IF the ignition was delayed long enough to develop proper cloud sufficiency, and...
http://splodetv.com/fuel-air-explosion
This ones for you Grumpy
I got a black "magic jet fuel"
I got a black "magic jet fuel"
Yes, I got a Black "magic jet fuel"
It's got me so blind I can't see;
But it's a black "magic jet fuel" and
it's trying to make a devil out of me.
zoktoberfest
...and that is why NIST left out any speculation about it. Too many unknown(but possible)scenarios. By the way, the fuel was aerosolized ON IMPACT, only to then "wet" and condense on surfaces, becoming fluid again.
...and that is why NIST left out any speculation about it. Too many unknown(but possible)scenarios. By the way, the fuel was aerosolized ON IMPACT, only to then "wet" and condense on surfaces, becoming fluid again.
I got a black "magic jet fuel"
I got a black "magic jet fuel"
Yes, I got a Black "magic jet fuel"
It's got me so blind I can't see;
But it's a black "magic jet fuel" and
it's trying to make a devil out of me.
Just what part of gravity and a fluid flowing downhill(through every crack and crevice, INCLUDING ELEVATOR SHAFTS) is it you consider to be magic???
Surely you are not as stupid as your post makes you appear!!!
Grumpy
http://i37.tinypic.com/2e38h2q.jpg
This seems to provide a less extraordinary explanation for a particular issue raised in the video. Not saying it is this or not that, but it needs consideration.
it's the 'nose out' that bothers me. i know compression can deceive.
nice work, as always. it should be standard prerquisute learning for 'no planers'. (which i am undecided on, but lean towards TV fakery).
on another note, check this out, if you haven't seen it already.
http://i1.tinypic.com/sgn12g.gif
which is two adjacent frames from this video:
abc collapse video
i feel i've illustrated that explosions progressed down the side of the building faster than freefalling debris outside the building.
what do you think?
QUOTE
IF there was residual fuel, and IF it went here, and IF it did this, and IF it then went there, and IF it then did that, and...
Whole lotta' IFin' goin' on.
...and IF the fuel was sufficient, and IF it didn't find all the other available gravity portals (not leading to the basement), and IF the fuel did find that express elevator to the basement, and IF it somehow encountered a dispersion mechanism, and IF the fuel began to aerosolize, and IF the ignition was delayed long enough to develop proper cloud sufficiency, and...
Whole lotta' IFin' goin' on.
...and IF the fuel was sufficient, and IF it didn't find all the other available gravity portals (not leading to the basement), and IF the fuel did find that express elevator to the basement, and IF it somehow encountered a dispersion mechanism, and IF the fuel began to aerosolize, and IF the ignition was delayed long enough to develop proper cloud sufficiency, and...
...and that is why NIST left out any speculation about it. Too many unknown(but possible)scenarios. By the way, the fuel was aerosolized ON IMPACT, only to then "wet" and condense on surfaces, becoming fluid again.
QUOTE (->
| QUOTE |
| IF there was residual fuel, and IF it went here, and IF it did this, and IF it then went there, and IF it then did that, and... Whole lotta' IFin' goin' on. ...and IF the fuel was sufficient, and IF it didn't find all the other available gravity portals (not leading to the basement), and IF the fuel did find that express elevator to the basement, and IF it somehow encountered a dispersion mechanism, and IF the fuel began to aerosolize, and IF the ignition was delayed long enough to develop proper cloud sufficiency, and... |
...and that is why NIST left out any speculation about it. Too many unknown(but possible)scenarios. By the way, the fuel was aerosolized ON IMPACT, only to then "wet" and condense on surfaces, becoming fluid again.
I got a black "magic jet fuel"
I got a black "magic jet fuel"
Yes, I got a Black "magic jet fuel"
It's got me so blind I can't see;
But it's a black "magic jet fuel" and
it's trying to make a devil out of me.
Just what part of gravity and a fluid flowing downhill(through every crack and crevice, INCLUDING ELEVATOR SHAFTS) is it you consider to be magic???
Surely you are not as stupid as your post makes you appear!!!
Grumpy
newton --- Commercial airplanes are designed to hold together whilst flying through a thunderstorm. So there is no surprise that the impacting 767s appeared to simply disappear inside the towers.
QUOTE (David B. Benson+Jul 7 2008, 05:39 PM)
newton --- Commercial airplanes are designed to hold together whilst flying through a thunderstorm. So there is no surprise that the impacting 767s appeared to simply disappear inside the towers.
Just like the Sandia test, it really holded together...
Just like the Sandia test, it really holded together...
QUOTE (David B. Benson+Jul 7 2008, 05:39 PM)
newton --- Commercial airplanes are designed to hold together whilst flying through a thunderstorm. So there is no surprise that the impacting 767s appeared to simply disappear inside the towers.
you equate a 100 mph wind to a structural steel lattice?
i think i'll take the word of the guy who invented the 'shaker' over yours, no offense(especially since my science agrees....thin aluminum shells cannot 'butter' into massive steel buildings without crumpling, twisting, snapping, shredding....). he says, 'no way. completely impossible'.
too bad you can't watch the movie i linked to. it shows dozens of plane crashes and damage from things like birds. as he pointed out, passenger planes have warnings written on the wings not to walk on them. they're almost paper thin, and just walking on the wing can make the plane unfit for flight. there is a big difference in density between a gas and a solid, david.
anyone see spiderman 3 where the tower crane rips up the building? no surprise, there, either. it was also fake "hollywood physics".
you equate a 100 mph wind to a structural steel lattice?
i think i'll take the word of the guy who invented the 'shaker' over yours, no offense(especially since my science agrees....thin aluminum shells cannot 'butter' into massive steel buildings without crumpling, twisting, snapping, shredding....). he says, 'no way. completely impossible'.
too bad you can't watch the movie i linked to. it shows dozens of plane crashes and damage from things like birds. as he pointed out, passenger planes have warnings written on the wings not to walk on them. they're almost paper thin, and just walking on the wing can make the plane unfit for flight. there is a big difference in density between a gas and a solid, david.
anyone see spiderman 3 where the tower crane rips up the building? no surprise, there, either. it was also fake "hollywood physics".
newton --- You did see those Sandia tests, did you not?
Highly similar response.
No, airplanes are not built like aluminum cans...
Highly similar response.
No, airplanes are not built like aluminum cans...
QUOTE (David B. Benson+Jul 8 2008, 12:20 AM)
newton --- You did see those Sandia tests, did you not?
Highly similar response.
No, airplanes are not built like aluminum cans...
yes. the plane atomised on impact with only the wingtips surviving.
that's more like what should be expected. also, the 'powdered' plane bits all bounced back. even nist's sim shows debris being deflected back.
in the 911 deception, there is no blowback.
they are aluminum cans. otherwise, they wouldn't fly, because they would be too heavy.
Highly similar response.
No, airplanes are not built like aluminum cans...
yes. the plane atomised on impact with only the wingtips surviving.
that's more like what should be expected. also, the 'powdered' plane bits all bounced back. even nist's sim shows debris being deflected back.
in the 911 deception, there is no blowback.
they are aluminum cans. otherwise, they wouldn't fly, because they would be too heavy.
I found this fire fighter's account particularly compelling. He and his crew were ascending B stairway in the North Tower, when the South Tower was hit. They would begin a frantic retreat, helping those along the way, when it fell.
I came to realize, that my understanding of the conditions in the lower levels of the North Tower, prior to collapse, were incomplete, to say the least. Based on this reading, I realize the need to consider retracting some opinions, based on ignorance, recently extended toward NEU FONZE and Grumpy. Sorry guys, take me to task, if you must. You both noted the same discrepancy between what NIST had published and what the eye witness's reported. This account reinforces that discrepancy, while capturing a disturbing exodus approaching oblivion.
Firefighter Peter Blaich
Ladder 123 - 2 years
(was at Engine 9 on 9/11)
(Excepts)
"We started going up the B stairway. As we got to the third floor of the B stairway, we forced open an elevator door which was burnt on all three sides. The only thing that was remaining was the hoistway door. And inside the elevator were about I didnt recognize them initially, but a guy from 1 Truck said oh my God, those are people. They were pretty incinerated. And I remember the overpowering smell of kerosene. Thats when Lieutenant Foti said oh, thats the jet fuel. I remember it smelled like if youre camping and you drop a kerosene lamp."
"Thats the first thing that got me. That and in front of one of the big elevator banks in the lobby was a desk and I definitely made out one of the corpses to be a security guard because he had a security label on his jacket. Im assuming that maybe he was at a table still in a chair and almost completely incinerated, charred all over his body, definitely dead. And you could make out like a security tag on his jacket. And I remember seeing the table was melted, but he was still fused in the chair and that elevator bank was melted, so I imagine the jet fuel must have blown right down the elevator shaft and I guess caught the security guard at a table, I guess at some type of checkpoint."
"We figured by the time we got to the fifth or sixth floor, thats when the south tower was hit. I had no idea the south tower was hit, and I dont think that Chief Jonas Captain Jonas at the time or Lieutenant Foti knew at that point either. I remember the whole north tower literally vibrated. The only way I can explain it is if you were at the edge of a subway platform and the train was coming in, you felt that wind and the sound, but with an added effect like the floor vibrated. Everybody just cringed and really was not sure what was going on. I just assumed that it was something above us. I had no idea that the south tower was hit."
http://www.firehouse.com/terrorist/911/mag.../gz/blaich.html
I came to realize, that my understanding of the conditions in the lower levels of the North Tower, prior to collapse, were incomplete, to say the least. Based on this reading, I realize the need to consider retracting some opinions, based on ignorance, recently extended toward NEU FONZE and Grumpy. Sorry guys, take me to task, if you must. You both noted the same discrepancy between what NIST had published and what the eye witness's reported. This account reinforces that discrepancy, while capturing a disturbing exodus approaching oblivion.
Firefighter Peter Blaich
Ladder 123 - 2 years
(was at Engine 9 on 9/11)
(Excepts)
"We started going up the B stairway. As we got to the third floor of the B stairway, we forced open an elevator door which was burnt on all three sides. The only thing that was remaining was the hoistway door. And inside the elevator were about I didnt recognize them initially, but a guy from 1 Truck said oh my God, those are people. They were pretty incinerated. And I remember the overpowering smell of kerosene. Thats when Lieutenant Foti said oh, thats the jet fuel. I remember it smelled like if youre camping and you drop a kerosene lamp."
"Thats the first thing that got me. That and in front of one of the big elevator banks in the lobby was a desk and I definitely made out one of the corpses to be a security guard because he had a security label on his jacket. Im assuming that maybe he was at a table still in a chair and almost completely incinerated, charred all over his body, definitely dead. And you could make out like a security tag on his jacket. And I remember seeing the table was melted, but he was still fused in the chair and that elevator bank was melted, so I imagine the jet fuel must have blown right down the elevator shaft and I guess caught the security guard at a table, I guess at some type of checkpoint."
"We figured by the time we got to the fifth or sixth floor, thats when the south tower was hit. I had no idea the south tower was hit, and I dont think that Chief Jonas Captain Jonas at the time or Lieutenant Foti knew at that point either. I remember the whole north tower literally vibrated. The only way I can explain it is if you were at the edge of a subway platform and the train was coming in, you felt that wind and the sound, but with an added effect like the floor vibrated. Everybody just cringed and really was not sure what was going on. I just assumed that it was something above us. I had no idea that the south tower was hit."
http://www.firehouse.com/terrorist/911/mag.../gz/blaich.html
While there are many issues I question regarding 9/11, the kerosene exploding in the shafts hypothesis has never surprised me. Has anyone ever built a "polish canon"? When I was a kid we used to take five or six pop cans (they used to be more substantial than they are today), and duct tape them together to make a canon that would shoot tennis balls. Three drops of lighter fluid, would shoot a tennis ball a hundred feet in the air. Of course we weren't satisfied so we experimented with ethanol and methanol too. Methanol worked so good that the tennis ball went so high we couldn't even see it! I never had the guts (or maybe it was good sense) to try gasoline or diesel fuel.
Newton,
You should look into the impact issues a bit more. So far, I have only seen the "sliced steel like butter" argument from laymen. The concept of momentum transfer is not particularly intuitive but most (if not all) engineers and physicists understand it. If you don't trust these guys, ask some truth movement engineer or physicist like Tony Szamboti, Gordon Ross or Greg Jenkins.
Have you read the article by Wierzbicki? The basic concepts are correct but the conclusions are somewhat muddled in terms of the amount of damage to the core.
You should look into the impact issues a bit more. So far, I have only seen the "sliced steel like butter" argument from laymen. The concept of momentum transfer is not particularly intuitive but most (if not all) engineers and physicists understand it. If you don't trust these guys, ask some truth movement engineer or physicist like Tony Szamboti, Gordon Ross or Greg Jenkins.
Have you read the article by Wierzbicki? The basic concepts are correct but the conclusions are somewhat muddled in terms of the amount of damage to the core.
QUOTE (Hambone+Jul 8 2008, 08:07 AM)
Newton,
You should look into the impact issues a bit more. So far, I have only seen the "sliced steel like butter" argument from laymen. The concept of momentum transfer is not particularly intuitive but most (if not all) engineers and physicists understand it. If you don't trust these guys, ask some truth movement engineer or physicist like Tony Szamboti, Gordon Ross or Greg Jenkins.
Have you read the article by Wierzbicki? The basic concepts are correct but the conclusions are somewhat muddled in terms of the amount of damage to the core.
thank you, hambone .
warner bros. impact
watch the sandia test, and then that impact. there is no shredded aluminum cloud of debris, and no gaping hole created in realtime. the hole we see after the smoke is cleared should be evident on impact. it is fake. a CGI overlay on top of timed explosions coming from inside the towers.
my brother is an aircraft 'guy'. he assured me that the wing spars(3 per wing, IIRC) were quite strong, and i believe they could have done some serious damage to the towers(if there was a plane). a 'roadrunner' cutout of a plane is unrealistic, though. the nose of a plane is really weak.
that's why i find arguments like this, nose out, highly compelling. what can happen and what did happen are different things.
there is no way a fireball did all the damage described in the basement. people incinerated and the smell of kerosene is no proof of a fireball from an airplane. certainly, it would be part of the plan to include this 'evidence', since 'they' knew what they were faking.
i will check out tony and greg. gordon and i did battle against the beast together, here, on the original 'physics of 911' thread. gordon has a great head on his shoulders.
You should look into the impact issues a bit more. So far, I have only seen the "sliced steel like butter" argument from laymen. The concept of momentum transfer is not particularly intuitive but most (if not all) engineers and physicists understand it. If you don't trust these guys, ask some truth movement engineer or physicist like Tony Szamboti, Gordon Ross or Greg Jenkins.
Have you read the article by Wierzbicki? The basic concepts are correct but the conclusions are somewhat muddled in terms of the amount of damage to the core.
thank you, hambone .
warner bros. impact
watch the sandia test, and then that impact. there is no shredded aluminum cloud of debris, and no gaping hole created in realtime. the hole we see after the smoke is cleared should be evident on impact. it is fake. a CGI overlay on top of timed explosions coming from inside the towers.
my brother is an aircraft 'guy'. he assured me that the wing spars(3 per wing, IIRC) were quite strong, and i believe they could have done some serious damage to the towers(if there was a plane). a 'roadrunner' cutout of a plane is unrealistic, though. the nose of a plane is really weak.
that's why i find arguments like this, nose out, highly compelling. what can happen and what did happen are different things.
there is no way a fireball did all the damage described in the basement. people incinerated and the smell of kerosene is no proof of a fireball from an airplane. certainly, it would be part of the plan to include this 'evidence', since 'they' knew what they were faking.
i will check out tony and greg. gordon and i did battle against the beast together, here, on the original 'physics of 911' thread. gordon has a great head on his shoulders.
In the Sandia test, the aircraft impacted a very thick piece of concrete. At the towers, the exterior wall was built up out of relatively thin pieces of steel.
The average "skin thickness" of an aluminum alloy (2024 or 7075) fuselage is about 2 mm, and about 50 m^2 of Al aircraft surfaces impacted the WTC columns in each tower. This amounts to about 270 kg of Al striking the steel columns.
The impact energy absorbed by each aircraft was about 1000 MJ, of which about 1/4 would have been absorbed by the airframe. Hence we have an energy uptake by the aircraft's 270 kg of Al surfaces of about 250 MJ = 926 kJ/kg.
Now, because the heat capacity of Al is about 1 kJ/kg. deg C, we can expect the impacted Al to have melted on impact, since it was actually an Al-Zn-Mg-Cu alloy with a m.p ~ 500 deg C or lower.
So, upon impact into the Twin Towers, the aircraft's aluminum skin would first melt then, (because of the extreme shear forces), it would break up into many tiny droplets that would be injected into the fireball. This would greatly enhance the force of the fuel-air explosion in each tower, ..... something that was not considered by NIST.
The impact energy absorbed by each aircraft was about 1000 MJ, of which about 1/4 would have been absorbed by the airframe. Hence we have an energy uptake by the aircraft's 270 kg of Al surfaces of about 250 MJ = 926 kJ/kg.
Now, because the heat capacity of Al is about 1 kJ/kg. deg C, we can expect the impacted Al to have melted on impact, since it was actually an Al-Zn-Mg-Cu alloy with a m.p ~ 500 deg C or lower.
So, upon impact into the Twin Towers, the aircraft's aluminum skin would first melt then, (because of the extreme shear forces), it would break up into many tiny droplets that would be injected into the fireball. This would greatly enhance the force of the fuel-air explosion in each tower, ..... something that was not considered by NIST.
NEU-FONZE --- Nor Purdue?
Anyway, that would occur only until the 767 had punched trough the perimeter wall. The the trailing portions of the aircraft would just slide in, more-or-less intact?
NIST had to use the 'more severe' scenarios in order to obtain the more realistic scenario.
By the way, the leading edges of the 767s's wings were carbon composite fiber, so you may need to re-think what you have.
Anyway, that would occur only until the 767 had punched trough the perimeter wall. The the trailing portions of the aircraft would just slide in, more-or-less intact?
NIST had to use the 'more severe' scenarios in order to obtain the more realistic scenario.
By the way, the leading edges of the 767s's wings were carbon composite fiber, so you may need to re-think what you have.
QUOTE (newton+Jul 8 2008, 03:30 PM)
that's why i find arguments like this, nose out, highly compelling. what can happen and what did happen are different things.
Regarding the consequences of compression artifact, look at a portion of a frame captured from the video, where the plane nose is at the right:
http://i33.tinypic.com/4qhwo.jpg
Now, look a vector drawing made from three colors sampled off of the video frame:
http://i38.tinypic.com/wtyj9u.jpg
Zooming in on the place where the elongated ellipse overlaps the rectangle, it is apparent the tip of the ellipse is out of view behind the rectangle:
http://i34.tinypic.com/2945esz.jpg
Take the same crisp image and save it to jpeg with 'Quality=1' and this is what you get:
http://i34.tinypic.com/mb037m.jpg
Now the ellipse appears to penetrate or pass in front of the rectangle:
http://i37.tinypic.com/2e38h2q.jpg
This seems to provide a less extraordinary explanation for a particular issue raised in the video. Not saying it is this or not that, but it needs consideration.
Regarding the consequences of compression artifact, look at a portion of a frame captured from the video, where the plane nose is at the right:
http://i33.tinypic.com/4qhwo.jpg
Now, look a vector drawing made from three colors sampled off of the video frame:
http://i38.tinypic.com/wtyj9u.jpg
Zooming in on the place where the elongated ellipse overlaps the rectangle, it is apparent the tip of the ellipse is out of view behind the rectangle:
http://i34.tinypic.com/2945esz.jpg
Take the same crisp image and save it to jpeg with 'Quality=1' and this is what you get:
http://i34.tinypic.com/mb037m.jpg
Now the ellipse appears to penetrate or pass in front of the rectangle:
http://i37.tinypic.com/2e38h2q.jpg
This seems to provide a less extraordinary explanation for a particular issue raised in the video. Not saying it is this or not that, but it needs consideration.
QUOTE (OneWhiteEye+Jul 9 2008, 05:34 AM)
http://i37.tinypic.com/2e38h2q.jpg
This seems to provide a less extraordinary explanation for a particular issue raised in the video. Not saying it is this or not that, but it needs consideration.
it's the 'nose out' that bothers me. i know compression can deceive.
nice work, as always. it should be standard prerquisute learning for 'no planers'. (which i am undecided on, but lean towards TV fakery).
on another note, check this out, if you haven't seen it already.
http://i1.tinypic.com/sgn12g.gif
which is two adjacent frames from this video:
abc collapse video
i feel i've illustrated that explosions progressed down the side of the building faster than freefalling debris outside the building.
what do you think?
QUOTE (newton+Jul 9 2008, 06:32 AM)
it's the 'nose out' that bothers me.
The nose 'apparition' is visible in other videos, not so striking (or odd) as in this one, curious nonetheless. Examples a little later, too many files to dig through right now, the head swims. I believe einsteen's smear of the impact displayed it as well. I would not be able to predict that exit shape in advance from basic principles so any speculation involving hindsight is kinda funny. I don't know what it's supposed to look like.
Yes, I've seen it but not studied it. I need to study before answering definitively. There are a variety of possible explanations, I'll wager you've heard them all. Which if any apply here remains to be seen. Something dropping in front of the wall, coming out of the smoke at free fall from a higher starting point and earlier time? y = y0 + v0t + (at^2), must not forget the initial conditions. I know that corner survives quite a while after that, so I doubt it's any shearing, peel-off, buckling, fracturing, unzipping, or what have you that directly involves destroying that part of the perimeter.
Frames 92 and 93 seem to be the two in question. Just a little before that, some cladding goes whizzing past the rest of the destruction, just to put it in perspective.
I'll get back to you on it, for sure.
The nose 'apparition' is visible in other videos, not so striking (or odd) as in this one, curious nonetheless. Examples a little later, too many files to dig through right now, the head swims. I believe einsteen's smear of the impact displayed it as well. I would not be able to predict that exit shape in advance from basic principles so any speculation involving hindsight is kinda funny. I don't know what it's supposed to look like.
QUOTE
on another note, check this out, if you haven't seen it already.
http://i1.tinypic.com/sgn12g.gif
which is two adjacent frames from this video:
abc collapse video
i feel i've illustrated that explosions progressed down the side of the building faster than freefalling debris outside the building.
what do you think?
http://i1.tinypic.com/sgn12g.gif
which is two adjacent frames from this video:
abc collapse video
i feel i've illustrated that explosions progressed down the side of the building faster than freefalling debris outside the building.
what do you think?
Yes, I've seen it but not studied it. I need to study before answering definitively. There are a variety of possible explanations, I'll wager you've heard them all. Which if any apply here remains to be seen. Something dropping in front of the wall, coming out of the smoke at free fall from a higher starting point and earlier time? y = y0 + v0t + (at^2), must not forget the initial conditions. I know that corner survives quite a while after that, so I doubt it's any shearing, peel-off, buckling, fracturing, unzipping, or what have you that directly involves destroying that part of the perimeter.
Frames 92 and 93 seem to be the two in question. Just a little before that, some cladding goes whizzing past the rest of the destruction, just to put it in perspective.
I'll get back to you on it, for sure.
QUOTE (David B. Benson+Jul 9 2008, 01:49 AM)
NEU-FONZE --- Nor Purdue?
Anyway, that would occur only until the 767 had punched trough the perimeter wall. The the trailing portions of the aircraft would just slide in, more-or-less intact?
NIST had to use the 'more severe' scenarios in order to obtain the more realistic scenario.
By the way, the leading edges of the 767s's wings were carbon composite fiber, so you may need to re-think what you have.
DBB,
The leading edge of the wing given the high temperatures of the crash should react, as well, once the aluminum was reacting, the carbon fiber however would have had to have extremely high temperatures to break the graphite bonding,
However I achieved it in a combination even of graphite, aluminum and hydrocarbons on impact with steel.
The main reaction however is from the abraded skin reaction with the water created in hydrocarbon combustion and atmospheric air.
Also from possible storage tanks in the building this also causes more damage to the interior columns and reduces the need for fire proofing damage to cause collapse.
It also make other reactions highly likely, it occurred in every test, by the way I substituted graphite recurve bow limbs for the leading edge, I built a graphite bow in high school shop class and others since, so I had some lying around.
Also it should be noted that the fireball inside the building would have expanded do to hydrogen released from water when aluminum reacted with it in combustion, the nitrogen in the air even acts as a catalytic agent to extend and prolong the effect.
Not that anyone should actually listen to me on this I just did the experiments a few years ago.
Anyway, that would occur only until the 767 had punched trough the perimeter wall. The the trailing portions of the aircraft would just slide in, more-or-less intact?
NIST had to use the 'more severe' scenarios in order to obtain the more realistic scenario.
By the way, the leading edges of the 767s's wings were carbon composite fiber, so you may need to re-think what you have.
DBB,
The leading edge of the wing given the high temperatures of the crash should react, as well, once the aluminum was reacting, the carbon fiber however would have had to have extremely high temperatures to break the graphite bonding,
However I achieved it in a combination even of graphite, aluminum and hydrocarbons on impact with steel.
The main reaction however is from the abraded skin reaction with the water created in hydrocarbon combustion and atmospheric air.
Also from possible storage tanks in the building this also causes more damage to the interior columns and reduces the need for fire proofing damage to cause collapse.
It also make other reactions highly likely, it occurred in every test, by the way I substituted graphite recurve bow limbs for the leading edge, I built a graphite bow in high school shop class and others since, so I had some lying around.
Also it should be noted that the fireball inside the building would have expanded do to hydrogen released from water when aluminum reacted with it in combustion, the nitrogen in the air even acts as a catalytic agent to extend and prolong the effect.
Not that anyone should actually listen to me on this I just did the experiments a few years ago.
DBB/Chainsaw:
According to the information I have from various websites the leading edge of a Boeing 767 is aluminum. The UPPER panels of the leading edge are fiberglass, but these are horizontal in flight and would not take the brunt of an impact.
Composites ARE use on a 767 but for things like the ailerons, rudder, wind trailing edge, fairings, landing gear doors, tail horizontal stabilizers and the empennage.
The B-2 bomber has full composite wings but Boeing has not achieved this for a jetliner because the wings carry much greater loads on passenger aircraft.
According to the information I have from various websites the leading edge of a Boeing 767 is aluminum. The UPPER panels of the leading edge are fiberglass, but these are horizontal in flight and would not take the brunt of an impact.
Composites ARE use on a 767 but for things like the ailerons, rudder, wind trailing edge, fairings, landing gear doors, tail horizontal stabilizers and the empennage.
The B-2 bomber has full composite wings but Boeing has not achieved this for a jetliner because the wings carry much greater loads on passenger aircraft.
QUOTE (OneWhiteEye+Jul 4 2008, 08:34 PM)
Thank you. I added breakable fixed joints (connections) after that post, so now walls can be walls and not stacks. I hope the future will bring some interesting stuff.
That was done using the PhysX SDK (formerly AEGIA and now under NVIDIA). There's no application software, just a library and you write your own C++ code to create the scene, set the parameters and so forth. I'm also working with ChronoEngine, IBDS, TrueAxis and a couple of others as basic physics engines but the professional nature of PhysX justs makes it easier to use. The collection can be integrated into layers under a common implementation using Physics Abstraction Layer (all this stuff is free, by the way). These are game engines, for sure, and not industrial-strength FEM libraries, but I believe the higher quality engines can do a pretty decent job of modeling exemplar behavior of certain simple dynamical situations. You have to be aware of the limitations, intimately, and be very careful in your setup to avoid nonsense results... and take it for what it is: much better than any BS I could implement!
In fact, the solvers for PhysX and IBDS in particular are exceptional, and certainly rival ANY sort of simulator from a couple of decades ago. Yes, there are situations where you can get a stupefying amount of artifact but, for a lot of things (like pendulums, buckling, collsions of ensembles of objects, etc.) you can get the basic feel for the behavior of a system. My goal here is to characterize the behavior of idealized dynamic systems with many constituents of few types and simple structure.
Since these engines are developed for game purposes, the emphasis is on speed over accuracy and there are certain clever non-physical tricks to get stability and convergence that work for games but are utterly meaningless in the real world. I've found that avoiding the tricks and using small time steps and many iterations produces some pretty accurate results for well-conditioned problems. The simulation frame rate is quite slow (even with PhysX GPU and quad core CPU) but I just capture the OpenGL buffer into frames and make a movie. The main thrust however, will be examining overall dynamics and distribution of energies and momenta over time of various constituents and aggregates. I will use multiple engines on the same systems for comparison.
I need to understand stochastic quasi-fluid properties of medium size ensembles of structural components. In doing so, I may contruct models decidedly non-physical in superficial appearance. This is easier/cheaper than crushing tinkertoy models in my garage (yes, Arthur, I was kidding about that, but when it comes down physical validation of computer models, who knows).
That's quite impressive, and also interesting that you have managed to do this with tools made for game engines. I made a brief attempt sometime ago to generate some simple collapse models like this, but didn't think of going that route (and I don't think my limited programming skills would allow me to anyway!). I had a little crack at using LS-DYNA, which seemed best suited for this kind of dynamic FEA, but didn't get very far - basically lack of good documentation and time. But I was very interested in doing some simple collapse models of towers (upper block/lower block) - with no preconceived assumptions - to see what things looked like; and to see if the "floor by floor" models that the analytical models assume have any validity. So, I am glad that someone is doing something along those lines.
What I was impressed with in LS-DYNA was the number of materials and also boundary conditions you could impose out of the box. It may be a little tricky to do things like that in PhysX, but if you have found out how to do breakable joints than sounds like you figured it out.
Anyway, good luck!
That was done using the PhysX SDK (formerly AEGIA and now under NVIDIA). There's no application software, just a library and you write your own C++ code to create the scene, set the parameters and so forth. I'm also working with ChronoEngine, IBDS, TrueAxis and a couple of others as basic physics engines but the professional nature of PhysX justs makes it easier to use. The collection can be integrated into layers under a common implementation using Physics Abstraction Layer (all this stuff is free, by the way). These are game engines, for sure, and not industrial-strength FEM libraries, but I believe the higher quality engines can do a pretty decent job of modeling exemplar behavior of certain simple dynamical situations. You have to be aware of the limitations, intimately, and be very careful in your setup to avoid nonsense results... and take it for what it is: much better than any BS I could implement!
In fact, the solvers for PhysX and IBDS in particular are exceptional, and certainly rival ANY sort of simulator from a couple of decades ago. Yes, there are situations where you can get a stupefying amount of artifact but, for a lot of things (like pendulums, buckling, collsions of ensembles of objects, etc.) you can get the basic feel for the behavior of a system. My goal here is to characterize the behavior of idealized dynamic systems with many constituents of few types and simple structure.
Since these engines are developed for game purposes, the emphasis is on speed over accuracy and there are certain clever non-physical tricks to get stability and convergence that work for games but are utterly meaningless in the real world. I've found that avoiding the tricks and using small time steps and many iterations produces some pretty accurate results for well-conditioned problems. The simulation frame rate is quite slow (even with PhysX GPU and quad core CPU) but I just capture the OpenGL buffer into frames and make a movie. The main thrust however, will be examining overall dynamics and distribution of energies and momenta over time of various constituents and aggregates. I will use multiple engines on the same systems for comparison.
I need to understand stochastic quasi-fluid properties of medium size ensembles of structural components. In doing so, I may contruct models decidedly non-physical in superficial appearance. This is easier/cheaper than crushing tinkertoy models in my garage (yes, Arthur, I was kidding about that, but when it comes down physical validation of computer models, who knows).
That's quite impressive, and also interesting that you have managed to do this with tools made for game engines. I made a brief attempt sometime ago to generate some simple collapse models like this, but didn't think of going that route (and I don't think my limited programming skills would allow me to anyway!). I had a little crack at using LS-DYNA, which seemed best suited for this kind of dynamic FEA, but didn't get very far - basically lack of good documentation and time. But I was very interested in doing some simple collapse models of towers (upper block/lower block) - with no preconceived assumptions - to see what things looked like; and to see if the "floor by floor" models that the analytical models assume have any validity. So, I am glad that someone is doing something along those lines.
What I was impressed with in LS-DYNA was the number of materials and also boundary conditions you could impose out of the box. It may be a little tricky to do things like that in PhysX, but if you have found out how to do breakable joints than sounds like you figured it out.
Anyway, good luck!
QUOTE (NEU-FONZE+Jul 9 2008, 03:51 PM)
DBB/Chainsaw:
According to the information I have from various websites the leading edge of a Boeing 767 is aluminum. The UPPER panels of the leading edge are fiberglass, but these are horizontal in flight and would not take the brunt of an impact.
Composites ARE use on a 767 but for things like the ailerons, rudder, wind trailing edge, fairings, landing gear doors, tail horizontal stabilizers and the empennage.
The B-2 bomber has full composite wings but Boeing has not achieved this for a jetliner because the wings carry much greater loads on passenger aircraft.
Your correct, Neu Fonze, that means that there is sufficient aluminum to cause a magnified reaction in the fire ball, that is why explosives, or thermite, or AP. compounds can not survive the impact and fire balls.
Just as my tests have always shown, the fireball is more intense that NIST estimated, and hydrogen and a low pressure detonation like wave is produced that would transit the buildings structure so directly placed explosives would also be unlikely to survive.
http://oea.larc.nasa.gov/PAIS/Concept2Real...composites.html
I must point out that a limited amount of AP. would work, if it were used solely to produce a gas to compromise the fire proof coating or in very limited amounts.
However just injecting water inside the fire proofing would achieve the same goal.
According to the information I have from various websites the leading edge of a Boeing 767 is aluminum. The UPPER panels of the leading edge are fiberglass, but these are horizontal in flight and would not take the brunt of an impact.
Composites ARE use on a 767 but for things like the ailerons, rudder, wind trailing edge, fairings, landing gear doors, tail horizontal stabilizers and the empennage.
The B-2 bomber has full composite wings but Boeing has not achieved this for a jetliner because the wings carry much greater loads on passenger aircraft.
Your correct, Neu Fonze, that means that there is sufficient aluminum to cause a magnified reaction in the fire ball, that is why explosives, or thermite, or AP. compounds can not survive the impact and fire balls.
Just as my tests have always shown, the fireball is more intense that NIST estimated, and hydrogen and a low pressure detonation like wave is produced that would transit the buildings structure so directly placed explosives would also be unlikely to survive.
http://oea.larc.nasa.gov/PAIS/Concept2Real...composites.html
I must point out that a limited amount of AP. would work, if it were used solely to produce a gas to compromise the fire proof coating or in very limited amounts.
However just injecting water inside the fire proofing would achieve the same goal.
I stand corrected. Thanks, NEU-FONZE.
DBB:
You are most welcome!
Chainsaw:
Thanks for that excellent link about composites with the diagram of a 767. I believe a 767 has about 3000 pounds of composite materials which presumably would have burned in the WTC fires.
You are most welcome!
Chainsaw:
Thanks for that excellent link about composites with the diagram of a 767. I believe a 767 has about 3000 pounds of composite materials which presumably would have burned in the WTC fires.
QUOTE (NEU-FONZE+Jul 9 2008, 08:03 PM)
DBB:
You are most welcome!
Chainsaw:
Thanks for that excellent link about composites with the diagram of a 767. I believe a 767 has about 3000 pounds of composite materials which presumably would have burned in the WTC fires.
Your most welcome NEU, just hope it helps in your research.
You are most welcome!
Chainsaw:
Thanks for that excellent link about composites with the diagram of a 767. I believe a 767 has about 3000 pounds of composite materials which presumably would have burned in the WTC fires.
Your most welcome NEU, just hope it helps in your research.
Chainsaw:
I can't believe those goofballs over at JREF have started a thread trying to compile a list of all the elements that were present in the Twin Towers! Those gormless NISTIANS are trying to refute Jones, but are going about it entirely the wrong way!
I guess they are too dumb to realize that the interesting question is not what's in the WTC dust, nor even in the microspheres, but what's in the MAGNETIC fraction of the microspheres and how those elements are combined. They have apparently forgotten how Jones collected his microspheres,........
I would normally try to help them, but they went and banned me over there so now I watch (and laugh) from the sidelines...
I can't believe those goofballs over at JREF have started a thread trying to compile a list of all the elements that were present in the Twin Towers! Those gormless NISTIANS are trying to refute Jones, but are going about it entirely the wrong way!
I guess they are too dumb to realize that the interesting question is not what's in the WTC dust, nor even in the microspheres, but what's in the MAGNETIC fraction of the microspheres and how those elements are combined. They have apparently forgotten how Jones collected his microspheres,........
I would normally try to help them, but they went and banned me over there so now I watch (and laugh) from the sidelines...
QUOTE (NEU-FONZE+Jul 9 2008, 11:09 PM)
Chainsaw:
I can't believe those goofballs over at JREF have started a thread trying to compile a list of all the elements that were present in the Twin Towers! Those gormless NISTIANS are trying to refute Jones, but are going about it entirely the wrong way!
I guess they are too dumb to realize that the interesting question is not what's in the WTC dust, nor even in the microspheres, but what's in the MAGNETIC fraction of the microspheres and how those elements are combined. They have apparently forgotten how Jones collected his microspheres,........
I would normally try to help them, but they went and banned me over there so now I watch (and laugh) from the sidelines...
I know, I laughed too at that thread, JERFers are their own worst enemy.
I have the author of that thread on ignore, so I have decided not to reply to the thread.
I can't believe those goofballs over at JREF have started a thread trying to compile a list of all the elements that were present in the Twin Towers! Those gormless NISTIANS are trying to refute Jones, but are going about it entirely the wrong way!
I guess they are too dumb to realize that the interesting question is not what's in the WTC dust, nor even in the microspheres, but what's in the MAGNETIC fraction of the microspheres and how those elements are combined. They have apparently forgotten how Jones collected his microspheres,........
I would normally try to help them, but they went and banned me over there so now I watch (and laugh) from the sidelines...
I know, I laughed too at that thread, JERFers are their own worst enemy.
I have the author of that thread on ignore, so I have decided not to reply to the thread.
Bazant rebuttal to Gurley, Jones, and Suladzinski, submitted to ASCE Feb 2008:
http://www.civil.northwestern.edu/people/b...l_by_Bazant.pdf
http://www.civil.northwestern.edu/people/b...l_by_Bazant.pdf
QUOTE (metamars+Jul 10 2008, 01:26 AM)
Bazant rebuttal to Gurley, Jones, and Suladzinski, submitted to ASCE Feb 2008:
http://www.civil.northwestern.edu/people/b...l_by_Bazant.pdf
Thanks metamars for posting that, I found the link on other sites but it would not work for me.
If correct then the collapse began at the impact area, and as NEU said there was an intensification of the fireball by oxidizing aluminum, and hydrocarbons, that would I know also lead to hydrogen release, and even more intense pressure waves.
That would prevent any explosive or incendiary from surviving just as my early experiments showed years ago, CD, was and is a myth.
It also naturally increases the damage to the fire proofing and would probably increase the chance of entrapped gasses in the buildings in the fires.
I would like for others more knowledgeable than myself on the physics to comment however before I make further comment, I could be wrong, and freely admit it, but if collapse initiation began at the impact zone under those conditions the likely hood of explosives incendiaries surviving in the buildings to trigger the collapse is about as good as the abominable snow man vacationing on the surface of the sun and gaining weight from consuming fresh snow there.
http://www.civil.northwestern.edu/people/b...l_by_Bazant.pdf
Thanks metamars for posting that, I found the link on other sites but it would not work for me.
If correct then the collapse began at the impact area, and as NEU said there was an intensification of the fireball by oxidizing aluminum, and hydrocarbons, that would I know also lead to hydrogen release, and even more intense pressure waves.
That would prevent any explosive or incendiary from surviving just as my early experiments showed years ago, CD, was and is a myth.
It also naturally increases the damage to the fire proofing and would probably increase the chance of entrapped gasses in the buildings in the fires.
I would like for others more knowledgeable than myself on the physics to comment however before I make further comment, I could be wrong, and freely admit it, but if collapse initiation began at the impact zone under those conditions the likely hood of explosives incendiaries surviving in the buildings to trigger the collapse is about as good as the abominable snow man vacationing on the surface of the sun and gaining weight from consuming fresh snow there.
Re;
http://oea.larc.nasa.gov/PAIS/Concept2Real...composites.html
"In the continual quest for reduced weight, aircraft manufacturers began to introduce applications of nonmetallic materials, such as fiberglass-reinforced plastic composites."
According to the reference material provided by chainsaw, the "Radome" (nose cone) assembly of a 767 is of a (nonmetallic) composite material. On most of the impact footage, a pronouced flash before impact is noticeable. With the understanding that the component is relatively inert, non conducting material, doesn't that limit the possible (non conspiracy) explanations to just massive static discharge. I suppose the bifurcation of the AL fuselage and the composite insert could produce a dielectric effect, but I'm just guessing and allowing the benefit of the doubt . Why would aircraft designers allow for such a magnitude of charge to collect on the nose, under any conditions?
Warning: Entering Conspiracy Zone!
http://www.youtube.com/watch?v=oVH5jm06pJY&feature=related
"The Japan KC-767 Tanker, a military derivative of the proven 767-200 commercial airplane, was selected over its competitor, the Airbus A-310, in a direct competition in 2001."
http://www.globalsecurity.org/military/lib...29-boeing01.htm
This excerpt indicates that functional KC-767 (tanker) existed as early as 2001 or before (consider that all the bugs had to be out the same year, that takes time).
Imagine putting a loaded tanker into a rapid descent, while accelerating to maximum speed down to a low altitude; consider all that fuel sloshing around, changing hull pressure, and suddenly, extreme levels of static discharge doesn't seem so unlikely. Who knows if there were composite components on this model.
There was no real demonstrable explanation for the flashes (normal aircraft have discharge modules along the wing), just another 9/11 anomaly drifting into the background like the pods under the aircraft. There was clearly something visually evident, but again no explanation. Effective derision though: "pod people, ..."
http://www.youtube.com/watch?v=yNNCfFKDofY&feature=related
End Of Conspiracy Zone.
Cue: Grumpy
http://oea.larc.nasa.gov/PAIS/Concept2Real...composites.html
"In the continual quest for reduced weight, aircraft manufacturers began to introduce applications of nonmetallic materials, such as fiberglass-reinforced plastic composites."
According to the reference material provided by chainsaw, the "Radome" (nose cone) assembly of a 767 is of a (nonmetallic) composite material. On most of the impact footage, a pronouced flash before impact is noticeable. With the understanding that the component is relatively inert, non conducting material, doesn't that limit the possible (non conspiracy) explanations to just massive static discharge. I suppose the bifurcation of the AL fuselage and the composite insert could produce a dielectric effect, but I'm just guessing and allowing the benefit of the doubt . Why would aircraft designers allow for such a magnitude of charge to collect on the nose, under any conditions?
Warning: Entering Conspiracy Zone!
http://www.youtube.com/watch?v=oVH5jm06pJY&feature=related
"The Japan KC-767 Tanker, a military derivative of the proven 767-200 commercial airplane, was selected over its competitor, the Airbus A-310, in a direct competition in 2001."
http://www.globalsecurity.org/military/lib...29-boeing01.htm
This excerpt indicates that functional KC-767 (tanker) existed as early as 2001 or before (consider that all the bugs had to be out the same year, that takes time).
Imagine putting a loaded tanker into a rapid descent, while accelerating to maximum speed down to a low altitude; consider all that fuel sloshing around, changing hull pressure, and suddenly, extreme levels of static discharge doesn't seem so unlikely. Who knows if there were composite components on this model.
There was no real demonstrable explanation for the flashes (normal aircraft have discharge modules along the wing), just another 9/11 anomaly drifting into the background like the pods under the aircraft. There was clearly something visually evident, but again no explanation. Effective derision though: "pod people, ..."
http://www.youtube.com/watch?v=yNNCfFKDofY&feature=related
End Of Conspiracy Zone.
Cue: Grumpy
QUOTE (lozenge124+Jul 9 2008, 04:48 PM)
I made a brief attempt sometime ago to generate some simple collapse models like this, but didn't think of going that route (and I don't think my limited programming skills would allow me to anyway!). I had a little crack at using LS-DYNA, which seemed best suited for this kind of dynamic FEA, but didn't get very far - basically lack of good documentation and time.
LS-DYNA... I wish! But I don't have time to put in a life's work, either. Still have access to it?
I'm thinking about starting a thread over at Gregory's forum to cover crude simulations like this, being somewhat off-topic here. I'd be pleased if you'd have thoughts to offer on the subject.
I'm thinking about starting a thread over at Gregory's forum to cover crude simulations like this, being somewhat off-topic here. I'd be pleased if you'd have thoughts to offer on the subject.
What I was impressed with in LS-DYNA was the number of materials and also boundary conditions you could impose out of the box. It may be a little tricky to do things like that in PhysX, but if you have found out how to do breakable joints than sounds like you figured it out.
Unfortunately the physics engines don't approach that level of sophistication and I wish there was some middle ground. Some of the limitations of PhysX are already beginning to show. I'm a little disappointed in the behavior of the 'fixed' joints - they're supposed to be rigid but aren't. A few other things not so hot but I'm still happy overall, enough to have done hundreds of different runs just playing around, firing teapots at high velocity into towers. Guess I never got over playing with blocks.
LS-DYNA... I wish! But I don't have time to put in a life's work, either. Still have access to it?
QUOTE
But I was very interested in doing some simple collapse models of towers (upper block/lower block) - with no preconceived assumptions - to see what things looked like; and to see if the "floor by floor" models that the analytical models assume have any validity. So, I am glad that someone is doing something along those lines.
I'm thinking about starting a thread over at Gregory's forum to cover crude simulations like this, being somewhat off-topic here. I'd be pleased if you'd have thoughts to offer on the subject.
QUOTE (->
| QUOTE |
| But I was very interested in doing some simple collapse models of towers (upper block/lower block) - with no preconceived assumptions - to see what things looked like; and to see if the "floor by floor" models that the analytical models assume have any validity. So, I am glad that someone is doing something along those lines. |
I'm thinking about starting a thread over at Gregory's forum to cover crude simulations like this, being somewhat off-topic here. I'd be pleased if you'd have thoughts to offer on the subject.
What I was impressed with in LS-DYNA was the number of materials and also boundary conditions you could impose out of the box. It may be a little tricky to do things like that in PhysX, but if you have found out how to do breakable joints than sounds like you figured it out.
Unfortunately the physics engines don't approach that level of sophistication and I wish there was some middle ground. Some of the limitations of PhysX are already beginning to show. I'm a little disappointed in the behavior of the 'fixed' joints - they're supposed to be rigid but aren't. A few other things not so hot but I'm still happy overall, enough to have done hundreds of different runs just playing around, firing teapots at high velocity into towers. Guess I never got over playing with blocks.
QUOTE (metamars+Jul 10 2008, 01:26 AM)
Bazant rebuttal to Gurley, Jones, and Suladzinski, submitted to ASCE Feb 2008:
http://www.civil.northwestern.edu/people/b...l_by_Bazant.pdf
Very interesting, thank you. I just got to this:
Wow.
http://www.civil.northwestern.edu/people/b...l_by_Bazant.pdf
Very interesting, thank you. I just got to this:
QUOTE
It was hypothesized that the lateral bowing of perimeter columns was caused mainly by a horizontal pull from steel trusses sagging due to differential thermal expansion. However, this hypothesis is not credible. As simple calculations show, the temperature difference between the lower and upper flanges of a floor truss would have to exceed 1000C in order to produce a curvature that would shorten the span of a sagging floor truss by 52 in. (1.40 m). Such a temperature difference is inconceivable. The differential thermal expansion must have been only a secondary contributing factor, which created a small initial imperfection in the overloaded columns, to be later drastically magnified by creep buckling.
Wow.
QUOTE (zoktoberfest+Jul 10 2008, 03:11 AM)
There was no real demonstrable explanation for the flashes (normal aircraft have discharge modules along the wing)...
I always assumed discharge. From what NEU-FONZE said, could it be thermal?
I always assumed discharge. From what NEU-FONZE said, could it be thermal?
OneWhiteEye & Oktoberfest:
While the 767 "radome" was fiberglass, it looks like the rest of the aircraft's nose was Alclad aluminum, probably 2024-T3. Thus ignition by impact, with or without "thermite sparking", still looks like the best explanation of the flash seen in videos of Flight 175 striking WTC 2. However, I have always wondered why we dont see similar sparking when the wings hit the perimeter wall.
While the 767 "radome" was fiberglass, it looks like the rest of the aircraft's nose was Alclad aluminum, probably 2024-T3. Thus ignition by impact, with or without "thermite sparking", still looks like the best explanation of the flash seen in videos of Flight 175 striking WTC 2. However, I have always wondered why we dont see similar sparking when the wings hit the perimeter wall.
QUOTE (NEU-FONZE+Jul 10 2008, 10:52 AM)
OneWhiteEye & Oktoberfest:
While the 767 "radome" was fiberglass, it looks like the rest of the aircraft's nose was Alclad aluminum, probably 2024-T3. Thus ignition by impact, with or without "thermite sparking", still looks like the best explanation of the flash seen in videos of Flight 175 striking WTC 2. However, I have always wondered why we dont see similar sparking when the wings hit the perimeter wall.
Because the sparking on the wings is driven into the wings fuel tanks, where it is hidden by the wing surfaces.
The only reason you see it on the fuselage is because the fuselage hits nose first if you turned the fuselage on its side and slammed it with equal force against the building the crushing of the fuselage would hide the sparking as well.
The leading edge of the wing tends to crumple inward, and the upper and lower surfaces tend to fold into the fuel tanks, that causes an explosion said Fuel air blast will hide and obscure further sparking.
Remember the wing has an air foil shape it is not going to enter the building or bend in the same manor as the fuselage with a heavy structural bulkhead in the center reinforcing the tube structure. I should also point out while the radome is fiber glass the bulk head the radome is attached to is aluminum, as well as the mount for the radar under the Radome.
Parts of the radar are also aluminum, it does not take much aluminum to put on a very bright show.
While the 767 "radome" was fiberglass, it looks like the rest of the aircraft's nose was Alclad aluminum, probably 2024-T3. Thus ignition by impact, with or without "thermite sparking", still looks like the best explanation of the flash seen in videos of Flight 175 striking WTC 2. However, I have always wondered why we dont see similar sparking when the wings hit the perimeter wall.
Because the sparking on the wings is driven into the wings fuel tanks, where it is hidden by the wing surfaces.
The only reason you see it on the fuselage is because the fuselage hits nose first if you turned the fuselage on its side and slammed it with equal force against the building the crushing of the fuselage would hide the sparking as well.
The leading edge of the wing tends to crumple inward, and the upper and lower surfaces tend to fold into the fuel tanks, that causes an explosion said Fuel air blast will hide and obscure further sparking.
Remember the wing has an air foil shape it is not going to enter the building or bend in the same manor as the fuselage with a heavy structural bulkhead in the center reinforcing the tube structure. I should also point out while the radome is fiber glass the bulk head the radome is attached to is aluminum, as well as the mount for the radar under the Radome.
Parts of the radar are also aluminum, it does not take much aluminum to put on a very bright show.
Quote: Chainsaw
"[...] it does not take much aluminum (within the composite radome) to put on a very bright show."
Interesting reply.
So, are you are implying, that this level of discharge is within acceptable operational parameters?
Had these aircraft landed at their designated destinations (instead of ...), the ground personnel would have experienced "...a very bright show" (that could be seen, BTW, a 1000' away in bright daylight) when normally servicing the aircraft?
Of course, all service conduits provide a "1st touch" ground function, to discharge the ever present, nominal static, but it seems to me, that arcing of that magnitude would be a highly dangerous safety hazard near refueling facilities, not to mention for the worker. I'm not aware that ground crews are expected to discharge lightening bolts. Aircraft are designed to dissipate static to manageable levels.
"[...] it does not take much aluminum (within the composite radome) to put on a very bright show."
Interesting reply.
So, are you are implying, that this level of discharge is within acceptable operational parameters?
Had these aircraft landed at their designated destinations (instead of ...), the ground personnel would have experienced "...a very bright show" (that could be seen, BTW, a 1000' away in bright daylight) when normally servicing the aircraft?
Of course, all service conduits provide a "1st touch" ground function, to discharge the ever present, nominal static, but it seems to me, that arcing of that magnitude would be a highly dangerous safety hazard near refueling facilities, not to mention for the worker. I'm not aware that ground crews are expected to discharge lightening bolts. Aircraft are designed to dissipate static to manageable levels.
OneWhiteEye --- Various simplified, or toy, models are certainly within scope here.
QUOTE (OneWhiteEye+Jul 10 2008, 07:01 AM)
Very interesting, thank you. I just got to this:
Wow.
You're welcome, but I wonder what the heck Bazant is thinking? I have always assumed that only differential heating of columns might matter, not floor elements. Furthermore, I've also assumed that only differential heating of some columns compared to other columns (and not one side of a column as compared to it's other side) needs to be considered, absent any CD hypothesis.
I know this was discussed earlier; I think NEU-FONZE thought it up. My recollection is that he didn't even discuss floor elements, either. Is this correct?
Wow.
You're welcome, but I wonder what the heck Bazant is thinking? I have always assumed that only differential heating of columns might matter, not floor elements. Furthermore, I've also assumed that only differential heating of some columns compared to other columns (and not one side of a column as compared to it's other side) needs to be considered, absent any CD hypothesis.
I know this was discussed earlier; I think NEU-FONZE thought it up. My recollection is that he didn't even discuss floor elements, either. Is this correct?
QUOTE (zoktoberfest+Jul 10 2008, 06:32 PM)
Quote: Chainsaw
"[...] it does not take much aluminum (within the composite radome) to put on a very bright show."
Interesting reply.
So, are you are implying, that this level of discharge is within acceptable operational parameters?
Had these aircraft landed at their designated destinations (instead of ...), the ground personnel would have experienced "...a very bright show" (that could be seen, BTW, a 1000' away in bright daylight) when normally servicing the aircraft?
Of course, all service conduits provide a "1st touch" ground function, to discharge the ever present, nominal static, but it seems to me, that arcing of that magnitude would be a highly dangerous safety hazard near refueling facilities, not to mention for the worker. I'm not aware that ground crews are expected to discharge lightening bolts. Aircraft are designed to dissipate static to manageable levels.
Impact of aluminum into steel causes ignition of aluminum with oxygen and a light twice as bright as the surface of the sun.
It was not a static discharge as the radome is attached to the planes bulkhead on which the radar sits.
"[...] it does not take much aluminum (within the composite radome) to put on a very bright show."
Interesting reply.
So, are you are implying, that this level of discharge is within acceptable operational parameters?
Had these aircraft landed at their designated destinations (instead of ...), the ground personnel would have experienced "...a very bright show" (that could be seen, BTW, a 1000' away in bright daylight) when normally servicing the aircraft?
Of course, all service conduits provide a "1st touch" ground function, to discharge the ever present, nominal static, but it seems to me, that arcing of that magnitude would be a highly dangerous safety hazard near refueling facilities, not to mention for the worker. I'm not aware that ground crews are expected to discharge lightening bolts. Aircraft are designed to dissipate static to manageable levels.
Impact of aluminum into steel causes ignition of aluminum with oxygen and a light twice as bright as the surface of the sun.
It was not a static discharge as the radome is attached to the planes bulkhead on which the radar sits.
QUOTE (NEU-FONZE+Jul 10 2008, 10:52 AM)
OneWhiteEye & Oktoberfest:
While the 767 "radome" was fiberglass, it looks like the rest of the aircraft's nose was Alclad aluminum, probably 2024-T3. Thus ignition by impact, with or without "thermite sparking", still looks like the best explanation of the flash seen in videos of Flight 175 striking WTC 2.
I shall revise my thinking, then.
While the 767 "radome" was fiberglass, it looks like the rest of the aircraft's nose was Alclad aluminum, probably 2024-T3. Thus ignition by impact, with or without "thermite sparking", still looks like the best explanation of the flash seen in videos of Flight 175 striking WTC 2.
I shall revise my thinking, then.
QUOTE (David B. Benson+Jul 10 2008, 08:49 PM)
OneWhiteEye --- Various simplified, or toy, models are certainly within scope here.
OK. I was more into hiding it away to avoid ridicule. After reading Bazant's napkin, I felt so... stupid. Like a monkey with a toolbox. Grabbing a wrench and beating on the box for a while may be entertaining but not lead to a fuller understanding.
OK. I was more into hiding it away to avoid ridicule. After reading Bazant's napkin, I felt so... stupid. Like a monkey with a toolbox. Grabbing a wrench and beating on the box for a while may be entertaining but not lead to a fuller understanding.
QUOTE (metamars+Jul 11 2008, 01:52 AM)
You're welcome, but I wonder what the heck Bazant is thinking?
Strange idea -- "...lateral bowing of perimeter columns was caused mainly by a horizontal pull from steel trusses sagging due to differential thermal expansion."
It is.
Strange idea -- "...lateral bowing of perimeter columns was caused mainly by a horizontal pull from steel trusses sagging due to differential thermal expansion."
QUOTE
I know this was discussed earlier; I think NEU-FONZE thought it up. My recollection is that he didn't even discuss floor elements, either. Is this correct?
It is.
Quote (NEU FONZE)
"Thus ignition by impact, with or without "thermite sparking", still looks like the best explanation of the flash seen in videos of Flight 175 striking WTC 2."
Quote (Chainsaw)
"Impact of aluminum into steel causes ignition of aluminum with oxygen and a light twice as bright as the surface of the sun.
You (both) surely note the controversy here, as to whether the flash did or did not precede (radome) contact. Since we are both viewing the same videos (aren't we?) it appears that conclusions concerning proximity in relation to event, are being dictated by the nature of the event, not by the actual evidence, such that it is. The effect determining the cause
This recently linked video, that you either, didn't watch or have indifference to, examines shadow progression across the face of the North Tower impact and concludes flash before impact.
http://www.youtube.com/watch?v=yNNCfFKDofY&feature=related
This video suggests something altogether different, indicating laser like dots across the impact site well before impact, and yes the flash we are discussing is also present.
Note; pay attention when at 01:20 time code
http://www.youtube.com/watch?v=yNNCfFKDofY&feature=related
9/11 is some real slippery stuff, when you try to get a good grasp.
"Thus ignition by impact, with or without "thermite sparking", still looks like the best explanation of the flash seen in videos of Flight 175 striking WTC 2."
Quote (Chainsaw)
"Impact of aluminum into steel causes ignition of aluminum with oxygen and a light twice as bright as the surface of the sun.
You (both) surely note the controversy here, as to whether the flash did or did not precede (radome) contact. Since we are both viewing the same videos (aren't we?) it appears that conclusions concerning proximity in relation to event, are being dictated by the nature of the event, not by the actual evidence, such that it is. The effect determining the cause
This recently linked video, that you either, didn't watch or have indifference to, examines shadow progression across the face of the North Tower impact and concludes flash before impact.
http://www.youtube.com/watch?v=yNNCfFKDofY&feature=related
This video suggests something altogether different, indicating laser like dots across the impact site well before impact, and yes the flash we are discussing is also present.
Note; pay attention when at 01:20 time code
http://www.youtube.com/watch?v=yNNCfFKDofY&feature=related
9/11 is some real slippery stuff, when you try to get a good grasp.
(Corrected link)
This video suggests something altogether different, indicating laser dot scans across the site face well before impact, and yes the flash we are discussing is also present.
Note; pay attention when at 01:20 time code
http://clipmarks.com/clipmark/E435EB48-4A9...4-19A5E9DCA928/
This video suggests something altogether different, indicating laser dot scans across the site face well before impact, and yes the flash we are discussing is also present.
Note; pay attention when at 01:20 time code
http://clipmarks.com/clipmark/E435EB48-4A9...4-19A5E9DCA928/
QUOTE (zoktoberfest+Jul 11 2008, 05:49 PM)
... laser dot scans ...
Better not to make assumptions about what is seen, rather just explain what is seen.
The aircraft certainly would have a bow wave and what you see might be due to windows breaking just in front of the nose.
Better not to make assumptions about what is seen, rather just explain what is seen.
The aircraft certainly would have a bow wave and what you see might be due to windows breaking just in front of the nose.
There is also a video around in which the explanation seems to be a white piece of paper. Why would a plane need a laser to reach its target ? And if it is needed why would they use a frequency in the visible spectrum...
QUOTE (einsteen+Jul 12 2008, 12:00 PM)
... a white piece of paper..
I like that. 
I like that.
QUOTE (zoktoberfest+Jul 12 2008, 12:49 AM)
(Corrected link)
This video suggests something altogether different, indicating laser dot scans across the site face well before impact, and yes the flash we are discussing is also present.
Note; pay attention when at 01:20 time code
http://clipmarks.com/clipmark/E435EB48-4A9...4-19A5E9DCA928/
If you watch an extended copy of this video carefully, you will see that the white "laser dot" also appears to move across the building to the right in the foreground.
Conclusion: the white dot is a piece of fluttering debris that is well in front of both the tower and the foreground building.
This video suggests something altogether different, indicating laser dot scans across the site face well before impact, and yes the flash we are discussing is also present.
Note; pay attention when at 01:20 time code
http://clipmarks.com/clipmark/E435EB48-4A9...4-19A5E9DCA928/
If you watch an extended copy of this video carefully, you will see that the white "laser dot" also appears to move across the building to the right in the foreground.
Conclusion: the white dot is a piece of fluttering debris that is well in front of both the tower and the foreground building.
QUOTE (Max Photon+Jul 12 2008, 02:55 PM)
Conclusion: the white dot is a piece of fluttering debris that is well in front of both the tower and the foreground building.
Thank you.
Thank you.
"Conclusion: the white dot is a piece of fluttering debris that is well in front of both the tower and the foreground building."
I completely agree, case closed on the laser dots, that weren't.
The flash at/before impact, however, wasn't a piece of fluttering white debris. It was captured from many pespectives, including this one.
I completely agree, case closed on the laser dots, that weren't.
The flash at/before impact, however, wasn't a piece of fluttering white debris. It was captured from many pespectives, including this one.
QUOTE (zoktoberfest+Jul 12 2008, 03:43 PM)
The flash at/before impact, ...
chainsaw suggested violent chemistry. Somebody suggested static discharge.
I'll suggest electrical short.
chainsaw suggested violent chemistry. Somebody suggested static discharge.
I'll suggest electrical short.
QUOTE (David B. Benson+Jul 12 2008, 11:18 PM)
chainsaw suggested violent chemistry. Somebody suggested static discharge.
I'll suggest electrical short.
It could be an electrical short, but that would be unlikely, it could also be the aluminum of the buildings reacting to the impact of the fiberglass in a flash powder like oxidation reaction the building did have aluminum cladding you know.
Electrical shorts tend to have a blueish tint, and an arching nature about them, as I just found out to day while wiring a 220 motor to a 60 amp breaker.
Some one put the white tape on the wrong wire again.
It seems to have an aluminum oxidation tint to it.
User posted image: User posted image
I'll suggest electrical short.
It could be an electrical short, but that would be unlikely, it could also be the aluminum of the buildings reacting to the impact of the fiberglass in a flash powder like oxidation reaction the building did have aluminum cladding you know.
Electrical shorts tend to have a blueish tint, and an arching nature about them, as I just found out to day while wiring a 220 motor to a 60 amp breaker.
Some one put the white tape on the wrong wire again.
It seems to have an aluminum oxidation tint to it.
User posted image: User posted image
QUOTE (Chainsaw,+Jul 12 2008, 05:04 PM)
... it could also be the aluminum of the buildings reacting to the impact of the fiberglass in a flash powder like oxidation reaction ...
Something like this seems likely.
Something like this seems likely.
QUOTE (David B. Benson+Jul 13 2008, 12:25 AM)
Something like this seems likely.
Especially since the special alloy in question would be even more reactive than the planes aluminum, it was designed to be extra shinny, and I believe it was designed by Alcoa Aluminum specifically for the buildings.
http://www.alcoa.com/global/en/news/news_d...1&newsYear=2003
Especially since the special alloy in question would be even more reactive than the planes aluminum, it was designed to be extra shinny, and I believe it was designed by Alcoa Aluminum specifically for the buildings.
http://www.alcoa.com/global/en/news/news_d...1&newsYear=2003
How about a compression(air) artifact or reaction, the plane was nearly supersonic after all.
I really think it was static electricity discharge due to the planes high speed movement through dense, humid air.
Grumpy
I really think it was static electricity discharge due to the planes high speed movement through dense, humid air.
Grumpy
Well, I just "finished the Internet", and it appears that no one
in the world sees the light (except the perps, of course), so...
It don't look like no discharge, no short, no anything
except what it looks like - a light, a high-intensity,
short burst of infrared light triggered by fuselage proximity/contact.
(Hi-intensity to make it thru the windows and trigger the narrow
band high threshold sensors for locale input to the "special CD system").
in the world sees the light (except the perps, of course), so...
It don't look like no discharge, no short, no anything
except what it looks like - a light, a high-intensity,
short burst of infrared light triggered by fuselage proximity/contact.
(Hi-intensity to make it thru the windows and trigger the narrow
band high threshold sensors for locale input to the "special CD system").
Toto
Well, we're not in Kansas anymore.
Grumpy
Well, we're not in Kansas anymore.
Grumpy
QUOTE (Grumpy+Jul 13 2008, 03:54 AM)
How about a compression(air) artifact or reaction, the plane was nearly supersonic after all.
I really think it was static electricity discharge due to the planes high speed movement through dense, humid air.
Grumpy
Grumpy,
Yours seems like the best explanation. It explains:
1) The color;
2) The flash's appearance right before contact;
And the biggie...
3) Why we don't see any other flashes along the wings.
Max
I really think it was static electricity discharge due to the planes high speed movement through dense, humid air.
Grumpy
Grumpy,
Yours seems like the best explanation. It explains:
1) The color;
2) The flash's appearance right before contact;
And the biggie...
3) Why we don't see any other flashes along the wings.
Max
The protrusions appearing beneath the fuselage are curious, because only specialized aircraft display such external devices.
It is also, my understanding that fuel, especially after its' been agitated, generates a serious charge potential. Maybe wing "wicks" can't readily, address the charge building up around the fuel tanks, traveling through or on, the aircraft's internal sub structure. Since the "impact flash" supporters, have so generously explained the presence of metallic components through the surface of the radome, that charge has a path to the nose.
I speculate about the possibility of those jets being fuel tankers because:
1) It could explain the dramatic discharge
2) It could explain the protrusions
3) It could explain why NIST's estimation of the residual fuel was so conservative. They weren't considering additional capacity beyond that of a commercial aircraft.
It is also, my understanding that fuel, especially after its' been agitated, generates a serious charge potential. Maybe wing "wicks" can't readily, address the charge building up around the fuel tanks, traveling through or on, the aircraft's internal sub structure. Since the "impact flash" supporters, have so generously explained the presence of metallic components through the surface of the radome, that charge has a path to the nose.
I speculate about the possibility of those jets being fuel tankers because:
1) It could explain the dramatic discharge
2) It could explain the protrusions
3) It could explain why NIST's estimation of the residual fuel was so conservative. They weren't considering additional capacity beyond that of a commercial aircraft.
QUOTE (Toto+Jul 12 2008, 11:08 PM)
... infrared light ...
Dogs can see into the infrared.
Dogs can see into the infrared.
Some snakes certainly can...
QUOTE (einsteen+Jul 14 2008, 12:44 PM)
Some snakes certainly can...
Do snakes watch those videos?
Do snakes watch those videos?
What about the charged capacitor that powers the radar?
Chainsaw,
Or the microwave's effect on the aluminum cladding???
Grumpy
QUOTE
What about the charged capacitor that powers the radar?
Or the microwave's effect on the aluminum cladding???
Grumpy
Sorry, I don't find violent chemistry or static discharge very likely. Capacitor would be an example of an electric short. Doubt radar powerful enough to melt aluminum.
David B. Benson
But there is a reason you are not supposed to put aluminum foil in a microwave, I'm not saying it melted anything, but it could have flashed like a flash bulb or strobe light. Aircraft radars are much more powerful than a microwave oven.
Grumpy
But there is a reason you are not supposed to put aluminum foil in a microwave, I'm not saying it melted anything, but it could have flashed like a flash bulb or strobe light. Aircraft radars are much more powerful than a microwave oven.
Grumpy
QUOTE (David B. Benson+Jul 15 2008, 08:56 PM)
Sorry, I don't find violent chemistry or static discharge very likely. Capacitor would be an example of an electric short. Doubt radar powerful enough to melt aluminum.
I also don't think it's likely that a plane is charged with some Coulombs. That would then imply that they discharge planes at the airports. Btw I guess we are now talking about the impact flashes when the nose hits the building and not the laser dOt.
I also don't think it's likely that a plane is charged with some Coulombs. That would then imply that they discharge planes at the airports. Btw I guess we are now talking about the impact flashes when the nose hits the building and not the laser dOt.
QUOTE (einsteen+Jul 15 2008, 03:13 PM)
Btw I guess we are now talking about the impact flashes when the nose hits the building ...
Yes. Flashes or just one flash?
Grumpy --- What happens if you put aluminum foil in a microwave?
Yes. Flashes or just one flash?
Grumpy --- What happens if you put aluminum foil in a microwave?
David B. Benson
If it is perfectly flat you get edge currents of electric energy. Any crease or rough edge concentrates these currents to the extent that it melts holes in the relatively thin foil. A crumpled ball of aluminum foil will hiss and spark as long as microwave energy is applied, creating light flashes.
In the case of wtc2 the flash is seen JUST BEFORE contact in an oval shaped area similar to the output pattern of a weather radar. More research needs to be done before any scenario is summarily dismissed.
Grumpy
QUOTE
Grumpy --- What happens if you put aluminum foil in a microwave?
If it is perfectly flat you get edge currents of electric energy. Any crease or rough edge concentrates these currents to the extent that it melts holes in the relatively thin foil. A crumpled ball of aluminum foil will hiss and spark as long as microwave energy is applied, creating light flashes.
In the case of wtc2 the flash is seen JUST BEFORE contact in an oval shaped area similar to the output pattern of a weather radar. More research needs to be done before any scenario is summarily dismissed.
Grumpy
Grumpy --- Thanks! Until further evidence or ideas pop up, I'll go with your analogy.
A metal embedded in an electromagnetic field is something completely different than a charged metal hitting an other metal. I guess it will mainly be a very small electric field although the flashes don't look like electrical discharging.
PhysOrg scientific forums are totally dedicated to science, physics, and technology. Besides topical forums such as nanotechnology, quantum physics, silicon and III-V technology, applied physics, materials, space and others, you can also join our news and publications discussions. We also provide an off-topic forum category. If you need specific help on a scientific problem or have a question related to physics or technology, visit the PhysOrg Forums. Here you’ll find experts from various fields online every day.
To quit out of "lo-fi" mode and return to the regular forums, please click here.