Moderated What Caused the Plane Shaped Hole

GlennB said:
"The math" would not only be massively complicated it would also be massively varied. Loads, forces, dimensions, material properties, stresses, strains ....

"The math" would probably occupy hundreds (thousands?) of sheets of printer paper.

There is no chance on earth you'd understand it. You know this, so constantly asking to see "the math" is just your very dishonest way of denying the arguments lined up against you without having to explain why.
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Some reading material for Steve to ignore:

http://www.math.umn.edu/~sayas002/anIntro2FEM.pdf
 
yankee451 said:
I'm not the one claiming there's an FEA backing up the Purdue cartoon.
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I'll back that horse, and I've posted links to 2 other FEA studies that corroborate the core question here, whether an airliner at high speed has enough kinetic energy to penetrate the building.

So far you've ignored the information provided.

My claim is that the math they claim they used is not available to the general public,
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You have been repeatedly told that "the math" is not a single equation on the back of an envelope. "The math" is widely used in both aviation and automotive industry to simulate high energy collisions, as well as modeling structures to test for design flaws before expensive construction starts.

Not sure what your trade is, but there are people who use FEA every day. "The math" is very complicated and requires enormous computational resources to accomplish in human scale time frames.

as DGM learned the hard way a couple days ago. If the link existed (it doesn't) it's safe to say one of the OS faithful would have produced it by now.
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We've sent you link after link after link. Your refusal to actually read them brings us back to something you said upthread. You made a reference to Diogenese in your "search for an honest engineer." I've been wandering the internet with my lamp searching for an honest truther for years. So far I've found one -- a guy at DIF (I, know, hard to believe) started out as a no planes believer and finally got banned when he became increasingly unconvinced of the nope lamer "theory" and started arguing the other side.

Not only have we sent you link after link discussing FEA in general, the specific FEA software used by Purdue and the reports by 2 OTHER teams of researchers, but we have given you some very VERY basic math to start down your own path of knowledge. You are a fine example of the horse who has been led to water.

Drink this:

f=ma means force equals mass times acceleration.

The mass of the 767 can be rounded down to 300,000lbs without causing anyone to freak out. The speed of the planes that hit the towers can be rounded to 500mph without anyone freaking out. The 767 is close enough to 180 feet long that we can use that for this extremely oversimplified "the math."

Putting those numbers into the imaginary scenario I tried to spoon-feed you upthread (the one with the concrete wall a million miles thick) we have a mass of 300,000 lbs decelerating from 500mph (733 feet per second) to zero in the amount of time it takes the mass to travel 180 feet, which works out to about 0.25 seconds.

That means the mass would decelerate from 733fps to zero in .25 seconds.

Plugging numbers in to this calculator http://www.calctool.org/CALC/phys/newtonian/fma
I come up with 27,338,800 foot-pounds of force applied by the mass to the target.

using this link
http://books.google.com/books?id=V1...w#v=onepage&q=767 wing root thickness&f=false
I estimate the wing and fuselage frontal area at between 800 and 1000 square feet. I'll round up to 1000 so that gives us 27338.8 psi applied by the decelerating mass to the target.

In the case of the WTC the columns are only 40% of the surface area, so that puts us at 68,000 pounds per square inch applied to the columns. I'm pretty sure the columns were designed for vertical loads not horizontal. I'll let you find the modulus of elasticity for the steel beams and various connections.


http://www.convert-me.com/en/convert/speed/

f
 
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yankee451 said:
I'm not the one claiming there's an FEA backing up the Purdue cartoon. My claim is that the math they claim they used is not available to the general public, as DGM learned the hard way a couple days ago. If the link existed (it doesn't) it's safe to say one of the OS faithful would have produced it by now.
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Some of that has to do with the fact that it takes years of study to understand it. Your inability to grasp the higher math is not an indication of in accuracy.
 
Jack by the hedge said:
Nitpick on units: "lbf" is pounds (force) not foot-pounds.

(This is why I like metric. It's less quirky.)
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Dammit, Jim! I'm a carpenter, not a mathematician!



Which is to say, if you have corrections please post them. Unlike the OP I'll read and learn.
 
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This thread is closed pending clean up, infractions, etc. As always, do not use other threads to get around the closure. You'll have to wait until the thread reopens.
Replying to this modbox in thread will be off topic  Posted By: LashL
 
This thread has been cleaned up. In order that it doesn't become a pig sty in a few hours after reopening, it'll be set to Moderated status. As always, do not start other threads to get around this status.
Replying to this modbox in thread will be off topic  Posted By: kmortis
 
For those that want to see what it looks like in practice, I've uploaded a simple problem solved with FEA. This is a simple analysis of a 3 degree of freedom beam with two point loads. It is linear, and elastic.

The global stiffness matrix of my problem is 12x12. The global stiffness matrix for the analysis conducted by NIST would be in the order of 100,000x100,000. Printing that out would be a pile of useless gibberish. However the analysis conducted by NIST also goes a step further than this. My problem solves [K]{d} = {r}. Put plainly, it's the resting state of the problem (no vibration, etc). NIST solves the problem and solves the FEA problem many times per second. The output would be millions (if not billions) of pages of matrices. Asking to "see this math", as one here has demanded, is a completely ludicrous demand that anyone with a modest knowledge of FEA and engineering would know.
 
Video and Radar evidence prove Flt 11 and 175 caused the plane shaped holes


Flight 11 hits the WTC, on film, with the exact fireball 67,000 pounds of jet fuel would make. Time of impact for 11 match the time for video and Radar.
Radar data proves it was Flight 11.
http://www.ntsb.gov/about/Documents/Flight_Path_Study_AA11.pdf
Evidence proves it was 11.

If the video for Flt 11 is gone, search for - naudet video of 11 impact

Flight 175, seen by thousands, made the other hole - it is a fact, not speculation, not fantasy.
The video matches the same time as the Radar data.
http://www.ntsb.gov/about/Documents/Rec_Radar_Data_Study_all_aircraft.pdf
Radar and video prove it was 175 that made the aircraft shaped hole, not magical missiles, or other claims.
If the video for Flt 175 is gone, search for - flight 175 impact
There are many independent videos of Flt 175 impact.
 
 
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More mocking the murdered of 9/11 with nonsense. The ceiling fell... and you make up BS.

The impact of Flt 11 an Flt 175 were equal in kinetic energy to the energy in 1300 and 2093 pounds of TNT.

You show photos of fallen ceiling tiles, and speculate and spread BS. Why do you spread lies and nonsense?

Why do you lie about 9/11? Oh, yes you said you make up lies to end War.

There should be a war on posting lies and nonsense, the kind you do mocking the murder of fellow Americans by failed UBL murderers.
 
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Like most modern office buildings, the Twin Towers had "drop ceilings", hung from the floor trusses above them. When the building was hit, many fell. Try to get in touch with the real world. :mad:
 
Redwood said:
Like most modern office buildings, the Twin Towers had "drop ceilings", hung from the floor trusses above them. When the building was hit, many fell. Try to get in touch with the real world. :mad:
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I assume you're talking about the top example. You should watch the video.
 
I think that the evidence shows that the windows went "missing" where a very large plane flew into it.
 
Wolrab said:
Silly, they're just rolled down.
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What are you referring to, the screens covering multiple floors, or the canvas window coverings that were attached to the frames?

In each example there isn't a shard of glass visible, so if you're referring to white material attached to the frames, you're telling me that you believe a jet bored through there and obliterated all the glass (but didn't fully penetrate the wall - oops, don't tell Purdue!) but didn't have enough force to tear through the blinds? They're attached to the frames - you can see one frame bent with the fabric attached to it.
 
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