Page 11 of 13

Posted: Thu Sep 04, 2008 11:18 am
by Smurph
R. Prime wrote:I still maintain that if you kick out a big fat pirate's wooden leg, he's gonna fall sideways, not collapse into a puddle.
Yeah, but if you cut off his head he'll drop straight down... I thought someone already covered that?

Totally agree that Bush is an absolute crook though.

Posted: Thu Sep 04, 2008 11:21 am
by psj3809
R. Prime wrote:In all honesty do you deny that when you watch the news you take for granted that it is a fair representation of the truth? I used to. Now I actually think about it. You only have to look at the mainstream coverage of the recent Georgian war, and consider that it was Russia who was attacked to become a bit thoughtful.
Course i dont, i dont think most people here would take what they hear for granted 100% but on the other hand i dont believe we're purposely being force fed government propaganda week in week out. I think thats a bit too 'X-Files' and something out of the film 'They Live'. Its insulting when you originally started this thread making out we're all just 'followers' and dont have our own mind. Same again with the above, of course people dont accept 100% what they read/her. All because we dont believe your 911 bull doesnt make us a frickin robot.

But just as i sometimes take news articles with a pinch of salt and realising how biased 'some' are , on the other hand i also dont take so seriously some nuts on the internet spouting rubbish and making out its all true as theyve showed a few graphics, a few paragraphs from their physics GCSE and start sprouting even more biased views to people.

Dont mean necessarily you but the internet has given many wackos a voice to be heard by other wackos.

As for Iraq i do think its about oil but also Saddam didnt help matters. If he let in UN teams from day 1 constantly then the US would have even had less of a excuse to go in there and would have received condemnation from everyone.

Sadly in a very selfish way i have other things to worry about, as much as Iraq is terrible, other countries are out there killing people for having a voice etc, theres tons of bad stuff going on in the world. As much as i would love to give my time to all these problems I just cant

Posted: Thu Sep 04, 2008 1:29 pm
by RetroKingSimon
Dudley wrote:At the risk of being obvious about the previous north tower fire too, I'm going to go ahead and guess that a fire in a building damaged by 400 tonnes of aircraft slamming into it, and fuelled by 50,000 gallons of avaiation fuel is going to be just a smidgen hotter than one started up some idiot dropping a cigarette in a perfectly healthy building.

(I didn't check how the 1975 fire started, going to go ahead and assume it
wasn't a 767 though).
Exactly what I was thinking when I saw those amusing video clips :lol:

Posted: Thu Sep 04, 2008 5:42 pm
by R. Prime
As for Iraq i do think its about oil but also Saddam didnt help matters. If he let in UN teams from day 1 constantly then the US would have even had less of a excuse to go in there and would have received condemnation from everyone.
Too true. I think the reason for going into Iraq was not just to secure the oil supply, but that Iraq had just started to trade oil only in Euros. This would lessen the need for countries to keep large amounts of US dollars in reserve, which they do currently to lessen exposure to currency fluctuations. This requirement keeps demand for the US dollar high, which in turn props up the value.
If they hadn't invaded, you might have had Iran and Venezuela following suit, which would mean big recession for the US.

Posted: Thu Sep 04, 2008 6:55 pm
by jimbo_too
R. Prime wrote:Just to come clean, I did receive a national scholarship in Physics in my last year at high school, and did (pass) a stage 1 physics paper in one of my 2 bachelor degrees. I didn't find physics very inspiring TBH.
Your opinion seems to be that if we don't buy your argument we are stupid.
Well this is not true, this is a common misconception about this thread. I said "It baffles me how sometimes smart people don't think very hard about what they're told." And then said most retro enthusiast (myself included) are generally smart guys. I was just trying to phrase it in a way weighted against the status quo. Conspiracy theories are generally considered to be "stupid", I tried to invert it. Backfired though it seems. :)

In all honesty do you deny that when you watch the news you take for granted that it is a fair representation of the truth? I used to. Now I actually think about it. You only have to look at the mainstream coverage of the recent Georgian war, and consider that it was Russia who was attacked to become a bit thoughtful.

(If you'll allow me to use bold typeface here to make my final point)

The Bush administration has shovelled some serious sh!t over the last 8 years, here's a timeline, these guys are just criminals. Even if they didn't do it, then they should be held accountable for the million+ actual human deaths they have caused in Iraq due to their bogus invasion. Tell me we can agree on this then?

Come on...
The number sounds a bit spurious. I imagine that it will be a long time before we know how many people died in Iraq, but I've never seen a figure even vaguely that high, even from Human Rights Watch or Amnesty.

I think the Iraq war was a load of b*llocks, perhaps a bit of score-settling, maybe a way for W to get one over his dad (they are not close). What Russia did was wrong, but we have done worse recently and we can't point the finger of blame without becoming hypocrites (and do we dare risk our gas supplies?).

But I still don't think that 9/11 was an act of politically-motivated sabotage. I wouldn't put it past Bush, I just don't think he did it.

Posted: Thu Sep 04, 2008 7:41 pm
by Bub&Bob
R. Prime wrote:Just to come clean, I did receive a national scholarship in Physics in my last year at high school, and did (pass) a stage 1 physics paper in one of my 2 bachelor degrees.
That's pretty impressive.
R. Prime wrote:Ok Emperor Fossil, you have outphysicksed me
How did you get on in your PHD in "making up words"?
:wink: :wink:

Posted: Thu Sep 04, 2008 8:56 pm
by Emperor Fossil
I must admit, I'll be glad to see this argument fizzle out. I don't come to this forum to argue. In fact, I don't even really like getting into arguments and heated debates full-stop. Mind you, I must admit that the internet provides plenty of material that encourages mass debating. (hurh hurh! Geddit?)


Just to clarify something though: Although I think the 'controlled demolition' theory is a load of old bollocks, that doesn't mean I'd rule out the possibility of some kind of dodginess on the part of US authorities being mixed up somewhere in the whole tragedy.

For example: The properties of steel depend on how and with what it is alloyed. Is it possible that the steel used in the construction of the twin towers wasn't as high quality as it could or should have been? If that were the case, would the investigators disclose this? I don't know. Either way, it's just idle speculation on my part, and I think it's important to recognise idle speculation as such and not get too carried away with it. Besides, for all I know the relevant info might already be out there.

I also wouldn't be surprised if there was some degree of covering up going on regarding the failure of the authorities to prevent the attacks. You have to wonder to what extent organisational ineptitude and a lack of communication between organisations (and between departments within organisations) played a part in failing to prevent what happened. Again that's speculation with no attempt to find out more on my part, but I'm just saying that doesn't seem unlikely to me that this could be the case. Would I go as far as entertaining the notion that key figures allowed it to happen? I'd like to say that seems unlikely, but hey, who knows?


R. Prime wrote:(If you'll allow me to use bold typeface here to make my final point)

The Bush administration has shovelled some serious sh!t over the last 8 years, here's a timeline, these guys are just criminals. Even if they didn't do it, then they should be held accountable for the million+ actual human deaths they have caused in Iraq due to their bogus invasion. Tell me we can agree on this then?

Come on...
Well, I think this is where we start to share more common ground. I have no love for the Bush administration whatsoever. Colin Powell seemed to be the only one worth a damn, but he still shovelled up a load of bullshit regarding biological weapons in Iraq. The whole charade by the Bush admin of mounting an anti-al Quaeda/anti-Taliban attack on Afghanistan only to shift the focus to Iraq the first chance they had was appalling, as was/is the amount of misinformation and lies they dished out in order to cultivate public support for their intended course of action. Yes, Saddam was a terrible figure, and I accept that many Iraqis would have been happy to see him removed, but the Bush admin really seem to have given little thought (or little care) at the time to what would happen after that. Or maybe they honestly thought it would be 'easy'. And then of course there's the question of whether the US is entitled to interfere and to go against the UN, and why they were so determined to take action here and not in other, non-oil producing regions.

To be honest, although I've been a bit snarky about conspiracy theorists in this thread at times, I can't help but feel that it's a testament to how dodgy the Bush admin has been over the years that these theories go as far as they do.

Posted: Thu Sep 04, 2008 10:18 pm
by Smurph
Colin Powell seemed to be the only one worth a damn, but he still shovelled up a load of bullshit regarding biological weapons in Iraq.
I think he admitted that he went full-steam ahead on information he was given and then realised that it was a pile of stinking horse-poo, hence the resignation.

Posted: Fri Sep 05, 2008 4:36 am
by R. Prime
I was trying leave this alone, honestly, but then someone has another go and calls me a wacko or a steaming poo-handler or something and I have to defend myself. Full steam ahead then.
I am talking primarily about the collapse here (which hasn't been successfully modelled or proven by NIST), not the aeroplane impact and fire.
When looking at the resultant motion in any collision, you have to factor in the mass and hence the inertia of the objects in question, and the same applies in the case of the mass of the upper part of the towers falling onto the floors below, hitting each floor in turn and propagating a collapse that is only going to intensify as it proceeds due to the increasing amount (and therefore mass) of the falling material. Remember, you can't treat the body of the tower below the impact zone as a 'solid block', no matter how much you might wish to.
I said the tower body was "effectively a solid block" as a simplification, to get you to at least consider the resistance that it would provide and the time it would take to overcome this resistance.

If we assume that the upper section comprising 16 storeys falls under a full gravitational acceleration through a height of one (removed) storey, a distance of 3.7 metres we can calculate that its velocity upon impact will be 8.52 metres per second and have a kinetic energy due to its mass and velocity of 2.105 GJ. (Using the figure of 58000 tonnes as detailed in the pro-collapse report by Bazant & Zhou.) In reality there would be some added losses of energy due to residual strength within the failing columns of the removed section, but we can ignore them here in favour of the collapse theory.

Upon impact with the lower section the falling mass would deliver a force which would grow from zero, up to the failure load of the impacted storey columns, over a finite period of time and distance.

This force would also be felt by the columns below the storey which was first impacted.

The falling upper section with a velocity of no more than 8.5 metres per second at impact would meet resistance from the impacted columns and have as its first task the necessity to load these columns through their elastic range and thereafter through the plastic shortening phase.
Timewise, looking at the B&Z report, To shorten the columns of the first impacted storey by 3%, sufficient to complete the plastic shortening phase, a distance of about 0.111 metres, and allowing a constant speed of 8.5 metres per second, would take a minimum of 0.013 seconds.

The speed of the propagation wave through a medium is given by the general formula for wave propagation:
Velocity = Square root ( Bulk modulus / Density ),
and for structural steel is of the order of 4500 metres per second.
The propagation wave of the impact force would therefore travel a distance of 58.7 metres over 0.013 seconds. This means that during the time taken in the plastic shortening of the impacted columns, the same force would be felt at a minimum distance of 58.7 metres (~16 storeys,) from the impact. These storeys would thus suffer an elastic deflection in response to, and proportional to, the failure load applied at the impacted floor. These deflections would themselves take time and allow the propagation wave to move further downwards again affecting more storeys.

We can estimate the elastic deflection of these 16 storey columns as being in the range 0 to 7mm. The full elastic deflection of a 3.7m column, using the generally accepted figure of 0.2% of its original length is 7.4mm. The columns in the uppermost of these storeys would suffer almost their full elastic deflection since their failure load is similar though slightly greater than that of the first impacted storey. Those storey columns more distant from the impact would be of
a larger cross section, requiring higher loads to cause full elastic deflection. Using only half of the maximum elastic deflection, 56mm (16 * 7 / 2), is, again, an assumption in favour of collapse continuation.

The elastic deflection of lower storeys would increase the distance through which the falling section would have to move in order to load the impacted column and complete its 3% plastic shortening. The time taken, again using a constant velocity of 8.5 m/sec would increase to about 0.02 seconds, and thus allow the propagation wave to move through and affect a further 8 storeys.
And yes, the structure - or rather, each floor as the weight of the collapsing material impacts on them in turn - will exert a force on the falling load equal to the force that load exerts on it, but that doesn't mean it will halt the motion of that load.
You will still get significant energy/momentum loss due to to the resistance of the structure.

A simple conservation of momentum calculation, ignoring these movements/deflections (in your favour again), would have, 16 falling storeys moving at 8.5 m/sec before impact, changing to 17 storeys moving at (8.5 * (16/17)) = 8 m/sec after impact. This does not reflect the fact that a minimum of 24 further storeys will be caused to move downwards at varying speeds. Assuming a storey 25 storeys from impact remains static,

Momentum before impact = 16 storeys moving at 8.5 m/sec
Momentum after impact = 17 storeys moving at V2 m/sec + 1 storey moving at 23/24*V2 m/sec
+ 1 storey moving at 22/24*V2m/sec +……+ 1 storey moving at 2/24*V2 m/sec + 1 storey
moving at 1/24*V2m/sec 16*8.5 = V2 (17 + 11.5)

V2 = 16 * 8.5 / 28.5 = 4.8 metres per second.

The speed of the upper section would be reduced by the collision from 8.5 m/sec to a speed of less than 4.8 m/sec rather than the 8 m/sec derived from a momentum calculation which does not include this factor. Note also that this reduction in speed would again give more time for the propagation wave to travel downwards through the tower columns and allow that more and more storeys are so affected.
Now think about the kinetic energy of a falling weight
Ok.
The kinetic energy of the falling section would be similarly affected, but because of the velocity squared relationship, the reduction in kinetic energy would be more pronounced.

K. E. of falling section before impact = 16 floors moving at (8.5 m/sec)
K. E. of falling section after impact = 17 floors moving at (4.8 m/sec)
Percentage loss of K.E. = 1-(17 * 4.8/ (16 *8.5) * 100% = 66%

This is an underestimation of the energy loss, since the deceleration would allow more time for travel of the propagation wave and so allow more floors to be affected but even this shows an energy absorption of some 66% of the total kinetic energy of the falling section.

Since there was only some 2.1 GJ available at the point of impact of the first collision, a loss of 66% would reduce this figure to 714 MJ.

You still have other energy losses due to:

- compression and using the same deflections as above and a value for mass proportionate to the number of storeys.
- elastic response of the lower storey columns within their elastic range
- plastic strain energy loss that would increase the further down the structure you go, as lower stories would necessarily have to support more load.
- compression and consequent movement of the storeys within the upper section
- (looking at Dr. Frank Greening's report - someone who doesn't follow the "conspiracy theory" by the way)the energy required to pulverise approximately 50000 tonnes of concrete into the fine dust which was evident from the photographic and other evidence.
One kilogram of concrete at this particle size will have a surface area of 67 m^2.
Using Dr. Greening's figure for concrete fracture energy (100J/m^2) the
energy requirement for one floor itself would be ( 50*10^6kg / 110floors * 67m^2 * 100J/m^2 * 10% = ) 304 MJ!
It may be considered unlikely that a low velocity impact would expend large energies on pulverisation of materials, and this is more likely in later stages of the collapse. However, the large expulsions of dust were visually evident at early stages of the collapse.

Image
Fig 1. "Poof."

Let me know if you'd like to see the calculations for all of the above. Then there's also:

- disconnection of the floor to column connections
- damage caused to spandrel plates or other structural elements
- crushing of floor contents
- any strain energy consumption during the initial fall through the height of one full storey

With only 2.1 GJ available at the point of impact of the first collision, the energy balance of the collapse moves into deficit during the plastic shortening phase of the first impacted columns. There isn't enough energy to propagate the collapse, let alone all to account for any of the additional loss factors. A collapse driven only by gravity would not continue to progress beyond that point.

(I did get help from a structural engineer on the above, I'm sure you've figure that out for yourself though.)
My point is that it wouldn't hurt you to bring some of scepticism you bring to the official reports to all these youtube videos you're devouring.
Dude, I do. Some of them propound some great theories that are absolute bollocks. like:
- There were never any planes at all, they were missiles wrapped in holograms (this guy also thinks he is the messiah)
- The towers were brought down by an energy weapon from space.
This is not to say that all conspiracy theorists believe this, which is a generalisation a lot of people seem to leap to.

Stop calling me names and I will stop arguing! :wink:

Posted: Fri Sep 05, 2008 4:39 am
by R. Prime
re: stinking poo

Sorry you were talking about Colin Powell, I agree with you there.

Posted: Fri Sep 05, 2008 5:30 am
by Smurph
Nutjob.























:wink:

Posted: Fri Sep 05, 2008 7:58 am
by psj3809
Emperor Fossil wrote:I must admit, I'll be glad to see this argument fizzle out. I don't come to this forum to argue. In fact, I don't even really like getting into arguments and heated debates full-stop. Mind you, I must admit that the internet provides plenty of material that encourages mass debating. (hurh hurh! Geddit?)


Just to clarify something though: Although I think the 'controlled demolition' theory is a load of old bollocks, that doesn't mean I'd rule out the possibility of some kind of dodginess on the part of US authorities being mixed up somewhere in the whole tragedy.

For example: The properties of steel depend on how and with what it is alloyed. Is it possible that the steel used in the construction of the twin towers wasn't as high quality as it could or should have been? If that were the case, would the investigators disclose this? I don't know. Either way, it's just idle speculation on my part, and I think it's important to recognise idle speculation as such and not get too carried away with it. Besides, for all I know the relevant info might already be out there.

I also wouldn't be surprised if there was some degree of covering up going on regarding the failure of the authorities to prevent the attacks. You have to wonder to what extent organisational ineptitude and a lack of communication between organisations (and between departments within organisations) played a part in failing to prevent what happened. Again that's speculation with no attempt to find out more on my part, but I'm just saying that doesn't seem unlikely to me that this could be the case. Would I go as far as entertaining the notion that key figures allowed it to happen? I'd like to say that seems unlikely, but hey, who knows?


R. Prime wrote:(If you'll allow me to use bold typeface here to make my final point)

The Bush administration has shovelled some serious sh!t over the last 8 years, here's a timeline, these guys are just criminals. Even if they didn't do it, then they should be held accountable for the million+ actual human deaths they have caused in Iraq due to their bogus invasion. Tell me we can agree on this then?

Come on...
Well, I think this is where we start to share more common ground. I have no love for the Bush administration whatsoever. Colin Powell seemed to be the only one worth a damn, but he still shovelled up a load of bullshit regarding biological weapons in Iraq. The whole charade by the Bush admin of mounting an anti-al Quaeda/anti-Taliban attack on Afghanistan only to shift the focus to Iraq the first chance they had was appalling, as was/is the amount of misinformation and lies they dished out in order to cultivate public support for their intended course of action. Yes, Saddam was a terrible figure, and I accept that many Iraqis would have been happy to see him removed, but the Bush admin really seem to have given little thought (or little care) at the time to what would happen after that. Or maybe they honestly thought it would be 'easy'. And then of course there's the question of whether the US is entitled to interfere and to go against the UN, and why they were so determined to take action here and not in other, non-oil producing regions.

To be honest, although I've been a bit snarky about conspiracy theorists in this thread at times, I can't help but feel that it's a testament to how dodgy the Bush admin has been over the years that these theories go as far as they do.
Yep totally agree with all of that. You know your stuff. You've changed my opinion.

Anyway moving on, Manic Miner or Chuckie Egg ?

Posted: Fri Sep 05, 2008 8:06 am
by mikeb
Is this thread still going? :roll:

Posted: Fri Sep 05, 2008 9:33 am
by TMR
mikeb wrote:Is this thread still going? :roll:
No, s'just a conspiracy to make you think it's still going!!

Posted: Fri Sep 05, 2008 10:09 am
by Emperor Fossil
R. Prime wrote: < Huge amounts of copy and pasting from Gordon Ross's article, available at http://gordonssite.tripod.com/id1.html >
This would have to be the funniest thing I've seen on these forums. Stuck for an argument and mistakenly believing that I had called you a name or something, you run off in search of ammunition and end up copying and pasting Gordon Ross's article almost in its entirety, making just a few small rearrangements to keep the length down.

Seriously dude, why not just link to the site? Were you trying to make yourself seem smarter than you are?
(I did get help from a structural engineer on the above, I'm sure you've figure that out for yourself though.)
hahah. Yes, great help of the Ctrl-C, Ctrl-V kind. Should I now run off and find comments made by others who have found fault with his article, for example those who say that he uses a flawed model of the collapse, and paste them here? Should I copy and past the comments made by others about Ross's failure to get other engineers to take him seriously? Or why his 'papers' haven't made it into any science journals?

I mean what's the point? I don't believe for a moment that you understood much of what you were copying and pasting. I certainly didn't, but then, I must admit, I didn't bother reading much of it either. As soon as I hit the first technical paragraph I thought "Hello, someone's used the phone-a-friend option here" and started laughing. And then of course I fed a line into Google, and laughed some more.

By the way, Ross is trained as a mechanical engineer and as a manufacturing engineer. He's not a structural engineer. Just thought I should mention that for next time you get some 'help' from him. :lol:

Also, I'm honestly surprised to find that when I wrote "Colin Powell seemed to be the only one worth a damn, but he still shovelled up a load of bullshit regarding biological weapons in Iraq." You thought I was calling YOU "steaming poo-handler or something." I mean, WTF man? How the hell did you arrive at that? Is your real name Colin Powers or something?

Anyway, I'm not going to play this copy-paste game with you. It's a silly game, played by poo-handlers!

Mind you, one thing your post did achieve is that it highlighted how ridiculous it is for ordinary Joe Blows like yourself or myself to attempt to discuss something like this in any real depth. In the end, we have to look to the opinions of those who are educated and experienced in these matters. And if we do that, it makes sense to me that we should go with the majority, rather than the odd lonely voice publishing his views on a tripod.com site.


psj3809 wrote:Anyway moving on, Manic Miner or Chuckie Egg ?
Well, it has to be Manic Miner doesn't it? You know... cos of DA GUV'MENT!