Stupid People like this are as big a danger to this country as any racist

[Mikeanaro]

You certainly can't dismiss the prospect given the mass of the planes, their speed and the nature of the fireproofing, which in many cases was just sprayed directly on the steel. It's not impossible to model the results of an impact since so many factors are known.

The mass of the planes? those were beer cans compared to a huge concrete Tower, worst case scenario you can take down one third of the building but you wont take everything down.
Now, it they could hit the towers from bottom to almost half (not the top) that would be another story because you are messing with the foundation.

[Pavlov]

The mass of the planes? those were beer cans compared to a huge concrete Tower, worst case scenario you can take down one third of the building but you wont take everything down.
Now, it they could hit the towers from bottom to almost half (not the top) that would be another story because you are messing with the foundation.

Tell you what. Have a beer can thrown at your face at 500 mph and tell me if it does any damage to you.

[RandomGuy]

Tell you what. Have a beer can thrown at your face at 500 mph and tell me if it does any damage to you.

A beer can with some stacks of quarters taped to it. The solid, high-performance steel in the engines meant that there were several very solid 8000 pound objects slamming through the building.

Bear in mind that the physics of moving objects means that the kinetic energy goes up by the square of the speed, meaning that an 8000 pound object moving at 550 mph will have 7.5 times the kinetic energy of one moving at 200mph.

Anyone who thinks that four 8000 pound steel objects moving at 550 mph won't do any structural damage, should pick up a physics textbook.

(edit)

That 8000 pound engine (4 tons) would impact something at that speed with the force of about 2500 TONS of something at rest on the ground.
http://www.csgnetwork.com/kineticenergycalc.html

3636 kilograms
245 meters per second
=109125450 joules

109125450 joules divided by 9.8 m/s (gravity)
equals
2272500 kilograms

2272500 kilograms multiplied by 2.2 pounds per kg
4999500 pounds

4999500 pounds divided by 2000 pounds per ton

2499.75 tons.

[RandomGuy]

An empty 15 gram soda can would hit your face with about 20 pounds of force at 550 mph. enough to break your nose.

[Blake]

The mass of the planes? those were beer cans compared to a huge concrete Tower, worst case scenario you can take down one third of the building but you wont take everything down.
Now, it they could hit the towers from bottom to almost half (not the top) that would be another story because you are messing with the foundation.

I like when message board scrub knows more physics than real engineers do.

[RandomGuy]

Wrong, it may get some parts but then you have cement/concrete/bricks/ceramics everywhere so you cant make an easy formula like its a scientific fact.

You can measure the insulating quality of cement yes. But the trusses that were under the concrete floors didn't have much covering them.

Concrete, while you can put a lot of stuff on top of it, doesn't hold up to shear. That is what steel is for.

Uncontrolled fires put out a lot of heat, and even with insulation after serveral hours, you can measure how much heat any material, such as concrete will absorb. (chemistry = specific heat)

It doesn't take a lot of heat to make the steel soft enough to flex bend and stop providing enough resistive force to counteract gravity, especially the damaged parts that have to take more weight to begin with because damage has redistributed the load to fewer trusses.

This stuff is science.

[RandomGuy]

Enough man, it wasnt enough to melt and take down the whole 500 meter building, first of all the whole tower wasnt on fire so you cant make projections like ¨YES THE WHOLE BUILDING WAS ON FIRE FOR X HOURS AND THE CARBONARO EFFECT HAPPENED SO IT ALL WENT SOUTH!¨
Also you dont go thru the steel so easily, there is cement/bricks/concrete/ceramic sucking all that fire first, is not like fire gets the steel that quickly.

http://www.debunk911myths.org/

http://www.jod911.com/


PE= m *9.8*413= 4073m

Mass is, by definition, simply a measurement of how much force a given amount of material will exert AT REST on an object that is resisting gravity.

SOOOO

The top floor would hit the ground with the same force as a 4073 story building, if that fall was unimpeded.

Now let's consider the fall of the top 30 stories.

They fell through the 3-5 floors of damaged sections and impacted the building below with some amount of force.

Let's call the distance accelerated as 3 floors and be generous. This is 11 meters.

Acceration of an object for 11 meters at 70% of gravity(dan's figure), would yeild an ending velocity of:

v^2= 2ad=2*9.8*.7*11=150=v^2, find the square root of 150, and bada bing, you get 12 meters per second

Subs ute this into the kinetic energy equation:
ke= 150*.5*m=ke=75m

This means the 30 floor section impacts the undamaged portion with the kinetic energy of SEVENTY FIVE TIMES ITS MASS.

Think about this for a moment.

The lower section of the building is designed to hold that 30 stories stationary plus a safety margin of 10 or 20%. So the maximum force that the underlying structure could apply to that falling section is 1.2 times its mass.

Further:
That falling section having as much kinetic energy as 75 times its mass means that it is effectively applying the same amount of force at the impact point that a 2270 story building would. if you held it stationary. (simple math: 30*75)
For the statement "the building would not have collapsed without explosives" implies that the building could have been TWENTY TWO TIMES TALLER THAN IT ACTUALLY WAS without collapsing.

STILL FURTHER

Your calculations seem to imply that the building structure below could absorb 30% of the falling energy.

IN JUST THE FIRST 11 METERS OF A 400 METER COLLAPSE THERE IS 62 TIMES THE AMOUNT OF FORCE REQUIRED TO COLLAPSE THE BUILDING.

Your assumption of about 1/3 the energy used to collapse the building is about 20 times what is reasonable. (1/62*20= 1/3) (more actually, if you consider the further distance and mass)

What happens, then when MORE mass is added AND accelerated?

Even if half the mass falls away or off to the side, there is still FAR more force and energy than would be needed to collapse the building WITHOUT ANY EXPLOSIVES.

[RandomGuy]

I like when message board scrub [thinks he] knows more physics than real engineers do [but very obviously doesn't have a ing clue].

FIFY.

[Mikeanaro]

You can measure the insulating quality of cement yes. But the trusses that were under the concrete floors didn't have much covering them.

Concrete, while you can put a lot of stuff on top of it, doesn't hold up to shear. That is what steel is for.

Uncontrolled fires put out a lot of heat, and even with insulation after serveral hours, you can measure how much heat any material, such as concrete will absorb. (chemistry = specific heat)

It doesn't take a lot of heat to make the steel soft enough to flex bend and stop providing enough resistive force to counteract gravity, especially the damaged parts that have to take more weight to begin with because damage has redistributed the load to fewer trusses.

This stuff is science.

Is not science, you are saying if I go to the top of a building and start a fire the whole building will fall like a card house, lol it doesnt take a lot of heat, so I grab a steel column and I put him on a grill and voila! I have steel cream?
Thats inaccurate, specially that plane part, a plane cant even have a violent landing without losing turbines wings or other parts since its aluminium, but can make a massive damage to a 500 meter tower? enough to bring it down?

[Blake]

You're stupid.

[Mikeanaro]

I like when message board scrub knows more physics than real engineers do.

I like when no brain people likes to discuss without questioning because it doesnt meet their agenda.

[Pavlov]

The best thing about this is poor Mikey thinks he's winning.

[Blake]

I like when no brain people likes to discuss without questioning because it doesnt meet their agenda.

What agenda would that be

[Blake]

The report has been questioned ad nauseum. The conspiracies as well.

If you still think it was something else, at this point you're lazy and/or stupid.

[Mikeanaro]

The best thing about this is poor Mikey thinks he's winning.

Yeah, specially that part where you said there was no record in human history of a plane hitting a building, there you have... empire state.
The best thing is you dont even know the history of your own country... ¨winning¨.

[Pavlov]

Yeah, specially that part where you said there was no record in human history of a plane hitting a building, there you have... empire state.
The best thing is you dont even know the history of your own country... ¨winning¨.

The B-25 isn't a jumbo jet and it wasn't going over 500 mph. I know all about it.

[Pavlov]

And the Empire State building is constructed completely differently. Winning.

[RandomGuy]

Is not science, you are saying if I go to the top of a building and start a fire the whole building will fall like a card house, lol it doesnt take a lot of heat, so I grab a steel column and I put him on a grill and voila! I have steel cream?
Thats inaccurate, specially that plane part, a plane cant even have a violent landing without losing turbines wings or other parts since its aluminium, but can make a massive damage to a 500 meter tower? enough to bring it down?

These two situations aren't entirely comparable.

The maximum weight of a B-25 ranged from 27,100 lb to a limit of 41,800 lb, for instance (see http://www.warbirdsresourcegroup.org...5mitc .html). A 767-200 ranges from 179,080 lbs (empty) to 395,000 lb (maximum takeoff load) (www.aerospaceweb.org/aircraft/jetliner/b767), and FEMA said the 9/11 planes had “an estimated gross weight of 274000 pounds” ( http://www.fema.gov/pdf/library/fema403_ch1.pdf ).

The maximum speed of a B-25 ranged from 275 mph to 315 mph, depending on which version it was, and as the B-25 pilot was trying to avoid the building it's unlikely he'd have reached that (cruising speed was 230 mph). On 9/11, "American Airlines Flight 11 crashes at a speed of roughly 470 mph" and "United Airlines Flight 175 crashes at a speed of about 590 mph" (http://channel.nationalgeographic.co.../timeline.html), a considerable difference when you factor in the extra mass as well.

So, let's do some more math.

http://www.csgnetwork.com/kineticenergycalc.html

B-25 at roughly median weight of 35,000 pounds. 747 at 274,000 pounds.

747 is 7.828571 times as massive.

230 mph is 102 meters per second
550 mph is 245 meters per second

For sake of simplicity call the bomber 1 kg, because we are comparing two objects.
1kg moving at 102 meters per second
2178 joules


An object 7.82 times as massive moving at 245 m/s
7.8kg moving at 245 meters per second
234097.5 joules

234097.5/2178 =107

The jetliner hit the building with more than 100 times the force that the B-25 did, and that is giving more mass and speed to the bomber than it probably had.

The jetliner had more fuel, more mass, and most importantly from a physics stand point, more speed.

Double the speed and the kinetic energy goes up by a factor of four.

This ignores differences in construction as well.

[RandomGuy]

[RandomGuy]

The B-25 had a "normal total fuel load of 974 US gallons" (http://www.b25.net); a proportion of this would have been used already in the plane’s flight. By comparison, "it has been estimated that both UA Flight 175 and AA Flight 11 were carrying about 10,000 gallons of fuel when they impacted" (www.serendipity.li/wot/wtc_demolition_init.htm).

The jetliners also were carrying more than 100 times the fuel as well.

[Mikeanaro]

These two situations aren't entirely comparable.


So, let's do some more math.

http://www.csgnetwork.com/kineticenergycalc.html

B-25 at roughly median weight of 35,000 pounds. 747 at 274,000 pounds.

747 is 7.828571 times as massive.

230 mph is 102 meters per second
550 mph is 245 meters per second

For sake of simplicity call the bomber 1 kg, because we are comparing two objects.
1kg moving at 102 meters per second
2178 joules


An object 7.82 times as massive moving at 245 m/s
7.8kg moving at 245 meters per second
234097.5 joules

234097.5/2178 =107

The jetliner hit the building with more than 100 times the force that the B-25 did, and that is giving more mass and speed to the bomber than it probably had.

The jetliner had more fuel, more mass, and most importantly from a physics stand point, more speed.

Double the speed and the kinetic energy goes up by a factor of four.

This ignores differences in construction as well.

And one building was made in 1945 and the other in 1973, the one made in 1973 is bigger and better built and Im pretty sure they considered what happened in the empire state during the making... a 500 meter could face a plane someday, is a possibility.

An aluminum plane could be faster and yet because I hit a baseball 100 times faster against a wall it doesnt mean it will make a hole on it, so that theory doesnt work.

Also you said it was the fire the one that caused the collapse, but at the same time the empire state never collapsed but at least it should have partially collapse and that never happened either.

9/11 buildings were far away from collapsing and because of presto they fell like a card house with no physic cohesion at all, such a big thing would take ages to fall apart but no... in just a couple of hours there was nothing, the biggest staged ever.

[RandomGuy]

And one building was made in 1945 and the other in 1973, the one made in 1973 is bigger and better built and Im pretty sure they considered what happened in the empire state during the making... a 500 meter could face a plane someday, is a possibility.

An aluminum plane could be faster and yet because I hit a baseball 100 times faster against a wall it doesnt mean it will make a hole on it, so that theory doesnt work.

Also you said it was the fire the one that caused the collapse, but at the same time the empire state never collapsed but at least it should have partially collapse and that never happened either.

9/11 buildings were far away from collapsing and because of presto they fell like a card house with no physic cohesion at all, such a big thing would take ages to fall apart but no... in just a couple of hours there was nothing, the biggest staged ever.

http://www.debunk911myths.org/

http://www.jod911.com/


PE= m *9.8*413= 4073m

Mass is, by definition, simply a measurement of how much force a given amount of material will exert AT REST on an object that is resisting gravity.

SOOOO

The top floor would hit the ground with the same force as a 4073 story building, if that fall was unimpeded.

Now let's consider the fall of the top 30 stories.

They fell through the 3-5 floors of damaged sections and impacted the building below with some amount of force.

Let's call the distance accelerated as 3 floors and be generous. This is 11 meters.

Acceration of an object for 11 meters at 70% of gravity(dan's figure), would yeild an ending velocity of:

v^2= 2ad=2*9.8*.7*11=150=v^2, find the square root of 150, and bada bing, you get 12 meters per second

Subs ute this into the kinetic energy equation:
ke= 150*.5*m=ke=75m

This means the 30 floor section impacts the undamaged portion with the kinetic energy of SEVENTY FIVE TIMES ITS MASS.

Think about this for a moment.

The lower section of the building is designed to hold that 30 stories stationary plus a safety margin of 10 or 20%. So the maximum force that the underlying structure could apply to that falling section is 1.2 times its mass.

Further:
That falling section having as much kinetic energy as 75 times its mass means that it is effectively applying the same amount of force at the impact point that a 2270 story building would. if you held it stationary. (simple math: 30*75)
For the statement "the building would not have collapsed without explosives" implies that the building could have been TWENTY TWO TIMES TALLER THAN IT ACTUALLY WAS without collapsing.

STILL FURTHER

Your calculations seem to imply that the building structure below could absorb 30% of the falling energy.

IN JUST THE FIRST 11 METERS OF A 400 METER COLLAPSE THERE IS 62 TIMES THE AMOUNT OF FORCE REQUIRED TO COLLAPSE THE BUILDING.

Your assumption of about 1/3 the energy used to collapse the building is about 20 times what is reasonable. (1/62*20= 1/3) (more actually, if you consider the further distance and mass)

What happens, then when MORE mass is added AND accelerated?

Even if half the mass falls away or off to the side, there is still FAR more force and energy than would be needed to collapse the building WITHOUT ANY EXPLOSIVES.

[Pavlov]

OK Mikey -- walk us through your conspiracy. How were 1, 2 and 7 rigged to collapse?

[RandomGuy]

Damage = structural columns supporting more weight than they were designed for.

Fire = slowly weakening steel

More force + less ability to withstand that force. Once the load bearing capacity of any supporting element is exceeded, it collapses, meaning that even more weight is instantly distributed to already stressed, weakened parts.

Once you get movement of mass, KE equation kicks in again.

This is basic, simple physics, testable, reproducible.

[RandomGuy]

And one building was made in 1945 and the other in 1973, the one made in 1973 is bigger and better built and Im pretty sure they considered what happened in the empire state during the making... a 500 meter could face a plane someday, is a possibility.

An aluminum plane could be faster and yet because I hit a baseball 100 times faster against a wall it doesnt mean it will make a hole on it, so that theory doesnt work.

Also you said it was the fire the one that caused the collapse, but at the same time the empire state never collapsed but at least it should have partially collapse and that never happened either.

9/11 buildings were far away from collapsing and because of presto they fell like a card house with no physic cohesion at all, such a big thing would take ages to fall apart but no... in just a couple of hours there was nothing, the biggest staged ever.

Empire state building was shorter, with less damage, a smaller fire, and firefighting efforts that put the fire out.

Comparing the two events doesn't work at any level.