It appears and is more likely that the aluminum got a jump start. i.e. it melted and established it's burn before it even got to the iron.

Just playing devil's advocate here... But what melted the aluminum?

1000-1200 F it will melt.

---

Belief gets in the way of learning

It appears and is more likely that the aluminum got a jump start. i.e. it melted and established it's burn before it even got to the iron.

Just playing devil's advocate here... But what melted the aluminum?

WOOHOO!!! Someone else to play Devil's Advocate!!!! I don't have to think of all the questions to mess with people now!!!!!!!!!!!

By all means.....keep playing Devil's Advocate H.B. I need all the help I can get....lmao

---

Air Cold, the blade stops;
from silent stone,
Death is preordained

Calm Chaos Forums : Everyone Welcome

It appears and is more likely that the aluminum got a jump start. i.e. it melted and established it's burn before it even got to the iron.

Just playing devil's advocate here... But what melted the aluminum?

How fast was the aircraft moving when it hit the building? I believe that the impact released enough energy to vaporize the skin of the aircraft...instant finely divided aluminum powder.

Alledgedly around 450mph. Not hardly enough to vaporize any metal be it thick or thin. A 150 gr.bullet of lead and copper fired from a .30-06 rifle travels at about 3000 fps or about 2000 mph. When it hits a quarter inch steel plate it fragments but it doesn't vaporize. With a .45 Colt auto firing a bullet at a speed of maybe about 900 fps or about 600 mph against the same steel plate the bullet only flattens.

[edit]My husband was giving me this gun/bullet info.[/edit]

Contrary to popular belief, aluminum is not brittle but is really quite flexible.

It appears and is more likely that the aluminum got a jump start. i.e. it melted and established it's burn before it even got to the iron.

"Aluminum melts into burning 'goblet puddles' that would pool around depressions, [such as] beam joints, service openings in the floor, stair wells and so forth...The goblets are white hot, burning at an estimated 1800 degrees Celsius. At this temperature, the water of hydration in the concrete is vaporized and consumed by the aluminum. This evolves hydrogen gas that burns. Aluminum burning in concrete produces a calcium oxide/silicate slag covered by a white aluminum oxide ash, all of which serve to insulate and contain the aluminum puddle. This keeps the metal hot and burning.

It's likely that it started off slowly and reacted with other things first like in the concrete to gain it's burning temperature.

---

TEAM
LL

There are a number of variables for the ignition temperature of aluminum,
such as available oxygen concentration, gas pressure, catalysts/retarders
available etc.

The most important factor is the particle size. That is, a block of
aluminum is about impossible to get burning, even in pure oxygen. Have
you ever tried cutting aluminum with an oxyacetylene torch like they
do with iron? It is not successful. Aluminum forms a very tough layer of
refractive oxide on its surface and that layer prevents the otherwise
active metal from oxidizing further.

The situation is different, if the aluminum is a fine powder. In that
case, there is a very large surface area to be oxidized. If the grains
are small enough, the oxide layer may never reach its protective
thickness before all of the grain has been expended. Once the powder
is this fine, it really burns easily and fiercely and ignites well.
This can be demonstrated by throwing a spoonful of aluminum dust into
a hot flame (such as oxypropane or oxyacetylene torch). There will be
a tremendous flash and pulse of heat that is quite capable of burning
one's fingers and face (just in case someone tries it).

As for molten aluminum it is still very far from its ignition point.
There is really no danger of getting its vapor cloud to ignite.

How fast was the aircraft moving when it hit the building? I believe that the impact released enough energy to vaporize the skin of the aircraft...instant finely divided aluminum powder.

Hmmm...I am starting to get very confused here.

Either aluminum would burn enough to contirbute to the fires....or it wouldn't.

I know that aluminum CAN be welded, but I also know it takes a specialized type of welding machine to do so.

One thing that does strike me, speaking of aluminum, is that the flashes that were shown in the video looked like what would happen if you took aluminum dust and threw a bit of it into a fire.

NOT saying they did that. Just saw a resemblance in the type of flash.

---

Air Cold, the blade stops;
from silent stone,
Death is preordained

Calm Chaos Forums : Everyone Welcome

There are a number of variables for the ignition temperature of aluminum,
such as available oxygen concentration, gas pressure, catalysts/retarders
available etc.

The most important factor is the particle size. That is, a block of
aluminum is about impossible to get burning, even in pure oxygen. Have
you ever tried cutting aluminum with an oxyacetylene torch like they
do with iron? It is not successful. Aluminum forms a very tough layer of
refractive oxide on its surface and that layer prevents the otherwise
active metal from oxidizing further.

The situation is different, if the aluminum is a fine powder. In that
case, there is a very large surface area to be oxidized. If the grains
are small enough, the oxide layer may never reach its protective
thickness before all of the grain has been expended. Once the powder
is this fine, it really burns easily and fiercely and ignites well.
This can be demonstrated by throwing a spoonful of aluminum dust into
a hot flame (such as oxypropane or oxyacetylene torch). There will be
a tremendous flash and pulse of heat that is quite capable of burning
one's fingers and face (just in case someone tries it).

As for molten aluminum it is still very far from its ignition point.
There is really no danger of getting its vapor cloud to ignite.

My mistake about the fire not needing oxygen. That wasn't exactly what I meant, just came out wrong. Sorry all.

---

Air Cold, the blade stops;
from silent stone,
Death is preordained

Calm Chaos Forums : Everyone Welcome

Let me add to this.

....

Ok, so we have a very hot burning fire that doesn't need oxygen to continue burning. Sleestak mentioned thermite, and that sounds pretty reasonable considering how hot it burns. It would have caused a lot of damage.

....

It does need oxygen.

But it comes from the iron Fe2O3.

Thermite is a mixture of two materials, by weight 1 part Aluminum powder + (about) 3 parts Iron Oxide Fe2O3. Iron Oxide (Fe2O3 = rust) and aluminum metal powder undergo a reduction-oxidation reaction to form iron metal and aluminum oxide Al2O3:

Fe2O3(s) + 2 Al(s) --> Al2O3(s) + 2 Fe(l)

This reaction is so exothermic that the iron is actually molten!

But I hope you notice that everywhere that I've seen this reaction it involves Aluminum powder not chunks of material.

Powder simply increases the reaction rate because of the surface area available to react and is not inherent to the reaction occuring.

---

TEAM
LL

There are any number of aluminium products in an office building. Furniture frames, the grid that holds the ceiling tiles and lighting, many brands of office furniture, office equipment frames, etc.

Jeez... Some scientific minds we have here.

Aluminum, you want aluminum? How about quite a few tons that arrived with the plane?

That's why we have a plane expert here.

---

TEAM
LL

This
is a thermite reaction.
This
is video footage of the South Tower just before it collapsed.

Excellent. The smoke looks the same. The fiery sparks from molten metal looks the same. That video seems to show molten metal coming from the building.

Solid aluminum, when it gets hot enough, burns just like magnesium. Back in my Navy days, the USN built a class of cruisers which had aluminum superstructures. I was always amazed at such foolishness because one Exocet or Bullpup type missile and the ship will burn like a sun on the water.

This
is a thermite reaction.
This
is video footage of the South Tower just before it collapsed.

Excellent. The smoke looks the same. The fiery sparks from molten metal looks the same. That video seems to show molten metal coming from the building.

---

TEAM
LL

....

Ok, so we have a very hot burning fire that doesn't need oxygen to continue burning. Sleestak mentioned thermite, and that sounds pretty reasonable considering how hot it burns. It would have caused a lot of damage.

....

It does need oxygen. Thermite is a mixture of two materials, by weight 1 part Aluminum powder + (about) 3 parts Iron Oxide Fe2O3. Iron Oxide (Fe2O3 = rust) and aluminum metal powder undergo a reduction-oxidation reaction to form iron metal and aluminum oxide Al2O3:

Fe2O3(s) + 2 Al(s) --> Al2O3(s) + 2 Fe(l)

This reaction is so exothermic that the iron is actually molten!

But I hope you notice that everywhere that I've seen this reaction it involves Aluminum powder not chunks of material.

My biggest question is: Where did this Thermite come from?

Thermite is exactly what you posted. The iron comes from the steel and the aluminum come from any number of places in the office.

---

TEAM
LL

This
is a thermite reaction.
This
is video footage of the South Tower just before it collapsed.

---

....

Ok, so we have a very hot burning fire that doesn't need oxygen to continue burning. Sleestak mentioned thermite, and that sounds pretty reasonable considering how hot it burns. It would have caused a lot of damage.

....

It does need oxygen. Thermite is a mixture of two materials, by weight 1 part Aluminum powder + (about) 3 parts Iron Oxide Fe2O3. Iron Oxide (Fe2O3 = rust) and aluminum metal powder undergo a reduction-oxidation reaction to form iron metal and aluminum oxide Al2O3:

Fe2O3(s) + 2 Al(s) --> Al2O3(s) + 2 Fe(l)

This reaction is so exothermic that the iron is actually molten!

But I hope you notice that everywhere that I've seen this reaction it involves Aluminum powder not chunks of material.

My biggest question is: Where did this Thermite come from?

There are any number of aluminium products in an office building. Furniture frames, the grid that holds the ceiling tiles and lighting, many brands of office furniture, office equipment frames, etc.

Jeez... Some scientific minds we have here.

Aluminum, you want aluminum? How about quite a few tons that arrived with the plane?

Now that made me laugh. Somehow, in trying to explain why the buildings collapsed, someone apparantly FORGOT that a whole lot of the pieces from the planes themselves would have been made of aluminum.

Ok, so we have a very hot burning fire that doesn't need oxygen to continue burning. Sleestak mentioned thermite, and that sounds pretty reasonable considering how hot it burns. It would have caused a lot of damage.

As far as the asbestos insulation being removed, yes it was. The floor supports were coated in a fire retardant substance ( not sure what it was named ) but it was claimed that the substance was blown off the supports when the planes hit. When asbestos insulation is removed the normal procedure is to replace it with fiberglass insulation. I don't know if that was done in the towers or not.

---

Air Cold, the blade stops;
from silent stone,
Death is preordained

Calm Chaos Forums : Everyone Welcome

There are any number of aluminium products in an office building. Furniture frames, the grid that holds the ceiling tiles and lighting, many brands of office furniture, office equipment frames, etc.

Jeez... Some scientific minds we have here.

Aluminum, you want aluminum? How about quite a few tons that arrived with the plane?

The melting point of aluminum is 660 C Aluminum MSDSwhich seriously reduces the temperature required for possible catastropic failure.

The combinatin of aluminum and iron oxides is an exothermic reaction which means, it just gets hotter until it's done. At least up the boiling point of the lowest boiling metal. LOL

Although the reactants are stable at room temperature, when they are exposed to sufficient heat to ignite they burn with an extremely intense exothermic reaction. The products emerge as liquids due to the high temperatures reached (with iron (III) oxide, up to 2500°C (4500°F)— ...

Although, the ignition temperature is supposedly about 1200 C. The initial burn of Aluminum decribed in Scientific American might explain the initial gain in heat.

Thermite contains its own supply of oxygen, and does not require any external source such as air. Consequently, it cannot be smothered and may ignite in any environment, given sufficient initial heat.

Supplying it's own oxygen would explain why fires like this would continue buring under a big pile that is void of atmospheric oxygen. Many metals react with oxides to burn further.

---

TEAM
LL

JEEBIES!

I knew about thermite but I didn't really think the buildings had aluminum to combine with the iron oxide. Thermite is explosive at high temperatures I'm not sure where it was but it was there. Maybe the staircases? The thermal release could have a lot to do with compromising the structure.

from a scientific american article http://66.102.7.104/search?q=cache:GRC-t2wP49AJ:www.sciam.com/article.cfm%3FarticleID%3D000B7FEB-A88C-1C75-9B81809EC588EF21%26pageNumber%3D3%26catID%3D4+kerosene+fire+concrete+compromised&hl=en&lr=&strip=1]. If you can open it there are several pages.

"Aluminum melts into burning 'goblet puddles' that would pool around depressions, [such as] beam joints, service openings in the floor, stair wells and so forth...The goblets are white hot, burning at an estimated 1800 degrees Celsius. At this temperature, the water of hydration in the concrete is vaporized and consumed by the aluminum. This evolves hydrogen gas that burns. Aluminum burning in concrete produces a calcium oxide/silicate slag covered by a white aluminum oxide ash, all of which serve to insulate and contain the aluminum puddle. This keeps the metal hot and burning.

Here's some ammo, go wild.
And the thermal insulation had been removed previously. Which raises the question as to "why?" for the conspiracists

Some have raised questions about the degree of fire protection available to guard the structural steel. According to press reports, the original asbestos cementitious fireproofing applied to the steel framework of the north tower and the lower 30 stories of the south were removed after the 1993 terrorist truck bombing.

But for asbestos in 1986

(a) replacement of asbestos or of certain types of asbestos or products containing asbestos by other materials or products or the use of alternative technology, scientifically evaluated by the competent authority as harmless or less harmful, whenever this is possible;

(b) total or partial prohibition of the use of asbestos or of certain types of asbestos or products containing asbestos in certain work processes.

Various laws were past, so that might easily explain the removal of the abestos. Some laws were past essentially saying that if you had to work on it or demolish it, you had to remove it. After the initial damage, they may have been force to remove it. Or they decided to remove/replace for health/insurance reasons. It probably carried insuracne liabilities.

There are any number of aluminium products in an office building. Furniture frames, the grid that holds the ceiling tiles and lighting, many brands of office furniture, office equipment frames, etc.