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Aluminum/magnesium Alloys

Bill Duke
post Jul 6 2008, 11:56 AM
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Hello...First time posting on this forum. Following, you will find a post from 7/6/08's CD article about WTC 7 and the new NIST report. Since I am not a metalurgist or a chemical engineer of any sort, I yield to anyone on this site who may have an eplanation. The contention is that the 747's body parts are composed of an aluminum/magnesium alloy that under conditions of proper combustion as in the crashes at the WTC, become highly flammable and reach temps of 4000 degrees. Here's the post....any feedback will be greatly appreciated...



Hi ~GDE~. I was an aircraft crash investigaor and worked directly for the SAC IG for five years. Crash investigations are always conducted when the cause of an aircraft crash is not known. There were very few pieces of aircraft left to investigate at the crash site of the WTC. Just a few scraps.

In addition, video evidence of exactly how the crashes occurred was readily available and there was no doubt as to the cause of the crashes.

Another person asked about melting steel, as burning jet fuel will not melt steel. That is true\, it will cause stteel to warp or bend out of shape after an hour of fire. What is also true is, aircraft aluminum is a mixture of aluminum and MAGNESIUM and it will burn at temps approaching 4,000 degrees, which is more than hot enough to melt steel beams.

The two aircraft were almost fully loaded with tons of fuel, which exploded on impact and the resulting fires were not accessable to firemen and auto sprinkers on those floors were wiped out by the crashes and they wouldnt have helped with a fuel and magnesium fire anyway. No firemen ever got onto the floors where the aircraft entered.

There were tons of smushed, into a compacted mass of burning aircraft, wedged right up into the buildings central cores. The heat would have been near 4,000 degrees at those locations. That is where the building floors were attached, and the heat went right up the center of the buildings, like giant chimneys.

There are also some other aircraft parts, such as the large landing gear wheels, which are solid magnesium, and once magnesium, or magnesium aluminum alloys are afire, they cannot be put out, except by burying them in sand or smothering with foam. Water on magnesium fires will cause it to explode.

Military aircraft generally have more magnesium than commercial airliners, but there was tons of magnesium in those 767s which struck the two towers. Later mdels ahve less magnesium. A fact which has been ignored in all of the official reports about the 9-11 disaster. It should not have been ignored.
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grizz
post Jul 6 2008, 01:29 PM
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Welcome to Pilots, Bill Duke!

QUOTE
No firemen ever got onto the floors where the aircraft entered.


This part, at least, is BS. A fire crew was about to put out the small fire in the South Tower when it was demolished.
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Bill Duke
post Jul 6 2008, 01:34 PM
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QUOTE (Oceans Flow @ Jul 6 2008, 12:29 PM) *
Welcome to Pilots, Bill Duke!



This part, at least, is BS. A fire crew was about to put out the small fire in the South Tower when it was demolished.


Absolutely true..and they have a recording of his saying that it was a small fire and would only take a couple of hoses to put it out. I'm pretty sure he died in the collapse.
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dMz
post Jul 6 2008, 01:34 PM
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Hello and welcome BD (we already have a Bill here),

One thing- most of us here are pretty "jaded" at this point due to months or years of dealing with online disinformation- we like to see a link to information that we can inspect firsthand. I detect a couple of indicators of "spin" and "appeal to 'expert' authority" in the above quoted information IMHO. There is a general statement about magnesium and aircraft alloys without any supporting sources of information...

According to:

http://www.ccohs.ca/oshanswers/chemicals/c...orking_alu.html

-----
"Reactive flammable solid. Bulk aluminum powder or dust in contact with water may heat spontaneously. Moist, finely divided aluminum powder may ignite in air, with the formation of flammable hydrogen gas. The hazard increases as the aluminum particle size decreases. Contact of burning aluminum with water forms flammable hydrogen gas, an extremely dangerous explosion hazard, particularly if the fire is in a confined area. Bulk aluminum metal itself is not combustible.

Under certain conditions, a dust cloud of aluminum powder can explode when ignited by a spark or flame. When evaluating the explosion hazard of a specific process or sample of material, the important factors to consider include: particle size and shape, dust concentration, the nature of any impurities, oxygen concentration, humidity, and extent of containment. Explosions of aluminum dusts have occurred in industry.

IGNITION SENSITIVITY: 1.4 (aluminum, atomized); 7.3 (aluminum, flake)

EXPLOSION SEVERITY: 7.7 (aluminum, atomized); 10.2 (aluminum, flake)

The EXPLOSIBILITY INDEX is greater than 10 for both atomized and flake aluminum. This value indicates that a "severe" explosion could occur. This hazard rating index is calculated by multiplying the ignition sensitivity (ignition temperature, concentration, etc.) and the explosion severity (explosion pressure, rate of pressure rise).

MINIMUM IGNITION TEMPERATURE: 650 deg C (1202 deg F) (cloud); 760 deg C (1400 deg F) (layer) (aluminum, atomized); 610 deg C (1130 deg F) (cloud); 320-326 deg C (608-619 deg F) (layer) (aluminum, flake); 420 deg C (788 deg F) (aluminum, 6 m)

MINIMUM CLOUD IGNITION ENERGY: 50 millijoules (mJ) (aluminum, atomized); 10 mJ (aluminum, flake); 13 mJ (aluminum, 6 m); 28 mJ (aluminum, 17 m)

MAXIMUM EXPLOSION PRESSURE: 579.2 kPa (84 psi) (aluminum, atomized); 875.7 kPa (127 psi or 8.8 bar) (aluminum, flake); 640 kPa (6.4 bar) (aluminum, 6 m); 700 kPa (7.0 bar) (aluminum, 17 m); 540 kPa (5.4 bar) (aluminum, 100 m)

MAXIMUM RATE OF PRESSURE RISE: Greater than 138000 kPa/sec (greater than 20000 psi/sec or 1380 bar/sec) (aluminum, atomized and flake); 133100 kPa/sec (1331 bar/sec) (aluminum, 6 m); 62100 kPa/sec (621 bar/sec) (aluminum, 17 m); 13500 kPa/sec (135 bar/sec) (aluminum, 100 m) "
-------
Unless this was a "finely powdered" or "atomized" Boeing 767-200, I don't afford much credibility to the "burning Al/Mg" theory. Also, I think aircraft are entirely irrelevant in discussions about WTC7, since it was never struck by aircraft.

Okay, on to Jet A fuel. There is a recent discussion here at:
http://pilotsfor911truth.org/forum//index....&p=10746044

The important part is "open air burning temperatures: 287.5 C (549.5 F)" for Jet A fuel. This is considerably lower than 420 C, so Jet A should not be able to ignite a cloud of 6 micro-meter aluminum "vapor" in a normally-aspirated fire (combustion or oxidation reaction).

Oh yes, I'm a scientist/engineer and am not exactly a stranger to metallurgy, materials science, chemistry, physics, etc.

Hope this helps,
d

EDIT: I think you and Oceans' are referring to the late Chief Orio Palmer.

http://www.wnyc.org/news/articles/7869
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richard cranium
post Jul 6 2008, 01:37 PM
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QUOTE (Oceans Flow @ Jul 4 2008, 03:29 PM) *
Welcome to Pilots, Bill Duke!



This part, at least, is BS. A fire crew was about to put out the small fire in the South Tower when it was demolished.



Yes,welcome Bill Duke. I agree with Oceans Flow. In one of the documentaries (I foget if it was Loose Change,s or the "Mysteries of 9/11") I remember hearing the tape of an actual firefighter who made it to one of the floors hit by a plane. In fact,he stated that the fires were not that intense and could be dealt with.
rc

ps. you didn't go to high school in southern california did you?
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dMz
post Jul 6 2008, 02:11 PM
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Hi again BD,

Although we have an unsourced generality about magnesium aircraft alloys, I looked up some information on Mg:

http://www.hss.energy.gov/NuclearSafety/te...1/hbk1081b.html

"MAGNESIUM

Properties

The ignition temperature of massive magnesium is very close to its melting point of 650 degrees C (1,202 degrees F). (See Table 2.) However, ignition of magnesium in certain forms may occur at temperatures well below 650 degrees C (1,200 degrees F). For example, magnesium ribbons and shavings can be ignited under certain conditions at about 510 degrees C (950 degrees F), and finely divided magnesium powder can ignite below 482 degrees C (900 degrees F).

Metal marketed under different trade names and commonly referred to as magnesium may be one of a large number of different alloys containing magnesium, but also significant percentages of aluminum, manganese, and zinc. Some of these alloys have ignition temperatures considerably lower than pure magnesium, and certain magnesium alloys will ignite at temperatures as low as 427 degrees C (800 degrees F). Flame temperatures of magnesium and magnesium alloys can reach 1,371 degrees C (2,500 degrees F), although flame height above the burning metal is usually less than 300 mm (12 in.).

As is the case with all combustible metals, the ease of ignition of magnesium depends upon its size and shape. As noted earlier, the specific area of a combustible substance is the surface area of the substance exposed to an oxidizing atmosphere per gram of the substance and is usually expressed in cm{sup 2}/g. A combustible substance that has a high specific area is more prone to oxidize, heat, and ignite spontaneously. Thin, small pieces, such as ribbons, chips, and shavings, may be ignited by a match flame whereas castings and other large pieces are difficult to ignite even with a torch because of the high thermal conductivity of the metal. In order to ignite a large piece of magnesium, it is usually necessary to raise the entire piece to the ignition temperature. "

Table 2:
http://www.hss.energy.gov/NuclearSafety/te...1/1081tab2.html

More on magnesium (but some info here looks questionable IMHO):
http://www.magnesium.com/w3/forum/read.php?thread=4292

EDIT: Also, officially there were no Boeing 747s involved in the events of 9/11 (unless you count E4B's and the USAF 84 RADES cover letter).

EDIT2: Here's the PDF format of this DOE document for download:
http://www.hss.energy.gov/NuclearSafety/te...81/hdbk1081.pdf
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Bill Duke
post Jul 6 2008, 02:52 PM
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QUOTE (dMole @ Jul 6 2008, 12:34 PM) *
Hello and welcome BD (we already have a Bill here),

One thing- most of us here are pretty "jaded" at this point due to months or years of dealing with online disinformation- we like to see a link to information that we can inspect firsthand. I detect a couple of indicators of "spin" and "appeal to 'expert' authority" in the above quoted information IMHO. There is a general statement about magnesium and aircraft alloys without any supporting sources of information...

According to:

http://www.ccohs.ca/oshanswers/chemicals/c...orking_alu.html

-----
"Reactive flammable solid. Bulk aluminum powder or dust in contact with water may heat spontaneously. Moist, finely divided aluminum powder may ignite in air, with the formation of flammable hydrogen gas. The hazard increases as the aluminum particle size decreases. Contact of burning aluminum with water forms flammable hydrogen gas, an extremely dangerous explosion hazard, particularly if the fire is in a confined area. Bulk aluminum metal itself is not combustible.

Under certain conditions, a dust cloud of aluminum powder can explode when ignited by a spark or flame. When evaluating the explosion hazard of a specific process or sample of material, the important factors to consider include: particle size and shape, dust concentration, the nature of any impurities, oxygen concentration, humidity, and extent of containment. Explosions of aluminum dusts have occurred in industry.

IGNITION SENSITIVITY: 1.4 (aluminum, atomized); 7.3 (aluminum, flake)

EXPLOSION SEVERITY: 7.7 (aluminum, atomized); 10.2 (aluminum, flake)

The EXPLOSIBILITY INDEX is greater than 10 for both atomized and flake aluminum. This value indicates that a "severe" explosion could occur. This hazard rating index is calculated by multiplying the ignition sensitivity (ignition temperature, concentration, etc.) and the explosion severity (explosion pressure, rate of pressure rise).

MINIMUM IGNITION TEMPERATURE: 650 deg C (1202 deg F) (cloud); 760 deg C (1400 deg F) (layer) (aluminum, atomized); 610 deg C (1130 deg F) (cloud); 320-326 deg C (608-619 deg F) (layer) (aluminum, flake); 420 deg C (788 deg F) (aluminum, 6 m)

MINIMUM CLOUD IGNITION ENERGY: 50 millijoules (mJ) (aluminum, atomized); 10 mJ (aluminum, flake); 13 mJ (aluminum, 6 m); 28 mJ (aluminum, 17 m)

MAXIMUM EXPLOSION PRESSURE: 579.2 kPa (84 psi) (aluminum, atomized); 875.7 kPa (127 psi or 8.8 bar) (aluminum, flake); 640 kPa (6.4 bar) (aluminum, 6 m); 700 kPa (7.0 bar) (aluminum, 17 m); 540 kPa (5.4 bar) (aluminum, 100 m)

MAXIMUM RATE OF PRESSURE RISE: Greater than 138000 kPa/sec (greater than 20000 psi/sec or 1380 bar/sec) (aluminum, atomized and flake); 133100 kPa/sec (1331 bar/sec) (aluminum, 6 m); 62100 kPa/sec (621 bar/sec) (aluminum, 17 m); 13500 kPa/sec (135 bar/sec) (aluminum, 100 m) "
-------
Unless this was a "finely powdered" or "atomized" Boeing 767-200, I don't afford much credibility to the "burning Al/Mg" theory. Also, I think aircraft are entirely irrelevant in discussions about WTC7, since it was never struck by aircraft.

Okay, on to Jet A fuel. There is a recent discussion here at:
http://pilotsfor911truth.org/forum//index....&p=10746044

The important part is "open air burning temperatures: 287.5 C (549.5 F)" for Jet A fuel. This is considerably lower than 420 C, so Jet A should not be able to ignite a cloud of 6 micro-meter aluminum "vapor" in a normally-aspirated fire (combustion or oxidation reaction).

Oh yes, I'm a scientist/engineer and am not exactly a stranger to metallurgy, materials science, chemistry, physics, etc.

Hope this helps,
d

EDIT: I think you and Oceans' are referring to the late Chief Orio Palmer.

http://www.wnyc.org/news/articles/7869


Thank you for this wealth of information.

So, as a layman/non-engineer type of being, allow me to interpret this info and ask you if I am at all close to anything resembling sense.

For the material in these planes...I would say, mainly the bodies of the planes themselves....to ignite as the result of a fire from the diesel fuel, the particles of the alloy would have to be exremely small...probably powdery. And if they could ignite at all, it would take a temperature almost double the temperature of the burning diesel fuel. What other source could possibly ignite these almost powdery particles other than the fuel itself? AND, could they reach a temperature high enough to melt those huge steel girders.....OR even bend them? Could the temps possibly cause the titanium engines to vaporize?
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grizz
post Jul 6 2008, 03:02 PM
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I have a question, dMole. What kind of density of the aluminum dust would be required for ignition? IOW, parts per billion.
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dMz
post Jul 6 2008, 03:22 PM
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QUOTE (Oceans Flow @ Jul 6 2008, 01:02 PM) *
I have a question, dMole. What kind of density of the aluminum dust would be required for ignition? IOW, parts per billion.

I'd need to look in some references on explosives (that's not commonly public information for obvious reasons). Have you ever been inside a feed store or roller mill? That dust is approximately as explosive as propane (which will run an internal combustion engine quite well at low and moderate altitudes).

http://www.cvtechnology.com/Dust-Explosion.htm

You would likely need aluminum particulate in the micro-meter (10^-6 meter) range from grinding or sanding. Think of dust that "hangs" in the air, like on a dirt road or pollen.

As far as the parts per billion, I don't really know, but I would assume that a "cloud" of aluminum dust "hanging" in the air could be flammable at about 400 C (which is still a little out of reach of a household range on "broil").
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tnemelckram
post Jul 6 2008, 03:24 PM
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HI Bill Duke and thanks dMole!

Mr. "Aircraft crash investigaor and worked directly for the SAC IG for five years" says that magnesium burns at 4000F.

QUOTE
What is also true is, aircraft aluminum is a mixture of aluminum and MAGNESIUM and it will burn at temps approaching 4,000 degrees, which is more than hot enough to melt steel beams.

. . . . . . . . . .

There were tons of smushed, into a compacted mass of burning aircraft, wedged right up into the buildings central cores. The heat would have been near 4,000 degrees at those locations. That is where the building floors were attached, and the heat went right up the center of the buildings, like giant chimneys.


According to dMole's link to the DOE regarding magnesium and its alloys, the burning temp is 2500F:
QUOTE
Flame temperatures of magnesium and magnesium alloys can reach 1,371 degrees C (2,500 degrees F), although flame height above the burning metal is usually less than 300 mm (12 in.).


So the guy is grabbing an extra 1500F right off the top.

In addition, the flame height is only 12 inches. That would seem to limit the updraft effect that he makes much of - "The heat went right up the center of the buildings, like giant chimneys".

Finally you would think that NIST would have seized upon this to bolster their conclusions, but this is not in their report.
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dMz
post Jul 6 2008, 03:33 PM
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QUOTE (Bill Duke @ Jul 6 2008, 12:52 PM) *
So, as a layman/non-engineer type of being, allow me to interpret this info and ask you if I am at all close to anything resembling sense.

For the material in these planes...I would say, mainly the bodies of the planes themselves....to ignite as the result of a fire from the diesel fuel, the particles of the alloy would have to be exremely small...probably powdery. And if they could ignite at all, it would take a temperature almost double the temperature of the burning diesel fuel. What other source could possibly ignite these almost powdery particles other than the fuel itself? AND, could they reach a temperature high enough to melt those huge steel girders.....OR even bend them? Could the temps possibly cause the titanium engines to vaporize?

I'd say you are right on track BD (especially with regards to structural steel girders). I doubt anyone here really wants to get into a discussion about heat transfer mechanisms and thermal conductivity, but those are key concepts in the WTC questions. I believe that the turbofan jet engines are mostly high-temperature steel alloys, but there is some titanium in there somewhere I'm sure (but I'm not a jet engine guy per se). And I'd say there isn't a snowball's chance in Hell that the engines would vaporize in ANY fire short of a Class Delta plasma fire (and that usually only happens in nuclear reactors or in thermonuclear weapons).

On the magnesium/aluminum question, here are the common aerospace alloys (with magnesium percentages), but I don't have any official Boeing specs and you aren't likely to find any unless you know someone who works for Boeing.

http://en.wikipedia.org/wiki/Aluminium_alloy

http://www.unitedaluminum.com/aluminum-spe...s-reference.php
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dMz
post Jul 6 2008, 03:47 PM
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QUOTE (tnemelckram @ Jul 6 2008, 01:24 PM) *
Mr. "Aircraft crash investigaor and worked directly for the SAC IG for five years" says that magnesium burns at 4000F.

Thank you TN,

I glossed over those acronymns (I've seen too many in my life). I'll assume this is the USAF Strategic Air Command Inspector General as my first guess.

That's pretty damn "brassy" high-up, DoD "official government" theory if you ask me. yes1.gif
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dMz
post Jul 6 2008, 04:08 PM
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Also from that Wiki aluminum alloy link above:

"Aluminium's intolerance to high temperatures has not precluded its use in rocketry; even for use in constructing combustion chambers where gases can reach 3500 K. The Agena upper stage engine used a regeneratively cooled aluminium design for some parts of the nozzle, including the thermally critical throat region; in fact the extremely high thermal conductivity of aluminium prevented the throat from reaching the melting point even under massive heat flux, resulting in a reliable lightweight component."

3500 K is 3226.85 C or 5840.33 F
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dMz
post Jul 6 2008, 04:14 PM
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QUOTE (Bill Duke @ Jul 6 2008, 12:52 PM) *
And if they could ignite at all, it would take a temperature almost double the temperature of the burning diesel fuel. What other source could possibly ignite these almost powdery particles other than the fuel itself?

Just to be technically correct, we should call that "Diesel No. 1" or kerosene or Jet A or Jet A-1 or JP8. That is all. wink.gif

EDIT: Related to AA77 Pentagon wheel hub thread:
http://pilotsfor911truth.org/forum//index....&p=10738979
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Bill Duke
post Jul 6 2008, 06:39 PM
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QUOTE (tnemelckram @ Jul 6 2008, 02:24 PM) *
HI Bill Duke and thanks dMole!

Mr. "Aircraft crash investigaor and worked directly for the SAC IG for five years" says that magnesium burns at 4000F.



According to dMole's link to the DOE regarding magnesium and its alloys, the burning temp is 2500F:


So the guy is grabbing an extra 1500F right off the top.

In addition, the flame height is only 12 inches. That would seem to limit the updraft effect that he makes much of - "The heat went right up the center of the buildings, like giant chimneys".

Finally you would think that NIST would have seized upon this to bolster their conclusions, but this is not in their report.


Continued thanks for the info. This gentleman still insists that the burning temp of magnesium and alloys is over 4000F. Can you provide me with that DOE link to substantiate the 2500F? Can't seem to find it on dMole's message.
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tnemelckram
post Jul 6 2008, 06:46 PM
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Duke:

Link is in dMole's post No. 6 above if the following does not work:

http://www.hss.energy.gov/NuclearSafety/te...1/hbk1081b.html
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dMz
post Jul 6 2008, 07:05 PM
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Hi BD,

Post #6, but here it is again:

http://www.hss.energy.gov/NuclearSafety/te...1/hbk1081b.html

Also, I added the .PDF of the same (but you'll need to search for "magnesium" in that):
http://www.hss.energy.gov/NuclearSafety/te...81/hdbk1081.pdf

Did this joker provide a link for the 4000F figure or mention a specific aluminum/magnesium alloy by number?
[EDIT: He appears to be using Wikipedia here:
http://en.wikipedia.org/wiki/Magnesium

"Incendiary use: Magnesium is flammable, burning at a temperature of approximately 2500 K (2200 C, 4000 F), and the autoignition temperature of magnesium is approximately 744 K (473 C, 883 F) in air. The extremely high temperature at which magnesium burns makes it a handy tool for starting emergency fires during outdoor recreation. Other related uses include flashlight photography, flares, pyrotechnics, fireworks sparklers, and incendiary bombs."]

Wikipedia information is highly "suspect" in many areas...
-------------------

Here are more magnesium burning temperature links (but I don't see any agreement here):

1982 C
http://www.emedicine.com/emerg/byname/cbrn...nd-thermite.htm

"up to 2400 C"
http://www2.uni-siegen.de/~pci/versuche/english/v44-3.html

2800 C
http://www.madsci.org/posts/archives/2001-...75694.Ch.r.html

------------------------
1335 C
http://www.chem.leeds.ac.uk/delights/texts/expt_20.html

Aha! There appears to be a discrepancy in the "color temperature" of Mg and in the actual temperature of the combustion reaction above:

"According to Rogers [2] the temperature of a magnesium flame is 1335oC At a high temperature magnesia has a very high emissive power for light [3-5]; the light is not very different from that of burning magnesium. Drummond [6] tried magnesia in place of lime for the lime-light, but found the intensity of its illumination to be less than half that of lime. E.L. Nichols [7] found that the colour temperature of incandescent magnesia is 5000 oC, while the actual temperature is not over 2000 degrees."
-----------------
References.

1. J.W. Mellor, A Comprehensive Treatise on Inorganic and Theoretical Chemistry, vol. 4, new impr., London, Longman, Green and Co., 1957, p. 286.

2. F.J. Rogers, Amer. J. Science, Ser. 3, 1892, 43, 301.

3. D. Brewster, Edin. J. Science, 1820, 3, 343.

4. H. Caron, Compt. Rend., 1868, 66, 850.

5. C.M.T. du Motay and C.R.M. de Marechal, Bull. Soc. Chim., Ser. 2, 1868, 10, 318.

6. T. Drummond, Edin. J. Science, 1826, 5, 319.

7. E.L. Nichols, Trans. Amer. Illum. Eng. Soc., 1929, 16, 331.

EDIT: 1335 C is 2435 F. I'm leaning towards the original DOE numbers around 2500 F right now in absence of better references.
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dMz
post Jul 6 2008, 07:21 PM
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The combustion temperature of magnesium is clearly a red herring from what I found above. Has the "expert" provided a verifiable source for what exact alloy was used in the aircraft in question and provided documentable links to the combustion properties of said alloy? Short of independently-verifiable information, this is just "handwaving" rhetoric.

http://www.nizkor.org/features/fallacies/red-herring.html

If this guy is claiming Boeing 747, he is not well versed in the "official" Boxcutter Conspiracy Theory (OBCT). I've got the serial numbers and engine types of all 4 alleged aircraft in question if you need me to look those up, too. The FAA keeps pretty good records on commercial aircraft- each aircraft is supposed to have an "N" number on its tail.
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Bill Duke
post Jul 6 2008, 07:54 PM
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QUOTE (dMole @ Jul 6 2008, 06:21 PM) *
The combustion temperature of magnesium is clearly a red herring from what I found above. Has the "expert" provided a verifiable source for what exact alloy was used in the aircraft in question and provided documentable links to the combustion properties of said alloy? Short of independently-verifiable information, this is just "handwaving" rhetoric.

http://www.nizkor.org/features/fallacies/red-herring.html

If this guy is claiming Boeing 747, he is not well versed in the "official" Boxcutter Conspiracy Theory (OBCT). I've got the serial numbers and engine types of all 4 alleged aircraft in question if you need me to look those up, too. The FAA keeps pretty good records on commercial aircraft- each aircraft is supposed to have an "N" number on its tail.


dMole.....I presented him with those figures from the DOE link. We'll have to see what he does with those. He presents himself with an attitude similar to Faux TV commentators and uses similar tactics to scare off his opponents. He's a plant or just someone with an immense ego who does NOT enjoy being wrong. I'll choose the latter, since I know he has been posting on CommonDreams.org for years. He has referred fellow posters to this link...

http://www.geoffmetcalf.com/pentagon/pentagon_20020316.html

which presents a good collection of "official photos"...body parts...aircraft parts......etc...etc...Personally, until and IF I see those videos the FBI has confiscated, I intend to question any photos or evidence that could very easily have been planted. WHY was it removed so quickly? As I said in my last post on CD today, any criminal scene as such would have been cordoned off, diagrammed, photographed and examined for weeks, if not months.
The place was sterile in a matter of hours, was it not?

Anyway, my continued appreciation for your assistance. If you wish, you can check out the entire article and thread (now over 200 comments).

9/11 always brings out a plethora of comments. The longest thread I have witnessed to date was on ICH a few years ago...over 950 comments..Citizens are simply searching for the truth.

Thanks again, BD...
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lunk
post Jul 6 2008, 09:42 PM
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Hello, and welcome to the forums.

I found an interesting article about Magnalium:

http://en.wikipedia.org/wiki/Magnalium#Uses,

(edit) quote added
"Although they are generally more expensive than aluminium, the high strength, low density, and greater workability of alloys with low amounts of magnesium leads to their use in aircraft[2] and automobile parts. Alloys with about 50% magnesium are brittle and corrode easily, which makes them unsuitable for most engineering uses. However, these alloys are flammable when powdered, are more resistant to corrosion than pure magnesium, and are more reactive than pure aluminium and are therefore used in pyrotechnics as a metal fuel and to produce sparks."

I didn't know about its' use in pyrotechnics as well as aircraft skins.

cheers, lunk

This post has been edited by lunk: Jul 6 2008, 09:44 PM
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