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9-11 Archive 2006

Open Letter to NIST Investigators

May 26, 2006

9-11 WTC Team at NIST

National Institute of Standards and Technology

U.S. Dept. of Commerce

With great interest I read the comments in the Final Report about the unexplained molten metal, pressure pulses, and puffs of smoke observed in the South Tower (WTC 2) shortly before it collapsed. The discussion of the molten metal and pressure pulses in the NIST report (Appendix NCSTAR 1-5A, Chapter 9, "Fire Behavior in WTC 2) raises more questions than it answers.

MOLTEN METAL IS NOT ALUMINUM

The composition of the unknown molten metal is discussed:

"The composition of the flowing material can only be the subject of speculation, but its behavior suggests it could have been molten aluminum." (p. 375)

Having seen molten aluminum at the temperature suggested by the NIST report, i.e. about 650 degrees Celsius, I learned that molten aluminum appears silvery-gray in daylight. In fact it appears to have the same color as aluminum foil due to its low emissivity in daylight conditions. The flowing molten metal coming from the eastern corner of the 81st floor of WTC 2, however, appears distinctly yellow or bright orange in the daylight and when it breaks up, it appears white. Therefore, the photographic evidence proves that this molten metal cannot be aluminum.

What is it about the behavior of this molten metal that "suggests it could have been aluminum," as the NIST authors wrote? The "molten metal" seen spilling from the WTC 2 is mentioned 27 times in this appendix alone and it is usually accompanied by a phrase "assumed to be aluminum." Elsewhere it is described as "possibly aluminum," and sometimes, simply as "molten aluminum." (e.g. pp. 412-413) How can the WTC scientists at NIST assume for one minute that this molten metal is aluminum?

Is it not, in fact, much more likely that this is molten iron? The color of the molten metal falling from the 81st floor of the WTC 2 suggests that the metal is NOT aluminum but is more likely to be iron. Molten aluminum appears silvery-gray in daylight conditions, as professor Steven E. Jones of Brigham Young University wrote in his paper "Why Indeed Did the WTC Buildings Collapse?"

The approximate temperature of a hot metal is given by its color, quite independent of the composition of the metal. (A notable exception is aluminum, which due to low emissivity and high reflectivity appears silvery-gray in daylight conditions, at all temperatures whether in solid or liquid forms. Aluminum does incandesce like other metals, but faintly, so that in broad daylight conditions in air, it appears silvery-gray according to experiments done at BYU. [Jones, 2006])

In his paper "Experiments with Molten Aluminum," Jones wrote that the use of Thermite, or a derivative such as Thermate, is consistent with the observation of yellow-white hot molten metal observed falling from the northeast corner of WTC 2 (the South Tower) prior to its collapse.

We note that aluminum has many free electrons, so it reflects ambient light very well and it appears silvery. Aluminum at about 1000 C will emit yellow light (incandescence) the same as iron, but in daylight the molten aluminum would appear silvery due to high reflectivity combined with low emissivity, while molten iron would appear yellow (as seen in the video record.) Moreover, aluminum from a plane would melt at approximately 550-650 C, and would flow away from the heat source, and thus would be very unlikely to reach 1000 C at all. Thus, the observed molten metal flowing from WTC 2 on 9-11 cannot be aluminum but could be molten iron from the Thermite reaction.

THE UNEXPLAINED "PRESSURE PULSES"

Furthermore, the pressure pulses and puffs of smoke, which the report says accompanied the flows of molten metal, strongly suggest that some sort of explosive reaction was causing the pressure pulses and the molten metal. Pressure pulses are mentioned 48 times in this appendix (NCSTAR 1-5A) alone. (The words "explosion" or "explosive" are not mentioned once although scores of eyewitnesses reported hearing and seeing explosions before the tower fell.)

NIST says that the cause of these pressure pulses is "unknown": "The sources for the pressure pulses that created the wide-spread smoke and/or dust puffs observed on multiple faces of WTC 2 are unknown." It also says that these "pressure pulses" and releases of puffs of smoke "were correlated with releases of molten aluminum." (p. 412)

"The puff of smoke and/or dust just prior to the first appearance of the molten material suggests that the ultimate event responsible for the release of the material occurred suddenly, in the process creating a pressure pulse that forced smoke and/or dust out of open windows over three floors." (p. 375)

"the flows of molten metal were temporally correlated with pressure pulses" (p. 396)

"At 9:57:32 there was a fairly intense pressure pulse within the tower. The flow rate of molten metal increased dramatically at this time." (p. 383)

The "pressure pulses" that preceded the massive flow of molten metal seen in this photo (Fig. 9-75) are described by NIST on page 380:

"At 9:53:41 and 9:53:46 a.m. two pressure pulses forced additional smoke from windows on the north face. Both of these occurrences were accompanied by short flows of molten material from the same window, 80-255, on the 80th floor observed earlier. The largest flow occurred during the second release. Figure 9-75 shows a view of the northeast corner of WTC 2 taken from a video at 9:53:51 a.m. The bright molten stream flowing from the top of window 80-255 is prominent."

As we can see from the photographs, these puffs of smoke were whitish, suggesting that they were caused by an explosive reaction like Thermite. In Fig. 9-71, the reaction that is producing the molten metal is seen to be producing a large amount of white smoke. This is evidence of a Thermite reaction is progress.

Taking these observations together, the evidence indicates that something like Super-Thermite (fine particles of aluminum and iron oxide) appears to have been used on the 81st floor of the WTC and could be responsible for the extreme heat, the pressure pulses, the molten iron flows, and the white puffs of smoke. The Thermite was evidently used to cut the core columns and initiate the collapse of the tower.

Is this not the best explanation for the evidence we see from the 81st floor and the massive flow of molten metal? This same corner of the building was the location of the hottest "hot spot" that persisted for weeks beneath the rubble.

WHO OCCUPIED FLOORS 81 AND 82?

Because the molten metal apparently formed on the 81st floor of the WTC 2, there is a need to understand exactly what was on that floor on 9-11.

Table 5-3 provides information about the conditions of the floors 79, 81, and 82 in the South Tower (WTC 2). This information is on page 79 of the NIST Final Report. Fuji Bank was the tenant of these floors but in the column of the General Description of Tenant Layout there are empty spaces for these three floors. Is that because they were empty? Were they not being used by Fuji Bank employees at the time? Is that why there is no description what was on these floors?