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South Tower Collapse Video Frames

Video Evidence of the South Tower Collapse

The evidence showing of explosions in the South Tower is compelling. Here are frames from the South Tower collapse video taken from the east. Each frame is numbered by its position in the video. The video was shot at 30 frames per second. So an eight frame interval covers about one quarter of a second.

In frames above, we can see that the top 35 or so floors have broken off and are toppling southeastward. It is clear that that the top section itself must be disintegrating. Otherwise the top section would have extended far into parts of the building that are clearly as yet unaffected by the collapse.

But what could possibly cause the top section to disintegrate? And for that matter, what could possibly cause the top section to almost entirely disintegrate, before the lower section begins to collapse?

Most of the top section had not been affected by the aircraft strike or fires and was thus still the same immensely strong structure that had supported the building for more than 30 years. If this section was going to fall at all, it would fall as one piece, like a tree. Unless, of course, this section had been shattered by some as yet unaknowledged force such as explosives.

Frame 147 shows a row of explosives detonating right across the east face at the 79th floor.
Frame 203 shows a row of explosives detonating right across the east face at the 75th floor.

The middle photos show the dust from the explosions outlined in red.

The end photos show the relative positions of the two lines of dust.

It has been claimed that the explosions of dust that span the east face of the tower were caused by air being forced from the windows as each of the floors above collapsed. This explanation is obviously incorrect. If it was correct, such lines of dust would have been expelled from the windows of each floor in succession. That is, we would have seen such lines of dust expelled from floors 79, 78, 77, 76 and 75 in succession, but what we observe is an explosion of dust at floor 79, no new clouds of dust for a few floors, then another explosion of dust at floor 75. It is worth noting that the second line of (much larger) explosions occur at the center of a section of mechanical floors (the three mechanical floors appear as a slightly darker gray band across the building and are important for the strength they impart to the building). It is possible that the mechanical floors 76 and 75 (and also 74) have no windows, but of course, if this is so, it raises many more questions than it answers. In particular, if the mechanical floors have no windows, then the explosions of dust from floor 75 cannot be caused by air being forced from them as the floors above collapsed.

The dust due to the visible explosions is a whitish grey. The dust from the demolition of the upper section (which is disintegrating as it falls) is dark grey.

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