Arthur,

About the column bolt-access-holes only being every third tree on a floor, yes, I know that.

To heat-weaken - for example - perimeter columns along one face, three floors would be involved.

(Incidentally, it's good to remember that the 3-storey panels spanned 4 floors.)


About the column bolt-access-holes being covered by fire protection and decorative facades - well at least they are not welded shut, as some have argued.

My model does require some - by hardly overwhelming - "work" to be done.

And that "work" would be in office spaces.


To your points about the column bolt-access-holes' positions relative to gussets - you are confusing a couple of ideas, so allow me to untangle them.

Thermite planted inside box columns would be to heat the column bolts, or a small cross-section of the column. Thermite planted inside box columns would not be for affecting the dampers.

Thermite planted at the gusset seats - wrapped in paper and black plastic - and in an amount that would only heat the gusset, but ignite the damper - is what accounts for the 7 major smoke releases from WTC2, all 1 minute long +/- a few seconds. (See NCSTAR 1-5A/9/C, page 409 (nominal), table 9.4)

The serial ignition of the planted thermite by thermite fuse accounts for the "coordinated smoke puffs reminiscent of old fashioned steam driven pipe organs" as described in the same report. Note that the report says that these phenomena (and others) are correlated.

My model explains these phenomena better than NIST's model

NIST says the major smoke releases are burning pools of jet fuel (all perfectly equally sized for your convenience).

NIST has no explanation for who's playing the steam driven pipe organ.

NIST's...inadequacies...become more apparent if you actually READ the report.


WRT spandrel splice gaps and the little 1" access holes. Well, you can almost see them in your photo, but unfortunately the splice plates are not bolted down yet.

For photos, see this link (If you read the text, please note that much has changed over time. I am presenting this link for the photos.)


In these photos you can see that:

- Spandrels did not touch, but rather, had a gap between them;

- Spandrel splice plates sandwiched the gap, and created a slender vertical tube;

- Spandrel splice plates are shorter than the spandrels are wide;

- This creates a small hole, through which the spandrel splice gap "tube" could be filled with thermite.


On to the trusses: you picked the perfect image!!!

For other readers, look at the RH image. Look between the words "gusset" and "Section X-X". Do you see how two top chords juxtapose to create a rectangular tube?

Thermite was planted in the "tubes," wrapped in paper and black plastic. (Note that the black plastic burning helps mask the white aluminum oxide. Thermite at gussets was masked by the black smoke from the dampers, and the black plastic wrap.

See this post for a discussion of NIST recovered steel member N8, which reveals NIST's one necessary exposure of evidence of planted thermite, and thermite fuse (previously called thermite-dusted shock-tube).

Arthur, the thermite planted at truss top chords was not intended to make the floors disconnect from the spandrels, but rather, would help the floors to sag near the spandrel.

WRT dampers, I know they are not load bearing. But NIST says, and Neu-Fonze agreed (if I understood him correctly) that compromised dampers destabilized the floor membranes.

I suspect if the top chords were heated, the floors would be more prone to sagging if the dampers were burned away first.

By the way, the burning of thermite at gussets, and the burning of dampers as a consequence, sure fits NIST's observations of fires along the tops of windows. That might be better phrased as at the bottom of spandrels!

Max