Update on the Pentagon's Support Columns thought by some to disqualify a 757
Adam Larson/Caustic Logic
The Frustrating Fraud
Last updated 9/10/07 mid-day
According to the ASCE's Pentagon Building Performance Report, “the original structural system" of the Pentagon "was entirely cast-in-place reinforced concrete using normal-weight aggregate."  This means the frame, comprised of columns supporting and connected to beams, girders, and floor slabs. The report illustrated "the typical members" in the impact area (left). The reinforcements in these columns are vertical bars, typically six, wrapped with a welded rebar that spirals from top to bottom. This cage is filled and covered with concrete, all told measuring 21” square.  These were evenly spaced at intervals of roughly ten feet (I'm not sure exactly).
As seen above, many impacted columns inside the building exhibited a pronounced inward bend, what seems to be a bowing by Boeing. At least one column on the outer wall seems to bear this mark: Column 9aa - warped by the left wing"
Assessing initial, pre-collapse damage to support columns is problematic; after the impacted section collapsed about twenty minutes after the 757 attack, the initial plane imprint was invisible beneath a heap of masonry, with only a few published photographs taken of the in that window of time. There was little if any video of the elusive original wound, and of course no up-close studies conducted. While most of the photos are of the best quality, it was still a violent and chaotic scene and a little hard to read, but often all investigators, even official ones, had to go on.
In assessing a “hole,” we can talk about superficial damage like removal of the building’s limestone façade and windows, and structural damage to the building’s frame and support columns. Missing outer wall and windows are generally agreed on when addressed on both sides of the debate – this is all evident. But not everybody agrees on the state of the columns in the 757’s alleged flight path.
For example, take the roughly 16 foot wide "hole" apparent on the second floor; the ASCE reported "on the second floor, the facade was missing between column lines 11 and 15. However, windows and their reinforcing frames were still in place between column lines 11 and 13," thus leaving the impression of less damage there.  One photo I've seen shows what seems to be a column running down the middle of that hole where 14 would be - but all other shots show no column in that spot. Through the magic of selectivity, many 9/11 Truthers have found this pillar intact and sound and concluded no plane fuselage entered there.
- Why they're wrong. Columna 14AA: The Smoking Gun That Fell Away?
But the main question with the state of the supports is on the first floor; above is one of the few shots of the first floor showing clearly the impact point and the right (south) half of the damaged area where the plane hit. Note the orange of fires is here prevalent on the second floor and almost absent from the first. This is consistent with the high impact of the fuselage breaching the floor slab and sending exploding jet fuel into both floors, and the reported banking angle of the plane, with starboard wing tipped high and cutting across the second floor slab. Just beneath that and just to the right of main impact, is what would have to be the entry “hole” for the 757’s right engine and wing root. In that spot, most all sources on both sides agree, there are three exterior columns there, 15-17AA, that are badly damaged and warped (the picture above is from the ASCE’s Performance Report). Opinions differ as to whether or not that’s odd, and what it means for the 757 impact story.
- I disagree with nearly everyone here, and this post explains why. This graphic sums it up somewhat:
One clue there’s a problem with identifying just what was a column in this area is the discrepancy even between official reports, explained in this Split-off sub-post:
Confusion in Reports: 15-18 missing, present, or a bit of both?
If these three mystery slants are indeed something other than columns 15-17, then we are left with a roughly 90 foot-wide area in which all supports were obliterated on the ground floor, front line - leaving plenty of room for the engine-fuselage-engine penetrating core of a 757, whose deeper but less even damage further in would explain the collapse of everything above that twenty minutes later.
Additional column damage deeper in the building will be covered in another forthcoming post, and will also be touched on briefly in an upcoming post on the “Punch-out” hole.