Building 7's Implosion
At 5:20 PM, on 9/11/01, the angular facade of
Building 7 went limp,
and the building fell straight down into a cloud of dust.
Since the building had been evacuated much earlier,
the collapse is not thought to have killed anyone.
The resemblance of Building 7's collapse to a textbook,
controlled demolition is clearly evident in videos of the event.
The following three videos can be viewed on
a site devoted to investigating the collapse of Building 7.
This 36-second video shows Building 7 from a distant northeast vantage point.
This 9-second video shows Building 7 from about a mile to the northeast on West Broadway.
This 9.6-second video shows Building 7 from about 1000 feet to the north.
All of the videos and images show Building 7 collapsing
in a smooth vertical motion.
Timing of the first and second videos above reveals
that the entire collapse took only 6.5 seconds,
ignoring the collapse of the east penthouse,
which occurred a few seconds before the main event.
After its precipitous collapse, all that was left of the 47-story
skyscraper was a tidy pile of rubble lying almost entirely
with the building's footprint.
What Caused Building 7 to Implode
The only government body to investigate the collapse of Building 7
was a group of
selected and supervised by FEMA.
In their report they present an incredible scenario in which fires
cause the collapse of the building, and admit that it has
"a low probability of occurrence".
If fires leveled Building 7 it would be the first case in history
of fires causing the total collapse, or even the partial collapse,
of the columns in a steel-framed high-rise.
Fires far more severe than those observed in Building 7 caused
no damage to the steel columns of other buildings.
WTC7.net highlights the absurdity of the idea that random damage
could have caused this building to undergo a demolition-style implosion.
e x c e r p t
Fires have never been known to damage steel columns in highrise buildings,
but if they could, the damage would be produced gradually and would
be localized to the areas where the fire was the most intense.
No combination of debris damage, fuel-tank explosions, and fires
could inflict the kind of simultaneous damage to all the building's columns
required to make the building implode.
The precision of such damage required to bring Building 7 down
into its footprint was especially great
given the ratio of its height to its width and depth.
Any asymmetry in the extent and timing of the damage would
cause such a building to topple.
One interesting detail about the building's collapse is that the
eastern block of the mechanical penthouse dropped six seconds
before the entire building fell.
(This structure was far from any of the areas of fire observed.)
'Plaguepuppy' suggested this might have been to adjust the load for
a more precise demolition.
This sort of collapse is precisely what would be expected from a classical
controlled demolition, with the charges going off at ground level to allow the
building to settle into its own footprint. Of all the collapses WTC-7 was the
most precise, with almost all the wreckage confined to the footprint of the
building. It appears that some internal charges were set off to "adjust" the
internal structure of the building for an orderly collapse, causing the left
end of the penthouse to drop.
The building had an unusual design because it had to
be built over an existing three story tall electrical substation, leading to a
large transfer truss through the middle of the building above the electrical
gear. Such a non-homogeneous structure would not fall perfectly straight
without some preparation.
The advance drop of the eastern penthouse may also have been
planned for human engineering purposes,
giving the report-writers something to point to in order to
make the collapse seem less precipitous than it was.
page last modified: 2008-10-02