American Physical Society Meeting in St. Louis Presentation (4/15/08): "Physics & Collapse of the South Tower of WTC"

Crockett Grabbe, University of Iowa


PRE-CONFERENCE ADDITION TO ABSTRACT: It is found that the force created in the second explosion is a SMOKING GUN, as its strength is nearly an order of magnitude or more larger than the strength of the force of gravity, disproving the NIST explanation of the South Tower collapse as gravitational caused by columns collapsing from the plane collision and subsequent fires.


Slide 1:  
South Tower before the collapse 
The S Tower (on the LHS) at 9:59 AM, 56 minutes after the plane collision, 
almost at the time the collapse initiates.

Slide 2:  
S Tower collapse 4 secs later :

o White horizontal ejections (which I call "squibs") are coming out E side, 
with pulverized white concrete ~ 2 floors BELOW the fires from the plane

o The top segment of the S Tower is leaning 4-5 degs

o There seems to be a crack in lean where smoke is ejecting

Slide 3:  
S Tower collapse 0.75 secs later

o The squib front has moved ~40 feet in t=3/4 sec, so is travelling ~ 40 mph
  AFTER using energy to break thru the walls

o The Tower lean has increased to 9 degs

o The crack appears to have become larger & emit more smoke

**Since energy E & momentum p are conserved, E & p of the squibs must have 
originated somewhere!

**Did E & p come from chemical E released in explosions in the horizontal 
direction?  We need to take a closer look of these squibs.

Slide 4:  
Close-up of SE corner of S Tower secs earlier  

o Thin fracture, just as squibs start emerging at levels below.

Slide 5:  
SE corner of S Tower 0.25 secs later

o ~ 5 ft of separation has quickly developed in 0.25 secs
Notice the impetus of sudden squib ejection is BELOW the level of that corner.

** Gravitational forces could NOT have caused that separation!  The 
MOST movement grav. force could produce in 0.25 secs is 0.5gt**2 = 1 ft.

Slide 6:  
SE corner of S Tower 0.75 secs later 

o A little more separation has developed in the corner along with a bit of 
smoke developing in the separation, 

o A 50 ft crack that extends to the S on this E side that has developed is

** Only an explosion produces F that can produce the p & E of separation,
and it MUST have been from the same explosions that produced the horizontal 
squibs at levels below it.

**Estimate for producing this separation:  E= mgs ~ 10**8 J = 0.25 ton of TNT.
This is equivalent to 50 sticks of dynamite.

Slide 7:  
Distant view of the Towers 1 second later than view in Slide 3 

o A massive gray cloud expansian has occurred at the bottom of the top segment.

o A drop in top of the tower has occurred -- that is because the concrete of
the top segment is being pulverized at bottom of the top segment (it is gray 
because the concrete is saturated with smoke from the fire of the top segment).

**Conservation of mass effectively PROVES top is dropping from pulverizing 
concrete (producing gray smoke) at the bottom of the top segment.

Slide 8:  
Distant view 0.75 secs later (where all HELL is breaking loose!)

o In 3/4 sec new white squibs have moved out over 100 ft, so are travelling
   ~ 50 m/s or ~ 100 mph!

o A sudden break has occured in the S Tower top segment corner, & right at
the break the top segment has shifted ~ 50-60 ft to the right & into page! 

o The top of the S Tower drops another ~ 50 ft

**A huge jolt of E & p is imparted to the top segment.  

**The MAXIMUM distance gravity force could move it is 0.5gt**2 = 9 ft, and that
is ONLY if we ignores all the E required to break the 2 parts of the edge apart!

**A force > [probably >>] 6X the force of gravity caused this shift!

** This is the SMOKING GUN that shows the NIST model that the S Tower collapsed
on its own from damage by planes & fire is WRONG!

Slide 9:  
Distant view 0.25 secs later 

o In just 0.25 secs the large E & p imparted still causes more rapid change.

Slide 10:  
Closeup perspective of the collapse from N direction 

o The top segment is falling almost S, and looks like it will topple off.

o It completely disappeared into the gray smoke clouds instead!

o The white & gray clouds are clearly distinct, coming from the separate
top & bottom segments
o Significant p has been imparted horizontal to pieces of cladding coming from
the bottom segment.  The pieces have moved up to 70 ft away from tower in a 
short descent downward.

Slide 11:  
Distant view of Towers at 1 sec later than Slide 9 

o The top segment has over 50% gone all up into the gray clouds that are 
expanding out.  

o Notice the bottom segment of the Tower is undeterred if nothing further 
happens!  It is stable, and the collapse would cease.

Slide 12:  
Collapsing S Tower seconds later 

o Notice a squib emerging later below the collapsing part in the collapse of S 

o Further release of breakup energy is needed to sustain the collapse, 
otherwise the lower segment would remain standing!

o Notice the small comet moving at high speeds atop the dust cloud on the LHS.
Either it has initially upward velocity or it came from above the tower!

Slide 13:  
World Trade Center war zone after the collapses 

o This complete shredding of the Towers in the WTC can be compared to building 
failures like this one from a quake in Japan, where most the collapsed 
building stays together.

Slide 14: 
Link to my article: "Response to NIST on E and P" (published online 1/29/08)

o NIST does not deal with p & E issues in 43 volumes they published on their
model for the planes and fires causing the 2 Tower collapses.

o This is reply to the sleazy, misleading answer on p & E for NIST's FAQ sheet 
  released 12/14/07  -- it has been published online for all to read.

CREDITS:  The distant views of the Towers in 2001 were filmed by NBC News.
The close-up views of the SE corner were filmed by SCT-1 of Spiegel TV.  The
films with these shots were put online by the 9-11 Research Project.

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