Jets Impact the Twin Towers
The opening salvo in the escalating series of horrors on 9/11/01
was a jet smashing into the North Tower of the World Trade Center
at 8:46 AM.
The takeover of
had occurred almost 30 minutes earlier,
but it was the shocking impact with one of the famous Twin Towers
that awakened the world to the unfolding attack.
By 9:00 AM, television stations across the globe had gone live
with the story of the disaster in Lower Manhattan.
Thus many cameras were rolling when the South Tower was impacted
by a second jet at 9:03 AM, producing brilliant fireballs.
Impacts and Fireballs
The jet that hit the North Tower flew in perpendicular to the
tower's northeast face,
and impacted around the center of the 95th floor,
producing an impact gash that extended from the 92nd to the 98th floor.
Most of the plane apparently lodged in the tower's core structure,
the only piece of aircraft to emerge from the opposite side
being a dense piece of landing gear.
The burning jet fuel, atomized on impact, spilled out of the
impact gash and through broken windows on the southeast side.
In contrast, the jet that hit the South Tower, 18 minutes later,
veered to the right just before impact and
hit the rightmost third of the tower's southwest wall,
producing an impact gash that extended from the 78th to the 94th floor.
The diagonal trajectory through the building allowed most of the plane
to miss the tower's core structure,
and much of its fuselage appeared to emerge from the east corner,
while a great deal of the fuel escaped from the
northeast and southwest walls.
This produced huge fireballs that developed outside the building,
in contrast with the greater containment of the fireballs
in the North Tower impact.
The jet impacts destroyed sections of perimeter wall columns
on the faces of the towers they hit.
Although the collisions left imprints that extended out
to the wingtips of the jets, the ends of the wings destroyed only
the aluminum cladding covering the perimeter columns,
not the steel columns themselves.
The South Tower's wall was damaged less than the North Tower's,
since the columns at its impact zone were made of thicker steel.
North Tower's northeast perimeter wall from floors 93 through 98
South Tower's southwest perimeter wall from floors 78 through 82
According to FEMA's damage estimates,
The North Tower impact destroyed from 31 to 36 of its perimeter columns,
and the South Tower impact destroyed about 23 of its perimeter columns.
Since each tower had 240 perimeter columns,
the impacts destroyed only about 13 and 10 percent of the towers'
perimeter columns, and only on a few floors.
The Jet Fuel
In the popular imagination,
the jet fuel was the biggest factor in bringing down the towers.
News reports emphasized that the transcontinental flights were
fully loaded with fuel, while later government reports stated
that the 767s were carrying about 10,000 of their 24,000-gallon capacity,
and that most of the jet fuel likely burned off within five minutes.
Thus, the jet fuel primarily served to ignite the
rather than sustain them.
page last modified: 2006-05-28