Jon D. Magnusson, chairman-CEO of Seattle-based
Skilling Ward Magnusson Barkshire Inc., one of the
successor firms to the engineer of record for the
World Trade Center, Skilling Helle Christiansen and
Robertson, says that in the dozens of media interviews
since the attacks, he is asked the same question: Why
did the towers collapse? He says he answers a
different question: How come they stood up so long?
Ninety-nine percent of all buildings would have
collapsed immediately had they been hit by a Boeing
767, says Magnusson. "The real question is how did
they stand up so long after the planes hit?" he says.
That provided precious time that gave occupants time
to escape. The answer, he says, is the redundancy
inherent in the design of the exterior structural tube
designed by Les Robertson and the late John Skilling.
The time between the attacks and the collapses
saved thousands of lives, he adds. "You can't harden
these buildings to take that kind of impact," says
Magnusson. "If you design for a 767, what about a 747
or an Airbus super jumbo?
"It's a losing proposition," he continues. "Even
if you could harden the buildings, with the awareness
that airplanes can be used as weapons, what about [the
vulnerability] of people at football games, in
cathedrals, in concert halls? The problem is not about
buildings. The real question is how do you keep
airplanes out of the hands of evil people? As we enter
this national dialogue, we need to make sure we're
focusing on the right problem."