Twin Towers Weren't Faulty: Report

A new report commissioned by the leaseholder of the World Trade Center site has concluded that the twin towers did not collapse because of flaws in their structural design.

The study by a Manhattan engineering firm that used a computer program to recreate the attacks said damage caused by the planes, and fires that broke out as a result, caused both buildings to crumble during the terrorist attacks, The New York Times reported Tuesday.

The report's analysis contradicts the findings of an earlier federal investigation, which said the towers' unconventional design contributed to their collapse. The federal study said weak floor supports gave way during the Sept. 11, 2001, attacks, triggering a collapse of the entire building.

Larry Silverstein, the owner of the trade center property, paid for the new study as part of his $4 billion insurance lawsuit.