Scientists simulate jet colliding with World Trade Center

Video simulates 9/11 attacks

NEW YORK (CNN) -- A computer simulation of the September 11, 2001, attack on the World Trade Center, posted on the Web site YouTube by Purdue University researchers, shows how hijacked planes crashed through the twin towers, stripping fireproofing materials from the steel columns and eventually leading to their collapse.

The 3-D animation, part of a Purdue study that took two and a half years to complete, will hopefully help engineers design safer buildings, researchers said.