Report: Intense blaze crippled sprinkler systems in trade center, contributing to collapse

<br>NEW YORK (AP) _ The intense fires that erupted when hijacked airliners hit the World Trade Center's twin towers disabled the water supply for hoses, sprinkler systems and other fire-suppression

Friday, March 29th 2002, 12:00 am

By: News On 6

NEW YORK (AP) _ The intense fires that erupted when hijacked airliners hit the World Trade Center's twin towers disabled the water supply for hoses, sprinkler systems and other fire-suppression equipment in the buildings, according to a federal report.

The structure of the buildings responded surprisingly well to the impact of the planes on Sept. 11, the report says, but the towers could not withstand the ensuing fires that burned as hot as 2,000 degrees and generated heat equivalent to the output of a nuclear power plant.

The findings of the report, commissioned by the Federal Emergency Management Agency and the American Society of Civil Engineers, were reported by The New York Times in Friday editions. The newspaper had obtained a draft copy of the report.

The report, which the newspaper said will be officially released in late April or early May, offers a detailed description of the sequence of events that brought the twin towers down.

The planes damaged support columns when they rammed into the towers, but the buildings successfully redistributed loads to other supports, the report said. It added that without the devastating fires, the towers probably would have remained standing indefinitely unless they were hit by an earthquake or a windstorm.

``The ability of the two towers to withstand aircraft impact without immediate collapse was a direct function of their design and construction characteristics, as was the vulnerability of the two towers to collapse as a result of the combined effects of the impacts and ensuing fires,'' the report states.

According to the report, the fireballs that erupted when the planes hit the towers burned perhaps a third of each plane's fuel. That initial explosion did little structural damage, but the fires from the remaining fuel _ which spread through several floors of office equipment and furniture _ brought the towers down.

Fire suppression systems in high-rise buildings are designed to allow fires to burn themselves out before a collapse can take place, but those systems failed in the trade center across the board, the report concluded.

The extraordinary circumstances surrounding the attack, the report noted, make it difficult to draw conclusions about the effectiveness of fire suppression systems in other buildings. The report said debris sent flying by the impact of the planes almost certainly sliced through pipes that supplied water for fire hoses and sprinklers.