In Memory of the September 11, 2001 Victims

In Memory of the September 11, 2001 Victims. . , On September 11, 2001, 2,606 people lost their lives at the World Trade Center. Hundreds were killed instantly by the impacts, while the rest were trapped and died when the towers collapsed. Of the people who were at or above the floors of impact in the North and South Towers, at least 1,366 of those died in the North Tower, and at least 618 died in the South Tower in which evacuation had begun before the second impact. Thus over 90% of the workers and visitors who died in the towers had been at or above the points of impact., A total of 411 emergency workers who responded to the scene died as they attempted to rescue people and fight fires. The New York City Fire Department (FDNY) lost 341 firefighters and 2 paramedics. The New York City Police Department lost 23 officers. The Port Authority Police Department lost 37 officers, and 8 additional emergency medical technicians (EMTs). , , The Pentagon, in Arlington County, Virginia, was severely damaged by the impact of American Airlines Flight 77 and ensuing fires, causing one section of the building to collapse. As it approached the Pentagon, the airplane’s wings knocked over light poles and its right engine smashed into a power generator, before crashing into the western side of the Pentagon, killing 125 people in the Pentagon and all 53 passengers and 6 crew members of Flight 77., On that very day, hijackers had also taken control of United Airlines Flight 93. Several passengers and flight attendants were able to make telephone calls and learn that attacks had been made on the World Trade Center in New York and the Pentagon in Virginia. As a result, some of the passengers decided to mount an attempt to regain control of the aircraft. During the attempt, however, the plane crashed into a field in Stonycreek Township, Pennsylvania, 150 miles northwest of Washington, D.C. All on board, including the four hijackers, were killed. Many witnessed the impact from the ground and news agencies began reporting the event within the hour. , Facts About the World Trade Center Artifact , The 110-story Twin Towers, rising 1,368 and 1,362 feet, remained the world’s tallest and largest buildings., As the diagram and photograph illustrates, the perimeter wall structures were assembled from prefabricated units consisting of 3 column sections and 3 spandrel plate sections welded together., The external columns carried some of the dead and imposed floor load (from those parts of the floor nearer the perimeter than the core) whilst the truss beams carried the remainder of the floor loading to the core. The plates connecting the perimeter columns are important in resisting horizontal forces. This is why they survived the impacts for sufficient time for upwards of 20,000 people to escape.