History of the United States (1991–2008) South Tower less than twenty minutes later at 9:03 A.M. (EST), resulting in the collapse of both 110 story skyscrapers, and the destruction of the World Trade Center. The third hijacked plane, American Airlines Flight 77, was crashed into the Pentagon (the headquarters of the United States Department of Defense) in Arlington County, Virginia, demolishing a section of the outer southwest facing wall. After discovering that their plane, United Airlines Flight 93, was going to be used as a missile, passengers attempted to regain control of the plane which had been redirected towards Washington, D.C. However, after regaining control from
Arlington County Fire Department transport units with one firefighter/EMT and one firefighter/paramedic. Arlington operates nine engine companies, three truck companies, two rescue companies and eight medic units. Additional medic units can be placed in service as necessary. The county is divided into two divisions, the North (112) and the South (111), with one Battalion Chief, an Advanced Paramedic Officer, an Assistant Fire Marshal and Deputy Fire Marshals in each division. Abbreviations: <nowiki>*</nowiki> - Indicates part-time units, often staffed during peak times only. Arlington County Fire Department is the primary all-hazards response agency for Arlington County, Virginia. In addition to ACFD, other fire departments operate