At 8:38 am , the Federal Aviation Administration ( FAA ) in Boston , Massachusetts , reported a possible hijacking and called the Otis Air National Guard Base control tower on Cape Cod , home to the Massachusetts ANG 's 102d Fighter Wing , to request military assistance . At that time , Major Dan Nash and Lieutenant Colonel Tim Duffy had air defense alert duty for the 102d . At 8:40 am Colonel Bob Marr , a Massachusetts Air National Guardsman serving as NORAD 's Northeast Air Defense Sector commander , learned from the FAA that American Airlines Flight 11 might have been hijacked . The two pilots immediately suited up and headed for their F-15s . Marr ordered Nash and Duffy into the air ; their F-15s were airborne within six minutes and as directed , headed for New York City , 153 miles away . Unknown to the pilots , American Airlines Flight 11 had crashed into the North Tower of the World Trade Center in New York City just as Colonel Marr was delivering his order . Meanwhile , at 8:43 am , the FAA reported another possible hijacking to the Northeast Air Defense Sector . That was Boston to Los Angeles United Airlines Flight 175 . At 9:02 am , with the F-15s still 71 miles away , that plane crashed into the World Trade Center 's South Tower
United Airlines Flight 175
United Airlines Flight 175
Air National Guard