Five al-Qaeda militants hijacked American Airlines flight 77 on Sept. 11, 2001. The plane was on its way from Dulles Airport outside of Washington, D.C., to Los Angeles, CA. The plane made it as far as eastern Kentucky before the terrorists took over the plane, redirected it, and slammed it into the Pentagon.
The FBI added 27 images the agency took on the ground that day to their photo vault, as first responders raced to rescue the wounded and remove the dead from the shell of the nation's symbol of military power.
Debris from the plane and the building are highlighted. The attack killed 125 people in the Pentagon, as well as all aboard the flight: 53 passengers, six crew, and the five hijackers.
The Boeing 757 took off from Dulles ten minutes early, at 8:20 am.
Some of the passengers were 5th and 6th grade teachers and students on a National Geographic Society field trip, heading to the Channel Islands National Marine Sanctuary in Santa Barbara. One woman aboard had changed her flight at the last minute in order to get home in time for her husband's birthday.
Authorities estimate the flight was taken over between 8:51 and 8:54 in the morning, as the last communication with the real pilots was at 8:50. At 8:54, the flight deviated from its flight plan.
The terrorists were led by a trained pilot, as the other four herded the passengers to the back of the plane to prevent them from re-taking the aircraft.
The hijacker pilot did not respond to any radio calls. According to the 9/11 Commission report, at 8:56, American 77 turned off its transponder and disappeared from Indianapolis radar. The controller searched for the aircraft and tried to establish radio contact. He then tried to make contact through the airline. At this point, the Indianapolis controller had no knowledge of the situation in New York. He believed American 77 had experienced serious electrical and/or mechanical failure, and had possibly crashed.
With no transponder signal, the flight could only be found when it passed the path of ground-based radar.
According to the 9/11 Commission Report, at 9:25, the Command Center advised FAA headquarters that American 77 was lost in Indianapolis Center's airspace, that Indianapolis Center was looking for the aircraft.
While FAA radar equipment tracked the flight from the moment its transponder was turned off, this information was not available to controllers at Indianapolis Center, for technical reasons. The result was that Indianapolis Center never saw Flight 77 turn around and head back toward Washington. The plane traveled undetected for 36 minutes.
At this point, the FAA's Command Center and FAA headquarters knew the following: They knew two aircraft had crashed into the World Trade Center. They knew American 77 was lost. They knew that a hijacker on board American 11 had said "we have some planes." Concerns over the safety of other aircraft began to mount.
At 9:37:46 am, American Airlines Flight 77 crashed into the Pentagon. Military assistance had not been requested as the plane was literally not on their radar. Jets were just 150 miles away.
You can listen to the actual radio traffic about the flight at NPR.
USA Today detailed the victims of Flight 77.