On September 11, 2001, the Boeing 757-223, N644AA, was hijacked and crashed into the western side of The Pentagon, nearby Washington, DC at 9:37 AM EDT, killing all its 58 passengers and 6 crew.
The section of the Pentagon hit, consisting mainly of new, unoccupied offices, was damaged by the crash and the ensuing violent fire. The outermost section was largely destroyed. 125 people in the Pentagon died from the attack.
Barbara K. Olson had called her husband, United States Solicitor General Theodore Olson at the Justice Department twice from the plane to tell him about the hijacking and to report that the passengers and pilots were held in the back of the plane.
After the crash, the flight route designation, for future flights on the same route, was renumbered Flight 149.
See September 11, 2001 Terrorist Attack/Plane casualties for the flight manifest.