American Airlines Flight 77
Also called: AA77, Flight 77
On 11 September 2001 an airliner that left Washington Dulles at 8:20 a.m. was hijacked, turned back near Ohio and flown into the Pentagon at 9:37.

Air Force Tech. Sgt. Cedric H. Rudisill · Public domain · Source
The Boeing 757 carried 59 crew and passengers — and five hijackers. Bound for Los Angeles, it was hijacked near the Ohio–Kentucky border and turned back east. Passenger Barbara Olson phoned her husband, the US Solicitor General, to report what was happening.
At 9:37 a.m., after a wide turn southwest of Washington, the plane flew in low and struck the west wall of the Pentagon. The 59 people aboard and 125 in the building were killed.