A Boeing 757 -223 was flying as American Airlines Flight 77 on the morning of September 11, 2001. Bearing registration N644AA, the plane was heading from Dulles Airport (in Virginia, near Washington, DC) to LAX (Los Angeles International Airport) when it was hijacked. This image depicts the plane at DCA (Washington’s National Airport) during March of 1995. Hijackers crashed the plane into the Pentagon, a few miles away from DCA. Photo by Sunil Gupta; online via Wikimedia Commons. GNU Free Documentation License, Version 1.2 only.
American Airlines Flight 77, a Boeing 757, left Washington’s Dulles Airport at 08:20 EDT. Sixty-four people were going to Los Angeles, including four flight attendants and two pilots.
Eyewitnesses on the ground saw the plane approach Washington from the southwest. When it was just outside the city, the plane made a 270-degree turn and headed straight for the Pentagon (headquarters of America's Department of Defense).
Everyone on the plane, plus hundreds of people in the Pentagon, died. The picture below, by U.S. Navy Journalist 1st Class Mark D. Faram, depicts part of the plane's debris on the Pentagon lawn. The Navy describes the photo:
Wreckage from the hijacked American Airlines FLT 77 sits on the west lawn of the Pentagon minutes after terrorists crashed the aircraft into southwest corner of the building. The Boeing 757 was bound for Los Angeles with 58 passengers and 6 crew. All aboard the aircraft were killed, along with 125 people in the Pentagon. Online via U.S. Navy.
Author and TV commentator Barbara Olson, wife of U.S. Solicitor General Theodore Olson, called her husband twice during the ordeal. She reported the hijackers were armed with knife-like weapons and asked her husband, "What should I tell the pilot to do?"
The pilot, of course, was no longer in control of the plane.