How the day unfolded

8:15am

United Airlines Flight 175 takes off from Boston for LA, with nine crew members and 56 passengers, including five hijackers.

8:42am

San Francisco-bound United Airlines Flight 93 takes off at Newark. Seven crew members, 33 passengers and four hijackers are on board.

8:50-54am

Flight 77 is hijacked.

9:00am

A flight attendant aboard Flight 175 alerts air traffic control that a hijacking is underway.

9:03am

Flight 175 crashes into the South Tower of the World Trade Center between the 77th and 85th floors.

9:28am

Flight 93 is hijacked.

9:57am

Passengers aboard Flight 93 begin a revolt against the hijackers in an attempt to take back the plane.

10:03am

United Airlines Flight 93 crashes near Shanksville, Pennsylvania, after passengers and crew storm the cockpit. All 44 people on board are killed.

7:59am

American Airlines Flight 11 departs from Boston’s Logan International Airport, bound for Los Angeles. On board are 11 crew members and 81 passengers, including five hijackers.

8:20am

American Airlines Flight 77, en route to LA, takes off from Washington DC. Six crew members, 53 passengers and five hijackers are on board.

8:46am

Flight 11 crashes into the North Tower of the World Trade Center between the 93rd and 99th floors.

9:37am

American Airlines Flight 77 crashes into the Pentagon. The crash and fire kill 59 on the plane and 125 on the ground.

9:45am

United States airspace is shut down; all operating aircraft are ordered to land at the nearest airport.

9:59am

The South Tower collapses in 10 seconds after burning for 56 minutes. More than 800 people in and around the building are killed.

10:28am

The North Tower collapses 102 minutes after being struck by Flight 11. More than 1,600 in and around the building are killed.