1003 – United Airlines Flight 93 is crashed by its hijackers as passengers try to retake the plane over Somerset County, Pennsylvania. There are no survivors.
0945 – US Airspace is Shutdown
0814 – United Airlines Flight 175, a Boeing 767 carrying 56 passengers and nine crew members, departed from Logan International Airport, bound for Los Angeles International Airport, with five hijackers onboard.
0820 – American Airlines Flight 77, a Boeing 757 carrying 58 passengers and six crew members, departed from Washington Dulles International Airport in Fairfax and Loudoun Counties, Virginia, bound for Los Angeles International Airport, with five hijackers aboard.
0842 – United Airlines Flight 93, a Boeing 757 carrying 37 passengers and seven crew members departed from Newark International Airport, bound for San Francisco International Airport, with four hijackers aboard.
0842-0846 – Flight 175 is hijacked.