On the morning of September 11, 2001, nineteen al-Qaeda hijackers commandeered four commercial airliners and used them to attack the United States, killing thousands of people in New York City, Arlington, Virginia, and rural Pennsylvania. This September 11 attacks timeline records the day’s events in sequence, from the first hijacking to the collapse of the World Trade Center towers, and closes with the recovery effort and the response that followed.
September 11 Attacks Timeline: The Attacks Unfold
American Airlines Flight 11, a Boeing 767 traveling from Boston to Los Angeles, was hijacked shortly after its 7:59 a.m. departure and flown into the World Trade Center’s North Tower at 8:46 a.m., striking between the 93rd and 99th floors. Seventeen minutes later, at 9:03 a.m., United Airlines Flight 175, also en route from Boston to Los Angeles, was flown into the World Trade Center’s South Tower, an impact captured live on television as news crews were already covering the North Tower fire. At 9:37 a.m., American Airlines Flight 77, hijacked after departing Washington Dulles International Airport, struck the Pentagon’s west wall. The fourth hijacked aircraft, United Airlines Flight 93, had left Newark bound for San Francisco; passengers and crew, having learned by phone of the other hijackings, organized to storm the cockpit. The hijackers crashed the plane into a field near Shanksville, Pennsylvania, at 10:03 a.m., killing all 44 people aboard. The 9/11 Commission Report concluded the hijackers had intended Flight 93 to strike the U.S. Capitol or the White House.
September 11 Attacks Timeline: The Towers Fall and the Response Begins
The South Tower, struck second, collapsed first, at 9:59 a.m., fifty-six minutes after being hit. The North Tower collapsed at 10:28 a.m., one hour and forty-two minutes after Flight 11 struck it. Both collapses sent debris and dust clouds through Lower Manhattan and damaged or destroyed surrounding buildings, including 7 World Trade Center, which collapsed later that afternoon. New York City firefighters, police officers, and Port Authority personnel had been evacuating occupants and searching the towers for survivors when the buildings came down; 343 firefighters and 72 law enforcement officers were among those killed. In Arlington, firefighters fought the blaze at the Pentagon for hours before it was brought under control. Within minutes of the second impact, the Federal Aviation Administration grounded all civilian aircraft in U.S. airspace, and bridges, tunnels, and government buildings across the country were closed or evacuated as the scale of the coordinated attack became clear.
September 11 Attacks Timeline: Aftermath and Remembrance
Rescue and recovery operations continued at the World Trade Center site, known as Ground Zero, for months, as firefighters, police, and volunteers searched the wreckage first for survivors and later for remains. According to the National September 11 Memorial & Museum, 2,977 people were killed across the four attack sites, not including the 19 hijackers: 2,753 at the World Trade Center, 184 at the Pentagon, and 40 aboard Flight 93 near Shanksville. On October 7, 2001, the United States and allied forces launched military action in Afghanistan, targeting al-Qaeda and the Taliban government that had sheltered it, opening a conflict that continued for two decades. The National September 11 Memorial & Museum opened at the World Trade Center site on the tenth anniversary of the attacks, its twin reflecting pools set within the towers’ original footprints, and September 11 is observed in the United States each year as Patriot Day.
Frequently Asked Questions
How many people died in the September 11 attacks?
According to the National September 11 Memorial & Museum, 2,977 people were killed across the four attack sites, not including the 19 hijackers: 2,753 at the World Trade Center, 184 at the Pentagon, and 40 aboard United Airlines Flight 93.
Which flights were hijacked on September 11, 2001?
Nineteen hijackers took control of four commercial flights: American Airlines Flight 11 and United Airlines Flight 175, both bound from Boston to Los Angeles, American Airlines Flight 77 from Washington to Los Angeles, and United Airlines Flight 93 from Newark to San Francisco.
What happened to United Airlines Flight 93?
After passengers learned of the other hijackings by phone and stormed the cockpit, the hijackers crashed the plane into a field near Shanksville, Pennsylvania, at 10:03 a.m., short of its likely intended target in Washington, D.C.
What was the U.S. response to the September 11 attacks?
On October 7, 2001, the United States and allied forces launched military action in Afghanistan against al-Qaeda and the Taliban government that had sheltered it, the opening phase of a conflict that lasted two decades.