United Airlines Flight 93 in the context of "Flight 93 National Memorial"

The September 11 attacks, colloquially known as 9/11, were four coordinated Islamist terrorist suicide attacks by al-Qaeda against the United States in 2001. Nineteen terrorists hijacked four commercial airliners, then flew one into each of the Twin Towers at the World Trade Center in New York City, and another into the Pentagon, the headquarters of the U.S. Department of Defense, in Arlington County, Virginia. The fourth plane crashed in a rural Pennsylvania field during a passenger revolt. In response to the attacks, the United States waged the global war on terror over decades, to eliminate hostile groups deemed terrorist organizations, and the governments purported to support them.

Ringleader Mohamed Atta flew American Airlines Flight 11 into the North Tower of the World Trade Center complex at 8:46 a.m. Seventeen minutes later at 9:03 a.m., United Airlines Flight 175 hit the South Tower. Both collapsed within an hour and forty-two minutes, destroying the remaining five structures in the complex. American Airlines Flight 77 crashed into the Pentagon at 9:37 a.m., causing a partial collapse. The fourth and final flight, United Airlines Flight 93, was believed by investigators to target either the United States Capitol or the White House. Alerted to the previous attacks, the passengers revolted against the hijackers who crashed the aircraft into a field near Shanksville, Pennsylvania, at 10:03 a.m. The Federal Aviation Administration ordered an indefinite ground stop for all air traffic in U.S. airspace, preventing any further aircraft departures until September 13 and requiring all airborne aircraft to return to their point of origin or divert to Canada. The actions undertaken in Canada to support incoming aircraft and their occupants were collectively titled Operation Yellow Ribbon.

The September 11 attacks of 2001, in addition to being a unique act of terrorism, constituted a media event on a scale not seen since the advent of civilian global satellite links. Instant worldwide reaction and debate were made possible by round-the-clock television news organizations and by the internet. As a result, most of the events were known by a large portion of the world's population as they occurred.

The attacks themselves lasted less than two hours; the first hijacking commenced at approximately 8:14 am, and the final hijacked plane crashed at 10:03 am. All times given are in Eastern Daylight Time, (UTC−04:00).

The September 11 attacks, colloquially and perhaps more commonly known as 9/11, were four coordinated Islamist terrorist suicide attacks by al-Qaeda against the United States in 2001. Nineteen terrorists hijacked four commercial airliners, then flew one into each of the Twin Towers at the World Trade Center in New York City, and another into the Pentagon, the headquarters of the U.S. Department of Defense, in Arlington County, Virginia. The fourth plane crashed in a rural Pennsylvania field during a passenger revolt. In response to the attacks, the United States launched and waged the global war on terror over two decades, with the mission to eliminate hostile groups deemed terrorist organizations, and the governments purported to support them.

Ringleader and hijacker Mohamed Atta flew American Airlines Flight 11 into the North Tower of the World Trade Center complex at 8:46 a.m. Seventeen minutes later at 9:03 a.m., hijacker Marwan al-Shehhi flew United Airlines Flight 175 into the South Tower. Both collapsed within an hour and forty-two minutes, destroying the remaining five structures in the complex. Hijacker Hani Hanjour flew American Airlines Flight 77 into the Pentagon at 9:37 a.m., causing a partial collapse. The fourth and final flight, United Airlines Flight 93, flown by hijacker Ziad Jarrah, was believed by investigators to target either the United States Capitol or the White House. Alerted to the previous attacks, the passengers revolted against the hijackers who crashed the aircraft into a field near Shanksville, Pennsylvania, at 10:03 a.m. The Federal Aviation Administration ordered an indefinite ground stop for all air traffic in U.S. airspace, preventing any further aircraft departures until September 13 and requiring all airborne aircraft to return to their point of origin or divert to Canada. The actions undertaken in Canada to support incoming aircraft and their occupants were collectively titled Operation Yellow Ribbon.

Shanksville is a borough in Somerset County, Pennsylvania, United States. It has a population of 199 as of the 2020 U.S. census. It is part of the Somerset, Pennsylvania Micropolitan Statistical Area and is located 78 miles (126 km) southeast of Pittsburgh and 226 miles (364 km) west of Philadelphia.

Shanksville garnered global attention during the September 11 attacks when United Airlines Flight 93, bound from Newark, New Jersey, for San Francisco, crashed in adjacent Stonycreek Township after its passengers rebelled against the flight's al-Qaeda terrorist hijackers. It was the only one of the four hijacked planes that failed to reach the terrorists' intended target.

Mohammed Mani Ahmad al-Qahtani (Arabic: محمد ماني احمد القحطاني; sometimes transliterated as al-Kahtani; born November 19, 1975) is a Saudi citizen who was detained as an al-Qaeda operative for 20 years in the United States's Guantanamo Bay detention camps in Cuba. Qahtani allegedly tried to enter the United States to take part in the September 11 attacks as the 20th hijacker and was due to be onboard United Airlines Flight 93 along with the four other hijackers. He was refused entry due to suspicions that he was trying to illegally immigrate. He was later captured in Afghanistan in the Battle of Tora Bora in December 2001.

After military commissions were authorized by Congress, in February 2008, Qahtani was charged on numerous counts. In May, the charges were dropped without prejudice. New charges were filed against him in November 2008 and dropped in January 2009, as evidence had been obtained through torture and was inadmissible in court. This was the first time an official of the Bush administration had admitted any torture of detainees at Guantanamo.

The September 11 attacks, colloquially known as 9/11, were four coordinated Islamist terrorist suicide attacks by al-Qaeda against the United States in 2001. Nineteen terrorists hijacked four commercial airliners, then flew one into each of the Twin Towers at the World Trade Center in New York City, and another into the Pentagon, the headquarters of the U.S. Department of Defense, in Arlington County, Virginia. The fourth plane crashed in a rural Pennsylvania field during a passenger revolt. In response to the attacks, the United States launched and waged the global war on terror over two decades, with the mission to eliminate hostile groups deemed terrorist organizations, and the governments purported to support them.

Ringleader and hijacker Mohamed Atta flew American Airlines Flight 11 into the North Tower of the World Trade Center complex at 8:46 a.m. Seventeen minutes later at 9:03 a.m., hijacker Marwan al-Shehhi flew United Airlines Flight 175 into the South Tower. Both collapsed within an hour and forty-two minutes, destroying the remaining five structures in the complex. Hijacker Hani Hanjour flew American Airlines Flight 77 into the Pentagon at 9:37 a.m., causing a partial collapse. The fourth and final flight, United Airlines Flight 93, flown by hijacker Ziad Jarrah, was believed by investigators to target either the United States Capitol or the White House. Alerted to the previous attacks, the passengers revolted against the hijackers who crashed the aircraft into a field near Shanksville, Pennsylvania, at 10:03 a.m. The Federal Aviation Administration ordered an indefinite ground stop for all air traffic in U.S. airspace, preventing any further aircraft departures until September 13 and requiring all airborne aircraft to return to their point of origin or divert to Canada. The actions undertaken in Canada to support incoming aircraft and their occupants were collectively titled Operation Yellow Ribbon.

Ziad Samir Jarrah (Arabic: زياد سمير جراح; 11 May 1975 – 11 September 2001), also known as Ziad al-Jarrah, was a Lebanese terrorist who was a member of al-Qaeda, a pan-Islamist militant organization. During the 11 September attacks in 2001, he was one of 19 al-Qaeda members who hijacked four American commercial flights in an attempt to crash them into national landmarks in the country. Jarrah's group hijacked United Airlines Flight 93, departing Newark, New Jersey, for San Francisco, but they failed to reach their target when the plane crashed.

Jarrah grew up in a secular and wealthy family living in Beirut during the Lebanese Civil War (1975-1990). In 1996, he moved to Germany to study aerospace engineering at the Hamburg University of Applied Sciences. In Hamburg, he became part of a clandestine cell system known as the Hamburg cell with fellow hijackers Mohamed Atta and Marwan al-Shehhi, among many others. In 1999, member Ramzi bin al-Shibh took the cell to Afghanistan to meet al-Qaeda's leader, Osama bin Laden, where they were instructed to receive flight training. In 2000, Jarrah enrolled in a flight school in Florida.

The Hamburg cell (German: Hamburger Zelle; Arabic: خلية هامبورغ, Khalia Hamburh) were a clandestine cell system of eleven Islamist terrorists living in Hamburg, Germany, in the late 1990s. In 1999, they traveled to Afghanistan to meet with leaders of the militant organization al-Qaeda, and then returned to Hamburg to work on al-Qaeda's plan for terrorist attacks against the United States. This led to the September 11 attacks in 2001, in which four American airliners were hijacked in an attempt to crash them into important landmarks in the country.

Germany, the U.S., and the United Nations collectively consider eleven people to have been members. Three of them—Mohamed Atta, Marwan al-Shehhi, and Ziad Jarrah—were hijackers of American Airlines Flight 11, United Airlines Flight 175, and United Airlines Flight 93, respectively. In 2002, Ramzi bin al-Shibh stated that only he and those three men were members. However, authorities also list: Abdelghani Mzoudi, Mamoun Darkazanli, Mohammed Haydar Zammar, Mounir el-Motassadeq, Naamen Meziche, Said Bahaji, and Zakariya Essabar.