On September 11, 2001, the members of Al Qaeda hijacked four American commercial airplanes- American Airlines Flight 11, United Airlines Flight 175, American Airlines Flight 77, and United Airlines Flight 93.  The first two planes hit the World Trade Center in New York City, the third plane crashed into the Pentagon and the fourth plane Flight 93 crashed into an open field in rural Pennsylvania. It is later reported that nearly 3000 people lost their lives in September 11 attack. In fact, the timely interference of passengers and crew members in Flight 93 decreased the number of deaths in the September 11 attacks. The main objective behind the hijacking of this flight is still mysterious, but it is believed that terrorist groups aimed to attack the American president’s official residence, the U.S. Capitol, Camp David, and the US nuclear power plants.
Attack on Flight 93 
United Airlines Flight 93 was an early morning flight flown from Newark, a New Jersey city to San Francisco. On that day, it departed from Newark Liberty international airport at 8:42 a.m, nearly 45 minutes late from the scheduled departure time. The flight contained seven crew members and 40 passengers. Four hijackers managed to infiltrate the plane with knives and box cutters. However, the hijacker's entire plan of attack was disrupted due to the late departure of the flight. Even though the terrorists were on the flight for nearly 40 minutes, they did not try to get control of the airliner. Meanwhile, at 9:19 a.m the United Airlines flight dispatcher sent messages to flight 93 pilots informing them about the world trade center attacks and urged them to be careful of any cockpit intrusion. Upon receiving this message, Jason Dahl, the captain of the flight responded by requesting the airline dispatcher to provide more information about the attack.
Around 9:28 am, the terrorists started the hijacking, and the captain of the flight issued a ‘Mayday’ distress call through radio transmission. In addition to that, air traffic controllers also heard the sounds of struggle.  There was a trained pilot among the hijackers, Ziad Jarrah, he ordered the passengers to sit down and frightened them by saying that they have placed bombs everywhere on the plane.  
As the captain of the flight was wounded by hijackers he could not do anything he moaned in the cockpit. However, he managed to disengage the autopilot and redirected the plane's radiofrequency. Hence, all the communication made by the hijackers with the passengers was transmitted to air traffic controllers. The hijackers shouted at the passengers to sit down and not to touch anything. He then took the flight towards Washington, D.C after resetting the autopilot.
Another woman in the cockpit cried and said that she don’t want to die. One of the terrorists informed Jarrah, who was controlling the flight that everything is going as planned.  At 09:39, Jarrah said that he wants everybody to be seated and they are taking the flight back to the airport. They have their own demands, so be quiet.
At 09:40, the hijackers decided to bring the first officer LeRoy Homer Jr back to the cockpit as they encountered an issue with the autopilot.
Passengers Fight Back
When the passengers and crew members came to know about what had happened to the other three hijacked flights.  They understood that their plane is also going to be used to carry out more attacks on the U.S. So, they gathered in the back of the plane and decided to fight back against the terrorists. They started calling their family member and officials on the ground using their cell phones and in-flight phones and informed them about the hijacking 
One of the passengers called his wife and informed her that all are going to die. He and other passengers are making a plan to retake the airplane and finally disconnected the call by saying he loved her so much.  Another passenger informed the airphone supervisor that terrorists have hijacked the flight and stabbed a passenger to death.  There are 4 terrorists on the plane, amongst them 2 had knives and a bomb was strapped around one of the hijacker’s waists. When the hijackers started to change the direction of the plane strongly towards the south he cried out that they are going down.   He also told that they are going to attack the hijackers and take the flight into the ground.  Then he started to recite the prayer with the airphone supervisor and requested other passengers to join with them. He also requested the supervisor to inform his family that he loved them so much. After that, the supervisor heard him saying to others in flight whether they are ready to do something. One of the passengers called his wife and informed her that the flight was hijacked by three dark-skinned men who seemed to be Iranian and that they were wearing red bandanas and holding knives. The United air traffic control coordinator sent a message to Air Traffic Control System Command Center that the flight was not responding and not flying through the intended route. Even though the hijackers turned off the transponder, the Cleveland controller kept on monitoring the flight on primary radar. 
A flight attendant called her husband and informed him that she just slipped into the aircraft kitchen while filling pitchers with boiling water to throw at the terrorists. She also told her that all the people are moving to the first-class cabin and she also have to go with them. At 09:35 another flight attendant called the maintenance facility and reported about the incident.  After the plane’s cockpit voice recorder was found, it revealed the sound of a woman struggling with one of the terrorists.
The hijacker then started to roll the airplane left and right with the aim to throw passengers off balance.  To avoid passengers from getting into the cockpit, Jarrah ordered another hijacker to hold from the inside. Jarrah always feared an attack from the passenger’s side at any time. To disrupt this, he pitched the airplane up and down. 
 The passengers managed to attack a hijacker who was standing guard outside the cockpit, At 10, Jarrah brought the plane back to its normal position and asked another hijacker whether they can put an end to it. For that, he responded by saying they could do that once all the passengers come back.  He again pitched the flight up and down. All the passengers on the flight started to cry. At 10, he stopped the violent maneuvers by reciting Takbir twice and asked another hijacker whether they can stop.  He responded by saying finish it off by destroying. The passengers continued their attack on the hijackers.  At 10:02, Jarrah screamed over and over again at passengers to give him back the plane’s yoke.  The aircraft later crashed into an empty field in Somerset County, Pennsylvania,
As the flight contained 7,000 gallons of fuel,  the fireball from the plane, burned hundreds of acres of earth and set the surrounding trees burning. The crash site was messed up with the debris from the crashed plane. 
Investigators later found out the flight’s data recorder and cockpit voice recorder. Medical examiners could later identify the 40 passengers, seven crew members, and four hijackers with the help of their DNA, dental records, or fingerprints.  However,  families of hijackers did not provide any genetic information. Within 2 weeks, the F.B.I was able to complete the investigation and submit the report.  
Post Attack
The families of flight 93’s passengers and crew began visiting the site many days after the crash. It was reported that nearly thirty thousand people visited the crash site in 2004. The families of passengers and crew members as well as federal authorities decided to build a memorial as an honour to the plane’s passengers and crew. Architects from Los Angeles had won the design contest for the memorial and started working on the project. ‘Crescent of Embrace’ was the name given for their plan. The first phase of the memorial was completed in September 2011.