United Airlines Flight 93

United Airlines Flight 93 was a domestic scheduled passenger flight that was hijacked by four Al-Qaeda terrorists on the morning of Tuesday, September 11, 2001, as part of the September 11 attacks. The hijackers planned to crash the plane into a federal government building in the national capital of Washington, D . The mission failed when the passengers fought back, forcing the terrorists to crash the plane in Shanksville in Somerset County, Pennsylvania, preventing them from reaching Al-Qaeda's intended target, but killing everyone aboard the flight. The airliner involved, a Boeing 757-200 with 44 passengers and crew, was flying United Airlines' daily scheduled morning flight from Newark International Airport in New Jersey to San Francisco International Airport in California, making it the only plane hijacked that day not to be a Los Angeles–bound flight. Forty-six minutes into the flight, the hijackers killed one passenger, stormed the cockpit, and struggled with the pilots as controllers on the ground listened in. Ziad Jarrah, who had trained as a pilot, took control of the aircraft and diverted it back toward the East Coast, in the direction of D . Khalid Sheikh Mohammed and Ramzi bin al-Shibh, considered principal instigators of the attacks, have claimed that the intended target was the U . Capitol Building. The flight's initial forty-two-minute delay meant that its passengers were able to learn of the attacks on the World Trade Center and the Pentagon, which had taken place shortly before. Since they knew that their flight was likely being hijacked as part of a suicide mission, they decided to fight back against the hijackers. In the ensuing struggle, the plane nosedived into a field near a reclaimed strip mine in Stonycreek Township, near Shanksville, about 65 miles (105 km) southeast of Pittsburgh and 130 miles (210 km) northwest of the capital. One person witnessed the impact from the ground, and news agencies began reporting the event within an hour. United Airlines Flight 93 was the fourth and final passenger jet to be commandeered by terrorists on September 11 and the only one that did not reach a target intended by Al-Qaeda. The hijacking was supposed to be coordinated with that of American Airlines Flight 77, which struck the Pentagon less than 26 minutes before the crash of Flight 93. A temporary memorial was built near the crash site soon after the attacks. Construction of a permanent Flight 93 National Memorial was dedicated on September 10, 2011, and a concrete and glass visitor center (situated on a hill overlooking the site) was opened exactly four years later.