2,996 : The deadliest aviation-related disaster of any kind , considering fatalities on both the aircraft and the ground , was the destruction of the World Trade Center in New York City on September 11 , 2001 . On that morning , four commercial aircraft traveling on transcontinental flights from East Coast airports to California were hijacked after takeoff . The four hijacked aircraft were subsequently crashed in four separate suicide attacks against major American landmarks , by 19 Islamic terrorists affiliated with Al Qaeda . American Airlines Flight 11 and United Airlines Flight 175 were intentionally crashed into the North and South Towers respectively of the World Trade Center , destroying both buildings in less than two hours . The World Trade Center crashes killed 2,753 , the vast majority of fatalities being occupants of the World Trade Center towers or emergency personnel responding to the disaster . In addition , 184 were killed by American Airlines Flight 77 , which crashed into The Pentagon ( causing severe damage and partial destruction to the building 's west side ) . 40 passengers were also killed when United Airlines Flight 93 crashed into a Somerset County Pennsylvania field after passengers fought back and prevented the hijackers from reaching their designated target . This brought the total number of casualties of the September 11 attacks to 2,996 ( including the 19 terrorist hijackers ) . As deliberate terrorist acts , the 9/11 crashes were not classified as accidents , but as mass murder-suicide ; these events were subsequently treated by the United States and the member nations of NATO as an act of war and terrorism
United Airlines Flight 175
United Airlines Flight 175
Aviation accidents and incidents