Premise: September 11 attacks . A third plane , American Airlines Flight 77 , was crashed into the Pentagon ( the headquarters of the United States Department of Defense ) in Arlington County , Virginia , leading to a partial collapse of the building 's western side . The fourth plane , United Airlines Flight 93 , initially was steered toward Washington , D.C. , but crashed into a field in Stonycreek Township near Shanksville , Pennsylvania , after its passengers tried to overcome the hijackers .
Hypothesis: The September 11 attacks did not involve airplanes.
Label: CONTRADICTION