7. November 9, 1979

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A simple act of mounting the wrong computer tape at a U.S. military installation caused sensors at four command centers to show that the United States was under attack, and that a large number of missiles were inbound from the Soviet Union. Fortunately, other radar and satellite sensors indicated that no attack was taking place and after six minutes of chaos and preparations for nuclear war, the alert was terminated. The tape that was accidently mounted contained data that was designed to simulate a full-scale nuclear attack by the U.S.S.R.