November 9, 1979: False "Soviet First Strike" Alarm:

The US made emergency retaliation preparations after NORAD saw on-screen indications that a full-scale Soviet attack had been launched.

No attempt was made to use the "red telephone" hotline to clarify the situation with the USSR and it was not until early-warning radar systems confirmed no such launch had taken place that NORAD realized that a computer system test had caused the display errors. A senator inside the NORAD facility at the time described an atmosphere of absolute panic. A GAO investigation led to the construction of an off-site test facility, to prevent similar mistakes.