On June 6, 1980, the Strategic Air Command was again alerted that the Soviet Union was attacking the US.

[mahatmakanejeeves]

Apparently it was the same component that had failed three days earlier. The folks at IT tried to replicate the conditions that had brought about the earlier false alarm, and they succeeded.

Nuclear weapons, AI, and the June 1980 US false alarms

{snip}

6 June 1980

In response to the 3 June incident, NORAD took some measures, such as communicating with all users, analyzing the data, and installing some "software trap" (whatever that means). At the same time, it also placed computers back to the 3 June configuration [NRD] and tried to "duplicate the error ... hoping to reproduce the erroneous data" [HGR]. Whether as a result of these efforts or by happenstance, the error did appear again.

The 6 June timeline is more confusing. HGR says that the first erroneous reading was displayed at 3:38pm, probably Eastern Daylight Time. The NRD account places the first display at 19:49. Not only the time zone is different, but the minutes are different as well. Since the absolute time doesn't matter that much, the description below will follow the NRD times.

{snip}

Mon Jun 8, 2026: On June 3, 1980, warning displays at the Strategic Air Command suddenly indicated that a Soviet SLBM attack was underway

Thu Jun 6, 2024: On this day, June 6, 1980, the Strategic Air Command was again alerted that the Soviet Union was attacking the US.

Tue Jun 4, 2024: On June 3, 1980, the Strategic Air Command was alerted that the Soviet Union was attacking the US.

Mon Jun 5, 2023: On June 3, 1980, the Strategic Air Command was alerted that the Soviet Union was attacking the US.