Oh yes this is the incident I was referring to, actually. I thought it was the same. Somehow I remembered the troop buildup of Able Archer confirmed the invasion fear for the Soviets. But it sounds like that played no part in it. I must have remembered it wrong.
zimpenfish|3 years ago
From what I remembered, and a quick scan of Wikipedia[1], you're not wrong.
"In response, the Soviet Union readied their nuclear forces and placed air units in East Germany and Poland on alert. The Soviet 4th Air Army began loading nuclear warheads onto combat planes in preparation for war."
[1] https://en.wikipedia.org/wiki/Able_Archer_83