historyWikipedia1979 · Fort Ritchie, Maryland, USA
A training tape nearly convinced the US it was under Soviet nuclear attack
On 9 November 1979, computers at NORAD and at a backup command centre in Maryland showed what looked like a massive Soviet missile strike on the United States. Interceptor aircraft were launched and officials prepared for the worst. But the early-warning radars and satellites showed no attack, and after several tense minutes officers concluded it was a false alarm and cancelled it. The cause was a technical error: a simulation tape of a Soviet attack, used to train operators, had been loaded into the live warning system by mistake. The incident is one of several Cold War false alarms in which human judgement, rather than automation, prevented a catastrophe. The system was changed to separate training from live operations.
The training scenario was stored on tape and ran through the same computers as real warnings, so it looked like real tracks. Operators checked the satellites and radars independently, saw nothing incoming, and ruled out a real attack.
Nuclear alerts leave very little time for decisions, so a computer fault can look like a war. Cross-checking data from independent sensors, as the officers did, stopped a mistake from becoming a disaster.
In 1983 a Soviet officer, Stanislav Petrov, similarly judged that a satellite warning of US missiles was a false alarm.
From Wikipedia, the free encyclopedia · text CC BY-SA 4.0
Image: Wikimedia Commons
