1965 Searcy missile silo fire
The 1965 Searcy missile silo fire was an uncontrolled fire inside a Titan II missile silo near Searcy, Arkansas on August 9, 1965. The fire broke out while the missile silo was being renovated and improved; the missile was installed and fueled at the time, although the nuclear warhead had been removed.
Source: Wikipedia — 1965 Searcy missile silo fire (CC BY-SA 4.0)