Malmstrom incident
In the pre-dawn hours of March 16, 1967, the crew of Echo Flight — one of several Minuteman I ICBM squadrons operated by the 341st Strategic Missile Wing at Malmstrom Air Force Base, Montana — watched as all ten of their nuclear-armed missiles transitioned simultaneously into a "No-Go" status. No maintenance had been scheduled. No command had been issued. No known technical fault could account for the simultaneous failure of ten separate, hardened, independently isolated systems.