In 1971, the National Emergency Warning Center accidentally told US radio stations to suspend all broadcasts, presumably because the world was ending in a nuclear fireball. It took them 40 minutes to correct this apocalyptic gaffe.
Conelrad Adjacent has documented the remarkable 40 minutes the world ended. Some stations simply went off the air in shock while others, like WOWO-AM in Fort Wayne, Indiana, aired the Emergency Broadcast warning. WOWO-AM had the unique distinction of airing this dire message during a Partridge Family song.
On the morning of Saturday, February 20, 1971, Wayland S. Eberhardt, a civilian teletype operator, was going about his routine duties at the National Emergency Warning Center at Cheyenne Mountain in Colorado. One of the functions of "the Mountain" during this era was to send out the weekly Emergency Broadcast System (EBS) test directive to the nation's radio and television stations. They were, of course, also responsible for sending out the real warning. When stations received these messages they compared it against a card to determine what action to take.
At 7:33 a.m. local time on that fateful Saturday, Mr. Eberhardt, a fifteen-year veteran of his job, fed the wrong tape into the transmitter and set off a panic that is remembered to this day. He was later quoted by the New York Times as saying "I can't imagine how the hell I did it." But he did.
And here's the broadcast from WOWO-AM:
For the full story, check out Conelrad Adjacent. My favorite detail is the ridiculously lo-fi solution they came up with to ensure that the emergency broadcast tests and real emergency broadcasts wouldn't be swapped. Several drams of office organizing are worth an avoirdupois ton of mass hysteria.