(Rapid City Journal) Bob Hicks was spending a cold December night in his barracks 53 years ago at Ellsworth Air Force Base near Rapid City when the phone rang.
It was the chief of his missile maintenance team, who dispatched Hicks to an incident at an underground silo.
"The warhead," the team chief said, "is no longer on top of the missile."
Hicks eventually learned that a screwdriver used by another airman caused a short circuit that resulted in an explosion. The blast popped off the missile's cone — the part containing the thermonuclear warhead — and sent it on a 75-foot fall to the bottom of the 80-foot-deep silo.