In 1958 an atomic bomb fell in the Greggs’ garden

11 March 1958, over Mars Bluff, South Carolina. A US Air Force B-47 bomber lost a Mark 6 bomb beside the Gregg family’s property. The aircraft had left Hunter Air Force Base for a training exercise in England; this was not a test drop. The capsule containing the nuclear material had not been fitted, so an atomic blast was impossible; the bomb’s conventional explosives did detonate when it hit the ground.

The shock wave destroyed the children’s playhouse, damaged the home and shed, and opened a crater about 21 metres wide and 10.7 metres deep. Walter Gregg, his wife Effie, their three children and their niece Ella Davies were nearby. Every one of them survived.

The crew circled the site to photograph the damage and warned the base with a message nobody there had ever needed to interpret: the aircraft had lost a device. On the ground, the family initially thought the Soviet Union had attacked South Carolina.

The part that prevented catastrophe was a safety measure of that era: the plutonium core travelled separately inside the aircraft. Without it there was a huge explosion, but no nuclear reaction. Ella Davies, who had been playing with the children, needed 31 stitches and was the only person admitted to hospital. All six people walked away alive.