United States came dangerously close to nuclear bombing itself, new document shows (VIDEO)

It was a simple electronic switch that prevented a nuclear disaster 260 times worse than Hiroshima from happening in the United States nearly 52 years ago, a newly declassified document shows.

The incident happened over Goldsboro, North Carolina, when a B-52 bomber lost fuel and began plummeting to earth.

The pilots ejected as the aircraft dumped two nuclear bombs to the ground, one in full attack mode. Of four safety devices that prevent a nuclear detonation in that bomb, three had failed (the second bomb landed in a tree).

“One simple, dynamo-technology, low voltage switch stood between the United States and a major catastrophe,” writes the report’s author, Parker F Jones, a nuclear weapons safety supervisor from Sandia national laboratories.

He wrote the report in 1969 while scrutinizing an earlier analysis of the “Goldsboro caper,” as he called it.

The Guardian has published the document – called “Goldsboro Revisited, or How I Learned to Mistrust the H Bomb” – for the first time. It was uncovered by author Eric Schlosser through a freedom of information request.

More from GlobalPost: Hiroshima’s forgotten victims as told by a Korean survivor

While what happened at Goldsboro has long been known, the new document reveals just how close it was to disaster. It also appears to refute claims by the US government that a nuclear explosion was unlikely, the Guardian says.

Schlosser, author of “Fast Food Nation,” used the information for his new book, “Command and Control.”

The way he frames America’s history with A-bombs and H-bombs, that a runaway nuclear device has never “accidentally” exploded somewhere in the world is akin to miraculous.

Schlosser says there were 700 “significant” events involving 1,250 nuclear weapons from 1950 to 1968, the Guardian reports.

Goldsboro could’ve been about the worst, with its four-megaton bombs equal to four million tons of TNT (by comparison, Hiroshima’s bomb was about 15,000 tons of TNT).

Fallout would’ve likely reached New York City, needless to say endangering countless millions.

A Fox News report on the incident, also documented in the book “The Goldsboro Broken Arrow,” says there are still parts of the nuclear bomb buried deep beneath the North Carolina soil.

More from GlobalPost: How Hiroshima marks the atom bomb’s anniversary