US nuclear bomb nearly blew up in 1961 accident, declassified files show
A simple switch was all that prevented an atomic bomb exploding over North Carolina in 1961 after a B-52 broke up, documents reveal
The US Air Force came dramatically close to detonating a huge atomic bomb - 260 times more powerful than the device that devastated Hiroshima - over North Carolina in the United States in 1961, according to a newly declassified document.
The document, obtained by investigative journalist Eric Schlosser under the Freedom of Information Act, gives the first conclusive evidence that the US was narrowly spared a disaster of monumental proportions when two Mark 39 hydrogen bombs were accidentally dropped over Goldsboro, North Carolina, on 23 January that year.
The bombs fell to earth after a B-52 bomber broke up in mid-air, one of the devices behaving precisely the way a nuclear weapon was designed to behave in warfare: its parachute opened, its trigger mechanisms engaged, and only one low-voltage switch prevented untold carnage.
Each bomb carried a payload of 4 megatons - equivalent to 4 million tons of TNT explosive. Had the device detonated, lethal fallout could have been deposited over Washington, Baltimore, Philadelphia and as far north as New York city - putting millions of lives at risk.
Though there has been persistent speculation about how narrow the Goldsboro escape had been, the US government has repeatedly publicly denied that its nuclear arsenal has put Americans' lives in jeopardy through safety flaws.
But, in the newly published document, a senior engineer in the Sandia national laboratories responsible for the mechanical safety of nuclear weapons concluded that "one simple, dynamo-technology, low voltage switch stood between the United States and a major catastrophe".
Writing eight years after the accident, Parker Jones found that the bombs that dropped over North Carolina just three days after John F. Kennedy made his inaugural address as president were inadequate in their safety controls and that the final switch that prevented disaster could easily have been shorted by an electrical jolt leading to a nuclear burst. "It would have been bad news - in spades," he writes.