Two nuclear bombs fell on North Carolina in 1961 after a U.S. Air Force bomber came apart in mid-air, a recently declassified report at the National Security Archive revealed.
The bombs, which could have created a disaster as large or worse than Hiroshima and Nagasaki, dropped near Goldsboro, North Carolina.
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The details contained in a report from Sandia National Laboratory show that the multi-megaton Mk 39 bombs were in a "safe" position, but that the force of the crash caused a "fuzing sequence" to begin, a Security Archive release said.
That sequence is the first step in arming the bombs. One of the bombs, called Weapon 1, in the report, came closest to detonation, the release said.
“The arming switch that had prevented Weapon 1 from detonating was in itself highly vulnerable,” the release said. “The Goldsboro incident is an alarming example of the great danger inherent in nuclear accidents.”
"By the slightest margin of chance, literally the failure of two wires to cross, a nuclear explosion was averted," then-Secretary of Defense Robert McNamara said.
The declassified documents also revealed Joint Chiefs of Staff documents from early 1958 that talked about sealed-pit nuclear weapons in the arsenal, which created new risks.
"While the Joint Chiefs of Staff dismissed the risk of an accidental detonation — special features on the weapons allegedly made the probability a 'negligible factor' — sealed-pit weapons would figure in the major accidents of the following years, including Jonesboro (1961), Palomares, Spain (1966) and Thule, Greenland (1968), where they would do considerable environmental damage," the Security Archive release said.
The accidental dropping of the Goldsboro bombs was first revealed in a 2013 book "Command and Control" by Eric Schlosser.
CNN cited 21 declassified incidents between 1950 and 1968 when nuclear weapons were “lost, accidentally dropped, jettisoned for safety reasons or on board planes that crashed.”
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