USA Today
by Michael Winter
September 20, 2013

One of two hydrogen bombs that a doomed B-52 accidentally dropped on North Carolina in 1961 came perilously close to exploding, according to a recently declassified report.

The 4-megaton Mark 39 bombs -- each packing 260 times the explosive power of the weapon that decimated Hiroshima -- broke loose over Goldsboro, N.C., as the bomber went into a tailspin and crashed.

The Mark 39 hydrogen bomb had an explosive yield of 4 megatons, equal to 4 million tons of TNT. Two fell accidentally on Goldsboro, N.C., in 1961, and one nearly detonated. All four safety mechanisms designed to prevent accidental detonation worked properly on one bomb, which landed in a meadow, but three failed on the other, and only a low-voltage switch kept it from exploding upon impact in a field in Faro, N.C., said the 1969 report.

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http://www.usatoday.com/story/news/natio...c-bomb/2845381/