Loose Nukes at Home

No nuclear weapon has ever accidentally detonated. But this winter marks the fiftieth anniversary of several mishaps involving the handling of American nuclear weapons — an anniversary that comes at a time when the procedures for the handling of U.S. nukes are under renewed scrutiny.

On February 5, 1958 in the air over Georgia, a U.S. Air Force B-47 bomber collided with a fighter jet. Both planes were badly damaged. The B-47 happened to be carrying a nuclear bomb — one without a nuclear capsule and therefore incapable of a nuclear explosion — which the pilot jettisoned on purpose over the water for a safer landing. Despite months of searching and follow-up investigations through the years, the bomb was never found. It is presumably still sitting under the seabed in the waters off Savannah, Georgia.

A month later, on March 11, 1958, another B-47 dropped a nuclear bomb over the United States, this time by accident and over land. This bomb, too, was incapable of a nuclear explosion — but like the Georgia bomb, it still contained the conventional explosives that are used to trigger a nuclear blast. These were set off when the bomb landed in the garden of the Gregg family east of Florence, South Carolina, injuring the family, creating a huge crater in their yard, and all but destroying their house.

Although these two accidents were among the most prominent involving U.S. nuclear weapons, they were neither the first nor the worst. Others involved radioactive contamination, including two further incidents in the winter of 1958 involving American planes overseas. The closest the United States probably came to an accidental nuclear explosion was on January 24, 1961, four days after President Kennedy took office, when a B-52 bomber crashed in North Carolina. Several safety switches apparently failed on one of the bombs that had been aboard. As then-Secretary of Defense Robert McNamara explained two decades later, “The bomb’s arming mechanism had six or seven steps to go through to detonate, and it went through all but one.”

There are, needless to say, detailed procedures and processes in place to prevent accidents with nuclear weapons. But like all human endeavors, the construction, control, and transportation of nuclear weapons is susceptible to error. New evidence of this came just last year when six missiles with live nuclear warheads were accidentally flown across the United States in a B-52 on August 30, 2007 — and nobody noticed they were missing for more than a day. A report on this incident released in February 2008 by the Defense Science Board explains that, since the end of the Cold War, American practices for moving nuclear weapons have badly degraded — part of a larger worrisome “declining focus and an eroding nuclear enterprise.” The board has made a number of recommendations for improving nuclear safety; the Pentagon should move quickly to put them into practice.