B-52 bomber collides with a KC-135 jet tanker over Spain’s Mediterranean coast, dropping three 70-kiloton hydrogen bombs near the town of Palomares and one in the sea. It was not the first or last accident involving American nuclear bombs.

As a means of maintaining first-strike capability during the Cold War, U.S. bombers laden with nuclear weapons circled the earth ceaselessly for decades. In a military operation of this magnitude, it was inevitable that accidents would occur. The Pentagon admits to more than three-dozen accidents in which bombers either crashed or caught fire on the runway, resulting in nuclear contamination from a damaged or destroyed bomb and/or the loss of a nuclear weapon. One of the only “Broken Arrows” to receive widespread publicity occurred on January 17, 1966, when a B-52 bomber crashed into a KC-135 jet tanker over Spain.

The bomber was returning to its North Carolina base following a routine airborne alert mission along the southern route of the Strategic Air Command when it attempted to refuel with a jet tanker. The B-52 collided with the fueling boom of the tanker, ripping the bomber open and igniting the fuel. The KC-135 exploded, killing all four of its crew members, but four members of the seven-man B-52 crew managed to parachute to safety. None of the bombs were armed, but explosive material in two of the bombs that fell to earth exploded upon impact, forming craters and scattering radioactive plutonium over the fields of Palomares. A third bomb landed in a dry riverbed and was recovered relatively intact. The fourth bomb fell into the sea at an unknown location.

Palomares, a remote fishing and farming community, was soon filled with nearly 2,000 U.S. military personnel and Spanish civil guards who rushed to clean up the debris and decontaminate the area. The U.S. personnel took precautions to prevent overexposure to the radiation, but the Spanish workers, who lived in a country that lacked experience with nuclear technology, did not. Eventually some 1,400 tons of radioactive soil and vegetation were shipped to the United States for disposal.

Meanwhile, at sea, 33 U.S. Navy vessels were involved in the search for the lost hydrogen bomb. Using an IBM computer, experts tried to calculate where the bomb might have landed, but the impact area was still too large for an effective search. Finally, an eyewitness account by a Spanish fisherman led the investigators to a one-mile area. On March 15, a submarine spotted the bomb, and on April 7 it was recovered. It was damaged but intact.

Studies on the effects of the nuclear accident on the people of Palomares were limited, but the United States eventually settled some 500 claims by residents whose health was adversely affected. Because the accident happened in a foreign country, it received far more publicity than did the dozen or so similar crashes that occurred within U.S. borders. As a security measure, U.S. authorities do not announce nuclear weapons accidents, and some American citizens may have unknowingly been exposed to radiation that resulted from aircraft crashes and emergency bomb jettisons. Today, two hydrogen bombs and a uranium core lie in yet undetermined locations in the Wassaw Sound off Georgia, in the Puget Sound off Washington, and in swamplands near Goldsboro, North Carolina.

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