New Details on the 1961 Goldsboro Nuclear Accident

A recently declassified report by Sandia National Laboratory, published today by the National Security Archive, provides new details on the 1961 Goldsboro, North Carolina, nuclear weapons accident. Both multi-megaton Mk 39 bombs involved in the mishap were in the "safe" position. Yet the force of the crash initiated mechanical actions that normally required human intervention. In both cases, the "fuzing sequence" had begun: an important step toward arming a nuclear bomb. Weapon 1, the one that came closest to detonation, landed intact, but by the time Weapon 2 hit the ground, it was in the "armed" setting because of the impact of the crash. The arming switch that had prevented Weapon 1 from detonating was in itself highly vulnerable. The Goldsboro incident is an alarming example of the great danger inherent in nuclear accidents.

Since the advent of the nuclear age, the nightmarish possibility of an accidental detonation has made weapons safety a boiler-plate item in the U.S. nuclear weapons program — yet potentially serious errors continue to occur. A series of 2013 reports on the Goldsboro accident provided a fresh reminder of the role of luck in preventing nuclear disaster: the same switch involved in the 1961 event had failed in other incidents.[1]

Eric Schlosser's extraordinary book Command and Control Nuclear Weapons, the Damascus Accident, and the Illusion of Safety, raises important questions about the record of nuclear weapons safety in the United States during and after the Cold War. Two major studies by Sandia National Laboratory, cited by Schlosser in his book, have been recently released by the Department of Energy in response to National Security Archive Mandatory Declassification Review requests and are included in this publication. Both are demanding studies which require attentive readers. One is a 1959 study of nuclear weapons safety when experts at the national nuclear laboratories were beginning to review the problem more comprehensively. The other is an overview of safety history published in 1987 which reviews the impact of changing weapons design on safety policy, the impact of accidents on policy, and initiatives taken by experts at Sandia to improve safety.

Also included in today's posting are recently declassified Joint Chiefs of Staff documents from early 1958 which address a problem that increased apprehensions about safety: the introduction of sealed-pit nuclear weapons into the arsenal. Embedding plutonium pits or highly-enriched uranium in the bombs or warheads themselves, unlike previous nuclear weapons where fissile material capsules were kept separate until arming occurred, this development made the weapons ready for use but created new vulnerabilities, including greater contamination risk. 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.