Welcome to A People's Atlas of Nuclear Colorado

To experience the full richness of the Atlas, please view on desktop.
U.S. Air Force, Barrels being filled with contaminated soil from the Palomares Broken Arrow event being prepared for removal to the United States, ca. 1966, Wikimedia Commons

Issue Brief

"Broken Arrow" Events

As a country’s military builds its weapons program, accidental detonations may occur. If one of these detonations involves a nuclear device, the consequences could be severe. Since 1945, the U.S. military has lost, dropped, broken, or detonated nuclear missiles, resulting in accidents known as Broken Arrows. Contradictorily, the phrase “broken arrow” had signified peace in a highly acclaimed Although the film's Native American characters were largely depicted by white actors, "Broken Arrow" won a Golden Globe for “Best Film Promoting International Understanding," considered to be the first major Western since World War II to portray Native Americans "sympathetically."1950 Hollywood Western of that title depicting peaceful relations between Native Americans and white settlers. Although the military uses the term to describe only incidents unlikely to lead to war, the phrase has been adopted in the broader culture to refer to accidents that could result in a wide variety of outcomes: from long-term ecological impacts and human exposure to radioactive materials, to large-scale devastation or an international military confrontation.

In April of 1981, the Department of Defense (DOD) released a list of 32 Broken Arrows titled, U.S. Department of Defense, "Narrative Summaries of Accidents Involving U.S. Nuclear Weapons 1950-1980" (Washington, DC: Government Printing Office, 1981), iii, https://www-tc.pbs.org/wgbh/americanexperience/media/filer_public/67/d8/67d8e5ce-78fe-4b95-922a-bb669d0947d7/_cc_broken_arrows.pdf."Narrative Summaries of Accidents Involving U.S. Nuclear Weapons 1950-1980." The DOD defines this type of accident to be an unexpected event involving nuclear weapons or nuclear weapons components that results in any of the following:
  • Accidental or unauthorized launching, firing, or use, by U.S. forces or supported allied forces, of a nuclear-capable weapon system which could create the risk of an outbreak of war
  • Nuclear detonation
  • Non-nuclear detonation or burning of a nuclear weapon or radioactive weapon component, including a fully assembled nuclear weapon, an unassembled nuclear weapon, or a radioactive nuclear weapon component
  • Radioactive contamination
  • Seizure, theft, or loss of a nuclear weapon or radioactive nuclear weapon component, including jettisoning
  • Public hazard, actual or implied
The DOD list of Broken Arrow events came only after years of government silence surrounding nuclear accidents. As the nuclear complex grew after World War II, the DOD maintained a culture of secrecy related to nuclear weapons accidents unless they deemed it necessary to inform the public. From the DOD’s claim in 1958 that it was highly unlikely there could be an accident involving nuclear weapons, to the release of the list of known events in 1981, the DOD has shifted its view on what accidents should be deemed Broken Arrows. In this 1981 document, the DOD justifies the secrecy around Broken Arrows with the need to keep the locations of nuclear weapons classified; they only release specific information if the accident puts the public in any harm.

In this document, the DOD admits there have been other incidents surrounding nuclear weapons that they did not qualify as accidents, which suggests that “accidents” or Broken Arrows are determined by those who define these two terms. Various organizations believe there have been many more Broken Arrows than what the government has admitted. Gary Hanauer, "The Story Behind the Pentagon’s Broken Arrows: An Arrow is a Nuclear Weapon. A Broken Arrow is a Nuclear Disaster," Mother Jones 6, no. 3 (1981): 56-57.A 1960 Ohio State University paper claimed there have been 50 Broken Arrows between 1945-1960, while Newsweek in 1969 argued more than 60 Broken Arrows occurred before 1961. Some organizations claim this number is in the hundreds: Chuck Hansen, "The Oops List," Bulletin of the Atomic Scientists 56, no. 6 (2015): 65-66.in 1973 Sandia Laboratories stated 272 bombs were involved in incidents of impact during 1950-1968; a 1985 General Accounting Office study reported there had been 233 incidents involving nuclear weapons in the Navy between 1965 and 1983; and in 1989 Greenpeace released a list of 383 Broken Arrows that occurred between 1965 and 1977. Regardless of what other organizations have deemed to be Broken Arrows, the government’s list of 32 accidents remains the official list of Broken Arrows.

Black and white image of three white- and male-presenting people in military officers' uniforms pose behind a long and heavily dented hydrogen bomb on board a ship. A fourth man to the left of the other three wears civilian clothes and looks down at the bomb. Left to right are Sr. Don Antonio Velilla Manteca, chief of the Spanish Nuclear Energy Board in Palomares; Brigadier General Arturo Montel Touzet, Spanish coordinator for the search and recovery operation; Rear Admiral William S. Guest, commander of U.S. Navy Task Force 65; and Major General Delmar E. Wilson, commander of the Sixteenth Air Force.
Nuclear bomb recovered from at depth of 2,850 feet beneath the ocean following a midair collision over Palomares, Spain, 7 April 1966, Wikimedia Commons

Broken Arrows involving U.S. nuclear weapons have occurred both within the territorial United States and abroad. A 1961 nuclear accident in Goldsboro, North Carolina came closest to becoming a nuclear disaster. On a January day, a B-52 bomber broke apart mid-air, releasing two bombs. One bomb’s parachute deployed, while the other bomb crashed to the ground and shattered upon impact. An Air Force search of the surrounding land failed to locate a piece of the bomb containing uranium. In order to maintain confidentiality about the incident and ensure no one else would come across the missing piece, the Air Force bought an easement on the land requiring permission to dig. Gary Hanauer, "The Story Behind the Pentagon’s Broken Arrows: An Arrow is a Nuclear Weapon. A Broken Arrow is a Nuclear Disaster," Mother Jones 6, no. 3 (1981): 28.While the DOD insists that both bombs had no chance of detonating, other sources, including Dr. Ralph Lapp, former executive director of DOD’s Atomic Research Development Board, and Daniel Ellsberg, former Deputy Secretary of Defense, point out that the bomb that landed with its parachute had 5 out of 6 safety features triggered, meaning it was just one trigger away from detonating.

Stephen I. Schwartz, ed. Atomic Audit: The Costs and Consequences of U.S. Nuclear Weapons Since 1940 (Washington, DC: Brookings Institution Press, 1998), 408.A 1966 accident in Palomares, Spain is one of the most well-known Broken Arrows due to the extent of the damage and international impact. A B-52G bomber collided with a KC-135 aircraft as it was attempting to refuel at an altitude of 30,000 feet above the coast of Spain. Aboard the bomber were four hydrogen bombs that fell from the aircraft. One landed in a river bed, while another landed in the sea and took almost 3 months to find. The final two bombs detonated once they hit the ground, leaving craters 6-10 feet deep and releasing plutonium particles into the air and across the ground, affecting the nearby town of Palomares. The Spanish government demanded that the United States pay for cleanup and remove 1,400 tons of contaminated soil. The cleanup took three months and involved 1,700 U.S. and Spanish personnel. The Defense Nuclear Agency and the Junta de Energía Nuclear found that around 1 square mile of the farmland and village had been contaminated, and set up a monitoring system to keep track of the extent of the damage. In the end, the United States paid approximately $120 million for the cleanup and villagers’ settlements. Broken Arrows remain a contentious topic due to the DOD’s secrecy and highly selective definition of these accidents. While the military has thus far kept the accidents localized, there has always been a chance that an accident could have grave consequences, from loss of life and radiological contamination, to inadvertently triggering nuclear war.


U.S. Department of Defense. "Narrative Summaries of Accidents Involving U.S. Nuclear Weapons 1950-1980." Washington, DC: Government Printing Office, 1981. Accessed August 2, 2020.

Hanauer, Gary. “The Story Behind the Pentagon’s Broken Arrows: An Arrow is a Nuclear Weapon. A Broken Arrow is a Nuclear Disaster.” Mother Jones 6, no. 3 (1981): 23-28, 52-59.

Hansen, Chuck. “The Oops List.” Bulletin of the Atomic Scientists 56, no. 6 (2015): 64-66. DOI: 10.1080/00963402.2000.11457017

Schwartz, Stephen I., ed. Atomic Audit: The Costs and Consequences of U.S. Nuclear Weapons Since 1940. Washington, DC: Brookings Institution Press, 1998.


Last Updated:


Continue on "Deployment"