Throughout the Cold War, tens of thousands of nuclear weapons were built and deployed on land, sea, and air. In the vast majority of cases, these highly potent weapons were subject to the strictest of safety conditions.
However, accidents do happen. Some of the weapons involved are still lost to this day.
How many nuclear weapons are missing?
A "Broken Arrow" is an unexpected event that results in the accidental launching, firing, detonating, theft, or loss of a nuclear weapon. These events are, worryingly, more numerous than you might think. Since around 1950, somewhere in the order of thirty-two nuclear incidents occurred which could be classed as Broken Arrow.
The United States has lost somewhere in the order of 6, or so, but this is only the tip of the iceberg. Other nuclear powers, like the former Soviet Union, have also lost their fair share.
Otfried Nassauer (d. 2020), an expert on nuclear armament and former director of the Berlin Information Center for Transatlantic Security, told Der Spiegel in a 2008 interview, "It is believed that up to 50 nuclear weapons worldwide were lost during the Cold War." He believed that most of these weapons are currently lying in various locations on the seafloor.
Of these, some have been recovered, but the others were either destroyed in the incidents, or are yet to be retrieved, if ever. Lets' take a closer look at some of them.
1. One of them lies off the coast of British Columbia
On the 13th of February 1950, a B-36 carrying nuclear warheads was en route from Eielson Air Force Base to Carswell Air Force Base on a training mission. The warhead in question, a Mark IV atomic bomb, was being carried in a dummy capsule.
The weapon in question was roughly comparable to the nuke dropped on Nagasaki in 1945. However, it was not, technically speaking, a viable nuclear bomb. It contained large amounts of uranium, and also lots of conventional high explosives, but lacked the plutonium core necessary to actually trigger a nuclear blast.
The test flight was meant to simulate a bombing run on a major enemy city. The B-36 was slated to fly from Alaska to Montana, then down to San Francisco, its “target,” before landing in Carswell Air Force Base in Texas.
Soon after takeoff, ice began to accumulate on the bomber’s fuselage. The excess weight put tremendous strain on the engines, three of which caught fire and had to be shut down. The aircraft was at around 12,000 feet (3,658 m) at the time but with only three functioning engines, the plane began to rapidly lose altitude.
The engine loss also hindered the aircraft from maintaining level flight for very long. To prevent the situation from becoming even more serious, and following military protocol to deny the weapon to potential hostile forces, the crew of the B-36 jettisoned their payload into the Pacific Ocean at around 8,000 feet (2,438 m) altitude.
The bomb's conventional explosives were detonated to destroy the bomb. A bright flash was observed, followed by a large sound and a shock wave — but not large enough from what would be expected from a thermonuclear explosion. It appeared that only the high explosive material on the bomb detonated, meaning the nuclear warhead likely survived.
As for the crew of the aircraft, they managed to coax their stricken B-26 to Princess Royal Island where they bailed out. The wreckage of the bomber was later discovered on Vancouver Island.
The failing plane’s autopilot was set to steer it on a course toward the open ocean while the crew parachuted into the sea over Princess Royal Island on the coast of British Columbia. The abandoned B-36 eventually crashed into the flank of remote Mount Kologet, in Canada, where it was found three years later. Twelve of the 17 crew members were recovered alive, including one man found dangling upside-down in a tree.
This would be the first of, sadly, many "Broken Arrow" incidents over the coming decades.
2. There are some nukes lying somewhere in the Meditteranean Sea
On March 10th, 1956, a Boeing B-47E "Startojet" carrying two capsules containing nuclear weapon material took off from MacDill Air Force Base in Florida. It was scheduled to fly, non-stop, to the Ben Guerir Air Base in Morroco.
The aircraft managed to complete the first of its two planned mid-air refuelings without any issues and continued on its final leg to Morocco. Later, the aircraft began to descend through a bank of solid clouds to begin its second refueling at around 14,000 feet (4,300m), never rendezvoused with the tanker, as planned.
After days and weeks of extensive search and rescue attempts including by the British Royal Navy, French and Spanish-Moroccan army assets, no debris from the aircraft, or sign of its crew was ever found. Crew members were Captain Robert H. Hodgin, Captain Gordon M. Insley, and 2nd Lt. Ronald L. Kurtz.
To this day, the location of the downed warbird and her payload is still unknown. Presumably, the aircraft must have downed somewhere in the Mediterranean Sea.
The aircraft's last known position was somewhere southeast of Port Say, an Algerian coastal village near the Moroccan frontier. A French news agency reported that the plane may have exploded in flight near Sebatna in eastern French Morocco, but this could not be confirmed by U.S. investigators.
Thankfully, the nuclear payload on board was not a viable nuclear weapon, so could not have detonated. However, they must still be out there somewhere, ready to be discovered in the future.
3. There are a couple more nukes somewhere in the Atlantic near New Jersey
On the 28th of July, 1957, an American C-124 was en route to Europe from Dover Air Force Base in Delaware. She was carrying three nuclear weapons and one nuclear core on takeoff. Mid-flight, the plane developed some very serious engine problems, the plane was forced to turn back, and maximum power was applied to the remaining engines to compensate and save the aircraft.
Despite the efforts of the pilots, level flight could not be maintained and the decision was made to jettison the payload to reduce weight. An emergency landing of an aircraft like the C-124 would have likely proved disastrous, resulting in the loss of the aircraft and all hands.
Non-essential equipment would have gone first, followed by excess fuel, but with the plane still losing altitude, and still 100 miles (160 km) off the coast of New Jersey, there was no choice left but to jettison the atomic bombs as well.
The first weapon was ejected at 4,500 feet (1,372 m), with the second released at 2,500 feet (762 m). This proved enough to allow the C-124 to regain altitude and limp back to the nearest airbase.
Neither weapon was reported as detonating, but it was later surmised that they were damaged by the impact of the ocean surface. Since they were not destroyed outright, the weapons must have sunk to the seafloor fairly quickly.
The C-124, and her crew, managed to land safely at an airfield in the vicinity of Atlantic City, New Jersey, with the remaining weapon and the nuclear capsule aboard.
To date, the missing weapons have never been located or recovered. They are thought to be somewhere roughly 100 miles of New Jersey, but no one can be entirely sure.
4. It appears another nuke is lying in Wassaw Sound near Tybee Island
Another "Broken Arrow" incident occurred on the 5th of February 1958. Called the "Tybee Island Mid-air Collision", a 7,600lb (3.400 kg) Mark XV nuclear bomb was lost in the waters off Tybee Island (near Savannah), in Georgia.
At the time, a B-47 bomber was on a simulated combat mission from Homestead Air Force Base in Florida. The plane was carrying a bomb containing highly enriched uranium and 400 pounds of high explosives (181 kg), but the plutonium core had been replaced with a dummy lead core.
The simulation included a number of F-86 fighter aircraft. One of these craft failed to spot the bomber on the radar. The fighter jet collided with the B-47 at 38,000 feet (11.58 km), heavily damaging the bomber's fuel tanks and putting a massive hole in the wing.
The F-86 was severely damaged and crashed soon after, thankfully, the pilot managed to safely eject. The bomber, on the other hand, managed to remain airborne and plummetted from 38,000 feet (12,000 m) to around 18,000 feet (5,500 m) before the pilot managed to regain control.
Worried the bomb would break loose on landing, and that the plane was too heavy to make it back safely, the crew jettisoned their payload to help save the plane, and prevent accidental detonation should the aircraft crash. The bomb was released at around 7,200 feet (2,200 m) into the waters off Tybee Island.
No explosion was observed, and the bomb presumably sunk intact. The B-47 managed to touch down safely at Hunter Air Force Base.
Despite extensive contemporary and more modern search efforts, the resting place of the bomb is still unknown. Constant environmental surveillance has not noted any elevated radioactivity for the area above natural levels, so thankfully, the environmental impact appears negligible, for the moment at least.
5. One nuke is still buried under some farmland in North Carolina
On the morning of January 24th, 1961, 8 servicemen, and a payload of two Mark 39 thermonuclear bombs were on patrol on a B-52 Stratofortress over Goldsboro, North Carolina. The patrol was part of an insurance policy in case of a surprise Soviet nuclear attack. The bomber would have been tasked with releasing its payload over Soviet targets should the worst happen.
During a scheduled mid-air refueling, the tanker crew warned the crew that their B-52 had a fuel leak and aborted the operation. The leak progressively became worse, and the B-52 was ordered to return to Seymour Johnson Air Force Base.
As the aircraft descended from 10,000 feet (3,000 m) on approach, the pilots lost control and ordered the crew to abandon the aircraft. Shortly after, the bomber began to break up mid-air, losing control of its bomb bay doors, and its two nuclear bombs actually separated from the aircraft.
One bomb safely parachuted to the ground and snagged on a tree where military crews quickly found it.
However, the parachute of the other bomb failed, causing it to slam into a swampy, muddy field and break into pieces. It took about a week of digging to find most of its parts. On studying the bomb, crews learned that six out of seven steps in the bomb's automated activation sequence had been completed, meaning it was very close to detonating a thermonuclear explosion. Only one trigger stopped a blast — and that switch was set to "ARM", yet somehow it failed to detonate the bomb.
If it had gone off, as Ed Pilkington told the Guardian back in 2013, "lethal fallout could have been deposited over Washington, Baltimore, Philadelphia, and as far north as New York City". This would have put millions of lives at risk.
However, part of the second bomb was never recovered. Its secondary core remains buried in the mud, possibly up to 200 feet (~61 m) deep. The missing secondary is thought to be made mostly of non-weapons-grade uranium-238 and some weapons-grade uranium-235. The United States Army Corps of Engineers would later purchase a circular easement over the designated location of the lost component that prevents building on the land, but does allow farming.
6. The 1965 Philippine Sea A-4 crash took one weapon to Davy Jones' Locker in the Pacific
On the 5th of December, 1965, the United States aircraft carrier, the USS Ticonderoga, was on maneuvers in the Pacific Ocean roughly 68 miles (59 nautical miles/109 km) from Kikai Island, Kagoshima Prefecture, Japan. On her deck was a Douglas A-4E "Skyhawk" attack jet aircraft armed with one B43 nuclear weapon.
The B43 was a variable yield (so-called "dial-a-yield") air-dropped, thermonuclear bomb equipped on a wide variety of fighter-bomber aircraft in the 1960s. Roughly 2,000 were made, and some parachute-retarded descent versions were also produced. This particular bomb had a 1 megaton yield.
31 days after the Ticonderoga's departure from the U.S. Naval Base Subic Bay, in the Philipines, the aircraft in question was being rolled from hanger 2 to number 2 aircraft elevator as part of a training exercise. An accident occurred, and the aircraft, including the weapon and pilot, fell over the side of the aircraft carrier into the sea below.
The aircraft quickly sank, preventing the pilot, Lieutenant (junior grade) Douglas M. Webster, from escaping. The waters in the area are roughly 16,000 feet (4,900 m) deep, and the aircraft, remains of the pilot, and the weapon has never been recovered to this day.
Details of the accident were not publically revealed until 1989.
7. The U.S. lost a nuclear-powered submarine in 1968
In the late-1960s, SSN-589 USS Scorpion, a Skipjack-class nuclear submarine was on deployments in the Meditteranean Sea. Operating with the 6th fleet until May of that year, she then headed west for a home port in Norfolk, Virginia on the 16th of May.
USS Scorpion was then detailed to observe Soviet naval activities in the Atlantic in the vicinity of the Azores. With this completed, Scorpion prepared to head back to Naval Station Norfolk expected to arrive on the 20th of May, but she never made it.
At the time, she had a crew complement of 99, and two nuclear-tipped torpedoes, as well as her nuclear propulsion systems.
For a period of time between the 20th and 21st of May, the Scorpion attempted to send radio signals to Naval Station Rota in Spain but was only able to reach a Navy communications station in Nea Makri, Greece who attempted to forward the messages to the U.S.
Six days later she was officially reported as missing, and a search and rescue mission was launched. Her wreck was found at a depth of 10,800 feet (3,300 meters) about 320 nautical miles (592 km) south of the Azores. No survivors were found, and, presumably, she still has her nuclear-armed torpedoes onboard.
To this day, it is still not entirely clear why she faltered and sank.
8. In 1968, a Soviet submarine took several nukes to the seafloor
On the 11th of April 1968, the Soviet diesel-powered K-129 submarine was on maneuvers in the Pacific Ocean. Onboard were three nuclear-armed ballistic missiles, as well as, various nuclear-armed torpedoes, and her crew of ninety-eight.
For some unknown reason, the submarine had some serious technical issues, and disappeared, presumably sunk taking her crew and payload to the ocean depths.
The Soviet Union lacked the technology to attempt recovery at the time and left the stricken submarine to its fate. However, the sunken sub offered a prime opportunity for the United States to attempt to gather some important Cold War intel.
The Central Intelligence Agency (CIA) believed they could attempt recovery of some, or all, of the submarine that lay at depths of something like 3 miles (4.82 km). To this end, a custom-built ship, the Hughes Glomar Explorer, was commissioned and built under the codename "Project Azorian".
Disguised as an ocean mining vessel, the ship was sent to find the wreck and salvage what they could. Apparently, some parts of the submarine were successfully salvaged but it is unclear whether or not all of the nuclear weapons were also lifted from the seafloor.
9. A B-52 crashed in Greenland losing a nuke in 1968
On the 21st of January, 1968, a B-52 bomber of the United States Air Force (USAF) was on a routine "Chrome Dome" alert mission over Baffin Bay, Greenland. Onboard she carried four B28FI thermonuclear bombs and her crew.
"Chrome Dome" was an airborne alert program that required twelve B-52 bombers to be aloft at any one time just outside Soviet airspace, and acted as a significant nuclear deterrent to prevent a Soviet "First Strike" event.
It was as part of this grand deterrent strategy that one B-52G, callsign "HOBO 28" was loitering over Thule, nearby the Baffin Bay on Greenland. It was a particularly cold day and the crew struggled to keep warm and decided to open an engine bleed valve to direct additional heat to the cabin air conditioning from the engine manifold.
Soon the cabin became uncomfortably hot, and some cushions stowed in front of a heating vent managed to combust. After failed attempts to put out the fires with onboard fire extinguishers, smoke began to fill the cabin, and the crew was forced to attempt an emergency landing.
It soon became clear it would not be possible to land the aircraft safely, and the crew ejected out of the aircraft. One crew member suffered a fatal head injury during the escape.
Left pilotless, the flaming B-52 crashed onto sea ice in North Star Bay at a relatively shallow angle, a few miles west of Thule Airbase. On impact, the conventional explosive components of the four 1.1 megaton nuclear bombs detonated, spreading parts of the B-52 and radioactive material over a wide area.
Thankfully no nuclear explosions were triggered, but the extreme heat from the explosion and burned jet fuel melted the ice, resulting in some wreckage and munitions sinking into the ocean below.
After cleaning up the mess (and reconstructing the bomb fragments), experts noted that one warhead was missing. Apparently, it had drilled its way into the ice of North Star Bay and remains there to this day.
10. Another Soviet submarine sank in the 1970s carrying some nukes
On the 12th of April, 1970, a Soviet Type 627 nuclear "November"-class submarine was traveling through the Bay of Biscay. A notoriously dangerous waterway for submarines throughout the First World War, these old wrecks would be joined by a newcomer very soon.
The submarine, K-8, was powered by two nuclear reactors and also had a payload of four nuclear-tipped torpedoes, and first entered active service in late-1960. She was on maneuvers as part of a large Soviet naval exercise designed to display the might of the Soviet Navy, when, out of the blue, the K-8 suffered from two uncontrollable fires.
This caused the two reactors to shut down, forcing the sub to surface. A rescue attempt was made, but a combination of bad weather and loss of power made the mission far too difficult. Tragically, the K-8 sunk with forty crew members trapped inside, as well as her potent payload.
To date, her nuclear torpedoes still remain inside her on the sea bottom.
11. The Soviets lost some more nuclear weapons in the mid-1980s
In the mid-1980s, a Soviet "Yankee 1" 667A Navaga-class nuclear-powered ballistic missile submarine was on patrol several hundred miles east of Bermuda. Called K-219, onboard were the ship's twin nuclear reactor power plants and 16 ballistic missiles, each armed with two nuclear warheads. As well as her crew of around 120, of course.
K-219 was 15 years old at the time, and she was deployed on a routine Cold War nuclear deterrence patrol in the Atlantic.
All seemed to be well until, for unknown reasons, a massive explosion and fire erupted in one of its missile tubes. Later investigations discovered that the likely cause was a failed seal of one of the missiles tubes. This allowed water to rush in, rupturing the contained missile's fuel tanks, ultimately allowing it to combust.
The submarine crew put the submarine into a "nuclear safe" state and surfaced the vessel using her battery power alone. Later, a Russian freighter arrived to bring the submarine home under tow while the crew attempted to contain flooding and gas leaks.
Sadly, these attempts failed and overcame the vessel. She sank on October the 6th to the bottom of the Hatteras Abyssal Plain at a depth of about 18,000 feet (6,000 m). None of her nuclear weapons were recovered, but it is believed that all of the crew were rescued.
12. The Soviets lost another nuclear submarine in the late-1980s
On the 7th of April, 1989, the Komsomolez (a Project-685 Plavnik Soviet nuclear-powered, and armed, attack submarine) was on patrol several hundred miles from the Norwegian coast. She had a crew of 69, and a payload of two nuclear-armed torpedoes onboard.
Also known as K-278, she was the only example of her class and something of a technological feat. In August 1984, she set a record for reaching a depth of 3,350 feet (1,020 m) in the Norwegian Sea.
Designed to evaluate the technology needed for a fourth-generation submarine, she officially entered service in 1983. During her third operational patrol of the Arctic Ocean, a series and uncontrollable fires broke out in her aft compartments.
Despite this very serious problem, the K-278 was able to surface and stay afloat for around 5 hours before sinking to a depth of 5,500 feet (1,700 meters) in the North Atlantic Ocean.
Of her full complement of crew, 42 were killed in the accident. She also took her nuclear reactors and nuclear-warhead armed torpedoes with her.
These have never been recovered. After the wreck was discovered, it was found that she was leaking small amounts of plutonium into the sea.
This triggered a mission to reach the wreck and seal her damaged hull to reduce its impact on the environment.
And that, nuke-nerds, is your lot for today.
As worrying as this information may or may not be, the environmental impact of these lost nuclear weapons is widely considered to be negligible. Especially those that lie at great depths below the waves.
They are also largely safe from recovery by bad actors as most are in some of the most inhospitable and difficult to reach places in the world. After all, if official military attempts can't get to them, who can?