On the night of February 13, 1950, a Convair B-36B “Peacemaker” carrying a nuclear payload was returning from a practice bombing run when poor weather caused three of its six engines to fail. With the aircraft unable to continue, the crew jettisoned its Mark 4 “Fat Man” nuclear bomb into the Pacific Ocean before bailing out. The B-36 continued, unmanned until it crashed into Mount Kaloget, British Columbia. The Air Force insists that the bomb’s detonation core was replaced with a dummy practice core before being dropped; however, this cannot be confirmed because the weapon has never been recovered.

It’s unsettling to think that a potentially armed nuclear weapon has just been sitting unattended somewhere off the coast of Canada for the last 73 years. Even more unsettling is that at least five other Broken Arrow events resulted in “lost” nuclear weapons, and those are just the ones the US Government admits to.

The next occurred on March 10, 1956, when a Boeing B-47 Stratojet took off from Macdill Airforce Base, Florida, en route to Ben Guerir Airbase, Morocco. After completing its first midair refueling, it lost contact with the tanker crew shortly before its second refueling. The Stratojet’s last known location was about 90 miles southwest of Oran. No trace of the aircraft was ever found. While there was no possibility of a nuclear detonation, the B-47 was carrying two nuclear cores that, in the wrong hands, could be highly problematic.

Two years later, another B-47, this time on a practice bombing run, was involved in a midair collision with an F-86 near Savanah, Georgia. After making three attempts to land, the crew received authorization to jettison its nuclear bomb so as not to risk detonation during a crash landing. The bomb was dropped in Wassa Sound, off Tybee Beach, and was never recovered. After dropping the weapon, the B-47 landed safely at Hunter Airforce Base. Again, the Air Force reports that the bomb did not possess its nuclear capsule. Even so, a conventional explosion would still be possible.

Then, of course, there was the time that the Air Force almost erased North Carolina from the map. It happened on January 24, 1961, when a fuel leak on a Boeing B-52 Stratofortress led to the aircraft breaking apart over Goldsboro, North Carolina. Five of the eight crewmembers parachuted to safety, though the aircraft’s two four-megaton Mark-39 nuclear bombs broke free and fell to earth. One of them was found hanging in a tree, its parachute having deployed. The other impacted a field at approximately 700 miles per hour and was obliterated, burying itself about 180 feet into the earth. The intact bomb was recovered, as was the nuclear core of the other. A report declassified in 2013 revealed the chilling fact that both bombs had triggered 3 out of 4 of its arming devices.

On December 5, 1965, the aircraft carrier USS Ticonderoga was participating in a training exercise in Japanese waters about 70 miles from Kikai Island. While transporting an AE-4 Sky Hawk from the flight elevator to the deck, the aircraft somehow fell overboard. The pilot and at least 1 B43 nuclear weapon were lost at a depth of approximately 16,000 feet and never recovered. Details of the event remain murky, and it wasn’t until 1989 that the US Government confirmed that an atomic bomb was lost in Japanese territory.

The final unrecovered nuclear weapons are those of the nuclear submarine USS Scorpion, which mysteriously went missing in May of 1968. Eventually, the wreck of the Scorpion was found; tragically, the vessel sank with the loss of all 99 of her crew. The Scorpion’s two nuclear warheads and nuclear reactor remain at the bottom of the North Atlantic at approximately 9,800 feet.

The optimist in me might point out that it’s been well over fifty years since we’ve lost a nuclear weapon. However, the realist in me knows better. It’s much more likely that these kinds of “whoopsies” are aggressively covered up and classified these days. As for the known bombs lost in the world, it’s incredibly unlikely, if not impossible, for any of them to detonate. At least, that’s what we’re told. I suppose it’s better to go with that if you like sleeping at night.

Before you get too comfortable, remember the United States is not the only nuclear power. It has been rumored that upwards of 100 “suitcase” nuclear bombs remain unaccounted for after the breakup of the Soviet Union. In fact, it is unknown whether their entire arsenal of conventional nuclear weapons is accounted for, though it is widely believed that vast amounts of nuclear material did go missing. Then, of course, there is the possibility of their own version of Broken Arrows.