What is the Bermuda Triangle? The legend and the evidence

The Bermuda Triangle is a stretch of the western Atlantic Ocean, usually drawn between Miami, Bermuda and San Juan in Puerto Rico, where ships and aircraft are said to disappear without explanation. It is a legend, not a place on any official map. When researchers checked the famous cases against records, most had ordinary causes, and neither insurers nor the US Coast Guard find more losses there than in other heavily traveled waters.

In short

• The "triangle" was invented by magazine writers between 1950 and 1964 and made famous by a bestselling book in 1974.
• A librarian who checked the cases one by one in 1975 found storms, accidents, exaggerations, and some incidents that happened far away or not at all.
• The region sees heavy traffic and violent weather, so it has losses, but not more than expected; there is nothing unusual left to explain.

Where is the Bermuda Triangle?

There is no agreed answer, which is the first clue. Writers have drawn it with different corners, and the area they describe has ranged from about 1.3 million to 3.9 million square kilometers, according to the Wikipedia account of the legend. The most common version uses Miami, Bermuda and San Juan. The US Board on Geographic Names does not recognize the name and keeps no official boundaries for it, as NOAA's Ocean Service notes.

The water inside is some of the busiest in the world. It lies on the routes between North America, the Caribbean, the Gulf of Mexico and Europe, and it is crossed constantly by cargo ships, cruise ships, yachts, fishing boats and planes.

How did the legend start?

The legend was built in steps, each writer adding to the last:

Year	What happened
1950	E. V. W. Jones writes an Associated Press article about ships and planes lost in the area, the first to suggest a pattern
1952	George X. Sand, in Fate magazine, is the first to draw the area as a triangle
1964	Vincent Gaddis's article "The Deadly Bermuda Triangle" in Argosy gives it its name and claims losses going back to at least 1840
1974	Charles Berlitz's book The Bermuda Triangle becomes a bestseller, linking the losses to Atlantis, strange energies and other theories
1975	Larry Kusche publishes The Bermuda Triangle Mystery: Solved, checking each case against records

The stories leaned on a few real losses. The best known is Flight 19: on 5 December 1945, five US Navy torpedo bombers on a training flight from Fort Lauderdale became lost and disappeared with all 14 airmen. A flying boat sent to search for them was lost with its 13 crew; a passing tanker reported flames from an apparent explosion that evening. Radio fragments pointed to compass failure and a disoriented flight leader, Lieutenant Charles Taylor, leading the planes away from land until they ran out of fuel and ditched as bad weather moved in, according to the Naval History and Heritage Command. The board of inquiry blamed Taylor's confusion. His mother challenged that, since nothing was ever found, and a later Navy board cleared him with the finding that "the cause of the accident remains unknown." The legend quotes that phrase as if it hinted at a mystery; it records only that there was no wreckage to examine.

The other famous case, the Navy collier USS Cyclops, vanished with 306 people in March 1918 after leaving Barbados. It was overloaded with manganese ore and running on one engine, and structural failure is considered the most likely cause.

What did checking the records show?

Larry Kusche was a research librarian at Arizona State University who kept getting questions from students about the triangle. With a colleague he wrote hundreds of letters to official sources and gathered what records existed for each case. According to the summary of his work, he found that most incidents had been caused by storms or accidents, that many happened outside the triangle, and that some could not be shown to have happened at all. He called the whole thing a "manufactured mystery," the result of poor research and reporting, and the occasional deliberate falsification of facts.

A pattern runs through the cases he checked. The stories dropped the weather report, moved the wreck, left out that wreckage was later found, or quoted another author's version instead of the original record. Each retelling made the case more mysterious than the last.

Do ships really disappear there more often?

No. What matters is not how many losses happen in an area but how many happen for each ship or plane that passes through. The legend counts losses; it never divides by traffic.

Worked example: counting losses fairly

These numbers are invented to show the reasoning, not real statistics.

1. Suppose a busy sea sees 100,000 voyages a year and 20 of them end in a loss. That is 20 ÷ 100,000 = 1 loss in every 5,000 voyages.
2. Suppose a quiet sea sees 10,000 voyages and 2 losses. That is 2 ÷ 10,000 = also 1 in every 5,000.
3. The busy sea has ten times as many wrecks to write about, and exactly the same danger.
4. Now pick only the losses with no wreck found, from only the busy sea, over 100 years, and the list looks long and frightening. It says nothing about risk.

When the people with real money at stake looked, they found nothing. Asked for a television documentary whether an unusually large number of ships had sunk there, the insurance market Lloyd's of London found that they had not, and it does not charge higher rates for crossing the area. The US Coast Guard's inquiries contradict many of the cases the books describe. A 2013 study by the conservation group WWF of the ten most dangerous waters for shipping did not include it. NOAA states plainly that there is no evidence that mysterious disappearances occur with any greater frequency in the Bermuda Triangle than in any other large, heavily traveled area of ocean.

The region does have real hazards, and they explain its real losses. Most Atlantic tropical storms and hurricanes pass through it. The Gulf Stream, a fast, warm current, can whip up sudden rough weather and carry wreckage away quickly. Shallow banks around the islands catch boats, and inexperienced sailors are common in such busy, pleasant waters. NOAA also notes that a compass there has at times pointed to true north rather than magnetic north. That happens only along a line that drifts over the decades as Earth's magnetic field, generated by the churning iron of the outer core described in the note on what the Earth is made of, slowly changes; everywhere else the two differ, and navigators correct for it as a matter of routine.

Why do theories like methane bubbles miss the point?

Explanations such as giant methane bubbles from the seafloor or rogue waves are often offered to "solve" the triangle. They answer the wrong question. Some of these effects are real phenomena in the ocean, but there is no unusual loss rate in the triangle for them to explain. When the pattern isn't there, no special cause is needed. That is Occam's razor at work: the ordinary causes, storms, currents and human error, already account for the evidence.

How can you tell if a mystery is real?

The Bermuda Triangle is a near-perfect lesson in critical thinking. The same checks work on any claim of a strange pattern:

• Ask for the rate, not the count. Losses per voyage, cases per person, not a list of examples.
• Find the original record. A newspaper report, an inquiry, a weather log. If every source quotes another book, that is a warning.
• Check that the cases belong. Did each happen where and when the story says?
• Look for the missing cases. The legend collects the losses with no wreckage and forgets the millions of safe crossings, the same error behind survivorship bias.
• Ask what would count against it. A claim that survives any evidence, because the area can be redrawn to include every new loss, is not a claim about the world at all.

Check yourself

• Without looking back: why does a long list of losses in a busy sea tell you nothing about whether that sea is dangerous?
• What did Larry Kusche do that the earlier writers hadn't, and what did he find?
• Why do methane bubbles and rogue waves fail as explanations for the Bermuda Triangle?

Sources

• Is there something strange about the Bermuda Triangle? — NOAA National Ocean Service
• Bermuda Triangle — Wikipedia
• Lawrence David Kusche — Wikipedia
• The disappearance of Flight 19 and Training 49, 5 December 1945 — Naval History and Heritage Command, 2021