On Good Friday, April 11 1952, a Pan American Douglas DC-4 named Clipper Endeavor took off from San Juan in Puerto Rico, bound for New York. On board were 64 passengers including six infants, plus five crew.

The flight lasted less than nine minutes before two engines lost power. Unable to make it back to the airport, the captain ditched the plane in the Atlantic Ocean, roughly 11 miles northwest of San Juan’s Isla Grande Airport.

Remarkably, all 69 people on board survived the impact. What killed 52 of them was what happened afterwards.

The airframe broke apart and began to sink, and in the ensuing chaos, many passengers refused the captain’s order to get out, remaining buckled into their seats. Investigators recorded drowning as the cause for almost all of the deaths.

The pilot told air crash investigators that he had forced some of the passengers into the water. However, the language barrier between the crew and the mostly Puerto Rican passengers had made communication harder – as did their reported fear of sharks in the water.

For 74 years, the wreckage remained hidden under 2,000 feet of water off Puerto Rico’s coast – until an uncrewed underwater vehicle owned by marine survey company Deep Sea Vision located it in June 2026.

As a former commercial airline pilot, the story of this tragedy holds particular interest for me – in particular, the enormous impact it had on how airline safety procedures are still done today. According to Josh Gates, a Discovery Channel presenter who was part of the search team: “It is an accident that fundamentally reshaped aviation as we know it.”

The critical 90........

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