1952 · Aviation Mysteries
Category: Historical Mysteries
Start: 1952-04-11 · End: 2026-07-21
Location: Atlantic Ocean off San Juan, Puerto Rico
On Good Friday, April 11, 1952, Pan American World Airways Flight 526A — a Boeing 377 Stratocruiser named the Clipper Endeavor (registration NC88899) — departed San Juan's Aeropuerto de Isla Grande bound for New York's Idlewild (now JFK) Airport. On board were 64 passengers, most of them Puerto Rican residents traveling to the U.S. mainland for work or to celebrate Easter with family, and a crew of five. Shortly after takeoff, engine number four suffered a catastrophic failure. The propeller could not be feathered, drag mounted, and Captain John C. Burn attempted to return to San Juan. The Stratocruiser could not maintain altitude and ditched in the Atlantic. Fifty-two people died; seventeen survived. The disaster prompted sweeping reforms in transoceanic aviation safety, including new rules on propeller feathering, over-water flight procedures, and life-raft standards. The wreck site was never located — until 2026. After a multi-year search led by the Air/Sea Heritage Foundation (documented in part on Discovery's "Expedition Unknown"), the resting place of the Clipper Endeavor was confirmed on the Atlantic floor roughly 2,000 feet below the surface. CNN and TODAY announced the di…
Seventy-four years later, they are found.