Clipper Endeavor Historical Background

On Good Friday, 11 April 1952, Clipper Endeavor (NC88899), a large commercial airliner, took off from Aeropuerto de Isla Grande, San Juan, Puerto Rico bound for New York’s Idlewild (later JFK) Airport. On board were 64 passengers, mostly Puerto Rican residents, headed to the US mainland in search of work or to celebrate the Easter holiday with family. Captain John C. Burn, a PAA veteran who started his career in flying boats, led the crew of five. Burn was perhaps best known to the public as the husband of glamorous singer-actress, Jane Froman. Ironically, the two had met and fallen in love as the result of a wartime crash nine years earlier.

The plane was originally built during World War II by Douglas Aircraft Company as a C-54B Skymaster military transport for the US Army Air Forces, then converted to civilian DC-4 configuration and sold to Pan American World Airways. It was christened Clipper Endeavor and assigned to the company’s Latin American Division, part of a massive peacetime boom in air travel that made flying accessible to the general public. A ticket on the regular air service between NYC and San Juan cost just $64 (one way) for an eight-hour flight.

Trouble started almost immediately after takeoff when two of the plane’s four engines (#3 and #4) lost power. Rapidly shedding altitude, Captain Burn struggled to keep Clipper Endeavor aloft and return to the airport but was forced to ditch in heavy seas a few miles offshore. Incredibly, everyone on board survived the impact. Yet relief swiftly turned to horror as water rushed inside the downed aircraft, which floated just “two or three minutes” before sinking from sight. 

Swift and heroic action by the US Coast Guard and Air Force rescued 17 people (12 passengers and all 5 crew) from the roiling seas and also recovered the bodies of an additional 13 victims. Survivors recounted heartbreaking tales of chaos and confusion from inside the flooding plane as the joyous holiday trip suddenly became a life and death struggle.  Many travelers found themselves unsure of what to do or paralyzed by fear of the large waves and sharks outside. Claiming a total of 52 lives, the disaster was the worst loss suffered by Pan Am up until that time and still ranks as the second deadliest aviation accident in the history of Puerto Rico. 

A Civil Aeronautics Board investigation report (dated 26 September 1952) attributed the probable cause of the crash not to the mysterious and fearsome waters of the Bermuda Triangle, but instead faulted “the company’s inadequate maintenance” and also found that “the captain demonstrated questionable flying technique under the existing conditions.” The Board went on to propose numerous regulation amendments including a provision that “each air carrier shall establish procedures for orally briefing passengers as to the location and operation of life vests and emergency exits and the location of life rafts.”

The result was the pre-flight safety briefing, that short and concise lecture instructing airplane passengers about what to do “in the unlikely event of a water landing.”  A ritual instantly familiar to anyone who has ever traveled by air, it  is also a lasting legacy of the tragic day when Pan American World Airways Flight 526A fell into the sea.

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