What happened
On April 11, 1952, a Pan American World Airways DC-4 departed San Juan at 12:11 for New York. During the initial climb phase, shortly after reaching an altitude of approximately 250 feet and retracting the landing gear, the crew identified a significant drop in oil pressure accompanied by rising oil temperature in the number three engine. The flight crew notified the San Juan tower of their intention to return to the airport.
In an attempt to manage the failure, the crew feathered the propeller of the third engine and increased power on the remaining engines. However, as the aircraft climbed toward 350 feet, the number four engine began backfiring and running roughly. Despite attempts to stabilize the fourth engine by reducing manifold pressure, the engine continued to experience intermittent power issues.
As the aircraft lost altitude, the crew attempted to maintain a course parallel to the coastline and increased power on engines one and two. To reduce weight, the crew opened all fuel dump valves. By 12:19, the captain informed the tower that a ditching might be necessary. At 12:20, an observing C-47 pilot reported seeing the aircraft attempting to land on the water. The DC-4 subsequently made contact with the sea at approximately 120 miles per hour. Following the impact, the crew and passengers attempted to evacuate; however, the aircraft sank roughly three minutes after ditching.
Findings
Investigations into the accident revealed that the primary cause was inadequate engine maintenance by the operator, which left the number three engine in a condition that led to its failure immediately after takeoff. Additionally, the pilot's decision to attempt a climb without utilizing all available power following the loss of the third engine contributed to a nose-high attitude and a progressive loss of airspeed. It was also noted that metal particles had been previously discovered in the nose section of the third engine, yet the engine was not replaced prior to departure.