What happened
On a scheduled flight from Agana to Ulithi Atoll, an aircraft carrying 25 passengers and five crew members experienced mechanical difficulties shortly after departure. Approximately ten minutes into the flight, while cruising at 6,000 feet with a speed of 180 knots, the crew identified an oil leak in the right engine. Although the situation was initially managed, subsequent fluctuations in oil pressure prompted the captain to initiate an emergency return to Andersen Airbase.
During the approach, the right engine was shut down and the propeller was feathered. The aircraft struggled to maintain sufficient altitude, leading the crew to instruct passengers to jettison cargo in an attempt to lighten the load. Despite these efforts, the plane continued to descend. At 1141LT, the captain performed a ditching maneuver approximately 13 km southwest of the Guam coast. The aircraft settled on the water's surface, and while occupants successfully evacuated into life rafts, the plane sank roughly ten minutes later.
Of the 30 people on board, 28 survivors were rescued about an hour after the incident, though many sustained injuries. Tragically, there were 2 fatalities, consisting of one passenger and the flight engineer who drowned during the event.
Findings
Investigations determined that a malfunction or leak within the starboard engine caused significant issues, including low oil pressure warnings in the cockpit and a subsequent propeller overspeed.