What happened
While operating en route, the flight crew was compelled to execute an emergency landing procedure due to circumstances requiring immediate action. Unable to reach a suitable runway or safe landing zone, the team opted to ditch the aircraft in the water off the coast of Yawata.
Upon impact with the surface, the structural integrity of the seaplane failed completely, causing the airframe to disintegrate. The violent breakup resulted in significant casualties among the personnel on board.
Findings
The incident resulted in four fatalities and one injury among the crew members. The immediate cause of the loss was the catastrophic structural failure of the aircraft during the water impact phase of the emergency ditching.