What happened
During a routine maritime patrol flight, the aircraft came under attack from enemy forces. The plane was targeted by a Japanese Nakajima Ki-27 fighter, which successfully engaged the seaplane. Following the engagement, the crew attempted to maintain control of the aircraft but were forced to reduce altitude significantly. Unable to continue flight operations, the crew executed an emergency ditching maneuver in the waters off Sumatra. The seaplane subsequently sank beneath the surface. Despite the severity of the attack and the loss of the airframe, all occupants survived the incident.
Findings
The official investigation concluded that the primary cause of the accident was the engagement by hostile forces. The aircraft was shot down by a Japanese fighter, leading to the necessary ditching in international waters near Sumatra.