Investigation Summary
The flight departed Port Moresby at 10:53 local time for a short trip to Kokoda. As the aircraft approached the Kokoda Gap, a mountain pass frequently affected by rapid weather changes, the crew encountered heavy cloud cover. Witnesses on the ground reported hearing the aircraft fly low over Isurava village before a loud impact was heard. Because the Twin Otter was not equipped with a Cockpit Voice Recorder (CVR) or Flight Data Recorder (FDR), investigators relied on a GPS tracking device found in the wreckage to reconstruct the flight path. The data showed the aircraft was descending through the gap when it struck a mountain at an altitude of approximately 5,774 feet. The investigation highlighted that while the flight was planned under Instrument Flight Rules (IFR), the approach to Kokoda required visual reference, which was impossible given the cloud base. Furthermore, the First Officer was not qualified for IFR flight, and post-mortem examinations revealed he suffered from significant undiagnosed coronary artery disease, though it could not be proven if a medical event contributed to the crash.
Final Conclusions
The Papua New Guinea Accident Investigation Commission (AIC) concluded that the probable cause was Controlled Flight Into Terrain (CFIT). The crew attempted to maintain visual reference while descending through the Kokoda Gap in weather conditions that were below the 5km visibility required for such a maneuver. Contributing factors included the lack of ground-based navigation aids at Kokoda Airport, the crew's decision to continue the approach into obscured terrain, and potential distractions or workload increases due to the challenging environment.
Video Analysis
No video analysis linked for this case file yet.
Airframe & Maintenance
Crew Experience
Captain
Jannie Moala
First Officer
Rodney Souka; not IFR qualified.
Systems & Failure Modes
GPS Tracking Device
A small electronic telemetry device with non-volatile memory that allowed investigators to reconstruct the flight path in the absence of a flight data recorder.
Emergency Locator Transmitter (ELT)
A device that activated upon impact, allowing search and rescue aircraft to locate the wreckage the following day.
Interesting Facts
- 01The aircraft was not equipped with a Cockpit Voice Recorder or Flight Data Recorder as they were not required by regulations for this aircraft type.
- 02The Captain had 2,177 total flying hours, with 1,836 hours on the Twin Otter.
- 03The First Officer had 2,150 total flying hours, with 1,940 hours on the Twin Otter, but was not qualified for Instrument Flight Rules (IFR).
- 04Visibility in the Kokoda Gap at the time of the accident was less than the 5km required for a visual descent.
- 05The aircraft was built in 1975 and had accumulated 46,700 flying hours.
Safety Actions & Advisories
GPS Training Implementation
The operator introduced a specific GPS training package for non-precision approaches to improve crew proficiency with satellite navigation.
Threat and Error Management Training
The investigation recommended the adoption of Threat and Error Management (TEM) training for flight crews to better identify and mitigate operational risks during flight planning and execution.
Regulatory Surveillance Enhancement
The Civil Aviation Safety Authority of Papua New Guinea was advised to improve surveillance of operators to ensure compliance with flight rule regulations.