What happened
On 26 September 2022, an ATR 72-212A, registration PK-PAH, was operating an unscheduled passenger flight from Bontang to Balikpapan. The flight, operated by PT Pelita Air Service, carried 42 people, including two pilots, two flight attendants, and 38 passengers.
During the approach to Runway 25, the aircraft encountered heavy rain. While the pilots had initially been informed of rain at their destination, the weather conditions deteriorated significantly during the arrival phase. As the aircraft approached the runway, visibility dropped to approximately 300 meters. Upon touchdown, the aircraft veered to the right, causing the right main wheel to exit the runway pavement. In the process of attempting to return to the runway, the left main wheel struck a runway edge light. The aircraft was able to taxi to a parking stand, where passengers were safely disembarked.
The investigation
The investigation by the KNKT focused on the sequence of events leading to the excursion and the communication of meteorological data. Investigators examined the flight records, including the flight data recorder and cockpit voice recorder, though the CVR data had been overwritten by a subsequent flight.
The inquiry also looked into the reporting procedures of the various stakeholders. It was noted that the aircraft operator, the airport operator, and the air traffic services provider did not proactively report the serious incident to the KNKT; the authorities only became aware of the event four days later when the KNKT confirmed the occurrence. Furthermore, while the tower controller recorded the event in the operational logbook, there was no evidence that management personnel had reviewed the log to identify the excursion.
Findings
- The primary cause of the excursion was the wet runway condition and significantly reduced visibility during the landing phase.
- The tower controller informed the crew that the runway was wet and that wind speeds had increased to 12 knots.
- There were inconsistencies in the procedures used by the air traffic services provider regarding the timing of visibility updates. While local procedures suggested providing weather information upon request, other standards required immediate notification of significant changes.
- A lack of timely reporting by the involved organizations delayed the official notification of the incident to the national safety committee.