What happened
On 1 September 2025, an Airbus Helicopters MBB BK117 D3, registered PK-RGH, departed from Kotabaru for an unscheduled passenger flight to Palangka Raya. The flight, operated by PT. Eastindo Services, carried one pilot, one engineer, and six passengers. Before takeoff, the crew addressed a cockpit warning regarding an engine fire bottle indicator; after cleaning an electrical connector, the warning cleared and the flight proceeded under Visual Flight Rules (VFR).
During the flight, the pilot maintained contact with the Sjamsir Alam Flight Information Service, providing updates on their progress. However, after reporting an inability to establish communication with Banjarmasin Approach Control, the aircraft ceased all transmissions. The last recorded ADS-B data at 0903 LT placed the helicopter at 2,725 feet. Following a search operation, the wreckage was discovered on 3 September 2025 on a ridgeline. The impact caused a post-crash fire that destroyed the main fuselage, and the tail section was found separated further uphill. All eight occupants sustained fatal injuries.
The investigation
The KNKT investigation examined the aircraft's technical state, the flight's navigation aids, and the operational procedures in place. The investigation confirmed the aircraft was airworthy and within weight limits at dispatch. The crew utilized modern avionics, including a digital map and terrain awareness systems, supplemented by an iPad with the Garmin Pilot application.
Investigators also reviewed the communication logs between the pilot and the Sjamsary Alam Flight Information Service. They noted that while the aircraft was equipped with a Cockpit Voice and Flight Data Recorder (CVFDR), the unit was recovered in a severely damaged state. The investigation also looked into the meteorological conditions, noting mid-to-high level clouds were present in the area at the time of the accident.
Findings
- The operator lacked a published route guide for the flight path between Kotabaru and Palangka Raya, and this was the company's first operation on this specific route.
- The absence of specific area and route information, including minimum safe altitudes, left the crew with insufficient knowledge of the operational environment.
- There was a breakdown in air traffic coordination, as the Sjamsir Alam Flight Information Service did not notify Balikpapan Info of the flight, nor did they instruct the pilot to establish contact with that unit as required by standard operating procedures.
Safety action
Following the accident, PT. Eastindo Services issued safety notices to its personnel regarding critical procedures for operating in mountainous terrain. The KNKT has issued recommendations to the operator to ensure all flight crews are provided with comprehensive route and aerodrome information, and to AirNav Indonesia to ensure strict adherence to communication and notification protocols between flight information services.