History of the Flight
On 12 December 2008, a de Havilland DHC6-400 Twin Otter aircraft, registered PK-BRS, operated by PT. Aviastar Mandiri, was conducting a series of scheduled flights from Timika, Papua. The final flight of the day was a return trip from Timika to Ewer, with each leg lasting about 36 minutes. The copilot was the handling pilot for the sector from Ewer to Timika, while the pilot in command (PIC) served as the support and monitoring pilot.
According to the PIC, the aircraft began sliding before the brakes were released. Shortly after commencing the take-off roll, the aircraft veered to the right. The PIC then took over control from the copilot but was unable to prevent the aircraft from swinging to the left. The aircraft crossed the centreline and rolled to the left side of the runway. The PIC aborted the takeoff and attempted to regain the runway centreline using nose-wheel steering. This attempt was unsuccessful, and the aircraft veered further left, sliding off the runway into wet soft ground at the edge of the marsden matting surface. The aircraft came to a stop 360 meters from the departure end of the runway, on a heading of 190 degrees.
The PIC shut down the engines and instructed the copilot to disembark the passengers. None of the occupants were injured.
Aircraft Information
The aircraft was a Twin Otter DHC6-400, registration PK-BRS. It was operated by PT. Aviastar Mandiri. The report noted that the aircraft had a marsden matting steel plate runway surface at Ewer Airstrip.
Meteorological Information
The source provides no specific meteorological information for the accident time, other than the ground being wet and soft.
Wreckage and Impact Information
After coming to rest, the forward fuselage and nose landing gear were buried in soft ground. The nose landing gear assembly and nose structure were damaged. The ADF antenna was broken, and rudder cable tension had slackened due to structural damage at impact. One left propeller blade was damaged. The aircraft sustained damage to the airframe.
Investigation Findings
The investigation was unable to determine why the pilots were unable to maintain directional control during the take-off roll. It is likely that when the PIC took control from the copilot and used nose-wheel steering, he may have overcorrected, resulting in a loss of directional control.
The NTSC made recommendations to the Directorate General of Civil Aviation (DGCA) to require operators to ensure that remote airstrips have effective means of communicating with regional authorities, and to address runway serviceability and traction on marsden matting airstrips in wet conditions.