What happened
On August 11, 2018, a PAC 750XL, registration PK-HVQ, was conducting an unscheduled passenger flight from Tanah Merah to Oksibil under the operation of PT. Marta Buana Abadi (Dimonim Air). At the time of the flight, meteorological conditions at the destination were below the required Visual Flight Rule (VFR) minimums and remained poor. Despite these conditions, the pilot proceeded with the flight after observing other aircraft successfully completing similar routes.
The aircraft departed Tanah Merah at 13:42 local time carrying one pilot, one observer, and seven passengers, with a total passenger and baggage weight of 473 kg. No mechanical issues were reported prior to takeoff. At 14:11 local time, the pilot contacted Oksibil Tower to report an altitude of 7,000 feet and an estimated arrival time of 14:20 local time. During this communication, the controller informed the crew that visibility was limited to between 1 and 2 km due to heavy cloud cover.
By 14:16 local time, the pilot reported being positioned over Oksibil Airport, and the tower instructed the aircraft to proceed toward runway 11. Following this, the crew ceased all radio communications. The wreckage was located the next day on a mountain ridge approximately 3.8 nautical miles northwest of Oksibil at an elevation of roughly 6,800 feet. The accident resulted in eight fatalities and one serious injury.
Findings
Investigations by the KNKT identified that the pilot failed to adhere to VFR weather minimum requirements, which prevented a clear view of the surroundings. The investigation concluded that the pilot lacked sufficient knowledge regarding the local terrain. Furthermore, because the Terrain Awareness and Warning System (TAWS) did not provide an audible alert while the aircraft approached the ground, the pilot maintained insufficient situational awareness while flying through clouds, leading to the impact with terrain.