Flight and Incident
Following an uneventful flight from Jakarta, the crew commenced descent to Makassar (Ujung Pandang) Airport. On approach to runway 31, the flaps were selected down from 15° to 30° when the captain observed an asymmetrical condition between both flaps. The captain decided to set the flaps back to 15° and continue the approach in that condition.
Landing and Runway Excursion
The aircraft landed hard to the left of the runway centerline and bounced twice. Out of control, it veered off the runway, lost its right main landing gear, and came to rest several dozen meters further. The left main gear punctured the fuel tank, and the fuselage was deformed.
Evacuation and Damage
All 164 occupants evacuated safely. The aircraft was damaged beyond repair.
Investigation Findings
The exact cause of the asymmetrical flaps condition on approach is undetermined. The official findings state that since all the conditions were clearly not met, the pilots should have made the decision to initiate a go-around procedure.