What happened
On 7 May 2011, a scheduled passenger flight operated by PT. Merpati Nusantara Airlines, flying from Sorong to Kaimana, crashed into the sea near Utarom Airport. The aircraft, a Xi’An MA60 with registration PK-MZK, was operating under Instrument Flight Rules (IFR), though the destination airport lacked a published instrument approach procedure, requiring a transition to Visual Flight Rules (VFR) for the final approach.
During the final segment of the flight, the crew was attempting to locate the runway visually. At this time, the weather at Kaimana was characterized by rain and low visibility, with ground visibility reported at approximately 2 kilometers—significantly below the 5-kilometer minimum required for VFR operations. As the crew focused on looking outside the cockpit to sight the runway, the aircraft's flight path became unstable, with the bank angle increasing to 38 degrees. The aircraft then entered a rapid descent, reaching a rate of approximately 3,000 feet per minute before impacting the water about 800 meters southwest of the runway threshold. All 25 occupants—including 2 pilots, 2 flight attendants, 2 engineers, and 19 passengers—were fatally injured.
The investigation
The investigation examined the flight's final minutes using data from the Flight Data Recorder (FDR) and Cockpit Voice Recorder (CVR). Investigators analyzed the aircraft's descent profile, the meteorological conditions at the time of arrival, and the crew's performance during the approach. The inquiry also reviewed the crew's training, cockpit discipline, and the operational environment, specifically focusing on how the pilots managed the transition from instrument to visual flight under degraded visibility conditions.
Findings
- The primary cause of the accident was the crew's failure to monitor the aircraft's instruments during the final approach segment.
- Both crew members were distracted by looking outside the cockpit in an attempt to visually acquire the runway.
- The flight was conducted in weather conditions that did not meet the minimum visibility requirements for VFR operations.
- A lack of effective monitoring allowed the aircraft to enter an uncontrolled descent and high bank angle without timely intervention.
- The investigation noted potential issues regarding cockpit discipline and the impact of external distractions on flight path maintenance.