What happened
On April 9, 2009, a British Aerospace BAe 146-300, registration PK-BRD, was operating a scheduled cargo and passenger flight from Sentani to Wamena, Papua. During the initial approach to runway 15 at Wamena Airport, the flight crew performed a go-around. While attempting a second approach via a right downwind leg, the aircraft struck terrain and was destroyed by the impact and a subsequent post-crash fire. There were no survivors among the crew, flight attendants, engineer, and loadmaster on board.
The investigation
The investigation focused on the aircraft's flight path and the performance of its Enhanced Ground Pro-ximity Warning System (EGPWS). While the EGPWS manufacturer confirmed that the system issued appropriate warnings in its standard mode, the enhanced "Look-Ahead" function appeared to have been inhibited following the initial go-around.
Investigators examined the cockpit voice recorder (CVR) and flight data recorder (FDR), noting that the crew did not respond to a significant series of alerts. Specifically, the crew failed to react to eight "DON'T SINK" and one "TOO LOW TERRAIN" alert during the downwind leg, as well as several "BANK ANGLE" and "TERRAIN" warnings during the base leg turn. The investigation also looked into the operator's training programs and the regulatory oversight regarding the aircraft's specific passenger-cargo configuration.
Findings
- The flight crew lacked situational awareness regarding the aircraft's proximity to the ground until the moment of impact.
- The crew failed to take remedial action in response to repeated, automated EGPWS aural warnings.
- The flight was not conducted in accordance with the operator's established operating procedures.
- The operator's training curriculum lacked detailed instruction on the specific EGPWS features installed on the aircraft.
- The simulator training program did not adequately prepare pilots for responses to EGPWS alerts.
- There was no clear procedure within the company manuals regarding when the terrain features of the EGPWS should be inhibited.