What happened
On 11 May 2023, a Cessna 208B, registered PK-NGA, was conducting a commercial cargo and passenger flight in the Papua region of Indonesia. The aircraft, operated by PT Nasional Global Aviasi, was traveling from Dekai to Fenteheik when the crew encountered difficulties during the final approach to Runway 17.
As the aircraft approached the airstrip, the crew noted that the plane was significantly higher than the required altitude. Company route guidance mandated passing a specific "Key Point" at 6,100 feet; however, the aircraft passed this point at 6,400 feet. The pilot in command elected not to abort the approach, citing the high terrain surrounding the airstrip as a barrier to a go-around maneuver.
During the descent, the rate of sink increased significantly. By the time the aircraft was approximately 300 feet above the airstrip elevation, the rate of descent had reached 1,600 feet per minute. Upon touchdown, the aircraft bounced twice. During the third impact, the nose gear collapsed, causing substantial damage to the aircraft. The two crew members evacuated the wreckage without injury.
The investigation
The KNKT investigation focused on the flight path, the aircraft's configuration, and the adherence to stabilized approach criteria. Investigators reviewed GPS flight data, which confirmed the aircraft was above the prescribed altitude at the Key Point. The investigation also examined the operator's manual, which defines an unstabilized approach as having a sink rate exceeding 1,000 feet per minute without a prior special briefing. Furthermore, the investigation looked into the terrain constraints and the company's established route guidance for the Fenteheik airstrip.
Findings
- The aircraft was operating within its approved weight and balance limits.
- The crew was aware that the aircraft was above the altitude specified in the company's route guidance.
- The pilot in command decided against an aborted approach due to the high terrain surrounding the airstrip.
- The aircraft's rate of descent exceeded the 1,000 feet per minute threshold defined in the operator's stabilized approach procedure.
- The landing was characterized by multiple bounces, leading to the structural failure of the nose gear.
Safety action
Following the incident, the operator updated its route guidance for Fenteheik to clarify abort maneuvers, specifically instructing pilots to perform any landing cancellation before reaching the Key Point. The company also issued a notice to all pilots emphasizing the strict implementation of stabilized approach procedures and the necessity of adhering to altitude restrictions.