What happened
On 9 September 2014, a Cessna C208B Grand Caravan, registration PK-RSC, was performing an unscheduled flight from Sentani Airport to Mulia Airport in Papua, Indonesia. The flight, operated by PT Enggang Air Service, was conducted under Visual Flight Rules (VFR) with two crew members and nine passengers on board.
As the aircraft approached runway 08 at Mulia Airport—a high-elevation site situated at 5,500 feet with a 10% uphill slope—the pilot completed the landing procedures at approximately 500 feet above ground level. Upon touchdown, the aircraft bounced and floated along the runway. Following a second contact with the surface, the aircraft began to drift toward the left side of the runway. In an attempt to correct the deviation, the pilot applied full right rudder, brakes, and reverse thrust. However, these actions failed to stabilize the aircraft, which continued to veer left until the left main and nose landing gears struck soft soil, causing the aircraft to stop off the runway.
The investigation
The investigation by the KNKT focused on the aircraft's alignment during approach and the specific landing techniques used during the rollout. Investigators examined the aircraft's airworthiness and the crew's adherence to the Company Operating Manual (COM).
Analysis of the flight path revealed that the aircraft was not properly aligned with the runway centerline during the final approach. The investigation also scrutinized the physics of the recovery attempt, noting that the application of reverse thrust and braking during the leftward drift created a backward moment that actually intensified the lateral movement toward the left edge of the runway.
Findings
- The pilot experienced a runway condition illusion caused by the 10% uphill slope, which led to a late flare and a subsequent bounce.
- The pilot's recovery actions, specifically the use of reverse thrust and braking while the aircraft was already veering, generated forces that pushed the aircraft further from the centerline.
- A lack of effective standard call-outs during the approach may have contributed to a lack of situational awareness regarding the aircraft's misalignment.
- The aircraft sustained damage to the propeller blades, the left main landing gear, and the aircraft belly.
Safety action
Following the incident, PT Enggang Air Service initiated several improvement plans, including reviewing route manuals and implementing a requirement for captains to complete 300 hours of flying in mountainous terrain. The KNKT recommended that the operator review cornering landing techniques and ensure pilots strictly adhere to standard call-out procedures. The Directorate General of Civil Aviation (DGCA) was also advised to oversee the implementation of these safety measures.