What happened
On 6 August 2013, a Boeing 737-800, registration PK-LKH, operated by Lion Air, was performing a scheduled passenger flight from Makassar to Gorontalo. The aircraft was carrying 110 passengers and a crew of seven.
Upon landing on runway 27 at Djalaluddin Airport, the flight crew observed animals crossing the runway ahead. At approximately 120 knots and 550 meters from the start of the runway, the aircraft struck the animals. Following the impact, the pilots experienced ineffective braking response. The aircraft subsequently veered to the left and exited the runway, coming to a stop on the left shoulder approximately 2,100 meters from the runway threshold.
During the landing roll, the smell of burning meat entered the cabin. While the crew instructed passengers to remain seated, some passengers attempted to evacuate via an over-wing emergency window without instruction, resulting in two injuries (sprained ankles). Post-incident inspection revealed two dead cows lodged in the main landing gear, and the aircraft sustained damage to the brake system hydraulic lines and the weight-on-wheel sensor.
The investigation
The investigation focused on the breakdown of wildlife hazard management and the physical state of the airport perimeter. Investigators examined flight data recorder (FDR) information, which showed that while spoilers and reversers were deployed, the longitudinal deceleration was inconsistent with expected auto-brake settings due to the impact.
Data from the airport perimeter revealed that sections of the north and south fences were either broken or entirely missing, allowing livestock from the surrounding area to access the runway. Furthermore, the investigation found that a previous audit conducted in July 2013 had already identified these perimeter breaches, yet no corrective actions had been implemented by the airport authority to mitigate the high wildlife hazard.
Findings
- The primary cause of the excursion was the impact with livestock on the runway.
- Significant gaps and broken sections existed in the airport's perimeter fencing, particularly along the north and south sides of the runway.
- The airport's wildlife hazard management program, as required by its Aerodrome Manual, was not being effectively implemented.
- A prior audit had identified the broken fences, but the airport authority failed to execute a corrective action program.
- The aircraft's deceleration was significantly affected by the impact and the subsequent damage to the braking system's hydraulic lines.
Safety action
Following the incident, the Djalaluddin Airport Authority initiated temporary repairs to the perimeter fences and planned for full installation of new fencing. The authority also increased security oversight frequency. The NTSC issued recommendations to the Directorate General of Civil Aviation to ensure stricter oversight of aerodrome certification and to verify that wildlife hazard management protocols are strictly followed by all certificate holders.