What happened
On 13 April 2013, a Boeing 737-800, registration PK-LKS, operated by Lion Air, was performing a scheduled flight from Bandung to Bali. During the final approach to Ngurah Rai International Airport, the aircraft encountered heavy thunderstorms and rain clouds. As the aircraft descended below the minimum descent altitude (MDA), the flight path became unstable, with a descent rate exceeding 1,000 feet per minute. The crew attempted a go-around maneuver, but the decision and execution occurred at an altitude too low to successfully recover the aircraft. The plane subsequently impacted the ground, resulting in no fatalities among the 101 passengers and 7 crew members, though the aircraft sustained significant damage.
The investigation
The KNKT investigation examined flight data, cockpit voice recordings, and meteorological reports. Investigators analyzed the aircraft's vertical and lateral profiles, noting a transition from automatic to manual flight during the approach. The inquiry also reviewed the airport's rescue and firefighting (ARFF) response, finding that the actual response time was four minutes, exceeding the three-minute standard. Additionally, the investigation looked into the accuracy of weather reporting, as the ATIS visibility information provided to the crew did not match the actual obscured conditions on the runway.
Findings
- The flight crew lost situational awareness regarding visual references after entering a rain cloud below the MDA.
- The aircraft's descent rate became excessive and unstable during the final stages of the approach.
- The pilot in command initiated a go-around at an insufficient altitude to complete the maneuver safely.
- The crew was not provided with timely or accurate weather updates, as the reported visibility was significantly higher than the actual conditions.
- Crew Resource Management (CRM) practices were ineffective in identifying and managing the increasing flight risks.
Safety action
Following the accident, Lion Air implemented a new policy requiring an immediate go-around if any loss of control or reduced visual reference occurs, particularly below 1,000 feet. The KNKT also issued recommendations to the Indonesian Directorate General of Civil Aviation to oversee pilot competency in manual flight and monitoring skills. Furthermore, recommendations were made to the airport authorities and meteorological agencies to improve the accuracy of visibility reporting and ensure firefighting response capabilities meet ICAO standards.