What happened
On 22 July 2011, a Garuda Indonesia Boeing 737-300, registration PK-GGO, was performing a scheduled passenger flight from Jakarta to Malang. The flight crew, which included a Pilot in Command (PIC), a First Officer under line training, and a Second in Command, was executing a VOR/DME approach for Runway 35, followed by a circling maneuver to land on Runway 17 due to local wind conditions.
During the base leg for Runway 17, the aircraft turned too early, resulting in the aircraft being positioned to the right of the runway centerline and above the intended glide path. The PIC decided to take manual control from the trainee pilot to correct the flight path. In an attempt to stabilize the descent, the pilot increased the rate of descent and reduced power while simultaneously rolling the aircraft to realign with the centerline.
Upon touchdown, the aircraft experienced a significant vertical impact, recorded at 3.473 G, and subsequently bounced. The aircraft veered to the right of the runway centerline. Following the landing, air traffic controllers instructed the crew to stop the aircraft to assess the possibility of a hard landing, which the pilot confirmed.
The investigation
The KNKT examined flight data from the Flight Data Recorder (FDR) and cockpit audio from the Cockpit Voice Recorder (CVR). The investigation focused on the aircraft's stability during the final stages of the approach and the crew's decision-making process.
Data analysis revealed that the approach was unstable below 300 feet AGL. The FDR showed significant deviations in heading (changing from 140° to 174°) and roll angles (varying between 9° and 21°). Additionally, the sink rate reached up to 1,080 feet per minute, exceeding the 1,000 feet per minute limit required for a stabilized approach. The investigation also found that the aircraft's airspeed had dropped to 118 knots, which was below the required Vref of 130 knots.
Findings
- The approach was unstabilized from below 500 feet AGL in visual conditions.
- The PIC's decision to take control and continue the landing instead of performing a go-around was inconsistent with the operator's Standard Operating Procedures (SOP).
- There was a failure in Crew Resource Management (CRM), as the other crew members did not call out the unstable conditions or suggest a go-around.
- The aircraft was mechanically sound, with no system malfunctions or weight and balance issues identified.
- The hard landing resulted in damage to the nose wheel hub.
Safety action
Following the incident, PT. Garuda Indonesia issued engineering instructions for inspections and corrective maintenance on the aircraft, including borescope inspections of the engines and non-destructive testing (NDT) of critical components. The KNKT recommended that the airline re-emphasize the strict implementation of stabilized approach procedures and CRM philosophy to ensure all crew members actively participate in maintaining flight safety.