On 13 December 2013, an Airbus A330-200 (PK-GPN) being operated by Garuda Indonesia on a scheduled domestic passenger flight from Bali to Jakarta Soekarno-Hatta left the runway shortly after touchdown in heavy rain in daylight and continued parallel to the 60 metre-wide runway with the right main landing gear on the grass for 500 metres before regaining the runway. Resultant damage included a loss of hydraulic system integrity which meant that the aircraft was unable to taxi and it was towed to the parking gate. There were no injuries to the 198 occupants.
An Investigation was carried out by the Indonesian National Transportation Safety Committee (NTSC). The FDR and 2-hour CVR were successfully downloaded and a detailed analysis of the final part of the flight was therefore possible.
It was noted that the 63 year-old Captain had accumulated approximately one third of his 25,594 flying hours on the aircraft type involved and that the 24 year-old First Officer similarly had accumulated almost a third of his 2671 flying hours on the type.
It was established that after commencing an auto-ILS approach to Runway 25L at Jakarta, the Commander, as PF, had made an ATC-approved deviation to the right between 3000 feet and 2000 feet in order to avoid Cumulonimbus (Cb) (CB) cloud after which the aircraft was re-established normally on the ILS. Recorded data showed that at an altitude of 184 feet (equivalent to 150 feet aal), the wind direction had changed from westerly to southerly and the wind speed had then begun to increase from 4 knots to reach 24 knots by the time the aircraft touched down.
The AP was disengaged at 124 feet agl with the aircraft on the ILS LOC but soon afterwards, both pilots reported that the aircraft had suddenly entered heavy rain. This had mainly affected forward visibility through the left windshield and had resulted in the PF losing visual reference. FDR data showed that the aircraft had begun to drift to the right from 90 feet agl. The First Officer stated that "he was able to see the runway all the time and observed that the aircraft was slightly on the right of the runway". This awareness of the relative position of the runway surface had prompted him to make two "fly left" calls round about the time of the automated FWC callout of "TWENTY". Having completely lost forward visibility, the PF reported having felt that the aircraft had floated slightly and this was confirmed by FDR data. The aircraft touched down with the right main landing gear on the grass, travelled for 500 metres then regained the runway before entering an exit and stopping. Damage sustained to the right side hydraulics meant it was not possible to taxi safely so a tow-in to the parking gate was arranged.
Damage caused to the aircraft by the excursion was subsequently found to be limited to a hydraulic leak on the right landing gear actuator and cuts to one of the tyres on the right main landing gear. It was noted that the 3600 metre-long Runway 25L was 60 metres wide.
The decision of the Commander to continue to land rather than go around when visibility was suddenly lost and the absence of a go around call at that point from the First Officer, were considered. It was concluded that the situation encountered - the de-stabilisation of the approach with touchdown imminent - was within the requirements for a go around in both the Garuda 'Basic Operation Manual' (BOM) and the A330 FCOM. Inclusion of a recurrent training exercise based on similar conditions to the investigated event found that "most of the pilots could not achieve a normal landing on the runway".
It was considered that "at low altitude prior to touch....a decision to go around....has to be made by the pilot in a very short time" and is in effect an "intuitive decision". Such a decision must be made either on the basis of long term memory based on experience, procedural awareness and training or short term memory based on inclusion of the situation encountered in the approach briefing - which did not occur in this case. It was concluded that the PF decision to continue landing was most likely an indication of an absence of relevant long term memory.
The observing and reporting of visibility was reviewed. It was clear that the weather experienced during touchdown was not expected by the pilots and it was not expected in the context of the weather reports issued for the airport. The weather report issued for exactly the same time as the landing being investigated gave the surface wind as 270º / 10 knots with a visibility of 4000 metres in Moderate Rain with an unspecified cloud cover of CB base 2000 feet aal and 'No Significant Weather'. The next report was issued 45 minutes later. These reports were the responsibility of the Badan Meteorologi Klimatologi dan Geofisika (BMKG), the Indonesian Agency for Meteorology, Climatology and Geophysics which makes observations "every 30 minutes or if any significant change of weather occurs" which is then broadcast on the Automatic Terminal Information Service (ATIS).
The Conclusion of the Investigation was that "during the hand flying at approximately 90 feet agl, the aircraft bank angle was an average of 2° to the right for approximately 12 seconds which resulted in aircraft deviation to the right, after the PF lost visual reference and prolonged the flare prior to touchdown".
Contributing Factors were determined as:
- The loss of visual reference was an indication for go around which was not executed, this might have been the result of insufficient pilot intuitive decision making to cope with such a situation.
- The absence of any indication of significant weather in the weather report given to the crew might have influenced the pilot's judgment and reduced the expectation of any weather change which would require pilot decisions especially when at very low altitude.
Eight Safety Recommendations were made as a result of the Investigation as follows:
- that Garuda Indonesia should evaluate the flight crew ability when changing control the aircraft from automatic flight to hand flying especially when this occurs at the same time as one or more condition changes such as wind speeds and directions and visibility at a critical point in the flight.
- that Garuda Indonesia should reinforce pilot discipline in respect of the current operations manuals in respect to the procedure that contributed to this serious incident as discussed in the chapter 2 analysis section of this report.
- that Garuda Indonesia should enrich long term memory in relation to pilot intuitive decision making at critical flight condition.
- that the Badan Meteorologi Klimatologi dan Geofisika (BMKG) (the Metrological Climatology and Geophysical Agency) should comply with the Recommendation of the ICAO Annex 3 paragraph 3.4.6
- that the Badan Meteorologi Klimatologi dan Geofisika (BMKG) and AirNav Indonesia should review the internal network to improve the timely communication of information on the observed weather to pilots.
- that with reference to past and similar events to the one investigated here and recommendations made as a result, it is necessary for the BMKG and AirNav Indonesia to mandate the implementation of the ICAO Annex 3 paragraph 3.4.6 Recommendation.
- that the Director General of Civil Aviation should, noting past and similar occurrences on which Recommendations similar to those made here to the BMKG and AirNav Indonesia, actively facilitate the Recommendations now made to these agencies.
- that the Director General of Civil Aviation should oversee the correct interpretation and implementation of the Recommendations in this report, to ensure their effect on safety improvement for Operators.
The Final Report was released on 21 July 2014.