A320, Brunei, 2014
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Revision as of 22:37, 15 January 2018 by Content.Manager
|On 7 July 2014, an Airbus A320 landing at Brunei departed the side of the runway almost immediately after touchdown and continued to gradually diverge from the runway axis until stopping after a ground run of approximately 1,050 metres. The Investigation concluded that the aircraft commander, having taken over control from the First Officer when the latter lost their previously-acquired prescribed visual reference below Decision Altitude due to a sudden-onset intense rain shower ahead, had then continued the approach without recognising that the only lights still visible to him were those at the right hand edge of the runway.|
|Actual or Potential
|Human Factors, Runway Excursion, Weather|
|Flight Conditions||Not Recorded|
|Type of Flight||Public Transport (Passenger)|
|Origin||Kuala Lumpur International Airport|
|Intended Destination||Brunei International Airport|
|Take off Commenced||Yes|
|Location - Airport|
|Airport||Brunei International Airport|
|Tag(s)||Unplanned PF Change less than 1000ft agl|
Plan Continuation Bias
|Tag(s)||Off side of Runway|
|Damage or injury||Yes|
|Causal Factor Group(s)|
On 7 July 2014, an Airbus A320 (9M-AQA) being operated by Air Asia Berhad on a scheduled international passenger flight from Kuala Lumpur to Brunei (Bandar Seri Begawan) as AK278 touched down at destination on the right hand edge of runway 03 and then ran onto the grass alongside it and continued to slowly deviate from the runway axis until coming to a stop 1,300 metres from the landing threshold. An emergency evacuation was ordered and accomplished during which 1 of the 109 occupants was slightly injured. The excursion caused damage to the aircraft landing gear and both engines and also to aerodrome lighting, signage and electrical supply infrastructure.
An Investigation was carried out by the Brunei Air Accident Investigation Team (AAIT) with assistance provided by the AAIB Singapore in accordance with an MoU on Air Accident Investigation. Data from the accident aircraft FDR and CVR were successfully downloaded and used to support the Investigation.
The 29 year-old Captain, who had been promoted to command just over 5 months prior to the accident, had accumulated 6,100 hours total flying experience of which 2,554 hours were on type. His command experience totalled 340 hours. The 23 year-old First Officer had 970 hours total flying experience of which 640 hours were on type.
It was established that the sector had been conducted with the First Officer as PF and that the ATIS wind velocity for the approach had been 280°/11 knots and the visibility 8,000 metres. On checking in with Brunei Radar, the crew were advised that the surface wind was unchanged but visibility was now 5000 metres. On asking if there were any showers in the vicinity, the controller responded that there were not. Thirteen minutes later, with the aircraft established on final approach to runway 03, the TWR controller issued a landing clearance accompanied by a spot wind of 270°/11 knots, updating the wind 1½ minutes later (2½ minutes prior to the subsequent touchdown time) to 210°/7-10 knots (i.e. equivalent to a tail wind component of 7-10 knots). About this time, the Captain reported that he had observed that it had begun to rain in the vicinity of the runway and upon his request, the TWR controller advised that "there was rain only at the threshold of runway 03".
A stabilised final approach was flown and at a recorded 965 feet agl, the Captain briefed his First Officer to perform a go around "if visual reference with the runway cannot be established". The runway approach lighting system was called in sight at a recorded 637 feet agl and the PAPI as in sight at 581 feet agl. At a recorded 313 feet agl, the First Officer announced that he would land and disconnected the AP. 'Minimums' was auto-annunciated (the Captain had set the DH to 309 feet) and almost immediately, heavy rain was encountered and the Captain selected the windshield wipers on at the 'fast' position. The TWR controller stated that at about the same time, he had "received a weather update from the meteorological station where the visibility was 3000 metres between south-east and south" but had not passed this information to the aircraft as it was very close to touch down and "he did not want to interrupt the flight crew’s operation".
At a recorded 157 feet agl, the First Officer called for the Captain to take control which he immediately did, acknowledging verbally, “Okay I have control”. Almost immediately after this handover, the First Officer was recorded as saying “I can’t see anything” to which the Captain verbally acknowledged with “Check” after which there were no further exchanges prior to touchdown. According to the Captain, he had seen a single row of white runway lights ahead which he had "believed were the runway centreline lights" and had therefore continued the approach and steered the aircraft towards them. FDR data confirmed this slight change of track to the right.
Twenty one seconds after DA, both main landing gears "touched down on the runway pavement, close to the right edge of the runway" and in the TDZ followed, about three seconds later, by the sound of "ambient noises corresponding to the aircraft veering off the runway" on the CVR. The Captain attempted to regain the runway by applying left rudder but this had no effect and the aircraft continued on the grass in a straight line gradually increasing its deviation from the runway axis. It subsequently "travelled across taxiway E4 onto another grass patch before coming to a stop" after a ground run of 1,046 metres. The Captain ordered an emergency evacuation which was accomplished using the four doors but not also the over-wing exits. One minor injury was sustained by a passenger.
The Investigation further established the following:
- the runway lighting had been functioning normally prior to damage caused by aircraft impact.
- Operator Standard Operating Procedures (SOPs) permitted the First Officer to land the aircraft as long as the reported surface wind was not more than 15 knots with no restriction on tail wind component.
- Pilot simulator training at the Operator included mandatory practice of a go around from 30 feet agl with one engine inoperative and for new Captains this also included "low and high flare scenarios requiring go-arounds to be performed from 50 feet agl". This training did not include such practice in low visibility conditions for which mandatory go around practice required commencement "before minima".
- That having lost visual reference, the First Officer reported at the subsequent interview that commencing a go around "did not cross his mind" and that instead, he had "believed that the Captain, being more experienced, would be able to land the aircraft".
It was noted that a handover of control after DA introduces two "likely safety risks":
- The pilot receiving control of the aircraft may have insufficient time to react appropriately and establish positive control.
- Should the pilot receiving control of the aircraft decide to perform a go-around, valuable time and altitude lost during the handover would have increased the challenge to execute a safe go-around.
In this context, it was noted that since the handover of control had occurred 13 seconds prior to touchdown, the Captain "would have had enough time to maintain control of the aircraft" and had "acknowledged the handover without hesitation" but had been "unable to establish proper situational awareness to ensure that the row of lights he saw was the runway centreline lights". With this in mind, it was considered that the Captain's actions indicated that on taking control, he had been subject to the coning of his attention, a process defined as occurring when "instead of gathering a broad spectrum of data to make a good decision, one concentrates on a single source of information".
It was considered that the investigated event "highlights the need for a go-around to be performed when the approach is destabilised below minima" despite the fact that such a decision "may be difficult to take" whilst "remaining the proper one in such circumstances".
The Investigation did not formally record a Cause or Contributory Factors for the event but instead documented its Conclusions which included the following description of the final stages of the flight:
- Two seconds after passing DA, the flight crew encountered intense rain to the extent that the PIC had to switch the wiper on to the “Fast Setting”.
- Five seconds later, at 157 Feet AGL, the FO lost visual reference with the runway and decided to hand over control of the aircraft to the PIC instead of performing a go-around.
- When the PIC took over controls of the aircraft, he saw only a row of white runway edge lights, which he believed to be the runway centreline lights. He provided inputs through the control stick and piloted the aircraft towards that row of lights which was the right runway edge lights.
- The aircraft touched down on the runway pavement, close to the right edge of the runway. Shortly after, the aircraft veered onto the grass patch to the right of the runway edge.
- Unable to bring the aircraft back to the runway, the PIC brought the aircraft to a stop on the grass patch and ordered an emergency evacuation.
Safety Action taken by Air Asia Berhad during the course of the Investigation were noted as having included the issue of a "reminder" to all its pilots which covered the following:
- Proper handing and taking over control of aircraft
- Rejected landing procedures
- Operator’s criteria of the required visual reference to the intended landing runway
- Associated risk of cross wind conditions during landing and the recovery techniques
One Safety Recommendation was made as a result of the Investigation as follows:
- that Air Asia Berhad should consider introducing simulator training for go-around below minima in response to weather conditions that result in the rapid reduction or loss of visual reference to the runway.
The Final Report was completed on 21 May 2015 and subsequently published in English.