Description

On 18 May 2013, an Airbus A340-300 (CC-CQF) being operated by LAN Airlines Chile on a scheduled international passenger flight from Auckland to Sydney commenced take off from Runway 23L at Auckland in good night visibility. The aircraft was aligned with the runway edge lights instead of the runway centreline lights and after approximately 1,400 meters it corrected onto the centreline and completed the take off without ATC awareness. ATC were not subsequently advised and damage to seven edge lights was not discovered until the next routine inspection nearly three hours later. After an uneventful flight, tyre damage to the aircraft was found and tyres replaced. There was no other damage and none of the 206 occupants were injured.

Investigation

The event was investigated by the New Zealand Transport Accident Investigation Commission (TAIC). Recorded airport video was used to identify which aircraft had damaged the edge lights. By the time the aircraft returned to Auckland, relevant CVR data had been overwritten because it had not been stopped. Relevant QAR data was supplied by the aircraft operator and ATC MLAT data and radio transmission recordings were also available.

The 64 year-old Captain had 32,336 hours total flying experience which included 10,575 hours on the A340. The 36 year old First Officer had 3263 hours total flying experience which included 756 on the A340. It was considered that the prevailing weather and movement surface conditions at Auckland had been benign and were not a factor in the sequence of events.

It was established that with the Captain as PF, the aircraft had been taxied toward the 45 metre wide runway 23L for an early morning departure. As it approached the runway at the full length 'A1' position, the TWR controller had, after confirming that the crew were ready for take-off, issued a clearance to line up. Shortly afterwards, as the aircraft was crossing the flush-mounted runway edge lights, a take-off clearance was given and the Captain turned on the aircraft landing lights and switched the taxi/take-off lights to the brighter 'take off' position. The Captain subsequently stated that after doing this, he could not recall seeing the lights marking the lead-in line to the runway centreline but he did recall seeing a line of bright lights and "thinking that they marked the runway centreline". He then completed a sharp turn to the right to line up with those lights and continued with a rolling take-off. The First Officer reported that he was 'head down' for most of this time and briefly "glanced up and saw a single line of lights straight ahead then returned to monitor the engine instruments and the airspeed during the take-off". After accelerating along the edge lights, the Captain reported that he had realised the error and had "corrected the aeroplane to the runway centreline and completed the take off". It was found that approximately 1400 metres of the take-off roll had been made aligned with the right edge lights. The First Officer subsequently stated that he "did not notice the runway misalignment but he did feel a small heading correction as the aeroplane accelerated on the runway".

During the climb out, the Captain commented to the First Officer that "he thought he may have been lined up on the runway edge lights" but the First Officer said that he had not noticed anything unusual. ATC were not advised that they had initially been aligned with the edge lights and the TWR controller did not notice anything unusual as it was still dark.

Damage to the one of the NLG tyres was noticed by the ground engineer who met the aircraft in Auckland and advised the Captain. They then made an inspection of the other lading gear assemblies and damage was also found to one of the centre landing gear tyres. Both these tyres were then replaced.

It was found that recorded track along the right runway edge matched the tyre tracks created by the aircraft and that it "was so accurately aligned with the runway edge lights that many of the elevated lights had passed between the double wheels of the nose undercarriage and the centre main undercarriage without being damaged". Since the MLG legs were 5 metres either side of the aircraft fore-aft centreline, all MLG wheels "remained on either the runway or the strengthened shoulder". However, the outboard right-hand engine was over the grass during the excursion and came within 4 metres of a row of movement area guidance signs.

It was confirmed that "the taxiway and runway physical dimensions, markings and lighting installations on the aerodrome met the CAA design standards for an international airport that supported operations in conditions of very low visibility". It was noted that "the runway centreline was marked with flush-mounted white lights" and that they were differentiated from the elevated edge lights by their spacing and intensity with the centreline lights 15 metres apart and the edge lights 60 meters apart. These centreline lights have "narrowly focussed beams aligned with the centre of the runway”. The elevated runway edge lights have "narrow, high-intensity beams angled in towards the runway centre at three degrees from the edge line and omnidirectional beams". It was noted that the effect of these characteristics was that when an aircraft is on the centreline, "runway edge and centreline lights appear as three white lines converging in the far distance, with the edge lights brighter than the centreline lights".

TWR Controllers were able to vary the intensity of the runway and taxiway lighting through a range of preset steps and although they were recommended to use particular intensities for specific conditions, they were allowed some discretion and could adjust settings if a pilot so requested.

In an attempt to understand how the Captain's attention was diverted from continuing to follow the green lead in lights as the aircraft entered the runway, it was noted that his view would have been interrupted when he looked outside to check that the approach was clear and then up to the overhead panel to select the landing lights on and the taxi lights to the higher take off position. The tight turn to the right onto the edge lights had occurred when his view outside was redirected towards the runway after looking away and it was considered that this "suggests that his mistake occurred after he had lost his previous lead-in cues". It was considered that at this point, "the brighter landing lights reflecting off the concrete runway may have diminished the visibility of the taxiway centreline lights, although the paint marking would have become more visible". Since the operator's Standard Operating Procedures (SOPs) allowed the PF to choose whether to select the landing lights on themselves or ask the other pilot to do this, it was considered that best practice would have been to request the First Officer to operate the light switches. The rolling take-off was considered to have reduced the opportunity for either pilot to recognise the mistake made.

In reviewing the relative lighting intensity, the guidance provided in the ICAO Aerodrome Design Manual (Doc 9157) for the prevailing conditions was compared with that of the settings that had been in use for the investigated take-of which were normal practice for those conditions. The Table below shows that whilst the intensities were not as recommended and the runway lights were both much brighter than recommended, the edge lights were, as recommended, brighter than the centreline lights.

The Investigation noted that "adherence to the ICAO standards provides pilots anywhere in the world with consistent cues for ground manoeuvring, so any variance from the standards can contribute to a pilot making an error". It concluded that the variances in lighting seen at Auckland Airport are a safety issue which needs to be addressed.

Some "errors and differences" in the CAA Advisory Circular which provides guidance on aerodrome design and operational requirements in New Zealand relative to the corresponding ICAO SARPs were also identified during the Investigation and although it was concluded that they had no bearing on the investigated event, it was considered that since no differences were filed with ICAO, rectification was required.

The fact that a number of similar events involving misaligned take-offs at night had been the subject of Serious Incident Investigations was noted, as was the existence of an ATSB Study 'Factors influencing misaligned take-off occurrences at night' published in 2010. Some previous events were directly referred to including a 2012 Airbus A330 event at Abu Dhabi, a 2011 Bombardier CRJ event at Dubai, a 2006 Airbus A319 event at Las Vegas and a 2002 ATR72 event at Dresden.

In respect of Cause and Contributory Factors, the formally stated Finding of the Investigation was that "while the pilots were conducting last-minute checks and tasks before the take-off, the Captain lost awareness of precisely where his aeroplane was in relation to the runway centreline".

Three Contributory Factors relating to the commencement of the take-off whilst misaligned were also given:

• the potential illusion created by the illuminated manoeuvre area guidance signs parallel to and along the length of the runway, which, in the absence of a thorough check of aeroplane position, could be mistaken for the runway edge lights
• no other means were used to confirm positively the aircraft position such as the First Officer's cross-check or reference to the use of on-board navigation systems
• the rolling take-off reduced the time available for either pilot to realise the error.

It was concluded that whilst "the intensities of the taxiway centreline lights and the runway lights at the time of the incident did not meet those recommended by the International Civil Aviation Organisation", it was not possible to determine whether this safety issue contributed to this particular incident. Nevertheless it is an issue that should be addressed to enhance aviation safety. It was also accepted that, whilst the content of regulatory guidance material relating to aerodrome design requirements was presented in such a way that it "may have led to the inconsistent application", the "errors and differences" found "did not contribute to this incident". However, the Investigation was "concerned that such "errors and differences" could contribute to accidents in the future".

Safety Action taken as a consequence of the event and the investigation into it was noted to have included the following:

• LAN Airlines revised the before-take-off checks in its FCOM to ensure that it was stated that the aircraft instrumentation could show runway alignment that was to be used routinely and not only during low-visibility conditions.
• Whilst the Investigation was in progress, the CAA, which "had been in the process of reviewing Part 139 for several years" issued an amendment to it which included the addition of an appendix dedicated to visual aids. The CAA stated that it intends to "co-ordinate and update the electronic filing of differences from ICAO Annex 14, Volume 1" when further revision of Part 139 and its associated advisory circulars is completed in 2016.
• A wide entrance to a runway has been recognised as a contributing factor in some runway take-off misalignments (although not this one). Nevertheless, ANSP Airways has, in conjunction with Auckland International Airport, realigned the taxiway edge marking at the intersection of taxiway A1 and runway 23L and added transverse stripes on the inside corner. The intention of these measures is to reduce the apparent width of the taxiway at the intersection.

Three Safety Recommendations were made during the course of the Investigation as follows, the first two on 1 February 2016 and the third on 22 February 2016:

• That the Director of Civil Aviation review the use of 'should' in advisory circulars so that any ambiguity regarding compliance requirements is removed. [017/15]
• That the Chief Executive of Auckland International Airport Limited, in conjunction with the Chief Executive of Airways (the ANSP), measure and recalibrate luminous intensity settings for the taxiway centreline lights, runway centreline and runway edge lights and reconfigure the associated control tower setting selections so that controllers may select the respective light intensities recommended by ICAO for various levels of ambient lighting. [019/15]
• That the Director of Civil Aviation, in conjunction with the Chief Executive of Airways, check that aerodrome runway lighting systems at all certificated aerodromes comply with Part 139. [020/15]

The Final Report of the Investigation was approved for publication in December 2015 and subsequently made available with the addition of the three subsequently-issued Safety Recommendations and the responses of their addressees.

Related Articles

• Runway Excursion
• Runway Identification
• Runway Lighting
• Situational Awareness
• Information Processing
• Interruption or Distraction

Further Reading

• Factors influencing misaligned take-off occurrences at night, ATSB Australia, 2010.