B763, Singapore, 2015
B763, Singapore, 2015
On 12 July 2015, a Japanese-operated Boeing 767-300 deviated from its acknowledged clearance and lit-centreline taxi routing and began take-off from a parallel taxiway in good night visibility, crossing a lit red stop bar in the process. When ATC observed this, the aircraft was instructed to stop which was achieved without further event. A subsequent take-off was uneventful. The crew did not report the event to their airline or their State authorities because the Captain determined that this case did not need to be reported and these organisations only became aware when subsequently contacted by the Investigating Agency.
On 12 July 2015, a Boeing 767-300ER (JA-606J) being operated by Japan Airlines on a scheduled passenger flight from Singapore Changi to Tokyo Haneda failed to follow its taxi clearance at night in normal ground visibility and attempted to take-off from a taxiway parallel to the departure runway. When ATC observed this, the controller instructed the aircraft to stop which was achieved without further event. After verifying with the flight crew that they could continue with the flight, it was re-cleared to taxi to the departure runway 20C via a new lit-centreline routing and the aircraft subsequently took off without further event.
A Serious Incident Investigation was carried out by the Accident Investigation Bureau (AAIB) of the Singapore Ministry of Transport. By the time the Investigation began, CVR and FDR data had been overwritten but the QAR data retrieved by Japan Airlines was made available to the Investigation team.
It was established that the First Officer had been acting as PF and that both pilots had been in and out of Singapore four times. The Investigation did not note the overall or aircraft type flying experience of the two pilots involved or the Captain's time in command.
The PF pre-departure briefing included the taxi route he expected to get which involved arriving at the expected departure runway 20C via taxiways NC3 and EN (see the diagram below). When the clearance was actually given, it involved arriving via taxiway NC2, EP and EN.
In accordance with standard ATC operating procedures at night or in low visibility with a fully serviceable lit centreline control system available, the clearance was given as usual by switching on the lit centreline for the required route and instructing the aircraft to "taxi on the greens" - as three other departing aircraft had earlier done.
On transfer to the TWR controller, the crew confirmed that they were ready for take-off and were requested to expedite taxiing. As the aircraft continued taxiing on NC2 and passed taxiway A7, clearance to line up and take off on Runway 20C was given. The aircraft completed the right turn onto taxiway EP and the First Officer was reported to have called "runway heading check" which the Captain subsequently stated he had assumed meant that the First Officer "had verified that the aircraft was lined up on the runway in accordance with the take-off procedure in the Operator’s Aircraft Operating Manual". What this Manual actually required was found to be "before entering the departure runway, verify that the runway and runway entry point are correct”, and “verify that the airplane heading agrees with the assigned runway heading”.
Take-off was then commenced and the aircraft crossed the lit red stop bar on taxiway EP. The TWR controller observed what was happening and instructed the aircraft to stop which it did before reaching taxiway A3. This instruction was found to have been given prior to the commencement of a rejected take-off. The maximum speed reached was not published.
During the course of a review of the sequence of events, the Investigation concluded in respect of the performance of the flight crew that:
- Having attempted to guess the likely taxi route rather than more openly consider the possibilities, the First Officer "appeared to have fixated on this mental picture of taxi route (i.e. one single and gradual right turn to enter R20C)".
- The First Officer "seemed to have been so fixated that he missed the red stop-bar lights on EP at the EP/E1 intersection and the fact that there were still green lights ahead for him to follow that would have guided him to turn left onto EN".
- Neither pilot appeared to have noticed "the lack of runway lighting and markings (e.g. threshold and runway edge lights; runway designator, runway taxi-holding position markings) which identify a runway".
- When pilots are instructed by the ATC to follow the greens, "they should still monitor the progress of the taxiing and ensure they know where they are on the taxi route" whereas in this Serious Incident, neither pilot appeared to "monitor the taxiing by, for example, cross-checking with the outside cues and aids, to ensure that they reach the correct runway entry point".
- It appeared "that effective communication and coordination" between the two pilots "was lacking".
- There was no evidence that the Captain was effectively fulfilling the role of PM during the taxiing of the aircraft.
It was noted that the airline involved used the LOSA process to monitor the day-to day performance of its flight crew.
The Investigation also considered ways in which the resilience of the current departure taxi procedures might be enhanced and concluded that:
- In respect of taxi clearances, it was considered that there may be a case for "verbalising the specific taxi route" so that "any inconsistency between the verbalised taxi route and the taxi-on-the-greens route may also be spotted by flight crews, thus affording opportunities for clarification and correction".
- In respect of take-off clearances, it was noted that these are "usually given to an aircraft when it is approaching the departure runway" on the rationale that at this stage "aircraft should be closely watched as they approach this position to ensure that they are taxiing to the correct runway before a take-off clearance is issued". It was considered that "it would be advisable not to issue line up and take-off clearances in one transmission" because separating them would give a controller "a chance to monitor the aircraft’s movement to ensure that it is on the right route to the departure runway" and introduce "another line of defence" against an aircraft crossing a clearly illuminated red stop bar as in this event.
- In respect of the specific taxi clearance given in the investigated event, it was considered that "it would be prudent […] to issue the take-off clearance only after seeing that the aircraft has turned left from EP onto EN".
Safety Action taken as a result of the Serious Incident and notified to the Investigation included the following:
- Japan Airlines introduced a new taxi procedure aimed at "preventing its flight crews from losing situational awareness during taxiing". This new procedure established the following rules, among others, for both pilots:
- PF shall understand the ATC’s instructions and always control the aircraft with correct awareness of its position, using outside visual information (e.g. sign boards) primarily.
- PM shall monitor the aircraft’s navigation, its present position and taxi route, and the ground speed with reference to charts or Airport Moving Map.
- PM shall call out the name of next taxiway to turn, its turning direction, and its present ground speed before aircraft reaches the turn.
- When instructed by the ATC to hold short of (a) runway holding point, hold line, or a taxiway, PM shall call out the position to hold and the present ground speed whenever PM has the hold position in sight.
- PF shall stop the aircraft immediately whenever situational awareness of both PF and PM does not agree, or if any doubt is felt (e.g. when there is no callout from PM, even though approaching the taxiway to turn or the hold line to hold).
- ATC Singapore subsequently classified the area where the incident took place as a 'hot spot' and promulgated this information accordingly. Watch Managers were also instructed to brief controllers to be "aware of the possibility of pilots mistaking a parallel taxiway as a runway, especially in situations when pilots need to taxi through a number of turns to reach the runway entry point" and "to consider separating line up clearance from take-off clearance".
One Safety Recommendation was made as a result of the Investigation as follows:
- that Singapore Changi ATC consider verbalising the main taxi route in addition to the instruction to “taxi on the greens” in the taxi clearance. [R-2016-005]
The Final Report of the Investigation was published on 29 July 2016.
- Wrong Runway Use: Parallel Taxiway Use
- Active Ground Lighting Control
- Taxiway Lighting
- Low Visibility Procedures (LVP)
- Taxiway Surface Markings and Signs
- Runway Incursion Prevention - Runway-holding Position, Stop Bars and ATC Clearance
- Situational Awareness
- Cross-checking Process
- Pilot Perception
- Safety Culture
- Line Operations Safety Audit (LOSA)