On 2 January 2024, an Airbus A350-900 (JA13XJ) being operated by Japan Airlines on a scheduled domestic passenger flight from New Chitose to Tokyo Haneda as JA516 had just made a night touchdown in Visual Meteorological Conditions (VMC) on runway 34R when it collided with a Bombardier DHC8-300 (JA722A) being operated by the Japanese Coast Guard.
An interim report has been issued and the investigation is still ongoing when this article is written. Skybrary published an article analysing and summarising the report. This article focuses exclusively on the Air Traffic Control (ATC) related aspects of the accident. The factors that contributed to the accident are:
- Misunderstanding of the clearance given by ATC to the crew of the DHC8, leading them to enter the runway without being cleared to do so
- The DHC8 entered the runway at a taxiway intersection where stop bars had been inoperative for months. This intersection is not used often and the DHC8 could use it to get priority and take-off before other regular flights, given the urgent nature of its flight: transporting cargo as part of a relief operation
- The Trajectorised Airport traffic data Processing System (TAPS), an ATC support system, detected the runway incursion but the Air Traffic Controller (ATCO) was not using it routinely, as the airport was operating under VMC conditions
- The TAPS had no audible alert, only a visual alert.
Questions raised by the interim report’s content
Beyond those factors, the interim report by the Japan Transport Safety Board dives deeply into one key factor: how much ATCOs knew about the TAPS. The following excerpt of the report is very telling: “At the time of the accident, at Tokyo Airport Traffic Control Tower, there were no regulations stipulating how to handle situation when the warning by the support system was issued and no trainings based on the curriculum were conducted. In addition, there were no materials and others to provide air traffic controllers with knowledge of the principles behind the warnings by the support system.”
This shows a critical disconnect between the persons deciding to implement a system like TAPS, those in charge of putting it in place, those in charge of training, and the final users. Each of them had a chance for raising questions to either get better functionality (audio alarms) or better training.
The feedback of ATCOs (designated as Tower East, Ground East and TC in the following excerpt of the report) is also very clear about the use and performance of the system:
“Tower East had always found the support system difficult to reply on, as it sometimes displayed warnings even when runway occupancy was not actually overlapping and in addition there was no sound alarms, and did not consider it to be a system that would support visually situational awareness. Even when the accident occurred, Tower East did not recognize whether a warning by the support system was displayed or not.
Ground East also felt that the support system often displayed warnings in situations that had nothing to do with the actual runway occupancy status, and that it was incompetent as a system to support visually situational awareness. Even when the accident occurred, Ground East did not recall any warnings by the support system being displayed. TC also considered, as the same reason as Tower East and Ground East, that it did not function as a support system, and normally did not expect to take any action even if TC saw a displayed warning. Even when the accident occurred, TC did not recall seeing a displayed warning by the support system.”
The fact that the controller considered that “it was incompetent as a system to support visually situational awareness” goes back to a critical factor with safety net functions: the error rate. An error occurs when the safety net triggers when there is no reason to, or when it does not trigger when there is a reason to. If a safety net error rate is too high, ATCOs rapidly lose confidence in it and start ignoring the alerts.
Just culture as the basis for safety
It would be interesting to know if ATCOs reported problems with using the TAPS in VMC and if so, what happened with those reports, or if the issues ever were reported. The latter could have two causes: no report because ATCOs assume they would be ignored anyway, or no report because of having the reporter blamed.
Japan’s workplace culture is hierarchical and conservative and failure tends to be stigmatised, and saving face is very important. ATCOs may be reluctant to self-report errors unless absolutely necessary, out of fear of blame – even if their intentions were good. After a serious incident in 2001, two ATCOs were assigned to non-operational duties, until a verdict was rendered and then dismissed after being recognised guilty.
Japan has been slower to embrace “just culture” formally. As a signatory to ICAO and a participant in Asia-Pacific safety programs, Japan is working toward it. However, the legal framework still allows administrative punishment without protections that exist under a robust just culture model, like EASA’s Regulation 376/2014 in Europe.
Japanese ATC associations call for support
The representatives of the Japan Federation of Air Traffic Controllers and of the Air Traffic Control Association, Japan presented their perspective on the Haneda case at the latest IFATCA assembly. From their report, it seems that just culture did not progress a lot in Japan and that a frequent reaction from management and the general public is that “if the controller worked in a more strenuous way, the accident would have been avoided”.
They called other members for support and guidance on how to improve just culture in Japan, not only in a general sense but in the context of the Haneda accident.
Just culture is not a get-out-of-jail-free-card
An important step in understanding and applying just culture is that it is a means to gain insights and information which would otherwise not be available. By nature, incidents are often known only to front-line operators and if they are not given a way to report them in a safe manner, they won’t report them at all. This is the principle at heart of just culture. Just culture does not provide immunity in cases of gross negligence or malevolent intent.
To learn more about just culture, listen to this episode of Radar Contact with Mario Winiger and Melanie Hulliger of Skyguide.
