Lion Air Flight 610: final accident report highlights nine contributing factors that resulted in tragedy

By Antonia Molloy - October 31, 2019

It is just over a year since Lion Air Flight 610, a Boeing 737 MAX 8 aircraft, crashed into the Java Sea 13 minutes after take-off from Soekarno-Hatta International Airport in Jakarta, killing all 189 passengers and crew. The final report into the accident, published this month, has concluded that manufacturer Boeing was the catalyst for the series of events that culminated in the tragedy – but the disaster would not have occurred without other factors.

The Indonesian National Transportation Safety Committee’s (NTSC) final report, published on 25 October 2019, listed nine contributing factors for the accident. It describes these as "...actions, omissions, events, conditions, or a combination thereof, which, if eliminated, avoided or absent would have reduced the probability of the accident or incident occurring, or mitigated the severity of the consequences of the accident or incident".

These included:

  • "MCAS (Manoeuvring Characteristics Augmentation System) was designed to rely on a single AOA (Angle of Attack) sensor, making it vulnerable to erroneous input from that sensor."
  • "Lack of documentation in the aircraft flight and maintenance log about the continuous stick shaker and use of the Runaway Stabilizer Non-Normal Checklist (NNC) meant that information was not available to the maintenance crew in Jakarta nor was it available to the accident crew, making it more difficult for each to take the appropriate actions."
  • "The multiple alerts, repetitive MCAS activations, and distractions related to numerous ATC communications were not able to be effectively managed. This was caused by the difficulty of the situation and performance in manual handling, NNC execution, and flight crew communication, leading to ineffective CRM application and workload management. These performances had previously been identified during training and reappeared during the accident flight."

    The report stressed that these factors were not listed “to show the degree of contribution”: a point that was reinforced by Nurcahyo Utomo, an investigator for the Indonesian NTSC, at a news conference in Jakarta. The New York Times reported that Mr Utomo said: "The nine factors have to happen together. If one of those nine contributing factors did not happen, the crash would not have happened."

    Less than five months after the Lion Air Flight 610 crash, Ethiopian Airlines Flight 302 crashed near the town of Bishoftu, six minutes after take-off from Addis Ababa Bole International Airport in Ethiopia – the aircraft was also a Boeing 737 MAX 8.

    Boeing has faced an ongoing crisis in the wake of the two disasters. The company’s latest quarterly profits have dropped by more than half (53 per cent) and the Boeing 737 MAX 8 remains grounded, meaning that the company has been unable to deliver any aircraft or receive any payments for new aircraft. However, Boeing has been working extremely hard to deliver a permanent fix for the problem and expressed optimism that the aircraft will receive US approval before the end of 2019.

    Commenting on the Indonesian NTSC report into the Lion Air crash, Professor of Safety and Accident Investigation Graham Braithwaite said: "This is a very important investigation that seeks to identify where lessons can be learned rather than to allocate blame. There is a lot of valuable information that can be used by manufacturers, regulators, airlines and across the aviation industry to improve the way that aircraft are designed and operated. The 737 MAX 8 issue has highlighted systemic issues of relevance to the whole of the industry - it is not just a Boeing problem. More than ever, we need to work together to continuously improve aviation safety."