- The final report into the Lion Air Boeing 737 Max crash that killed 189 people blamed Boeing’s design of the plane while also pointing to errors by the airline and its crew.
- It said that the design of the controversial MCAS software, which continually pointed the plane’s nose down, “did not adequately consider the likelihood of loss of control of the aircraft,” and that Boeing should have added a fail-safe system.
- The report also criticised Boeing for not informing pilots about the system and for a design issue that would keep a warning light about the plane’s angle in the sky from working.
- The report also pointed to pilots, saying the crew responded poorly to a series of alerts and the first officer could not recall a checklist he should have memorized.
- It said that Lion Air should have grounded the plane after similar issues were found on a previous flight and that 31 pages were missing from the plane’s maintenance logs that month.
- Lion Air did not appear to have inspected a key sensor that turned out to be faulty, it also noted.
- Visit Business Insider’s homepage for more stories.
Investigators’ final reportinto the October 2018 crash of a Lion Air Boeing 737 Max plane that killed all 189 people on board said the plane’s design contributed to the crash, alongside actions of the airline and its pilots.
Investigators in Indonesia, where Lion Air is based, pointed to the plane’s anti-stall software, called MCAS, which a preliminary report identified as the reason the plane’s nose continually pointed down out of the pilots’ control, causing it to nosedive into the sea.
Flight 610 crashed into the sea 13 minutes after it took off from Soekarno-Hatta International Airport in Jakarta, Indonesia, on October 29, killing everyone on board.
“The design and certification of the MCAS did not adequately consider the likelihood of loss of control of the aircraft,” the report said.
“A fail-safe design concept and redundant system should have been necessary for the MCAS.”
The report also highlighted that Boeing ultimately gave MCAS more power than what it had originally told regulators, a development first reported by The Seattle Times in March.
The report said this meant the US Federal Aviation Administration “would not be able to reassess the safety of the design change.”
The preliminary report into the crash in April found that the MCAS system had misfired. A preliminary report into a second crash, in which a 737 Max operated by Ethiopian Airlines crashed and killed 157 people in March, reached the same conclusion. Boeing is updating the plane, which has been grounded since March, but has defended its design as safe.
The updates have not been approved by the FAA or its equivalent regulators around the world.
The final report, released Friday, criticised Boeing for not including details about the MCAS software in manuals and training for the plane’s pilots.
“The absence of information about the MCAS in the aircraft manuals and pilot training made it difficult for the flight crew to diagnose problems and apply the corrective procedures,” the report said.
An audio recording from a meeting between American Airlines pilots and Boeing executives after the Lion Air crash that was shared with Business Insider showed the pilots confronting Boeing for not sharing details about the system.
“I would think that there would be a priority of putting explanations of things that could kill you,” one pilot then said.
Boeing’s CEO defended not telling pilots about the system in April, saying it was “fundamentally embedded in the handling qualities of the aeroplane” and was “not a separate system to be trained on.”
The report also criticised Boeing over a design issue that would keep a warning light about the plane’s angle in the sky from working.
In a statement after the release of the report, Boeing CEO Dennis Muilenburg said the company was “addressing” the investigator’s safety recommendations.
He added that Boeing was “taking actions to enhance the safety of the 737 Max to prevent the flight control conditions that occurred in this accident from ever happening again.”
“We commend Indonesia’s National Transportation Safety Committee for its extensive efforts to determine the facts of this accident, the contributing factors to its cause, and recommendations aimed toward our common goal that this never happens again,” he added.
Boeing is facing lawsuits from the families of those killed on the flight as well as the families of those killed on the Ethiopian Airlines plane.
Investigators also pointed to the pilots and the airline
The report was also critical of the action of Lion Air and its pilots, citing poor communication and solutions to previous issues with the same plane.
It said the crew members did not coordinate their responses to issues in the plane and the associated alerts and said the first officer, who had performed poorly in training, was not able to recall a checklist he should have memorized.
The captain had been wrestling with the plane’s controls, managing to pull it up from a nose-down position more than 20 times, before he handed them over to the first officer, the report said. Soon after, the plane crashed into the sea.
A March report in The New York Times said the pilots were unaware of the steps they needed to take to stop the crash.
The report also said Lion Air failed to ground the plane after its previous flight, when the plane had the same malfunction but an off-duty pilot managed to solve the problem. The April preliminary report found that that information was not passed onto the crew of the fatal flight.
Friday’s report said the previous flight “experienced multiple malfunctions was classified as a serious incident and should have been investigated.”
The report said 31 pages were missing from the plane’s maintenance logs from October, the month of the crash.
The report also said a critical sensor in the plane, supplied by a Florida company, was faulty during the fatal flight.
It said Lion Air appeared not to have tested the sensor when installing it as a replacement the day before the crash.
Maintenance records do not include any record of this sensor – an angle-of-attack sensor, which measures the plane’s angle in the sky – being tested by the maintenance engineer who installed it, the report said, though the engineer claimed that it had been.
The report said the investigation “could not determine with any certainty” that the installation was “successful.”