(Bloomberg) -- The certification of the Boeing 737 Max was based on incorrect assumptions as a flight-control system was over-reliant on a single sensor, making it vulnerable to malfunctions, Indonesian investigators told families of the victims of last year’s Lion Air crash.

The National Transportation Safety Committee flagged problems associated with the Maneuvering Characteristics Augmentation System, or MCAS, according to photographs of a slideshow to the families gathered in Jakarta, which is ongoing. The MCAS was also implicated in the crash of an Ethiopian Airlines 737 Max jet in March.

The final report into the crash, which has yet to be formally released, could influence regulators worldwide as they assess the fate of Boeing Co.’s best-selling plane. The jet has been grounded globally since March 13. Lion Air flight 610 plunged into the Java Sea about 13 minutes after take-off on Oct. 29, 2018. All 189 people on board were killed.

To contact the reporter on this story: Harry Suhartono in Jakarta at hsuhartono@bloomberg.net

To contact the editors responsible for this story: Young-Sam Cho at ycho2@bloomberg.net, Will Davies, Emma O'Brien

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