Indonesian investigators have found that design and oversight lapses played a key role in the crash of a Boeing 737 MAX jetliner that killed all 189 people aboard in October, according to a report.

The draft conclusions in what is expected to be the first formal government finding of fault also identify a host of pilot errors and maintenance mistakes as contributing to the Lion Air plane’s plunge into the Java Sea, sources told the Wall Street Journal.

The global fleet of about 400 MAX planes was grounded in March after two fatal nose-dives triggered by the misfiring of the automated anti-stall Maneuvering Characteristics Augmentation System, or MCAS, in the Lion Air plane and one from Ethiopian Airlines five months later.

All 346 people aboard both new planes were killed after the pilots lost control.

A Boeing spokesman did not comment on the Wall Street Journal report but said the plane maker continued to provide support to the investigating authorities as they complete their report.

Indonesian investigators — who have shared their findings with the US Federal Aviation Administration and National Transportation Safety Board — also declined to comment, except to say the final document is likely to come out in early November.

“For the time being we cannot comment since the final report is still being processed by the relevant parties so they can provide input,” Haryo Satmiko, deputy chairman of Indonesia’s National Transportation Safety Committee, told Agence France-Presse on Monday.

The NTSB plans to announce “around the end of the month” recommendations to improve pilot and crew training — and to the FAA’s certification process for new plane models, the Journal reported.

The FAA welcomed the scrutiny from safety experts and looked forward to their findings, it said in a statement.

“We continue to work with other international aviation safety regulators and will carefully consider all recommendations,” it said. “The FAA will incorporate any changes that would improve our certification activities.”

A panel of international regulators set up by the FAA is expected in the coming weeks to present a report critical of the relationship between Boeing and the agency, according to AFP.

On Monday, meanwhile, FAA administrator Steve Dickson is set to detail progress on MAX aircraft to international air regulators who are divided about returning the grounded jet to flight, Reuters reported.

The closed-door briefing in Montreal, Canada, will put representatives from about 50 countries in the same room, to share concerns about Boeing’s proposed software fixes and new pilot training.

The new FAA head has downplayed the chances of a consensus breakthrough, telling Reuters last week that the meeting was more “to provide regulators with the latest information.”

In both accidents, erroneous data to one of the angle-of-attack sensors led to the activation of the automated system that repeatedly pushed down the planes’ nose.

The MCAS software takes readings from two sensors, which determine how much the nose is pointing up or down relative to the flow of air.

When MCAS detects that the plane is about to reach the so-called critical angle of attack, at which point the wings can no longer generate lift, the system automatically pushes the nose down.

Paul Njoroge, who lost his wife, three children and mother-in-law in the Ethiopian crash, and Chris Moore, who lost his daughter, plan to hold pictures of victims outside Monday’s meeting, Reuters reported.

The FAA turned down their request to attend the meeting but Dickson agreed to meet the two men beforehand, said Nadia Milleron, whose daughter, Samya Stumo, also died in the Ethiopian crash.