Indonesia will release its first report on the deadly crash of Lion Air tomorrow

Indonesian investigators will present their first report on the Lion Air crash on Wednesday, a month after the all-new Boeing 737 crashed at sea, killing 189 passengers aboard the country's second-largest air disaster.

The report, which comes as the search for the voice recorder in the cockpit continues in the Java Sea, should not draw any definitive conclusions from the ongoing investigation into the problem. accident of October 29th.

However, investigators indicated that they were focusing their attention on the Boeing 737's anti-stall system.

The convicted aircraft systems had detected that he was stuck because of a defective indicator and had warned the captain through the intermediary of a "shaker" who was doing so. vibrate orders, Nurcahyo Utomo, investigator of the Indonesian Committee for Transport Safety (KNKT), told parliament. the week.

The Maneuverability Enhancement System (MCAS) – a new automatic modification of the crashed model – activated and stuttered to prevent a stall, Utomo said.

The pilots successfully countered this for a period of time before the aircraft entered the final dive, he added.

The same anti-stall system was activated on the plane during a flight performed the night before, but the pilots in this case managed to extinguish it, said Mr. Utomo.

This accident was the first involving the latest model from Boeing's successful 737 series, the 737 MAX, which came on stream a year ago.

According to the KNKT, MCAS was not described in the Lion Air flight manual prior to the accident, nor in those used by US airlines, according to the US pilot unions.

However, the cockpit procedure for handling a trailing stabilizer remains unchanged from the previous 737 models.

Boeing chief executive, Dennis Muilenburg, said earlier this month that Boeing was providing "all the information needed to fly our planes safely," but that the aircraft manual and training methods were examined after the crash.

In response to initial findings from the jet flight data recorder, Boeing sent airlines a bulletin reminding them of the procedures to follow and advising them to add MCAS information to the flight manuals.

A spokeswoman for Boeing declined to comment on the investigation, but said Boeing had discussed MCAS's functions with more than 60 airline operators around the world since 2016.

The maintenance practices and training of Lion Air pilots are also under scrutiny after investigators report that the convicted jet had speedometer problems on its last four flights.

Lion Air, one of Asia's largest low-cost carriers, said its security concerns had been highlighted in previous incidents.

Most air accidents are caused by a multitude of factors and investigations last an average of one year.

Investigators must limit their report to the factual details of the jet flight data recorder, which contains 69 hours of information on its last 19 flights.

But they can include immediate recommendations if they have urgent security concerns.

The search for the cockpit voice recorder is proving difficult after investigators said last week that its "ping" signal was no longer detected.

"We are still making efforts to find the TRC and it is very important.The TRC is linked to the credibility of the country so that we can avoid the same incident," said KNKT President, Soearjanto Tjahjono, in parliament .

(With the exception of the title, this story was not changed by NDTV staff and is published from a syndicated feed.)