The crash is said to be a blow to the country's aviation safety record after the lifting of bans on its airlines by the European Union and US.
Boeing said Monday that it's working closely with investigators and taking every measure "to fully understand all aspects of this incident".
According to a report in The Wall Street Journal Monday night, what the company did not tell operators and flight crews is that the stall-prevention system may, under certain unusual circumstances, unexpectedly push the plane's nose down with such force that the crew can not pull it back up.
Flight JT 610 with 189 people aboard crashed into waters off West Java province shortly after taking off from the worldwide airport in Jakarta late last month.
One of the pilots of the plane was Bhavya Suneja, an Indian from Delhi.
The U.S. Federal Aviation Administration and Boeing Co are evaluating the need for software or design changes to 737 MAX jets in the wake of last month's deadly Lion Air crash in Indonesia, the regulator said on Tuesday. The Wall Street Journal said Boeing didn't disclose MCAS details to cockpit crews because it was anxious about overwhelming them with more technical detail than needed or could digest.
According to sources at two airlines operating the MAX series, the system in question is called Maneuvering Characteristic Augmentation (MCAS) and is meant to improve pitch response at high angles of attack. After that Intan couldn't hold them in any more.
"The companies and the pilots should have been informed", Jon Weaks, president of the Southwest Airlines Pilots Association, Bloomberg. "The bottom line here is the 737 MAX is safe and safety is a core value for us". The FAA is part of a joint investigation conducted with the National Transportation Safety Board (NTSB) and Indonesian authorities, according to an FAA press release.
The directive warned pilots that a computer on the Boeing 737 MAX could lead to the plane being forced to descend sharply for up to 10 seconds even in manual flight, leading to potential difficulties in controlling the plane.
Critics point to Boeing's attempt to limit airlines' transition costs-and stay competitive-as the reason it failed to impart crucial safety data.
Investigators are already examining the flight data recorder (FDR) that was pulled off the sea bed, some 30 meters under water, on November 1.
Passengers on that flight told CNN that the plane experienced a significant drop in altitude shortly after takeoff. About 15 minutes into the flight, which took off from Jakarta, the plane plunged into the sea.
Once in Jakarta, a Lion Air technician checked the plane again and gave it the green light to fly on its final flight, from Jakarta to Pangkal Pinang.