Aviation regulator, the Directorate General of Civil Aviation (DGCA), had asked Jet Airways and SpiceJet to take corrective action to address possible issues with their Boeing 737 MAX planes, which could lead to "significant altitude loss" of the aircraft, a senior official said on Thursday.
The warning prompted the US Federal Aviation Administration to issue its own emergency airworthiness directive, telling airlines with Boeing 737 Max 8 aircraft to follow correct procedures if pilots receive erroneous information from an AOA sensor.
On Tuesday, Boeing issued a bulletin to all airlines and pilots who operate the 737 MAX.
Boeing said that the warning directs operators to "existing flight crew procedures to address circumstances where there is erroneous input from an AOA sensor".
While the ultimate cause of the crash is still under investigation, Boeing has previously provided guidance on how pilots should deal with extreme nose down incidents.
The new details - gleaned from a recovered flight data recorder - come after the government said it was launching a "special audit" of the budget carrier's operations. The error erroneously tells pilots that there's a stall in airflow, triggering an automated system that points the plane downward in an effort to regain speed. The AD now affects 246 total Boeing 737 MAX aircraft in service globally. "Safety is the top priority at Southwest, and we will continue to work closely with Boeing and the FAA to maintain the integrity of our fleet and validate our operating practices".
Boeing, which manufactured the Lion Air plane, issues safety-related bulletins, and had previously circulated instructions about what flight crews should do if sensors fail.
The Boeing 737 MAX 8 then made another flight to Jakarta that same day, and the pilots reported further problems.
According to USA Today, Boeing has delivered more than 200 models of the Boeing 737 and has received more than 4,500 orders. When the AOA sensor input to the computer is erroneous, it can result in a trim of the stabilizer to a nose down position in increments lasting up to 10 seconds.