The Lion Air plane that crashed last month killing all 189 people on board reportedly should not have been given the okay to take off. That’s according to the findings of an investigation by Indonesia’s National Transport Safety Committee (KNKT), which determined that the Boeing 737 Max plane was not airworthy and should have been grounded, the BBC reports.
The flight crashed just 13 minutes after takeoff–just minutes after the pilots asked air traffic control to let it return to the airport, a sign that there was likely a technical problem with the plane. In the wake of the crash, there were preliminary reports of technical issues on the plane’s previous flights, which caused flight delays. What’s more, the plane reportedly dropped suddenly several times in the first few minutes of its flight.
This new report suggests that Lion Air had put the plane back into service without properly fixing the problem. According to black box recordings, the pilots struggled to regain control of the plane. The investigators believe the issue was a malfunctioning anti-stall system designed to prevent a plane from pointing upwards at too high an angle, where it could lose its lift. The anti-stall system reportedly kept forcing the plane’s nose down, requiring the pilots to correct the problem by pointing the nose higher, until the system pushed it down again. This happened over two dozen times during the very brief flight, per the New York Times, until they finally lost control of the plane and it continued on its downward trajectory.
The 737 Max is a new version of Boeing’s original 737 and has become its fastest-selling plane. After the crash, Boeing issued a warning to all pilots flying its 737 MAX aircraft, giving guidance on what to do if the plane gives an erroneous reading from a sensor.
The warning came too late for the pilots on flight JT610–and the passengers, too.