Indonesian investigators have released their first report on last month’s doomed Lion Air flight.

Indonesian investigators have released their preliminary report on the ill-fated Lion Air Flight 610, which crashed into the Java Sea killing all 189 people aboard last month.

According to flight recorder data obtained by Indonesia’s National Transportation Safety Committee (KNKT), the pilots failed to deactivate a faulty safety system used to point the aircraft’s nose downward to avert stalling.

The disaster was prompted by a technical glitch: Inaccurate readings indicated the plane’s nose was too high. The aircraft interpreted the erroneous message as a cause to activate its “automatic aircraft nose down” feature, ultimately prompting its disastrous plunge into the ocean. Pilots reportedly made over two dozen attempts to regain control of the plummeting aircraft, but failed, losing radio contact and crashing just 13 minutes after taking off from the capital city of Jakarta.

Nurcahyo Utomo, head of the Indonesia transportation safety committee, said it’s clear the aircraft shouldn’t have been permitted to leave the tarmac. “In our view, the plane was not airworthy,” he said on Wednesday.

The crash came despite numerous warnings. The doomed Boeing 737 Max 8 aircraft had experienced the same technical glitch on several previous flights, including the day before. Pilots on that route, however, were able to turn off the maneuvering characteristics augmentation system (MCAS) and guide the plane to safety.

There were other issues pervading the aircraft, pertaining to its airspeed and altitude sensors, the report noted. Similarly, an “angle of attack” sensor used to measure airspeed over the aircraft’s wings had been replaced a day before.

In the disaster’s immediate aftermath, pilots for several airlines placed blame on Boeing for reportedly failing to provide information about the anti-stalling feature in its Max 8 and 9 aircraft. Boeing, for its part, updated its safety bulletin with information on how to disengage the system.

On Wednesday, the manufacturer stood by its aircraft. In an effort to reassure customers who might board one of the 200 737 Max planes currently in service, the company wrote:

The company currently faces lawsuits from victims’ families, while Indonesian authorities will continue to work with U.S. agencies as part of an ongoing joint investigation.

Sharing is caring!