Lion Air plane that crashed in Indonesia in late October shortly after takeoff "was no longer airworthy and it should not have kept flying," investigators said on Wednesday.
A preliminary report said that equipment failures and inadequate airline safety measures were contributing factors in the crash, but that it is still too early to pinpoint the exact cause.
Information collected from the flight's "black box" data recorder shows that the pilots struggled to control the airplane as an automatic anti-stall safety system kept pushing the plane's nose down.
"We still don't know yet, if it contributed or not," said Nurcahyo Utomo, an investigator at Indonesia's transport safety committee (KNKT). "It is too early to conclude for now."
Problems known before crash
On October 29, the Boeing 737 MAX disappeared from the radar 13 minutes into the flight and plunged into the Java Sea, killing all 189 people on board.
The pilots on the previous flight had also reported the same problem, but had de-activated the anti-stall system and continued to fly manually.
Investigators said the pilots had reported the problem and Lion Air carried out safety checks on the plane, but deemed it safe to fly before the disaster.
The black-box data also
showed a recurring issue with the plane's air-speed indicator and other important sensors, but the airline repeatedly allowed the plane to fly.
Room for improvement
The transport safety committee gave recommendations to Lion Air to improve its safety culture, in particular to increase pilots' knowledge of emergency procedures.
Budget airline Lion Air has become Southeast Asia's biggest carrier, despite a shoddy safety record and repeated complaints over bad service.
Indonesia's air-safety record has improved in recent years after the United States and the European Union recently lifted airspace bans on all of its airlines. The country recorded 40 fatal crashes in the last 15 years.
gs/amp (AP, Reuters, AFP)
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