Complex chain of events caused Lion Air 737 MAX crash

A complex chain of events caused the fatal crash of a Lion Air 737 MAX in October last year, according to the final report published today by Indonesian investigators.

The 353-page report identified nine factors which contributed to the crash, which killed all 189 passengers and crew on board.

These included bad design, parts that had not been properly tested, poor communication between flight crew, and inadequate flying skills.

At a press conference, Indonesian air accident investigator Nurcahyo Utomo told reporters that perhaps if one of the nine things had not occurred, the tragic accident might not have happened.

The report claimed there were strong indications that a critical sensor, which provides data to the MCAS anti-stall system, had been miscalibrated by a repair shop in Florida and had not been properly tested during installation by Lion Air maintenance staff.

It also said Lion Air should have grounded the jet following faults on earlier flights, and noted that 31 pages were missing from the airline’s October maintenance logs.

It said the captain had not properly briefed the first officer when handing over control just before the plane entered its fatal dive.

According to the cockpit voice recorder, the captain spoke of having the flu and the first officer told the captain the flight was not in his initial schedule and he had been called at 4am to be told of the rota change.

Lion Air has declined to comment.

Boeing issued a statement saying it was addressing the report’s recommendations and taking actions to enhance the safety of the 737 MAX.

The aircraft has been grounded since March after a second fatal crash by Ethiopian Airlines.

Boeing president & CEO Dennis Muilenburg said: "We are addressing the KNKT’s safety recommendations, and taking actions to enhance the safety of the 737 MAX to prevent the flight control conditions that occurred in this accident from ever happening again.

"We value our long-standing partnership with Lion Air and we look forward to continuing to work together in the future."

It said since the crashes, the 737 MAX and its software have been undergoing an ‘unprecedented’ level of global regulatory oversight, testing and analysis.

In the past few months Boeing has been making changes to the 737 MAX and has added an extra level of protection to sensors for the MCAS flight control software, he said.

"In addition, Boeing is updating crew manuals and pilot training, designed to ensure every pilot has all of the information they need to fly the 737 MAX safely," said Boeing.

Boeing expects the 737 MAX to resume flying before the end of this year.