RENTON, Washington – The 737 Max starts its journey through a Boeing factory near Seattle when its empty central tube is hoisted onto a structure high above the floor. There, about a dozen workers fan out to search for defects.

That inspection is part of a new quality-control regimen at Boeing after a nightmarish episode nearly two years ago, when a part on a Max blew away at 15,000 feet (4,570m), exposing passengers to roaring winds and potential catastrophe. No one was seriously injured, but the January 2024 episode prompted a reckoning.

Boeing installed new management and made wide-ranging changes at this factory in Renton, on the shore of Lake Washington. Some improvements were straightforward, such as tightening equipment arrival inspections, doing more jobs in their intended order and simplifying paperwork – changes that some aerospace experts say should have been made long ago. Other problems will be more difficult to address, like winning over workers who have complained for years that the company was prioritising speed over quality.

But the reforms are clearly having an effect. Some airlines that buy Boeing planes say quality has improved. And in recent months, the Federal Aviation Administration has eased some restrictions it imposed on Boeing after the 2024 episode and two Max crashes that killed 346 people in 2018 and 2019.

Even as they noted their progress, Boeing executives acknowledged during a recent daylong tour of the factory that there was more to do. The company will have to continue to improve quality as it tries to produce planes faster.

“We’re right in the middle of the field, and we’ve got a long way to run,” said Ms Katie Ringgold, vice-president and general manager of Boeing’s 737 programme and that factory.

The body of the Alaska Airlines plane that lost a part in 2024 arrived at Boeing’s factory in August 2023. Workers there soon discovered damaged fasteners near an emergency exit that the airline didn’t plan to use. To stay on schedule, the problem was noted and the plane moved on to the next stage of production.

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