How Boeing Is Tackling Its Quality Control Issues
By Louis Hardiman
Almost two years ago, Boeing’s 737 MAX program was almost struck with another disaster when an Alaska Airlines flight had to divert after a sudden blowout of an emergency exit door plug. Since then, Boeing has announced a “war on defects”, greatly improving its quality control regime to ensure that faulty Boeing 737 MAX aircraft don’t take to the skies, as reported by The New York Times.
We revisit the Alaska Airlines incident and the resulting quality control developments below. We then cover other changes made to improve Boeing’s working culture and simplify manufacturing processes. Boeing hopes that these steps will improve 737 MAX safety and allow production to accelerate. It will be fascinating to see how these lessons learned from the MAX will be translated onto the delayed 777X program.
The Incident That Sparked The Changes
On 6 January 2024, a Boeing 737 MAX 9 operated by Alaska Airlines diverted to Portland International Airport (PDX). A mid-aft door plug, a window, and an unoccupied seat were lost mid-flight. These issues caused a rapid decompression, forcing the crew to make an emergency landing. All 171 passengers and crew members survived the flight, and there were just three minor injuries.
Despite the lack of injuries sustained in the incident, many cabin crew and passengers were shaken up by what they had been through. One member of the cabin crew said, “We got so lucky. When this is all said and done, investigations are over … how can we know this is not going to happen again and this is safe? Because that should not have happened.” “I was absolutely certain that we had lost people out of the hole and that we had casualties,” another said.
Changes On The Production Line
Boeing began by limiting the tasks performed out of order. Known as “traveled work”, this practice makes mistakes much less likely as the usual procedures aren’t followed. Such tasks have fallen by 75% since February 2024.
Previously, mechanics had just illustrations from engineers when checking an aircraft. Daily and weekly reviews are also used to identify persistent problems. Now, they have a selection of high-definition imagery. It is important to note that engineers and mechanics were doing a lot of these processes already, but these have now been standardized and made more robust. Jennifer Boland-Masterson, the director of 737 manufacturing operations, said: “We have really homed in on our feedback loops. The goal is to permanently fix it.”
Another significant change has been a change in working location for the 737 MAX’s final touches. Previously, these last steps before an aircraft is delivered were conducted outside. Many almost-complete aircraft were parked by the lake at the Boeing site. Now, this work has been moved inside so it can be completed in a meticulous, orderly environment.
Boeing’s Working Culture
Establishing better processes is only half of the story. It is ultimately workers on the factory floor who complete the work and determine if an aircraft can fly safely. Kelly Ortberg, Boeing’s chief executive, has acknowledged that there has been too much distance between Boeing’s corporate and manufacturing teams.
Boeing is taking substantial steps to bring its rank-and-file and management closer together. This includes an hour put aside each week for employees to raise defects and constraints with managers. There is then a collaborative process to fix any issues. The New York Times spoke with the production manager, Glenda Heggie. She recalled an incident where workers reported racks holding electrical components were arriving with missing and misaligned holes. She then arranged a solution with Boeing’s engineers. Jon Holden, the president of District 751 of the International Association of Machinists and Aerospace Workers, said: “They’re definitely moving in the right direction. Now, we just need to see that month after month, quarter after quarter, year after year.”
Reducing Production Complexities
Aircraft manufacturing is a ridiculously complex process, involving thousands of parts, and the consequences of getting it wrong are unimaginably horrific. It is no surprise that reinstalling the Alaska Airlines 737 MAX’s door plug bolts got lost in this high-stakes and confusing environment. Boeing is working to reduce such incidents by simplifying its complicated documentation. It is getting assistance from other industries that have to address complex challenges, such as the pharmaceutical industry.
The manufacturer has also been bringing in measures to track parts. Examples include testing of tracking devices and scanners. The factory floor also now uses locked racks so that parts are safely stored in between shifts and cannot be misplaced.
There is also an undeniable need for Boeing to upgrade its workforce so that it can better deal with the complexities that cannot be avoided. Boeing’s workforce has been declining in experience, but the manufacturer has historically failed to address this issue. A National Transportation Safety Board report found that, over the last decade, the number of Boeing employees with over 10 years of experience has fallen from 50% to 25%. Recently introduced programs that have expanded training by two weeks are beginning to fill this gap.
Improving Manufacturing Processes Isn’t Only About Safety
Standardizing and simplifying production processes and introducing better quality-control checks aren’t just about making Boeing jets safer. It is also essential for the company to address the commercial disasters it has faced in recent years, including vast sums of money lost due to the 737 MAX groundings and the ongoing 777X delays. Boeing currently has a backlog of well over 4,000 737 MAX orders, meaning there is a lot of money on the table for the manufacturer if it can fulfil these orders.
The table below shows the number of Boeing 737 MAX aircraft delivered year-on-year, showing significant declines at points that have resulted from the program’s accidents and incidents:
| Year | Boeing 737 MAX Deliveries |
|---|---|
| 2018 | 580 |
| 2019 | 127 |
| 2020 | 43 |
| 2021 | 263 |
| 2022 | 387 |
| 2023 | 396 |
| 2024 | 265 |
| 2025 (as of September 2025) | 198 |
Airlines Are Also Waiting On The 777X
Churning out 737 MAX aircraft that pass rigorous quality control checks isn’t the only pressure that Boeing’s engineers and mechanics are under. They also need to build 777X aircraft and pass the remaining certification steps. The aircraft has a number of customers with sizable orders, including Emirates, which has 205 on order, who are becoming increasingly frustrated.
Production will ramp up once Boeing receives the long-awaited certification for the 777X. Plans are to reach a combined 777/777X production rate of four aircraft per month. This small number is to ensure that proper checks and procedures can be followed to avoid repeats of quality and structural issues. Whether Boeing can deliver on its lengthy 777X order sheet without the disasters and incidents that faced the 737 MAX remains to be seen.




