Boeing found debris from manufacturing in stored 737 Max jets, a problem that has plagued the company on a different plane

• Boeing has found debris, likely left over from manufacturing, in several stored 737 Max aircraft, Leeham News reported.
• The items, known as foreign-object debris, or FOD, were in the planes' fuel tanks. Boeing will inspect all 400 finished, undelivered airplanes for FOD.
• Boeing has been plagued by quality-control issues on other aircraft, and has been accused of prioritizing delivery deadlines over safety in manufacturing.
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Boeing has discovered foreign objects in the fuel tanks of some undelivered 737 Max aircraft, according to a new report from Leeham News.

The items were considered foreign-object debris, or FOD, Leeham reported. FOD consists of items left over from manufacturing, such as tools, rags, or spare parts.

FOD is usually found during inspections before delivery to airline customers.

However, problems involving FOD have plagued Boeing at the North Charleston, South Carolina factory that produces the 787 Dreamliner wide-body aircraft. An April New York Times investigation found claims of shoddy production and poor quality control, and airlines complained to Boeing about quality issues in delivered aircraft in 2019.

Boeing has faced criticism that it rushed development of the 737 Max in order to catch up with its rival Airbus, which had unveiled an updated version of its successful A320 family of planes.

It has also been accused of prioritizing delivery deadlines over safety at various manufacturing sites, including the Renton, Washington, factory where the 737 Max is built, leading to missed problems and production mistakes, including FOD.

Boeing will inspect all 400 stored, undelivered 737 Max planes before they're delivered to customers, Leeham reported. The inspections are reportedly unlikely to delay the plane's return to service.

Boeing is already planning to perform extensive maintenance checks and tests on stored aircraft when the grounding ends. Business Insider first reported in September that the plane-maker was reaching out to retired technicians for help getting the planes ready for delivery quickly.

The FAA was notified about the FOD discovery, Leeham reported. The issue is unrelated to the technical problems that have grounded the 737 Max for nearly a year.

Boeing did not immediately return Business Insider's request for comment.

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