General manager of Boeing's 737 program, Mark Jenks, called the discovery "absolutely unacceptable" in a memo to employees. Credit: Boeing.

Is Boeing’s 737 MAX jet jinxed? Already beset with numerous issues, yet another problem has reared its head, according to a report by Patrick Clarke in Travel Pulse.

On Tuesday, the company confirmed that it found debris contaminating the fuel tanks in “several” undelivered planes built in the past year, the report said.

According to the Associated Press, Boeing said it has already made adjustments to prevent the problem from recurring in the future, including stepping up inspections before fuel tanks are sealed to ensure no metal shavings, tools or other objects are left behind during assembly, which poses an increased risk of electrical short-circuiting and fires.

FAA spokesman Lynn Lunsford told the AP that the agency has “increased its surveillance based on initial inspection reports and will take further action based on the findings.”

General manager of Boeing’s 737 program, Mark Jenks, called the discovery “absolutely unacceptable” in a memo to employees, the report said.

According to The Guardian, debris was discovered in the wing fuel tanks of undelivered MAX planes during routine inspections at Boeing facilities in Washington state and Texas where the MAX jets are being stored.

The company has not disclosed how many planes were affected.

The company has had recent issues with debris – including tools and rags – found in its 787 Dreamliners and KC-46A military refueling tankers. Those issues have led to two suspensions of deliveries of KC-46As to the US Air Force, the report said.

However, the issue is not expected to delay the aircraft’s timeline to return to service, with the 737 MAX’s all-important certification flight expected to take place soon, Boeing officials insisted.

The aircraft has been grounded since last March following the second of two fatal crashes that killed a combined 346 people.

American Airlines, Southwest Airlines and United Airlines have each extended their 737 MAX cancellations into late-summer.

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