The US Federal Aviation Administration (FAA) said that it had found another fault in undelivered Boeing 787 Dreamliner planes.
The aerospace giant will have to fix the issue before the jets can be delivered, it added.
According to the FAA, the issue poses no immediate threat to flight safety.
The issue in question is “near the nose on certain 787 Dreamliners in the company’s inventory of undelivered airplanes”, the agency said.
“This issue was discovered as part of the ongoing system-wide inspection of Boeing’s 787 shimming processes required by the FAA.”
The company has about 100 undelivered Dreamliners which will need fixing.
The fault, which was first reported by Reuters, is the latest setback for the planemaker in what has been a difficult few years.
The firm’s 737 Max and 787 have been afflicted by electrical and other issues since late last year, and it had only resumed deliveries of the 787s in March after a five-month hiatus – only to halt them again in May.
Prior to that, Boeing’s 737 Max model was grounded for 20 months after two fatal crashes killed 346 people in 2018 and 2019.
Boeing declined to comment.