U.S. top aircraft manufacturer Boeing Company Sunday confirmed that some 737 aircraft involving MAX and NG models may have risks from faulty parts that would result in "a potential nonconformance."
Boeing said one batch of slat tracks with specific lot numbers produced by a supplier was found to be improperly manufactured.
At least 21 737 NGs and 20 737 MAX airplanes have been identified to be most likely to have the parts in question, said Boeing, which noted that it has not received any in-service issues related to this batch of slat tracks.
Slat tracks are used to guide movable panels called slats located on the front edge of an airplane's wings to provide additional lift during takeoffs and landings.
Boeing said it is cooperating with the U.S. Federal Aviation Administration (FAA) on fixing the newly-found problem while contacting 737 operators, advising them to inspect the slat track assemblies on certain airplanes.
The company suggested inspections be conducted on an additional 112 NG and 159 MAX models, saying one or two days would be required for the replacement work if necessary.
A separate service bulletin will be issued for 737 MAX operators to do inspections before the MAX fleet returns to service, Boeing said.
Boeing 737 MAX aircraft have been grounded globally since March this year after two of the planes crashed in two fatal accidents that killed 346 people in Ethiopia and Indonesia in nearly six months.
Boeing has since been under close examination about its flight safety, and pressured to upgrade the software of a flight control system. It has not submitted the software upgrade to the FAA for approval.
