By Kimberley Kao

Boeing is investigating a quality problem with its undelivered 787 Dreamliner planes after discovering that some fasteners were incorrectly installed on the jets' bodies, adding to the aircraft maker's woes amid heightened scrutiny from U.S. regulators.

The issue involves incorrect torquing, or tightening, of some fasteners in the "side-of-body area" of some planes, which was discovered as part of Boeing's regular quality checks, the aircraft maker said Friday.

Boeing said it is "taking the time necessary to ensure all airplanes meet our delivery standards prior to delivery," adding that the "in-service fleet can continue to safely operate."

The U.S. Federal Aviation Administration has already undertaken multiple investigations into Boeing's safety standards, including the midair blowout of a door plug on an Alaska Air flight in January. The U.S. Justice Department opened a criminal investigation into that incident.

In a separate statement, the FAA said Boeing disclosed that it may have "improperly installed fuselage fasteners" on some 787 Dreamliner airplanes. "The FAA is investigating and is working closely with Boeing to determine appropriate actions and to ensure an immediate fix in the production system," it said Friday.

Boeing said its evaluation is ongoing to determine whether the planes would need changes if any, and that there might be little to no impact on delivery timelines. Deliveries of new 787 jets aren't suspended, it said.

In his testimony to the U.S. Senate Committee on Commerce, Science, and Transportation on Thursday, FAA chief Mike Whitaker said his administration would continue to ensure Boeing makes sustained changes to its quality assurance and production.

Increased auditing of quality systems "with more active, in-person oversight" would help the FAA increase visibility on operations at all original equipment manufacturers for aircraft, including Boeing, Whitaker said.

Write to Kimberley Kao at

(END) Dow Jones Newswires

06-14-24 0348ET