Last year, the F.A.A. said it was also investigating claims by a Boeing engineer that parts of the fuselage, or body, of the Dreamliner were improperly fastened together, which the whistle-blower said could cause premature damage to the plane over years of use.

Boeing has called the 787 Dreamliner its "best selling passenger planes" as it offers spacious cabins and large windows. However, multiple safety concerns have been raised in recent years.