Boeing Expands Search for Structural Defects on 787 Dreamliners

Boeing Co. has widened its inspections of newly built 787 Dreamliner planes to hunt for additional manufacturing defects that could prematurely age the jets’ carbon-fiber frames.

While U.S. regulators say the faults don’t pose an immediate hazard, the emergence of another flaw in Boeing’s most advanced jetliner is slowing deliveries and raising doubts about quality controls. The company didn’t deliver any 787 jets in November, Chief Financial Officer Greg Smith said earlier this month, citing inspections that took longer than expected.

The latest issue involves tiny variances, or wrinkles, in the interior lining where composite fuselage barrels are linked to ...