Boeing on Tuesday warned about a new defect on its 787 Dreamliner planes and that it will delay deliveries of the wide-body aircraft, the manufacturer’s latest production issue.

“We are inspecting 787s in our inventory for a nonconforming condition related to a fitting on the horizontal stabilizer,” Boeing said in a statement. “Airplanes found to have a nonconforming condition will be reworked prior to ticket and delivery.”

Boeing said the issue isn’t related to flight safety and that planes in service can continue operating.

The problem is the latest in a spate of manufacturing issues on Boeing planes that have slowed if not paused deliveries of certain aircraft outright, just as airlines are clamoring for new planes to capitalize on the travel boom.

Boeing had paused deliveries of the planes for several weeks earlier this year because of a separate problem on a fuselage component on certain 787s. The latest issue currently doesn’t affect Boeing’s full-year outlook for Dreamliner deliveries, the company said. Boeing has estimated that it would deliver between 70 and 80 of the planes this year.

The company has also had to rework some of its bestselling 737 Max planes this year because of an issues with fittings in some planes’ aft fuselages, made by Spirit Aerosystems.

Boeing shares fell sharply on the news but largely recovered, and were recently down less than 1% in afternoon trading.