American Airlines Grounds 14 Planes in One Day, After Complaints Some Overhead Bins Aren’t Closing Properly

American Airlines said it was grounding 14 of its planes Thursday as it investigates pilot complaints that some of the new overhead bins installed in recently upgraded airplanes weren’t closing properly.

American said that the pilots complained about the overhead bins in two of the 14 Boeing 737-800 aircraft that recently had been upgraded by a vendor licensed by the Federal Aviation Administration. Reuters identified the vendor as ATS, a longtime American supplier.

“After further inspection by American, the work that was conducted on these two aircraft was not up to our standards,” American said in a statement to Fortune. “Out of an abundance of caution, we have proactively removed from service the additional 12 aircraft that were updated by this vendor and have notified the FAA. We will perform additional inspection work on these 14 aircraft.”

American maintained that the overhead-bin issue didn’t affect the safety of its flights, but said it’s working with the FAA to address the issue. The airlines’ other 290 Boeing 737-800 planes weren’t affected. The company said that it rebooked all customers affected by the 40 flights cancelled by the grounded aircraft. “We never want to disrupt our customers’ travel plans, and we are sorry for the trouble this has caused,” American said.

American Airlines’ stock fell 54 cents a share, or 1.7%, to $32.22 a share Thursday.