SEATTLE, Wash. (AP) — Inspections of some older Boeing jets have turned up structural cracks in more than three dozen planes.

That’s raising a new safety issue for the company, which is already dealing with two deadly crashes involving a newer version of the same plane.

Boeing said Thursday that airlines worldwide have inspected 810 Boeing 737 NG planes following an order from U.S. safety regulators, and 38 had “findings” that will require repairs.

Airlines are now under orders to inspect certain 737 NGs for cracking in a part that helps keep wings attached to the fuselage.