WASHINGTON (AP) — The Air Force said Friday it has ordered immediate inspections and repairs to about 130 of its A-10 aircraft to fix possible cracks in the wings.

There has been an increase in the number of cracks found in the thin-skin wings, largely related to fatigue in the aging fleet, the service said in a statement. The A-10 Thunderbolt II is the workhorse in the fleet of planes used by the Air Force for close-air support on the battlefront.

The wings were installed during the original manufacture, the Air Force said, adding that the inspections involve aircraft assigned around the world, including to the Air National Guard, Air Combat Command and the Pacific Air Forces.

Priority is being give to the aircraft currently in the U.S. Central Command area of responsibility, which includes Iraq and Afghanistan. The Air Force said the inspections will not affect current or future combat missions.