HILL AIR FORCE BASE, Utah (AP) — The U.S. Air Force has completed installing new wings on 173 A-10 attack jets to lengthen the service lives of the decades-old jets whose main mission is close support of ground forces.

The Standard-Examiner reported that Ogden Air Logistics Complex personnel at Hill Air Force Base in northern Utah swapped out the wings on 162 A-10s, with the remainder installed at Osan Air Base in South Korea.

The rewinging project to replace wings that outlived their lifespans started in 2011 and included using A-10 parts provided by an aircraft storage facility at Davis-Monthan Air Force Base in Tucson, Arizona.

A-10s started entering operational service in the late 1970s.