Airmen from the 155th Air Refueling Wing perform depaneling on a KC-135R Stratotanker’s with the 126th Air Refueling Wing on Dec. 1, 2022, during a isochronal inspection at Scott Air Force Base, Ill. An ISO is an in-depth inspection of every component of the airframe accomplished by maintenance every 30 months, 1800 flight hours, or 1000 landings to meet mission requirements. (U.S. Air National Guard courtesy photo by Chief Master Sgt. Greg Malina)