U.S. Air Force Staff Sgt. Carl Petmecky and Senior Airman Alexander Reyes, 67th Aircraft Maintenance Unit crew chiefs, push their tool cart off the flightline during a shift change Oct. 21, 2016, at Kadena Air Base, Japan. Petmecky and Reyes performed maintenance on an F-15 Eagle, an operation that utilizes 24-hour manning to ensure constant mission readiness should the call of duty arise to defend Okinawa and other U.S. interests in the Indo-Asia Pacific region. (U.S. Air Force photo by Senior Airman Peter Reft/Released)