Maintenance Squadron gets new commander Published May 7, 2012 DOVER AIR FORCE BASE, Del. -- The 512th Maintenance Group Commander Col. Kelvin D. McElroy (left) presents the 512th Maintenance Squadron guide-on to Lt. Col. James Hartle, the new commander of the 512th MXS, during a ceremony May 5, 2012, in Bldg. 725, Dover Air Force Base, Del. Hartle previously served as the 512th Maintenance Operations Flight commander.