Staff Sgts. Dequan McHatten, left, and Justin Miller, 62nd Aircraft Maintenance Squadron crew chiefs, maneuver a new tire toward a C-17 Globemaster III Jan. 17, 2012, at Joint Base Lewis-McChord, Wash. Part of a crew chief’s responsibilities include maintaining, servicing and inspecting aircraft and aerospace support equipment as well as using technical data to diagnose and solve maintenance problems on aircraft systems. (U.S. Air Force photo/Airman 1st Class Leah Young)