08/12/2013: C-17 at Joint Base Charleston [slidepress gallery='c-17-at-joint-base-charleston'] Credit:Joint Base Charleston Public Affairs Office:6/4/13 In the first two photos, Tech. Sgt. Andrew Gravett, 437th Aircraft Maintenance Squadron crew chief, walks along the top of a C-17 Globemaster III while wearing a safety harness as he does a routine maintenance check…