A 437th Aircraft Maintenance Squadron crew chief uses a marshaling glow stick to signal clearance of the left wing of a C-17 Globemaster III as it is towed into place to be chained down June 6, 2013, at Joint Base Charleston – Air Base, S.C. The C-17 was chained to the ground due to approaching tropical storm Andrea. (U.S. Air Force photo/ Senior Airman Dennis Sloan)