437th Airlift Wing maintainers perform routine maintenance and system checks on a C-17 Globemaster III June 25, 2014, at Joint Base Charleston, South Carolina. The maintainers perform checks and maintenance around the clock to ensure the aircraft are ready to fly. (U.S. Air Force photo/Senior Airman Dennis Sloan)

437th Airlift Wing maintainers perform routine maintenance and system checks on a C-17 Globemaster III June 25, 2014, at Joint Base Charleston, South Carolina. The maintainers perform checks and maintenance around the clock to ensure the aircraft are ready to fly. (U.S. Air Force photo/Airman 1st Class Clayton Cupit)

A 437th Airlift Wing maintainer performs routine maintenance and system checks on a C-17 Globemaster III June 25, 2014, at Joint Base Charleston, South Carolina. The maintainers perform checks and maintenance around the clock to ensure the aircraft are ready to fly. (U.S. Air Force photo/Airman 1st Class Clayton Cupit)