180206-N-ZU710-027 Atlantic Ocean (Feb. 6, 2018) Fire Controlman 1st Class Christa Williams performs maintenance on a MK 15 Phalanx close-in weapons system (CWIS) following a live-fire exercise aboard the Arleigh Burke-class guided-missile destroyer USS Winston S. Churchill (DDG 81). USS Winston S. Churchill is underway as part of the Harry S. Truman Carrier Strike Group (HSTCSG) Composite Training Unit Exercise (COMPTUEX), which evaluates the strike group's ability as a whole to carry out sustained combat operations from the sea, ultimately certifying the HSTCSG for deployment. (U.S. Navy photo by Mass Communication Specialist 3rd Class Michael Chen/Released)