Petty Officer 2nd Class Keith Bryan, a machinery technician in the Coast Guard Cutter Polar Star's main propulsion division, explains simulation procedures before engineering casualty exercises while underway in the Ross Sea, near Antarctica, Feb. 4, 2016. Bryan and other evaluators observed as the cutter’s engineering watchstanders responded to simulated damage to the ship’s machinery. (U.S. Coast Guard photo by Petty Officer 2nd Class Grant DeVuyst)