150406-N-JN664-093 ATLANTIC OCEAN (April 6, 2015) USS Donald Cook (DDG 75) concludes flight operations with a Sikorsky S-61helicopter as part of Flag Officer Sea Training (FOST), April 6, 2015. Donald Cook, an Arleigh Burke-class guided-missile destroyer forward-deployed to Rota, Spain, is conducting naval operations in the U.S. 6th Fleet area of operations in support of U.S. national security interests in Europe. (U.S. Navy photo by Mass Communication Specialist 2nd Class Karolina A. Oseguera/Released)