U.S. Sailors aboard the guided missile destroyer USS Donald Cook (DDG 75) perform a foreign object damage walk down on the ship's flight deck before helicopter landing operations in the Black Sea April 11, 2014. The Donald Cook was on a scheduled patrol in the U.S. 6th Fleet area of operations in support of the European Phased Adaptive Approach. U.S. Navy guided missile destroyers operated in the Black Sea on a mission to train with partner nation navies and promote peace and stability in the region. (U.S. Navy photo by Mass Communication Specialist Seaman Edward Guttierrez III/Released)