180417-N-XK398-107 PHILIPPINE SEA (April 17, 2018) Marines assigned to the 31st Marine Expeditionary Unit (31st MEU) wait in an amphibious assault vehicle in the well deck of the amphibious dock landing ship USS Ashland (LSD 48) after completing a mechanized raid as part of a certification exercise (CERTEX). CERTEX is the final evaluation in a series of training exercises which ensures readiness for crisis response throughout the Indo-Pacific region. (U.S. Navy photo by Mass Communication Specialist 3rd Class Joshua Mortensen/Released)