U.S. Marines brace themselves against the blast of rotor wash from an MH-53 Sea Stallion helicopter during flight operations on the amphibious assault ship USS Boxer (LHD 4) as the ship operates in the Pacific Ocean on July 10, 2013. The Boxer is underway off the coast of Southern California to conduct a composite training unit exercise aimed at integrating the ships of the Boxer Amphibious Ready Group through a series of live training events.