U.S. Marines participate in a ‘Murph’ workout challenge in memory of Gunnery Sgt. Diego Pongo and Capt. Moises Navas aboard amphibious assault ship USS America (LHA 6). . - U.S. Marines participate in a ‘Murph’ workout challenge in memory of Gunnery Sgt. Diego Pongo and Capt. Moises Navas aboard amphibious assault ship USS America (LHA 6). .