Seaman Apprentice Brian Musgrave comes up for air while swimming back to the beach during his final basic crewman training evolution at Naval Amphibious Base Coronado. The final training evolution, known as the "Tour," is a three-day, two-night training session in which the students are tested physically and mentally on what they have learned during the seven-week program. BCT is the first phase of special warfare combatant-craft crewman training. SWCCs operate and maintain the Navy's inventory of state-of-the-art, high performance boats used to support SEALs in special operations missions worldwide.