180721-N-NH199-0014 SAN DIEGO (July 21, 2018) Sailors assigned to the Military Sealift Command hospital ship USNS Mercy (T-AH 19), man the rails as the ship arrives at Naval Base San Diego after deploying in support of Pacific Partnership 2018 and participating in the 2018 Rim of the Pacific exercise. Mercy provides emergency, on-site care for U.S. combatant forces deployed in war and other operations. The hospital ship’s secondary mission is to provide full hospital services to support U.S. disaster relief and humanitarian operations worldwide. Twenty-five nations, 46 ships, five submarines, about 200 aircraft, and 25,000 personnel are participating in RIMPAC from June 27 to Aug. 2 in and around the Hawaiian Islands and Southern California. The world’s largest international maritime exercise, RIMPAC provides a unique training opportunity while fostering and sustaining cooperative relationships among participants critical to ensuring the safety of sea lanes and security of the world’s oceans. RIMPAC 2018 is the 26th exercise in the series that began in 1971. (U.S. Navy photo by Mass Communication Specialist Seaman Harley K. Sarmiento/Released)