Japan's Maritime Self-Defense Force (MSDF) vessels sail during a fleet review off Sagami Bay, Kanagawa prefecture, on Oct. 18, 2015. (Xinhua/Ma Ping)

Photo taken on on Oct. 18, 2015 shows Japan's Maritime Self-Defense Force (MSDF) aeroplanes during a fleet review off Sagami Bay, Kanagawa prefecture. (Xinhua/Ma Ping)

Japan's Maritime Self-Defense Force (MSDF) ship sails during a fleet review off Sagami Bay, Kanagawa prefecture, on Oct. 18, 2015. (Xinhua/Ma Ping)

Japan's Maritime Self-Defense Force (MSDF) ships sail during a fleet review off Sagami Bay, Kanagawa prefecture, on Oct. 18, 2015. (Xinhua/Ma Ping)

Photo taken on on Oct. 18, 2015 shows Japan's Maritime Self-Defense Force (MSDF) aeroplanes during a fleet review off Sagami Bay, Kanagawa prefecture. (Xinhua/Ma Ping)