OVERVIEW: The SS 573 *Yushio* is a *Yushio*-class diesel-electric attack submarine (SSK) operated by the Japan Maritime Self-Defense Force (JMSDF).

DETAILS: The *Yushio* class was developed in the late 1970s and 1980s as a follow-on to the *Uzushio* class, incorporating significant improvements in acoustic stealth and sensor technology. Design priorities focused on enhanced anti-submarine warfare (ASW) capabilities within the restrictive operating environment of the Japanese archipelago, particularly in the shallow waters and complex littoral regions around Japan. The class represented a crucial step in the JMSDF's modernization efforts, seeking to maintain a technologically advanced and highly capable submarine force despite the limitations imposed by Japan's pacifist constitution on offensive military capabilities. The adoption of advanced noise reduction techniques and domestically produced sonar systems was key to the class's improved performance relative to its predecessors.

The *Yushio* class submarines primarily fulfill anti-submarine warfare (ASW) and anti-surface warfare (ASuW) roles, providing a crucial layer of defense against potential threats to Japanese territorial waters and sea lanes. The *Yushio* can also conduct intelligence, surveillance, and reconnaissance (ISR) missions. While not specifically designed for anti-air warfare (AAW), the submarine’s sensors and communications suite enable it to contribute to maritime domain awareness and report potential aerial threats to higher command authorities. Its operational profile emphasizes patrol duties within the Sea of Japan, the East China Sea, and the surrounding Pacific regions.

The *Yushio*'s sensor suite is built around the J/ZQQ-5B bow sonar, providing long-range detection and tracking of submerged contacts. This sonar system, indigenous to Japan, is integrated with the AN/BQR-15A towed array sonar, further enhancing its ASW capabilities, particularly in detecting quiet submarines at longer ranges. The J/ZPS-6 surface search radar provides situational awareness above the waves. Electronic warfare support is provided by the J/ZLR-3 radar warning receiver and a generic acoustic intercept system, enabling the *Yushio* to detect and analyze enemy radar and sonar emissions. The boat is equipped with both optical and low-light television (LLTV) periscopes, enhancing its surveillance capabilities in both day and night conditions. The submarine's 533mm torpedo tubes allow for engagement of both submarine and surface targets.

SPECIFICATION: Length: 72.0 m || Beam: 9.9 m || Draft: 7.5 m || Disp: 1850 t

SENSORS: AN/BQR-15A || J/ZQQ-5B Bow || J/ZPS-6 || J/ZLR-3 || Generic Acoustic Intercept || Generic Submarine Periscope, Optical || Generic Submarine Periscope, LLTV

ARMAMENT: 533mm TT || Signal Ejector