Kilo II-class Hunter-Killer Submarine

The Project 636 Varshavyanka-class submarine (NATO reporting name Kilo-II) is an improved version of the Kilo I-class submarine. Project 636 boats are equipped with improved MGK-400EM, with MG-519 Arfa also upgraded to MG-519EM. The improved sonar systems have reduced the number of operators needed by sharing the same console via automation. Algeria, the People's Republic of China, Russia and Vietnam all operate the Kilo II-class. Prospective users include Indonesia (two subs), the Philippines (three subs) and Venezuela (three subs).

Algerian Navy

 * Messali el Hadj (021)
 * Akram Pacha (022)

People's Liberation Army Navy

 * Yuan Zheng 66 Hao (366)
 * Yuan Zheng 67 Hao (367)
 * Yuan Zheng 68 Hao (368)
 * Yuan Zheng 69 Hao (369)
 * Yuan Zheng 70 Hao (370)
 * Yuan Zheng 71 Hao (371)
 * Yuan Zheng 72 Hao (372)
 * Yuan Zheng 73 Hao (373)
 * Yuan Zheng 74 Hao (374)
 * Yuan Zheng 75 Hao (375)

Russian Navy

 * RFK Novorossiysk (B-261)
 * RFK Rostov-on-Don (B-237)
 * RFK Stary Oskol (B-262)
 * RFK Krasnodar (B-265)
 * RFK Veliky Novgorod (B-268)
 * RFK Kolpino (B-271)
 * RFK Volkhov - planned for construction
 * RFK Mozhaisk - planned for construction
 * RFK Petropavlovsk-Kamchatsky - planned for construction

Vietnam People's Navy

 * Hà Nội (HQ-182)
 * Hồ Chí Minh City (HQ-183)
 * Hải Phòng (HQ-184)
 * Khánh Hoà (HQ-185)
 * Đà Nẵng (HQ-186)
 * Bà Rịa-Vũng Tàu (HQ-187)