Type 636 is an advanced model of the Russian Kilo-class submarines. Credit: Christopher Michel.
The Type 636 submarine is fitted with six 533mm forward torpedo tubes. Credit: Urri / Shutterstock.
The submarines can achieve a speed of 20k when submerged. Credit: Urri / Shutterstock.

The Russian Kilo-class submarine first entered service in the early 1980s. It was designed by the Rubin Central Maritime Design Bureau in St Petersburg. Subsequent developments led to the improved production versions, including the Type 877EKM, Type 636, and Type 636.3. A successor, the Lada (Project 677), was launched in November 2004.

Rubin is developing an air-independent propulsion (AIP) system, which could be available for retrofit to the other versions. The Kilo submarine was originally built at the Komsomolsk shipyard but is now constructed at the Admiralty Shipyard in St Petersburg.

Type 636 is designed for anti-submarine warfare (ASW) and anti-surface-ship warfare (ASuW) and also for general reconnaissance and patrol missions.

The Type 636 submarine is considered to be one of the quietest diesel submarines in the world. It is capable of detecting an enemy submarine at a range three to four times greater than it can be detected itself.

SSK Kilo-class (Type 636) orders and deliveries

China has two Type 636 submarines, the second of which joined the Chinese fleet in January 1999. It also has eight Project 636M submarines.

In November 2007, Venezuela signed a memorandum of understanding (MoU) for three Type 636 submarines to be delivered from 2012 to 2013.

Vietnam ordered six Type 636 submarines in 2009 and all submarines were delivered between 2013 and 2017.

In January 2019, Algeria commissioned two Kilo-class Russian submarines at the Mers El Kébir naval base.

Type 636 submarine design

The submarine consists of six watertight compartments separated by transverse bulkheads in a pressurised double-hull. The design and the submarine’s optimal reserve buoyancy lead to increased survivability if the submarine is holed, even with one compartment and two adjacent ballast tanks flooded.

"The Russian Kilo-class submarine first entered service in the early 1980s."

The foreplanes are positioned on the upper hull in front of the fin or sail. The design is a development of the 877EKM Kilo-class with the extended hull. The power of the diesel generators was increased and the main propulsion shaft speed was reduced to provide a substantial reduction in the acoustic signature of the submarine.

Command system

The submarine is equipped with a multi-purpose combat and command system, which provides information for effective submarine control and torpedo firing.

The system’s high-speed computer can process information from the surveillance equipment and display it on the screen, determine submerged and surface target data and calculate firing parameters, provide automatic fire control, and provide information and recommendations on manoeuvres and deployment of weapons.


The submarine has a launcher for eight Strela-3 or Igla surface-to-air missiles. The missiles are manufactured by the Fakel Design Bureau, Kaliningrad. Strela-3 (Nato Designation SA-N-8 Gremlin) has a cooled infrared seeker and 2kg warhead. Maximum range is 6km.

Igla (Nato designation SA-N-10 Gimlet) is also infrared-guided but heavier with a maximum range of 5km and speed of Mach 1.65.

The vessels can be fitted with the Novator Club-S (SS-N-27) cruise missile system, which fires the 3M-54E1 anti-ship missile. The range is 220km with 450kg high-explosive warhead.


The submarine is equipped with six 533mm forward torpedo tubes situated in the nose of the submarine and carries 18 torpedoes with six in the torpedo tubes and 12 stored on the racks. Alternatively, the torpedo tubes can deploy 24 mines.

Two torpedo tubes are designed for firing remote-controlled torpedoes with very high accuracy. The computer-controlled torpedo system is provided with a quick-loading device. The first salvo is fired within two minutes and the second within five minutes.

Sensors on board SSK Kilo-class (Type 636) submarine

Type 636 is fitted with the MGK-400EM digital sonar. This provides detection of submarine and surface ship targets in sonar listening mode, echo-ranging in a ±30° sector of the target relative bearing, telephone and telegraph communication in both long and short-range modes, detection of underwater sound signals and determination of the signal bearing.

The submarine’s radar works in periscope and surface modes and provides information on the underwater and air situation, radar identification, and navigational safety.


Kilo-class countermeasures include electronic support measures (ESM), radar warning receiver, and direction finder.

Propulsion and performance

The submarine’s propulsion system consists of two diesel generators, the main propulsion motor, a fuel-economic motor, and a single shaft, driving a seven-blade fixed-pitch propeller.

There are two additional stand-by motors for running in shallow waters, at the mooring and in cases of emergency. Two 120-cell storage batteries are installed in the first and third compartments of the submarine. The main machinery is equipped with an automatic control system.

The vessel’s maximum diving depth is 300m while speed is 11k when surfaced and 20k when submerged. It can achieve a range of 7,500 miles when snorkelling at 7k and 400 miles when submerged at 3k.