Turkey's STM Reveals Design of 540-ton Mini Attack Submarine

Turkey’s defense firm STM revealed a conceptual design of STM500, a 540-ton mini attack submarine, in a document it released recently.

When built, STM500 will be the smallest submarine built by Turkey. The other submarines used by the Turkish Navy have a displacement of 1100-1600 tons. Reis class submarines, which are still in production, are expected to have a displacement of over 2000 tons in submerged condition.

According to defenceturk.net, the 42 metre-long STM500 will be a diesel-electric submarine developed for shallow waters.

The Qataris are currently getting the Italians to build mini-submarines for the Persian Gulf. The French are also studying a project which involves building such submarines.

Aside of being cost-effective owing to its size and quietness, such submarines are suitable for infiltration operations. “It is very difficult for any warship to perform underwater scanning with hull-mounted or towed sonar, especially in shallow waters and offshore areas with islets. The feature of this submarine is that it can operate extremely comfortably in the seas in question with its small dimensions,” the report noted.

STM500 can accommodate 18 crew members.  It can operate at depths of more than 250 meters for 30 days with a 6-person Special Forces team. It is capable is speeds of around 18 knots.

The vessel is powered by two diesel generators and Lithium-Ion batteries. Air Independent Propulsion system is optional.

STM500 is suitable for surveillance, reconnaissance and mine warfare operations.

The attack submarine is equipped with Battle Management System, Navigation Radar, Optronic Navigation and Assault Periscopes, Torpedo Countermeasure- Deceivers, Electronic Support Measures (ESM), Floating Antenna (BWA) and Sonars: CAS, CTA, PRS, MAS, IDRS, ONA. It has a total of 8 heavy torpedo and guided missile firepower with 4 ready-to-fire torpedo tubes.