A model of the MS 200 mini submarine. China has recently unveiled a new type model. Image: Twitter

China unveiled a new type of mini-submarine this month, one that is likely designed for shallow water operations and built for export.

From limited video footage of the sub, analysts estimate it is about 49 meters long, in comparison with China’s flagship 77.6 meter-long Type 039C Yuan class. 

The new mini-sub features a sleek sail reminiscent of the Type 212 and dive fins on the forward casing, as seen on the Type 214. China’s new midget sub is believed to be armed with four torpedo tubes without reloads. Overall, little else is known about this new sub. 

Significantly, China’s mini-subs are suited for operations in the Taiwan Strait, which has an average depth of 60 meters.

In the event of a Taiwan Strait conflict, mini-subs could act as advance parties to infiltrate Taiwan’s ports and naval bases, mine sea lanes of approaches, insert special operations teams, ambush Taiwanese naval forces and contribute to enforcing China’s blockade against Taiwan. 

In 2017, the China Shipbuilding Industry Corporation (CSIC) unveiled a family of mini-subs for export, including the MS 200, S600 and S1100. 

The MS 200 was the first special operations sub China unveiled to the public. It was designed for offshore operations in shallow waters, performing tasks such as reconnaissance, surveillance, special operations and patrols.

It has a 200-ton displacement, 30-meter length, 3.6-meter width and 4.4-meter height. It has a maximum speed of 8 knots, a submerged range of 120 nautical miles and a mixed range of 1,500 nautical miles.

The sub has an endurance of 15 days, with a crew of six sailors, eight special forces and an armament of two torpedo tubes. 

The substantially larger S600 has a 600-ton displacement, 50-meter length, 5.6-meter width and 5.6-meter height. It has a submerged maximum speed of 15 knots and 9 knots on the surface, a maximum range of 2,000 nautical miles and 400 nautical miles on its air-independent propulsion (AIP) module.

It has a maximum diving depth of 200 meters, an endurance of 20 days, houses a 15-person crew and is armed with four torpedo tubes. 

The even larger S1100 AIP mini-sub has a 1,100-ton displacement, 60-meter length, 5.6-meter width and has a 6.8-meter height. In terms of performance, it has a maximum submerged speed of 15 knots, a maximum range of 3,000 nautical miles and 800 nautical miles while submerged using its AIP module.

The bigger boat has a diving depth of 200 meters, a crew of 18 sailors and is armed with four torpedo tubes. 

For comparison, China’s Type 039A/B Yuan subs displace 2,725 tons surfaced, have a 77.6-meter length, an 8.4-meter width and can travel up to 20 knots while submerged.

These boats have a crew of 38 and are armed with six torpedo tubes capable of launching both torpedoes and anti-ship missiles. 

Mini-subs are substantially smaller than larger conventional boats, which limits their range, armaments and endurance. However, their small size and low cost make them suitable for shallow water operations, infiltration and naval asymmetric warfare.

China can also offer its new mini-sub for export to customers such as Thailand, whose naval operating environment favors the use of small, shallow-water submarines over large conventional boats.

The Gulf of Thailand is on average 45 meters deep, which raises operational suitability questions about Thailand’s plans to acquire two Yuan-class boats from China.  

Apart from China, North Korea and Iran have substantial mini-sub fleets, whose employment of such boats illustrates their doctrinal and operational benefits in a naval asymmetric warfare strategy. 

North Korea operates an estimated 40 Sang-O and Sang-O II mini-subs and approximately 20 Yugo and Yono class boats. These small craft are qualitatively no match for South Korea’s far superior naval forces, but they fit perfectly into North Korea’s asymmetric defense strategy.

Notably, one of these mini-subs was thought to be responsible for the 2010 sinking of the ROKS Cheonan. North Korea has also used its mini-subs to infiltrate its special forces into South Korea on multiple occasions, notably in 1996 and 1998.

Iran fields approximately 31 mini-subs of various types, such as the Besat, Fateh, Nahang, Ghadir and Yugo classes. Iran’s mini-subs are suited to the confined and shallow waters of the Persian Gulf, which offsets their limited range and armaments.

As with North Korea, Iran uses its mini-subs to offset its naval weakness against the US Navy in the Persian Gulf. These boats also are a key tool for Iran’s strategy to threaten oil shipping in the Persian Gulf, which may buy it diplomatic leverage against the US and its Middle Eastern allies.