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Sang-O (class)

Diesel-Electric Attack Submarine / Coastal Patrol Submarine

The Sang-O class of diesel-electric attack submarines powers a bulk of the North Korean Navy underwater force.
Authored By: Staff Writer | Edited: 8/9/2017
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Year: 1991
Ships-in-Class: 42
Named Ships: At least 40 ships believed to have been constructed since 1991.
Roles: Hunter; Direct-Attack; Special Forces Support;
Complement: 15
Length: 111.5 ft (33.99 m)
Width: 12.45 ft (3.79 m)
Displacement (Surface): 275 tons
Displacement (Submerged): 370 tons
Propulsion: 1 x Diesel-electric unit driving power to 1 x Shaft.
Speed (Surface): 7.5 kts (9 mph)
Speed (Submerged): 9 kts (10 mph)
Range: 1,512 nm (1,740 miles; 2,800 km)
Operators: North Korea
The Sang-O-class of attack submarine makes up the largest underwater component of the modern North Korean Navy as at least forty of the type are believed to have been constructed. The first examples were unveiled in 1991 and many remain in active service today (2016). The submarine group offers basic attack, reconnaissance and mine-laying capabilities though lack an inherent missile-firing functionality and all are diesel-electric-powered boats cleared for cruising near the North Korean coastline (as opposed to deep water operation).

A typical Sang-O crew complement numbers just fifteen men, showcasing its very modest, compact dimensions which include a running length of 34 meters and a beam of 3.8 meters. Displacement is 275 tons when surfaced and 370 tons when submerged. Range is out to 1,500 nautical miles with depths tested down to 150 meters. Reported speed values include a surfaced speed of 7.5 knots and a submerged speed of 9 knots - making the Sang-O not particularly fast in any way. Typical radar and sonar sets are fitted to the bulk of the Sang-O group which provide basic underwater naval functionality. Standard armament is a simple pairing of 533mm bow-facing torpedo tubes firing the Russian-originated 53-65KE torpedo. The overall design shape of the Sang-O is typical of compact attack submarines - a rounded bow, mid-set sail and tapered stern section. Dive planes are featured well-forward and low along the bow.

It is largely assumed that, despite the size of the North Korean Navy's submarine force (second only to the United States on paper), the underwater fleet is largely outclassed by more modern submarine fleets seen globally. However, the force still supplies some tactical and strategic value as it can be used in a harassment and deterrent measure when pressed while also posing a viable threat to South Korean surface ships (both commercial and military in nature).

There is also an improved version of the Sang-O-class as the "Sang-O II" (also "K-300"), its existence first reported in 2011. These boats are slightly larger in dimension and heavier in displacement, adding to increased operational ranges and more internal volume for stores and special mission equipment. Its propulsion system not entirely known as it could be carried over from the earlier Sang-O design or of an all-new local endeavor.

The Sang-O stands as the largest locally-constructed submarine group available to the North Korean Navy. One example was captured by the South Korean Navy on September 18th, 1996 when it ran aground while spying near Gangneung. The vessel landed three special operations personnel and ran aground during the extraction phase of the mission. During the ensuing operation to collect the enemy forces (who had abandoned their submarine), twelve South Koreans were killed and twenty-four North Koreans perished. One was captured alive along with the abandoned submarine.


2 x 533mm torpedo tubes (53-65KE torpedoes)

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