Yugo-class submarine

Class overview
Name	Yugo class
Builders	Yukdaeso-ri shipyard
Operators	Democratic People's Republic of Korea (former) Iran (current) Vietnam (current, to be decommissioned in 2012)
Succeeded by	Sang-O class
In commission	Late 1960s
Completed	8
Active	6
Lost	1
Retired	1
Preserved	none
General characteristics
Type	midget submarine
Displacement	90 up to 110 tons (submerged)
Length	20m
Beam	2m
Propulsion	Single-shaft MTU diesel engine
Speed	10 knots (19 km/h) surfaced 4 knots (7.4 km/h) submerged
Range	Unable to reach the southern extreme of South Korea
Capacity	4-6 Special forces troops
Armament	Some armed with two 21-inch (530 mm) torpedoes, possibly in drop collars.
Notes	First successful indigenous midget submarine

The Yugo class submarine is a class of four midget submarines used primarily for infiltration and espionage by North Korea. The class is so named because it was built to plans supplied to North Korea by Yugoslavia in 1965. This class is actually a family of midget submarines for that not all are identical. The displacement is either the standard 90 tons of the original Yugoslavian design for the early units, or 110 tons for the later units, while armament is either a pair of 400 mm torpedo tubes (early units) or a pair of 21 in short torpedo tubes (later units); however, all units have the same range: 550 nautical miles (1,020 km) at 10 knots (19 km/h) on the surface and 50 nautical miles (93 km) at 4 knots (7.4 km/h) submerged. Their final example was built in the 1980s, after which they were superseded by the Sang-O class submersibles. In 1998 one out of the 6 submarines was captured by the South Koreans. In July 2007, 4 were given to Iran to repay some of North Korea's debts to Iran, the last one was retired but kept by the North Koreans.