|Builders:||North Korean Navy Yukdaeso-ri Naval Shipyards|
|Preceded by:||Yugo class|
|Active:||<36 (most in reserve)|
|Length:||20–22 m (65 ft 7 in–72 ft 2 in)|
|Beam:||2.75 m (9 ft 0 in)|
|Draught:||1.6 m (5 ft 3 in)|
|Propulsion:||Single-shaft MTU diesel engine with electric drive|
|Complement:||2 + 6 or 7 special forces personnel|
The Yono-class submarine (also as Yugo class) is a class of North Korean miniature submarines, produced for domestic use as well as for export. Also referred to as the Yeono class, these submarines displace 130 tons, significantly less than North Korea's larger 1,800-ton Romeo-class submarines. As of May 2010, North Korea is reported to operate ten of these submarines.
A Yono-class submarine is thought to have fired the torpedo attack which sank a South Korean Pohang-class corvette, ROKS Cheonan on 26 March 2010 in South Korean waters. According to some investigators, the weapon used in the attack was a North Korean-manufactured CHT-02D torpedo, from which substantial propulsion parts were recovered. The device allegedly exploded not by contact, but by proximity 6 to 9 metres (20 to 30 ft) below Cheonan, creating a powerful pillar of water, called the bubble jet effect.
High ranking North Korean military officials denounced the international investigation and said the North does not have the type of submarines that supposedly carried out the attack. They also dismissed claims regarding writings on the torpedo and clarified that "when we put serial numbers on weapons, we engrave them with machines." South Korea's Yonhap News quoted South Korean officials as saying the North has about ten of the Yeono-class submarines.
A member of the North Korean cabinet who defected to South Korea in 2011, said on 7 December 2012 that the crew of the North Korean submarine which sank Cheonan had been honored by the North Korean military and government. The defector, known by the alias "Ahn Cheol-nam", stated that the captain, co-captain, engineer, and boatswain of the mini-sub which sank Cheonan had been awarded "Hero of the DPRK" in October 2010.
Export and foreign production
The US Congressional Research Service suggests that Iran has purchased several midget submarines from North Korea. The purchase may have involved Yono and Yugo-class mini-subs. Beginning in 2006, Iran launched the first of several domestically-produced mini-submarines.
In 2007 the Iranian navy unveiled its Ghadir-class submarine, the first of a number of planned midget submarines of the Yono class. Observers[who?] have disagreed on the exact classification of the Iranian derivative: Iran claims the vessel is a fully independent design, but it has been compared to the North Korean Yugo boats, Yono subs, and/or Sang-O-class coastal submarines.
- North Korea rebuffs South Korea's evidence on Cheonan attack, Christian Science Monitor, 20 May 2010.
- "S Korea Confirms North's Torpedo Sank Warship". Malaysian National News agency. 21 May 2010. Retrieved 21 May 2010.
- "North Korea condemned by world powers over torpedo attack". The Telegraph. 20 May 2010. Retrieved 20 May 2010.
- South Korea Faces Domestic Skeptics Over Evidence Against North, by Ben Richardson and Saeromi Shin, Bloomberg News, 30 May 2010
- JoongAng Ilbo, "N. Korean Sailors Awarded Hero's Title For Attack On S. Korean Warship: Defector", 8 December 2012
- Iran Buys North Korean Midget Submarines Archived 14 July 2011 at the Wayback Machine, Marport: Happenings From the World of Deep Sea Technology
- The Naval Institute Guide to Combat Fleets of the World: Their Ships