So I started looking into a North Korean v South Korea scenario in June 1985 and ran down the rabbit hole of North Korean Amphibious Forces.
Known ships/craft put together from looking at old declassified CIA reports:
"Construction and Modification of North Korean Naval Combatants January 1983 through July 1986"
"NORTH KOREAN NAVAL SHIPBUILDING, JULY 1980 - AUGUST 1982"
"NORTH KOREAN MILITARY CAPABILITIES AND INTENTIONS TOWARD SOUTH KOREA" - May 1975
declassified Marine Corps Books:
MCIA-2630-NK-016-97 - NORTH KOREA COUNTRY HANDBOOK - May 1997
US Army Books:
ATP 7-100.2, North Korean Tactics; July 2020
and Wikipedia:
(
https://en.wikipedia.org/wiki/List_o...eople%27s_Navy)
and CSIS
https://beyondparallel.csis.org/nort...-bases-part-1/
https://beyondparallel.csis.org/nort...bases-part-ii/
https://beyondparallel.csis.org/nort...ases-part-iii/
https://beyondparallel.csis.org/nort...bases-part-iv/
H.I. Sutton's Covert Shores:
http://www.hisutton.com/Demystified%...n%20craft.html
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Midget Submarines (SSM)
Basically assume that from 1975-1992 that a North Korean Midget Sub can deploy a squad (up to 8 men) of troops along the coastline. From 1992 onwards, larger Midgets may be capable of deploying two squads (14 men) along the coastline.
34 meter "Sang-O" (Shark) SSM - The first unit was observed under construction in the late 1980s on satellite intelligence, and construction of the first unit was completed in 1991. As of 2021, forty (40) are in service. Displaces 370 tons submerged. This class was made infamous when one ran aground in the 1996 Gangneung submarine infiltration incident; when after deploying a three man special operations recon team in South Korea -- it ran aground.
1 x
32 meter SSM -- first observed around 1984. First North Korean Midget with external torpedo tubes. Resembles WWII German UCIII U-Boat.
37 x 18/21 meter "Yugo" SSMs -- only six 21 meter (110 ton) SSMs have been seen. The rest (31) are the 18 meter (90 ton) version. They have been under construction since the 1970s; apparently based off the six 16 meter SSMs imported from Yugoslavia in 1973-74.
By mid-1983 they had 19 of these in the inventory; indicating a production rate of 4 a year. In 1984, the North Koreans tripled this rate to 12 a year. Both variants have a range of 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. They can carry about 4 to 6 special forces troops.
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Special Warfare Support Craft/Agent Boats (LCW)
The early versions of these craft from the 1950s to the 1970s were simply fast launches disguised as fishing boats, but by the 1980s, they had semi-submersible craft. By the 1990s, they were fully submersible, but couldn't run underwater; the submersible mode being used for evasion, waiting for someone, or caching them. By the 2000s, they could move underwater via electric motors. They can insert as before about 4 or so special forces troops.
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Amphibious Doctrine
The North Koreans began to construct a amphibious landing and fire support capability starting in 1971; aimed not at recreating Inchon, but rather, the capability to complicate South Korea's defensive positions by placing infiltrators rapidly along the coasts:
Per the USMC Intelligence Activity in 1997:
"Amphibious assaults against CFC [South Korea] probably would be small, clandestine landings involving two to six NAMPO craft; CHAHO or other naval craft could provide fire support."
Per the US Army in ATP 7-100.2, North Korean Tactics; July 2020:
"The two navy sniper brigades, one stationed on each coast, possess about 3,000 combat troops apiece.
These units have been placed under the operational control of the KPAN in order to enable amphibious operations. Construction of hovercraft bases for the brigades was previously observed at Sasulpo on the west coast and Tapchonri on the east coast, but these areas were later repurposed. The new west-coast hovercraft base will most likely be located at Yongbong-ni, and it is unknown where the east-coast hovercrafts will be based. The navy sniper brigades’ missions are similar to those of the KPAGF brigades, but the navy snipers will most likely land on the South Korean coastline. North Korea fields numerous types of landing craft, and it is estimated the KPA could deliver 5,000 to 7,000 personnel in one lift targeting both coastlines. Navy sniper brigade team missions would include:
Supporting a KPA ground offensive by securing river-crossing sites.
Conducting amphibious raids to destroy critical coastal targets in the enemy’s rear area.
Harassing enemy rear area logistical operations.
Attacking or destroying the enemy’s combat service support units.
Attempting to delay the movement of enemy reinforcements forward to the main combat area.
Attacking or destroying enemy airbases or naval facilities.
Occupying or raiding critical coastal islands.
Attacking enemy C2 and communications nodes.
Should hostilities erupt on the peninsula, a standing mission for KPAN sniper units is the capture of the five northernmost South Korean islands along the Northern Limit Line in the Yellow Sea, called the West Sea by South Korea."
Northern Limit Line Islands
...
"The KPAN fields three amphibious light infantry brigades, totaling 13 battalions. The primary differences from regular light infantry brigades are that these units routinely operate using naval landing craft and continuously practice amphibious landings on various types of beaches. One defecting navy sniper in 2011 boasted he traveled more than 32,000 km by sea on floating tubes during his training. These units train on a variety of landing craft, from the 350-ton Hantae-class utility landing craft, to hovercraft that can travel at 80 kph, to rubber rafts launched from larger ships for the purpose of infiltrating along the coast. The amphibious light infantry brigades can also use mini submarines or semisubmersible boats. The navy sniper brigades and the amphibious brigades use the same landing craft, but if all landing craft supported the amphibious brigades, the KPAN could conduct two brigade- and several battalion- or company-size landings along both coasts simultaneously. Once on the ground, these amphibious brigades would attack enemy combat service support units in the rear areas and seize key terrain to facilitate the onward movement of the KPAGF, which are advancing from the north."
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Amphibious Craft, Conventional
7 x
Hanchon LCU -- 117.1 ft LOA, 25.9 ft Beam, 3.9 ft draft; 10 kt top speed.
10 x
Hantae LCU -- 154.2 ft LOA, 21.3 ft Beam, 5.6 ft draft; 22.5 kt top speed. The Hantae most closely resembles an LSM, having an enclosed well deck and clamshell doors at the bow, and was originally designated as such. However, the class is not considered to have a blue-water capability because of its size (only 46 meters long with a beam of 7 meters) and has been redesignated an LCU. These craft can carry 3 to 4 light tanks and are armed with 4 x 25mm Twin Barrel Weapons.
Hantae # Image 1
Hantae Image 2
Operational availability of this class was:
Hantae #1: 1978
Hantae #2: 1979
Hantae #3: 1981
Hantae #4: 1981
Hantae #5: 1983
Hantae #6: 1985
Hantae #7: 1984
Hantae #8: Unknown
Hantae #9: Unknown
Hantae #10: Unknown
18 x
Hungnam LCM 55.8 ft LOA, 14.1 ft beam, 3.9 ft draft; 9 kt top speed. No details or photos available.
99 x
Nampo Fast Personnel Landing Craft (LCP) / (PB) -- This design is based off the Soviet Union's P-6 torpedo boat hull. It has a maximum speed of 40 kts and a combat radius of 335 nautical miles at 28 knots. It is 26 meters long with a bow ramp and clamshell bow doors. It has two twin 14.5mm AA Guns fore and aft. It carries 30 to 35 people. NOTE: At least 22 of the 99 Nampos were converted to Fast Patrol Boats via removing the bow ramp and welding the doors shut.
Image of P-6 Torpedo Boat in Bangladesh for example
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Amphibious Craft, Air-Cushion
2 x
Nampo A/B LCPA Hovercraft
These are a pair of large hovercraft of the dimensions 55.8 ft LOA, 22.6 ft beam and capable of 50 knots top speed. Presumably they are prototypes constructed in the late 1970s and early 1980s to help with development of the Kong Bang production Hovercraft.
136 x
Kong Bang I/II/III LCPA Hovercraft
These are a series of very closely related hovercraft all being roughly the same dimensions:
Kong Bang I: 75.5 ft LOA x 29.5 ft Beam
Kong Bang II: 68.9 ft LOA x 26.2 ft Beam (some sources claim 50 kts and 50 troops)
Kong Bang III: 60.7 ft LOA x 23 ft Beam (some sources claim 40 kts and 40 troops)
Organizationally, they're deployed in Hovercraft squadrons of 16 to 18 hovercraft each, attached to the Amphibious Assault Command of the North Korean West Sea Fleet HQ.
Deployment is at two bases, with two "forward deployment" bases constrructed but currently empty:
Kibong-dong hovercraft base (39.6147°, 124.6325°) built in the 1980s (54 hovercraft shelters)
Tasa-ri hovercraft base (39.8081° 124.4126°) built in the early 1990s (16 hovercraft shelters)
Sasŭlp’o (38.1920° 124.9045°) built 2010-2012; not yet actually used by 2017. (52 hovercraft shelters)
Yami-dong (38.2254° 124.9028°) built 2010-2012; not yet actually used by 2017. (16 hovercraft shelters)(a
(a whole bunch more constructed in the 2010s -- type them up later if I'm serious)
Per CSIS:
"If used as a staging area for an attack, the hovercraft units from Kibong-dong could land as many as 2,700 special force troops on South Korea’s western islands within two to four hours. Units from Tasa-ri could land an additional 800 troops within 2.5 to 4.5 hours of a first wave attack."
CSIS again on the main deployment bases constructed in the 1980s and 1990s:
"The distance from Kibong-dong to the northernmost ROK island of Baegnyeong-do (백령도) is approximately 182 km and to the port city Incheon (인천) approximately 373 km. Under ideal conditions these voyages would take approximately 2 and 4 hours respectively for hovercraft operating from Kibong-dong. If all hovercraft were carrying their maximum number of troops such an attack has the potential to land 2,700 troops in an initial assault wave. Potentially, a second wave could be landed 4-8 hours later."
CSIS again on the forward deployment bases constructed in the 2010s:
"For example, the distances to the northernmost ROK island of Baegnyeong-do (백령도) and the port city Incheon (인천) is reduced from approximately 182 km and 373 km when operating from the Kibong-dong hovercraft base to approximately 50 km and 215 km, respectively, from the Sasŭlp’o and Yami-dong bases. Thus, reducing the voyage time to approximately 30 minutes and 2.5 hours, respectively. Significantly, about half of a voyage from Sasŭlp’o and Yami-dong to Baegnyeong-do would be masked from South Korean radars located on Baegnyeong-do by the Yongyŏn-bando (i.e., Yongyŏn Peninsula) affording a KPN assault on the island a higher degree of surprise."
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Gunboats
54+ x
Chongjin MGB -- Based off earlier Chao design, but with 85mm ZiS-53 gun for fire support.
59+ x
Chaho MGB -- Based off Soviet Project 183 patrol boats.
9 x
Chongju -- this was originally designed to be a fire support unit, with an 85mm gun turret in the bow, and a rocket launcher amidships and reloads on the stern for the rocket launcher, but only one unit was in service with this fire support configuration from 1975-1976, and it was scrapped late in 1976.
Of the 9 x Chongju, three became missile boats, four became patrol craft (85mm gun, 25mm guns, 37mm guns, RBU) and one became a torpedo boat.
Sinhung PT -- At least 74 were constructed between 1966 and 1974. Production then ceased for ten years, before resuming in February 1981 and by the Fall of 1982, the North Koreans had at least 92; rising to 120 in 1983 before Sinhung production was terminated that year for the second time. They basically have torpedoes and a pair of fore and aft 14.5mm HMGs.