Midget Submarines

[shubhamsaikia]

A midget submarine is any submarine under 150 tons[citation needed], typically operated by a crew of one or two but sometimes up to 6 or 8, with little or no on-board living accommodation. Midget submarines normally work with mother ships, from which they are launched and recovered, and which provide living accommodation for the crew and other support staff. Both military and civilian midget submarines have been built. Military types work with surface ships and other submarines as mother ships. Civilian and non-combatant military types are generally called submersibles, and normally work with surface ships. Most early submarines, such as the United States Navy's USS Holland (SS-1) and the British Royal Navy's Holland 1, would now be considered midget submarines.

The best known role for midget submarines is probably harbor penetration, although only two World War II boats, the British X-craft and the unsuccessful Welman submarine were specifically designed with this in mind. Japan's Ko-hyoteki class submarines were originally designed to take part in decisive fleet actions. However, as circumstances changed, they ended up tasked with harbour penetration. Germany's various World War II designs were mostly designed to attack Allied shipping off landing beaches and harbours, although the Seehund had a great enough range to attack shipping off the Thames estuary. Midget submarines have also seen some use in support roles. X-craft were used for reconnaissance, and the Seehund was used to carry supplies. A number of modern midget submarines have also been built for submarine rescue.

 

[shubhamsaikia]

Shinnkai 6500

 

[shubhamsaikia]

X-24

 

[shubhamsaikia]

USN X-1

 

[shubhamsaikia]

 

[shubhamsaikia]

North Korea's Midget Submarine sank a South Korean Corvette killing 46 Sailors
War tensions have been high since last week's announcement by the South Korean government that a 60-foot North Korean submarine fired a torpedo that sank a South Korean corvette and killed 46 sailors at the end of March. The South Koreans stated that a Yeono-class (alternatively spelled "Yono") midget submarine fired the torpedo in March. (They also field a larger midget submarine, the Sang-O, that fits 15 sailors. At least one of these subs was also on patrol when the attack happened, according to an international team of investigators looking into the incident with South Korea.) The attack occurred in 150 feet of water, enough room for the midget submarine to maneuver. Any sub that weighs less than 150 tons is called a midget. They can't travel too far on their own, and depend on support vessels to extend their range. In shallow water, where sonar returns are cluttered, they can prove quiet and sneaky. Often this means they can lay mines or insert commandos on beaches. According to statements by South Korea, attacks from midget subs can also include torpedoes. Iran is known to operate midget subs, and after buying a handful from North Korea, it is believed to be making its own. A civilian ship hired to dredge the area of the attack found remains of what the government labeled a CHT-02D torpedo, made in North Korea. That torpedo would have a big enough warhead—250 kilograms—to destroy the corvette. Government reports state that the ship's sonar did not detect the submarine or the torpedo.

That is what concerns the U.S. Navy. Two things heighten the risk of a similar ambush by midget submarines against U.S. ships: the complex sonar picture of shallow water where these small subs can operate, and a post–Cold War decrease in anti-submarine training. "Instead of a large number of Soviet nuclear-powered submarines on the open ocean, advanced conventional submarines operating in the littorals have emerged as the most serious threat to U.S. forwardly deployed forces, military sealift and merchant shipping," Milan Vego, professor of operations at the Joint Military Operations Department at the Naval War College, wrote in a recent piece for Armed Forces Journal. "The emerging threats ... are minisubmarines, swimmer-delivery vehicles, remotely operated vehicles and autonomous underwater vehicles." This week the Pentagon announced it would step up its anti-submarine training, engaging in exercises with South Korea. The decision is "a result of the findings of this recent incident," Pentagon spokesman Bryan Whitman told reporters. But crash courses in sub hunting may not help much; professionals admit it's an art as much as a science. The United States' sub-hunting abilities have atrophied since the Soviet Union dissolved. One obstacle to revamping anti-submarine training is bringing it out of simulators and into the real world. It takes a lot of effort to conduct a real sub hunt, but these skills need to be continuously honed. "The skills for successful conduct of anti-submarine warfare (ASW) must be maintained; otherwise, they will quickly atrophy," Vego warns.

The Navy has done a better job spending money on technology that can locate submarines. During the Cold War, permanent networks of sensors on the sea floor helped keep tabs on Soviet submarines. Similar networks have not been established or upgraded for use in new hotspots. "Undersea surveillance systems developed during the Cold War have limited effectiveness today," Vego says. It appears the South Koreans share that lethargy, but South Korean officials now say a permanent snooping system will be installed. South Korean Lt. Gen. Park Jung-e said at a media briefing that "our plan is to reinforce submarine measures by establishing a submarine detection system in areas that are vulnerable." The United States is also fielding a deployable piece of underwater detection technology, called the Advanced Deployable System (ADS), that is built for shallow-water emergencies. The system proposes to use expendable, battery-powered passive acoustic arrays that are connected with fiberoptic cables. The system will be integrated into the Navy's much-delayed but recently commissioned Littoral Combat Ship.

 

[asianobserve]

Shinnkai 6500

Is this an attack sub? It looks like a deep sea submersible...

 

[shubhamsaikia]

Is this an attack sub? It looks like a deep sea submersible...

This is a submersible. Midget submarines for warfare is curently only in operation with Iran and N Korea. So will have to dig into that.

 

[asianobserve]

What kind of midget sub is this? What's the nationality (are those Swedish markings on the tower?)? It looks recent to me...

 

[Kunal Biswas]

What kind of midget sub is this? What's the nationality (are those Swedish markings on the tower?)? It looks recent to me...

The Spiggen II Class..

 

[Kunal Biswas]

3rd Class submarines

This class includes the smallest of the Japanese submarines, particularly midget types down to kamikaze manned torpedoes.

Ko-Hyoteki Type (50 units)

The Ko-hyoteki class of Japanese midget submarines had hull numbers but no names. For simplicity, they are most often referred to by the hull number of the mother submarine. Thus, the midget carried by I-16 was known as the I-16 midget. The midget submarine hull numbers beginning with the character "HA", which can only be seen on a builder's plate inside the hull.

Fifty were built. The "A Target" name was assigned as a ruse - if their design was prematurely discovered by Japan's foes, the Japanese Navy could insist that the vessels were battle practice targets. They were also called "tubes" and other slang names.

Kairyu Type (250 units)

The Kairyu was a class of Kamikaze midget submarines designed in 1943-1944, and produced from the beginning of 1945. These submarines were meant to meet the invading American Naval forces upon their anticipated approach of Tokyo.

Over 760 of these submarines were planned, and by August 1945, 250 had been manufactured, most of them at the Yokosuka shipyard.

These submarines had a two-man crew and were fitted with an internal warhead for suicide missions.

Kaiten Type (1000 units)

The Kaiten was a torpedo modified as a suicide weapon, and used by the Imperial Japanese Navy in the final stages of the Second World War. Kaiten means turning of the heavens.

Early designs allowed for the pilot to escape after the final acceleration towards the target, although whether this could have been done successfully is doubtful. There is no record of any pilot attempting to escape or intending to do so, and this provision was dropped from later production kaitens.

Five models were designed, the Types 1, 2, 3 and 4 based on the Type 93 torpedo (24 inch oxygen/kerosene), and the Type 10, based on the Type 92 torpedo (21 inch electric). Types 2, 4 and 10 were manufactured in small numbers and never used. Prototypes of the Type 3 may have been built, or it may have existed only as a concept

 

[Kunal Biswas]

Ghadir class submarine

 

[Kunal Biswas]

 

[Kunal Biswas]

SX-404

SX-404 was Cos.Mo.S' first known venture into midget submarine design and production. This was a 40-ton boat intended to transport naval SOF operators into hostile waters over distances greater than those that could be achieved by the company's Chariot swimmer delivery vehicles (SDVs). All Cos.Mo.S' midget submarines were designed with the capability of carrying two of the company's CE2F-series SDVs.

Cos.Mo.S built two subvariants of this design, the SX-404, two examples of which were delivered to Taiwan, and the SX-404/B, six of which were delivered to Pakistan. The two subtypes are easily distinguished from each other by the presence or absence of a large horseshoe step on the sail. Pakistan's SX-404/Bs have this step, Taiwan's do not.


Displacement: 40 tons
Length: 59.1 feet
Width: 6.5 feet
Draft: 8.4 to 10.4 feet
Surface Speed: 10kts (designed), actual 4kts
Submerged: 7.2 kts
Max depth: 131.2 feet
Range: 1235 nautical miles
Crew 4 Officers, 2 NCOs, 6 passengers
Payload: 2 SDVs (CE2F Chariots)

 

[Kunal Biswas]

SSA Cosmos SX-506 class

(Italy)

Notes: Classified as "tactical submarines" these built-for-export small subs have no combat potential but are useful for frogman insertion, reconnaissance, minelaying, and a number of other tasks. They have a combined snorkel/antenna mast that sits flush with the aft deck and is raised horizontally. Other than a small safety-of-ship passive hydrophone, they have no sensors. They can not carry torpedoes.

Three units were purchased by Pakistan in in 1972. Homeported in Karachi, their names (if any) are unknown. They were discarded in 1992.

Two units (ARC Intrepido SS-20 and ARC Indomable SS-21) were purchased by Colombia in 1972 and overhauled (including being enlarged) in 1984. In contrast to the low popularity of midget submarines elsewhere, they are very well-liked and remain in full service. Both are attached to the Caribbean fleet.

Displacement: 75t surfaced, 90t submerged
Dimensions: 75'5"x13'1"x13'
Machinery: Electric: 1 Cummins 300H diesel generator, 1 electric motor + 4 (2 AC, 2 DC) 1100Amp lead-acid batteries, 1 shaft
Max speed: 8kts surfaced, 6kts submerged
Range: 1200NM @ 8kts surfaced, 10 hours @ 6kts submerged)
Endurance: 2 weeks
max Diving depth: 350'
max Complement: 4 + 8 frogmen

WEAPONS: Can carry two SDV + 2 tons of cargo; alternatively can carry external chassis for eight small mines

Note: SX-506s are almost indistinguishable externally from SX-756s. The two Colombian boats can be distinguised from one another when their snorkel masts are raised. The ball mechanism on top of Intrepido's mast is flattened, whereas Indomable's is spherical. Both are distinguishable from South Korea's SX-506s by the step mounted around the sail, which is absent on the Korean units. Colombia's SX-506s are sometimes referred to as SX-506/B as a result of their lengthening, however this designation is not used by the Colombians, who usually refer to them as "Submarinos Tacticos."


Armament:
8x explosive charges from 50kg to 2050kg, including the charges onboard chariots.
Mines: 6x Mk-21; 8x Mk-50

 

[Kunal Biswas]

Cosmos Class MG-110/LR submarine

The Naval Special Services Group (SSGN), numbering 1,000 marines, is responsible for conducting unconventional operations at sea and along the shoreline. Delivery or insertion of maritime special forces includes fixed- wing/helicopter low-level parachuting, light craft beaching and underwater conveyance, for which the navy operates at least three Cosmos Class MG110 miniature submarines (SSI) and some swimmer- delivery vehicles.

On the basis of design developed by PN Dockyard, this type of mini submarine has been constructed at PN Dockyard. These mini-submarines can be used for various purposes like attacking enemy units in harbour with Frogmen/Charriots, at sea with torpedoes, at shore installations by commandos etc. other uses include mine laying, defensive barrier in shallow waters, advance pickets duties, intelligence gathering etc.

Although the Italian Navy pioneered the use of human torpedoes (known today as swimmer delivery vehicles or SDVs), in today's Italian Navy there are no midgets. However Cosmos of Livorno has sold a number of midgets abroad. The SX 404 type sold to Pakistan in the early 1970s have been replaced by three [or possibly four] Italian-built SX-756-class midget submarines, delivered in 1988. These displace 40 tons and are capable of diving to a depth of 100m. They can carry six swimmers and two SDVs, as well as 2 tons of explosives.

X-Craft 908 P/A as Shallow Water Attack Submarine(SWAS) is used to carryout mine laying torpedo attack, frogman operations and commando landing. The contract of these mini submarines was signed with Italian firm M/s COSMOS in 1986. First of these craft was brought to Pakistan in semi knock down condition in 1988. Subsequently all X-Craft were assembled in Pakistan with TOT. Presently, X-Craft are being operated under COMSUBS alongwith other conventional submarines.


Length overall 27.28 meters
Height overall 5.59"
Pressure Hull Diameter 2.30"
Pressure Hull Length 19.10"
Displacement
102 tons (surfaced),
110 tons (sub-merged)

Operation Depth In excess of 100 m
Test Depth In excess of 100 m
Max. speed (surfaced) 9 KTS (on diesel engine)
Max. speed (submerged) 6 KTS (on batteries)
Endurance Over 1000 NM on diesel engine, Over 40 NM on batteries
Complement 14 (6 operators + 8 commandos)
Armament Torpedo Firing Tubes, Mine Laying Hooks

 

[asianobserve]

Sea Dagger Special Operations, Sweden

The Sea Dagger series of submarines are special operations vehicles developed by Kockums of Malmo, Sweden, now owned by HDW of Germany. The small stealthy submarines are tailored for five types of missions: attack; autonomous swimmer delivery; surveillance and minehunting; and as a target vehicle for antisubmarine warfare exercises and training.

The Sea Dagger variants are constructed from three modules, the bow and stern modules and one chosen from four specific mission module options. The submarines are small, with displacement in the range of 55t to 72t, a length of between 16 and 20m, a height of 3.6m and a diameter of 2.5m.

The four variants of Sea Dagger are equipped with sonar, communications systems, and a comprehensive navigation suite including a navigation computer, a gyroscope compass, speed log, depth gauge, echo sounder, global positioning system, navigation radar and optronic mast.

PROPULSION

The diesel electric engine provides a surface speed of 6 or 7 knots according to the submarine configuration, and a submerged speed of 8 knots. The operational endurance is eight days (five days for the Advanced Target Submarine). The range is 2 x 350 nautical miles at 4 knots (3 knots for the ATS), and 70 nautical miles under battery power at 4 knots (35 nm at 3 knots for the ATS). The surface speed is 7 knots and the underwater speed 8 knots. The operational endurance is eight days (five days for the ATS).

SEA DAGGER SMALL ATTACK SUBMARINE

The Small Attack Submarine has the capability to carry and launch externally stowed weapons. A range of half-length anti-submarine warfare (ASW) weapons and mines can be carried. The submarine is operated by a crew of four, with two combat system operators. The rescue chamber can accommodate single escape or lockout.

The attack submarine is fitted with passive, intercept and obstacle avoidance sonar. The communications systems include VLF/LF, HF, and VHF antennae, internal and external communications, an underwater telephone system and a diver communications system.

The submarine's combat systems include a command and control system, electronic support measures, two external torpedo tubes and a weapons launching system.

SEA DAGGER AUTONOMOUS SWIMMER DELIVERY VEHICLE (ASDV)

The ASDV Autonomous Swimmer Delivery Vehicle carries, delivers and retrieves combat swimmers. The operational endurance is eight days. The vehicle carries no external weapons.

The submarine is operated by a crew of four and can accommodate up to six divers. A lockout chamber allows four divers to exit simultaneously.
The ASDV has passive, intercept and obstacle avoidance sonar. The communications suite includes a VLF/LF antenna system, HF and VHF antennae, external and internal communications, underwater telephone system and a diver communication system.

SEA DAGGER ADVANCED SURVEILLANCE VEHICLE (ASV)

The Advanced Surveillance Vehicle is equipped for surveillance and minehunting operations. An electronic support measures system is installed on the submarine. The communications system provides transfer of surveillance data. The submarine is operated by a crew of four, with two surveillance and minehunting system operators.

The submarine has passive, intercept and obstacle avoidance sonar. The communications systems on the surveillance vehicle are VLF/LF, HF and VHF antennae, external and internal communications, underwater telephone and diver communications.

SEA DAGGER ADVANCED TARGET SUBMARINE (ATS)

The Advanced Target Submarine, ATS, provides a target vehicle for Anti-Submarine Warfare (ASW) training primarily for littoral warfare training. A variety of signatures and target signal strengths can be generated by the target simulator. The ATS is operated by a crew of three and the operational endurance is five days.

The Advanced Target Simulator is equipped with an obstacle avoidance radar, a VHF antenna system, external and internal communications and an underwater telephone system.

 

[Kunal Biswas]

SX-756-class midget submarines

The South Korean Navy operates six or eight Dolphin class mini-submarines. These SX 756-class midget submarines are based on the Italian Kosmos design. These mini-submarines are otherwise very poorly attested, The SX-756 submarines were the first of a new design by Cosmos of Livorno. The first 3 craft were sold to Pakistan in kit form and arrived in Karachi in 1988. When the deal for the submarines was signed, it was no coincidence that Adm Tariq Kamal Khan was CNS. As a former SSGN and first CO of PNS Iqbal following its commission on 29 March 1967, he understood full well the potential of SOF and unconventional warfare. Cosmos marketed the submarine as the MG-110 along with another variant known as the MG-120ER. The latter is known to be in service with Italy, South Korea and Columbia. The SDV's delivered to PN in the 1970's are no longer in use and were withdrawn from service in the late 90's. Some of thse SDV's now serve as reminders of a past era for SSGN as part of a display at the Maritime museum in Karachi.

SX-756 are equipped to carry torpedoes, mines and/or combat divers. They have been modernised during the late 90's to help keep them in service. One of the X-craft was lost at sea in 1995. However there were no fatalities and the Midget was recovered, repaired and subsequently returned to service

 

[shubhamsaikia]

India should also look at such Subs.. Incase of any confrontation with Pakistan. Infiltrating Karachi with these

 

[W.G.Ewald]

A Japanese Type C was on display at the Mystic Marine Museum in Connecticut for many years, as I remember.