Engineering:Type 4 Ka-Tsu
| Type 4 Ka-Tsu | |
|---|---|
 A Ka-Tsu on display | |
| Type | Amphibious armored personnel carrier |
| Place of origin | Empire of Japan |
| Production history | |
| Designed | 1942–1943 |
| No. built | 49[1] |
| Specifications | |
| Mass | 16 tons[1] |
| Length | 11 m |
| Width | 4 m |
| Height | 2.25 m |
| Crew | 5 |
| Armour | 10 mm[1] |
Main armament | 2x torpedoes[2] |
Secondary armament | 2x 13 mm machine guns[1] |
| Engine | gasoline (petrol) in a water-tight pressure box 62 HP |
| Power/weight | 3 HP/1 ton |
| Suspension | - |
Operational range | - |
| Speed | (sea) 5 knots |
The special Type 4 Launch Ka-Tsu (特四式内火艇 カツ toku-yon-shiki uchibitei Ka-Tsu) was a Japanese amphibious landing craft of World War II. The first prototype was completed in late 1943 and trials were conducted off Kure in March 1944.
History
Japan's combat experience in the Solomon Islands in 1942 which revealed the difficulty of resupplying Japanese forces in such situations prompted the IJN to commence an amphibious tractor program in 1943, as the Ka-Tsu,[3] which was designed by Commander Hori Motoyoshi of the Kure Naval Yard.
Design
The Ka-Tsu's primary purpose was to transport cargo and/or troops ashore.[2] It had light armored shielding with a maximum of 10 mm.[1] Its engine compartment and electric final drives were hermetically sealed, as it was intended to be launched from a submarine.[3] The twin drive propeller shafts were designed to retract "into their ducts" once the vehicle reached the beach.[2]
The first prototype was completed in late 1943 and trials were conducted off Kure in March 1944.[3] By the time development had been completed, it was proposed that the Ka-Tsu be used to attack US battleships anchored in atolls (such as Ulithi), which could not readily be attacked using conventional means. It was proposed that a Ka-Tsu armed with a pair of naval Type 93 torpedoes[4] be dropped off by submarine away from the atoll, propel itself to the outer reef using its tracks, and then enter the lagoon on the inside of the reef. Tests were successfully carried out with a modified Ka-Tsu carrying two torpedoes on its deck, but the war ended before any such mission could be mounted and the Ka-Tsu deployed in combat.[3] A total of 49 units were produced.[1]
Operation Tatsumaki
In May 1944, the submarines missing name, missing name, missing name, missing name and missing name and the auxiliary submarine tender missing name began training in the Seto Inland Sea off Nasakejima for Operation Tatsumaki ("Tornado"), which called for the submarines to transport modified Ka-Tsu, each armed with two 450 mm (18 in) torpedoes, from Kure to Majuro.[5] [6] After the submarines launched the Ka-Tsu vehicles, the operation called for the vehicles to proceed to shore, move overland across the atoll's islands, then enter the water in the lagoon and attack Allied ships with torpedoes.[5][6] Operation Tatsumaki was thereafter postponed pending the correction of defects found in the Ka-Tsu vehicles[7] and eventually was canceled entirely.[5]
Gallery
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Type 4 Ka-Tsu with machine guns mounted -
Rear-side angle view of Type 4 Ka-Tsu -
Two Type 4 Ka-Tsu with torpedoes on the deck of a IJN submarine
See also
- Blockade Runner
- Type 3 submergence transport vehicle
- Ha-101 class submarine
Notes
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Taki's Imperial Japanese Army: Type 4 Amphibious Vehicle "Ka-Tsu"
- ↑ 2.0 2.1 2.2 Tomczyk 2003, p. 33.
- ↑ 3.0 3.1 3.2 3.3 Zaloga 2007, p. 24.
- ↑ Tomczyk 2003, pp. 33, 37.
- ↑ 5.0 5.1 5.2 Hackett, Bob; Kingsepp, Sander (2014). "IJN Submarine I-44: Tabular Record of Movement". combinedfleet.com. http://www.combinedfleet.com/I-44.htm.
- ↑ 6.0 6.1 Hackett, Bob; Kingsepp, Sander (2019). "IJN Submarine I-53: Tabular Record of Movement". combinedfleet.com. http://www.combinedfleet.com/I-53.htm.
- ↑ Hackett, Bob; Kingsepp, Sander (2019). "IJN Submarine I-36: Tabular Record of Movement". combinedfleet.com. http://www.combinedfleet.com/I-36.htm.
References
- Tomczyk, Andrzej (2003). Japanese Armor Vol. 3. AJ Press. ISBN 978-8372371287.
- Zaloga, Steven J. (2007). Japanese Tanks 1939–45. Osprey Publishing. ISBN 978-1-8460-3091-8.
External links
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