The japanese armour and other vehicles thread

Discussion on the tanks and other armoured fighting vehicles, which participated in World War 2.
tom!
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Re: The japanese armour and other vehicles thread

Postby tom! » Tue Jun 25, 2013 9:29 am

Hi.

For a first impression I recommend

http://www3.plala.or.jp/takihome/formation.htm
planned OOB

http://www3.plala.or.jp/takihome/history2.htm
short overview over the battles

More will follow later.

Yours

tom! ;)

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Re: The japanese armour and other vehicles thread

Postby canambridge » Wed Jun 26, 2013 12:59 pm

Thanks tom!

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Re: The japanese armour and other vehicles thread

Postby tom! » Wed Jun 26, 2013 5:00 pm

Hi.

Infos on 2nd Tank Division (2TD) during the Philipines Campaign are rare and a little bit confusing. The links in my upper post are not latest state of the art. Here´s what I could find out:

1. Regarding OOB:

2TD was formed im March 1942 in Manchuria and assigned to Kwantung Army. The main force consisted of 3rd Tank Brigade with 6th and 7th Tank Regiment, 4th Tank Brigade with 10th and 11th Tank Regiment. Divisional units were formed following the planned OOB as far as possible. The divisional units were originally designated after the division, e. g. "2nd Tank Division Mobile Infantry Regiment","2nd Tank Division Mobile Artillery Regiment" etc. Later (no exact date found so far) several units received a designation without the "Tank Division", e.g. "2nd Mobile Infantry Regiment", "2nd Mobile Artillery Regiment" etc., while other still used the old designation, e.g. "2nd Tank Division Rapid-Fire Gun Unit" (AT-gun unit), "2nd Tank Division Engineer Regiment" etc.

There is a lot of confusion around the reorganisations made after 2nd Tank Division reached Luzon in July 1944. At the same time 6 Independend Tank Companies (7th to 12th ITC) were transported to Luzon. There were quite a lot of losses so these units were partly reorganised.

- 7th ITC: Minor losses during transport, received some tanks from 11th TR.
- 8th ITC lost one platoon of 3 tanks. It was was disbanded and absorbed by 10th TR.
- 9th ITC had minor losses and became main body of the new 8th ITC
- 10th ITC lost all tanks and vehicles plus half of the personnel. Remaining soldiers were assigned to the new 8th ITC
- 11th ITC had minor losses and became main body of the new 9th ITC
- 12th ITC lost all tanks and a few soldiers. The rest was used to form the new 9th ITC, surplus men and vehicles were absorbed by 10th TR

2nd TD was also reorganised. 11th TR was renamed 27th TR and shipped to Okinawa but only with 12 light and 14 medium tanks. The other tanks were used to reequip the other three regiments. 4th Tank Brigade was abandonned and 10th TR was assigned to 3rd Tank Brigade.

Then 2nd TD was assigned to Yamashita´s 14th Area Army. The 2nd Mobile Infantry Regiment (MIR)was stationed at Clark Field and on Bataan, the rest of the division in the north near the Gulf of Lingayen. Yamashita was a superb infantry commander (he was the head behind the Malaya Campaign in 1941/42) but he saw tanks just as support weapon. Instead of 2nd MIR several other units were assigned to 2nd TD:

- 356th Independend Infantry Battalion
- Matsumoto Battalion (part of 3rd Battalion, 26th Infantry Regiment)
- Kataoka Unit (part of 63rd Infantry Regiment)
- Dry Battalion (part of 39th Infantry Regiment)
- Suzuki Unit (formed from several rear echelon army units)
- one company, Maeda Unit (part of 63th Infantry Regiment)
- 9th ITC
-one platoon, Semba Independend Rapid-Fire Gun Company
- one platoon, 3rd (bridgebuilding) Company, 10th Independend Engineer Regiment
- Line of command hospital 134
- Line of command hospital 138
- Line of command hospital 139


After the US landings at Lingayen the 2nd TD was withdrawn into the mountain territory north of Clark Field and reorganised. Now the following units were assigned to the division:

- 2nd Battalion, 11th Independend Infantry Regiment
- Ishii Battalion (4th Battalion, 10 Field Artillery Regiment, without guns)
- Hidaka Railway Guard Battalion
- Okano Unit (11th Company, 63rd Infantry Regiment)
- Yamashita Unit (formed from 4th Field Replenishment unit)
- Kisuki Unit (formed from 7th Field Replenishment Unit)
- Mine Unit (formed from personnel of Manila Aviation Plant and 65th Flight Squadron)
- Shirane Unit (13th Temporary Infantry Battalion, formed from IJA sailors)
- Saito Mountain Gun Platoon
- Ueyama Headquater Unit (commanding unit of 1st Temporary Infantry Group)
- Morishita Battalion (19th Temporary Infantry Battalion, formed from 7th Air Signal Regiment)
- Yano Battalion (17th Temporary Infantry Battalion, formed from IJA naval units around Manila)
- Kim Unit (formed from personnel of IJA and IJN education units stationed on Luzon)
- 88th District Commisariate Unit (No idea what that is....)
- Matsuo Unit (formed from 7th Field Replenishment Unit)
- Fukaya Battlion (15th Temporary Infantry Battalion)
- Tokunaga Battalion (62nd Independend Transport Battalion)
- Inoue Battalion (63rd Independend Transport Battalion)
- 49th Road Construction Unit
- Matsubara Battalion (178th Independent Infantry Battalion)


2. regarding equipment:

- The tank regiments were equipped with the well known light and medium tanks. The exact composition of teach TR is unknown to me. 6th and 7th Tank Regiment still had Type 89 Medium Tanks (at least one company each). These were mainly used as mobile pillboxes.

- A MIR was equipped with passenger cars, Type 95 Cars, Type 95 Motorcycles with sidecars for the command sections. The battalions should be mechanised with the halftracked Type 1 APC Ho-Ha and the full tracked Type 1 APC Ho-Ki.

Image
Type 1 APC Ho-Ha

Image
Type 1 APC Ho-Ki

Production numbers of these vehicles are unknown but not too high. I don´t know if 2nd TD had them but there are no reports of such vehicles being used on Luzon. In similar units often various truck types were used for transport instead.

- The artillery regiment used Type 98 4t Prime Movers Shi-Ke for gun transport. The guns had special wheels and springs for fast transport.

Image
Type 98 4t Prime mover towing a Type 90 75 mm Field Gun

- The rapid-fire battalion used trucks to tow their Type 1 47 mm Rapid-Fire Guns

- The AA-regiment used trucks for their Type 98 2 cm Machine Cannons and Type 98 Halftracked Prime Movers Ko-Hi for the Type 88 75 mm AA-Guns. To increase mobility Type 98 Machine Cannons were mounted on trucks or halftracks.

Image
Type 98 Halftrack Ki-Ho with mounted 2 cm machine cannon

- The engineer regiment operated 20 SS-Ki vehicle with bridges and obstacle clearing equipment mounted

Image
SS-Ki without bridge

- There was no standardisation regarding the trucks used by the division. Everything availiable was taken including civil vehicles.

Yours

tom! ;)

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Re: The japanese armour and other vehicles thread

Postby tom! » Thu Jun 27, 2013 10:52 am

16) Army Amphibious Tanks

A less known fact is that IJA was quite busy developing amphibious vehicles in the 1930th. Starting with the the Experimental Amphibious Halftrack AMP at least five different vehicles were developed and tested. As all trials were finally cancelled informations are rare.


A) Ishikawajima Amphibious Tank

Image

The tests with the AMP showed that such a vehicle would be useful for reconnaissance duties. So after introduction of the Type 92 Heavy Armoured Car Ishikawajima was ordered to develop an amphibious version of this tank, too. This was done until 1933. The official designation is unknown.

The vehicle used suspension, turret, engine and steering from the Type 92. The armour scheme was changed massively. The bow armament extension was removed and the driver was shifted to the center. A boat-shaped hull and large floats on the bow, sides and rear made the vehicle suitable even for heavier swell. Small propellers and rudders next to the tracks allowed manoevring in the water. Armour strength is unknown but did not exceed the one from basic vehicle (6 mm maximum).

Tests were quite satisfying and a small (unknown) number of pre-series vehicles was built for operational tests, too. Details are unknown but the final results lead to the decision to drop this design in favour of a special development program. The existing vehicles were later used for exercises and then scrapped.

Data

unknown



B) SR I-Go

Image

After finishing the tests with the Ishikawajima Amphibious Tank IJA ordered Mitsubishi to develop a new design for such a vehicle. Requirements are unknown but it seems that a vehicle weight below 4 t was one of basic demands.

The prototype was finished in 1934. The suspension was similar to the one used on the Engineer Vehicle SS-Ki. It consisted of eight roadwheels, three return rollers, a rear driving sprocket and a frontal idle wheel. Each two pairs of roadwheels were connected by leaf springs and mounted on the hull. The hull had several seperate chambers to retain buoyancy if pentetrated by bullets or splinters. The bow was not really boat-shaped. The driver sat below a cylindrical cupola in the (in driving direction) right. A simple visor port was used. The commander/gunner operated a Type 91 6,5 mm Tank MG inside a small conical turret in the centerline of the vehicle. Both had a large two-door access hatch above their position to enter the tank. All armour plates were riveted.

Image

Afoat a small rudder below the rear allowed steering. Propulsion was generated simply by operating the tracks, there was no propeller. A large hingeable steel plate mounted on the frontal bow armour was used as splash shield.

The final weight without armament and anmmunition was just 3,7 t which indicates that the armour strength was very low. During the innitial tests the vehicle reached a maximum speed of 24 km/h on land with a 70 hp gasoline engine. The maximum speed of 9 km/h afloat could only be reached after a long acceleration periode. This propulsion was rated too weak. In addition the small rudder made steering problematic. Armament and armour waere also rated too weak. So this design was dropped.

Image

The prototype was used during exercises and was last seen on a parade in China in summer 1938. After development of its successor the numbering suffix "I-Go" = "Version 1" was added to the vehicle designation. Short designation became SR-I.

Data

vehicles built: 1
weight: 3,7 (metric) t
crew: 2 men
length: 4950 mm
width: 2400 mm
height: 1650 mm
engine: Mitsubishi 4-cylinder gasoline engine
power: 70 hp
maximum speed: 24 km/h on roads, 9km/h afloat
armament: 1 X Type 91 6,5 mm Tank MG



B) SR Ro-Go

Image

The problems with the SR-I led to the decision to start a new trial in late 1934. This time Ishikawajima was in charge of development again. Now weight should be up to 7 t, maximum armour strength 10 mm. A second MG should increase firepower.

The prototype was finished in mid 1935. It had a completely new Horstmann-type suspension consisting of three roadwheels, one return roller, a frontal driving sprocket and a rear idle wheel. The two forward roadwheels were connected by a small coil spring and a bogie. The rear roadwheel was connected the same way with the idle wheel. The roaswheel was placed between the second and third roadwheel. The bow was now boat-shaped increasing acceleration afloat. An armour plate integrated in the middle of the bow armour could be raised as splash shield.

On the bow and each side several flotation chambers were mounted. These were designed flatter to lower the silhouette. The driver now had a rectangular cupola with visor ports on the front and right side. He entered the vehicle through a large rectangular hatch above his position. On his left side the bow gunner was placed below a slightly larger rectangular cupola. A cap on his hatch increased his firing angle. He operated a Type 91 6,5 mm Tank MG in a standard mount. A closable visor port was placed in the left side next to the gunner.

The turret had an octogonal basic shape with sloped sides. A standard MG mount for a Type 91 6,5 mm Tank MG was mounted in the frontal plate. Closable visor ports were placed in each forward side and side armour plate and in the rear. The commander/gunner entered the tank through a large access hatch with a big cap. A grid construction behind the turret simplified access to the vehicle afloat.

Image

The engine was placed lengthwise in the rear. Exhaust pipes lead from the rear to a muffler and raised tail pipes behind the turret on each side. Two 500 mm propellers with rudders were attached to the rear.

The vehicle was designated " SR Ro-Go " = Amphibious Tank Version 2, short designation SR-II. During innitial tests the vehicle showed a good mobility on land and afloat. A small pre-production series was finished until late 1935. Operational tests were successful but the armament was rated too weak. Nevertheless the concept was rated good.

The fate of the vehicles is unknown. At least one was captured 1945 by soviet units in Manchuria. There is no known survivor.

vehicles built: >1
weight: 6,9 (metric) t
crew: 3 men
length: 4100 mm
width: 1800 mm
height: 1600 mm
engine: gasoline engine
armament: 2 X Type 91 6,5 mm Tank MG



B) SR Ha-Go

no picture, sorry.

In late 1935 Mitsubishi was ordered to remodel the SR-II design. Goal was to increase firepower and armour. Only limit was a maximum weight of 7,5 t.

The basic shape was not changed.To get a stable gun platform afloat the flotation chambers were enlarged to the sides and front. Welding was used instead of rivets as far as possible to spare weight. The maximum armour was increased to 13 mm. The turret was enlarged and the hatch on top of it was seperated into two to prepare the implementation of a gunner. A prototype was built until mid 1936 designated "Amphibious Tank Version 3", short Designation "SR-III" or SR Ha-Go".

Trials to mount a Type 94 37 mm Tank Gun lead to a maximum weight above 7,5 t. This was also rejected as the proposals to mount a Type 92 13,2 mm Tank Machine Cannon or to lower the armour strength to reach 7,5 t. Mitsubishi saw no chance to archive the expected result with the weight limit. In addition there was a lack of ressources regarding production capacities, raw materials and money. So IJA decided to cancel the whole project in early 1937. The development results were handed over to IJN.

The prototype was sent to Rabaul in 1942 or 1943 for further tests and transport purposes. The remains are on display at Kokopo Museum, Rabaul

vehicles built: 1
weight: 7,5 (metric) t
crew: 3 men
length: 4100 mm
width: 2000 mm
height: 1800 mm
engine: gasoline engine
armament: 1 X Type 91 6,5 mm Tank MG


edit 12.12.2015:
added Infos about the fate of the SR III prototype

Yours

tom! ;)
Last edited by tom! on Sat Dec 12, 2015 8:26 am, edited 3 times in total.

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Re: The japanese armour and other vehicles thread

Postby canambridge » Thu Jun 27, 2013 1:31 pm

Thanks for the great stuff tom! Keep it coming.

tom!
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Re: The japanese armour and other vehicles thread

Postby tom! » Thu Jun 27, 2013 5:41 pm

Hi.

17) Navy Armoured Vehicles

The Imperial Japanese Navy used AFV since the First Shanghai Incident in 1932. First vehicles were domestic and foreign armoured cars like the Type Crossley Armoured Car or the Osaka Armoured Car. The first tank unit was raised in 1936 as part of the Tokubetsu Rikusentai = Special Naval Landing Forces (japanese Marines). It was equipped with standard Type 89 Medium Tanks. Later navy tank units were based on various pacific islands equipped with Type 95 Light Tanks, Type 97 Medium Tanks and Type 97 Medium Tanks KAI. IJN tanks used an anchor instead of a small yellow star as national emblem. Several units also painted the Rising Sun Flag (the navy war flag) on their tanks. IJA units only used the Hinomaru Flag (the army war flag) on captured tanks to mark them as own vehicles. After 1940 IJN developed several special tank and armoured vehicle types which are covered here.


A) Special Type 2 Motor Launch

Image
After taking over the results of the army amphibious tank project in 1937 IJN start to think about how to use this kind of vehicles for amphibious operations of their Special Naval Landing Force (SNLF). Several studies were made regarding potential operational use, necessary features and possible tactics. With the decision to start a war in the Pacific in 1940 IJN increased the efforts and in early 1941 the decision was made to develop an amphibious tank. In cooperation with Army Technical Bureau and Mitsubishi such a vehicle should be built based on the Type 95 Light tank. Requirements were among others:

- watertight construction
- fully seaworthy even in heavy weather
- fully welded
- range afloat at least 100 km
- speed afloat 10 km/h
- floating devices removable from inside
- armament consisting of a Type 98 37 mm Tank Gun and two Type 97 7,7 mm Tank MGs
- easy to be build

The first tests with the incomplete prototype started in late 1941 at Lake Hamada, Shizuoka Prefecture. The vehicle was finished until early 1942. It consisted of the tank, two large detachable pontoons, a detachable conning tower and a detachable special air intake extension. All hatches openings and holes were made watertight by rubber seals or bulletproof glass. Crew consisted of driver, bow gunner, commander, gunner, ammunition supplier and mechanic. As IJN was not allowed to operate tanks the vehicle received the designation "Special Motor Launch" instead.

The vehicle was very different from the Type 95 Light Tank. Suspension and power transmission were similar but most parts were newly developed to cope with the weight. The rear idle wheel was relocated to the ground to increase ground contact. The springs and bell cranks were all mounted inside the vehicle to protect them from corrosion by sea water.

The armour scheme was completely different. Bow and rear armour were optimised for easy removal of the pontoons. All armour plates were flat and welded together. The lower bow armour consisted of two flat 12 mm armour plates with different negative angles. The upper part covered the tracks. Two clamps were mounted in the upper armour plate to fix the forward pontoon afloat. The upper bow armour was arranged sloped with both sides bent to the rear. A visor port for the driver was mounted on the (in driving direction) right side. In the center a third clamp for fixation of the pontoon was placed. On the left a standard MG mount was riveted to the armour plate. With the MG removed a detachable hemispherical cap covered the MG port watertight. Just before going ashore the cap was dropped off and the MG was mounted.

Image
frontal view

The side armour was arranged vertical. Flotation chambers were placed above the tracks on each side which also gives additional protection by the spaced armour effect. There was no access hatch for driver and bow gunner. On each side a ventilation air intake for the fighting compartment was mounted on the top armour next to the rear part of the turret. Both were covered with a hatch. Above the driver the steering cable for the rudders is starting. Several guide pulleys leads the cable to the rear along the right upper edge of the fighting compartment.

The turret was a modified version of the turret from the Type 98 Light Tank. It was slightly conical with a large hole for optical equipment on each side of the gun mount. A large semicircular hatch on the turret with a two-part lid allowed access. Armament consisted of a Type 98 37 mm Tank Gun and a coaxial Type 97 7,7 mm Tank MG mounted slightly offset to the left. A semicircular handrail was welded on the rear turret to make entering the tank afloat easier. A removable steering mechanism for the propellers and rudders was inside the turret. Afloat the commander steered the tank from there. The gunner left the turret during that phase.

The top armour of the engine compartment was arranged sloped to the rear. The side armour was slightly sloped, too. The side parts next to the engine compartment were arranged sloped with a much lower angle to simplify slipping of the rear pontoon when removing it. The rear armour had a nearly vertical upper part and a negatively angled lower part. Clamps on the armour on the side of the engine compartment and on the upper rear armour fixed the rear pontoon afloat.

The engine was mounted lengthwise in the rear. There was no separating steel plate between fighting compartment and engine making it quite loud inside the tank during movements. Three hatches in the rear top armour allowed access to the rear fighting compartment and the engine. The center hatch was the largest . It had a large air intake covered with a grid. The detachable air intake extension could be mounted on this grid using clamps and hooks. A rubber band on the armour plate made the connection watertight. The mesh-covered muffler was placed on the right side, the tail pipe was raised.

The ammunition supplier and the mechanic had their seats between turret and engine. The ammunition supplier had to help the commander by giving him the ammunition loaded inside the vehicle. He also moved MG ammunition from the transport racks to the bow gunner and gunner. The mechanic had to watch and maintain the complex machinery especially during operations afloat. During operations on land he was not really needed (repairs could be done faster by the maintenance units) and so not inside the tank most of the time.

Image
improved forward pontoon

The forward pontoon had a u-shape and was designed streamlined for an excellent driving quality. He had three flotation chambers with a total volume of 6,2 m³. The pontoon could be lifted by a collapsible jib boom (part of the equipment) over three hooks on the upper edge and two short handling rods on the lower part. With the pontoon attached the driver´s visor port was completely covered. A small recess allowed mounting the MG.

The rear pontoon was also u-shaped with the rear edges rounded. It was had three flotation chambers but only with a volume of 2,9 m³. The rudders were mounted under the pontoon on long axles which reached through the whole pontoon to the steering mechanism on top. Six hooks are mounted on the upper edge and two handling rods on the lower part for handling the pontoon with a jib boom.

Afloat the tank was operated from a small detachable conning tower mounted on the turret which could be easily detached. This was necessary as the view from inside the turret was too bad for navigation on the sea. The tower was conical with three visor ports next to each other in the forward part and three more mounted in each side and the rear. On top was a small access hatch. On the ocean the commander steered the rudders from inside the tower.

To prevent spray from the waves to get inside the engine a conical rectangular air intake with a wider cap could be mounted on the engine compartment. This was necessary in bad weather or heavier sea. It was made of simple steel plates and could also be removed easily.

Image
rear pontoon

The pontoons, the conning tower and the air intake extension were welded using 3,2 mm thick face-hardened armour plates. It was possible to transport both pontoons with a single Type 94 6X4 Truck. All parts necessary to get the tank ready for operation could be mounted by the crew within 15 minutes with the equipment of the tank.

Afloat two large screws next to the tracks moved the tank. The driving shafts were connected with the engine over a power dispensing devise which separates the two types of propulsion. This device was also responsible for sending power to the bilge pumps. The rudders were mounted on the rear pontoon.

The concept worked very well and so in mid 1942 the decision was made to start a serial production immediately. Official designation was "Special Type 2 Motor Launch". It seems that the popular short designation "Ka-Mi" wasn´t adopted officially but it was used by the units operating the vehicles. 300 vehicles were ordered. The first unit using this tank was formed in late 1942. There are few US reports of early version Type 2 armed with the Type 94 37 mm Tank Gun but there was no japanese source yet.

After the first exercises some changes were demanded by the soldiers. So a radio was added, the antenna base was welded on the rear right of the turret. The forward pontoon was remodeled to improve detaching. Therefore it was cut along the center line making it two-piece. The recess for the bow MG was widened to make the driver´s visor port accessible. The clamp in the upper bow armour was now surplus. A handrail was added to the pontoon. Other changes were made inside the tank to simplify handling. Most important was the installation of an onboard communication system with headphones to compensate the engine noise. The changes were adopted officially in summer 1943.

Only 184 vehicles were produced by Mitsubishi until surrender due to raw material shortages and a change in IJN strategy. They were issued to independent tank companies of the SNLF. Several units fought against US invasion forces in 1944 and 1945. Most spectacular was the attack of the 101st SNLF which swam from Luzon via Samar to Leyte during the US Invasion in late 1944. Due to the weak gun the success was limited. Nevertheless the US Army and Navy was impressed by the good seaworthiness which was far superiour to any other contemporary amphibious tank in the world. It was even possible to carry the tanks with submarines and launch them shortly below the surface.

Image
rear view

In western literature the first production version is sometimes designated "Type 1 Ka-Mi" or "Type 1 Ka-Sha" which is not correct. There was no change in the official designation.

There are still several Type 2 Ka-Mi rusting on different pacific islands. Only few are on display in Museums. A vehicle with both pontoons and the air intake extension can be seen at Kubinka Tank Museum near Moscow.

Data

vehicles built: 184
battle weight: 9,15 (metric) t, 12,5 t with floating equipment
crew: 5-6 men
length: 4800 mm, 7420 mm with pontoons
width: 2800 mm
height: 2300 mm
track width: 305 mm
engine: Mitsubishi A6120VD in-line 6-cylinder air-cooled Diesel engine
power: 115 hp at 1800 rpm
maximum speed: 37 km/h on roads, 9,5 km/h afloat
range: 320 km on roads 140 km afloat
transmisson: 8 forward, 2 reverse
armament: 1 X Type 98 37 mm Tank Gun , 2 X Type 97 7,7 mm Tank MG
Ammunition capacitiy: 132 37 mm grenades, 3900 MG shots




armour turret front
side
rear
roof
superstructure front
side
rear
roof
suspension front
side
rear
strength (mm)12 at 85°
12 at 85°
12 at 85°
6 at 0°
12
6 + 6
12
6
12
12
6




B) Special Type 3 Motor Launch

Image

After introduction of the Type 2 Ka-Mi SNLF demanded a similar vehicle with more armour and a 47 mm gun. The development of a successor was started in early 1943. Most data were lost after surrender. So many details are unknown.

Development was done in cooperation with Mitsubishi. To speed up the process many parts of the Type 1 Chi-He were used including the turret, the engine, suspension elements and parts of the transmission and steereing. Other elements were modified from the predecessor like the pontoons, steering and propulsion afloat and internal structure. But it was not developed from the Type 1 Chi-He as stated in many sources.

The hull was huge and bulky. Bow, side and rear armour were almost vertical making it easy to penetrate it. Only the upper front and side armour was arranged sloped. There were four access hatches to the flotation chambers in each side armour. Two clamps each in the bow and upper bow armour fixed the frontal pontoon. Driver´s visor port and bow MG were arranged as in the Type 2 Ka-Mi. The turret was placed in the center line. There were two pairs of ventilation hatches on the sides of the top armour, one between driver and turret and one next to the turret overhang. The cable for operating the rudders started on the right side in front of the turret. Number and location of the access hatches to the fighting and engine compartment are unknown. The air intake extention was mounted at the rear end of the engine compartment. So it can be assumed that the main engine access hatch was there, too. There was an exhaust pipe with muffler and raised tail pipe on each side of the vehicle´s rear top armour. Four clamps on the rear armour fixed the rear pontoon.

The suspension consisted of four pairs of roadwheels. Two pairs each were connected with bell cranks to a large vertical coil spring covered by a semicircular armour plate. The rear idle wheel protruded the vehicle completely. The frontal driving sprocket and four return rollers completed the suspension. All parts were mounted outside the vehicle.

Both pontoons were quite similar to the pontoons of the predecessor but they were larger to cope with the weight. The rear pontoon did not enclose the vehicle rear. It was completely behind the tank. A similar conning tower for the commander´s cupola and a similar air intake extension completetd the equipment for seaworthiness.

Image
vehicle without pontoons, general shape is correct but details can differ

Only the prototype and 19 pre-series vehicles were built in late 1944. It is unknown if the short designation "Ka-Chi" was adopted officially. The vehicles were only used for exercises. Some internet sources claim that there was a successful test launch from a submerged submarine from a depth of 100 m but I found no more reliable sources yet. There is no known survivor today.

The whole vehicle was far too large for the chosen armament and the armour scheme and strength would have made it an easy to destroy target.

Data

vehicles built: 20
battle weight: 28,25 (metric) t with floating equipment
crew: 5-6 men
length: 10300 mm with pontoons
width: 3000 mm
height: 3820 mm
engine: Mitsubishi Type 100 V-type 12-cylinder air-cooled Diesel engine
power: 240 hp at 2000 rpm
maximum speed: 32 km/h on roads, 10,5 km/h afloat
range: 320 km on roads 140 km afloat
transmisson: 8 forward, 2 reverse
armament: 1 X Type 1 47 mm Tank Gun , 2 X Type 97 7,7 mm Tank MG




armour turret front
side
rear
roof
superstructure front
side
rear
roof
suspension front
side
rear
strength (mm)2 X 25 at 78°
25 at 75°
25 at 90°
10 at 0°
50 at 78°
10 at 70°
10 at 90°
10 at 0°
50 at -85°
10 at 90°
10 at 90°




C) Special Type 4 Motor Launch

Image

After the Battle of Wake IJN decided to make a larger survey about the causes of the quite large losses. One main cause found was that the landing craft used were open to the top exposing the passengers to enemy small arm fire and especially splinters. In addition the armour was relatively weak making it easy to penetrate the sides and the bow with heavier weapons. This problem became urgent again during the 1942 Solomon Island campaigns. There landing crafts were often attacked by aircraft which shot into the cargo bay from above. As result the decision was made to develop a better protected landing craft for these kind of operations. Requirements were among others:

- easy to unload and load for transport ships
- usable on land and in the water
- closed cargo compartment
- armed with one or two Type 93 13,2 mm Machine Cannons for close defence


In 1943 the US presence was increased especially in the south and central pacific. This lead to increasing losses among transport and supply shippings because of submarines and long-range aircraft. Especially forward garrisons on smaller island were sometimes cut off from supply. So the landing craft should additionally be able to be transported and launched from submarines.

A prototype was finished in late 1943 at Kure Naval Yard. Operational tests were finished in March 1944. Crew consisted of driver, navigator, two gunners and a mechanic. The vehicle had a boat-shaped armoured hull with a maximum armour strength of 10 mm. Afloat the landing craft was powered by two propellers in the rear. Rudders were behind them for steering. For movenments on land a track suspension was added. The suspension was similar to the Type 98 Light Tank Ke-Ni. It consisted of four pairs of roadwheels connected with bogies. Each two pairs were connected by bell cranks with large horizontal coil springs. These elements were placed inside the vehicle for protection against corrosion by seawater. A forward driving sprocket, five return rollers and a rear idle wheel completed suspension.

The whole vehicle was covered by an armoured deck. Internal chambers on the bow and rear delivered additional buoyancy for stabilty. Crew and engine compartment was in the forward half. A driver and a navigator operated the landing craft from an armoured cabin with two visor ports on the bow. The rudders were operated over a cable mechanism similar to the Type 2 Ka-Mi. During the final approach to the shore the driver could change to a steering position on the deck behind the cabin. There he was protected by armour plates from the front and the sides. The rear was open for a better overview. A visor port was placed in the frontal plate. A Type 93 13,2 mm AA-Machine Cannon could be mounted on a pivot on each side of the steering position on deck.

The vehicle was powered by the Mitsubishi A 6120 1 in-line 6-cylinder Diesel engine, a modified version of the engine of theType 97 Medium Tank. The air intakes on deck were made water-tight with float valves. A long exhaust pipe lead to the rear mounted muffler with raised tail pipe. A cargo compartment was placed behind the engine compartment. Maximum payload was 4 t or up to 40 men (some of them on deck). It was possible to carry larger loads on deck but vehicles could not be carried. There were three watertight access hatches on the crew compartment and three more on the cargo compartment. Several hooks around the deck allowed easy loading and unloading from ships

During tests the vehicle was easy to steer but slow. Nevertheless the design was accepted under the designation "Special Type 4 Motor Launch". It is unclear if the short designation "Ka-Tsu" was introduced officially.

Image
Type 4 Ka-Tsu with cannons mounted and cargo on deck

In January and February 1944 US forces captured the central pacific atolls of Eniwetok, Kwajalein and Majuro. During the following months US-Navy expanded the already built japanese air and naval bases to a a large forward base for future operations against Truk and the Marianas (Saipan, Tinian, Guam). Japanese submarines and long-range reconnaissance aircraft delivered good reports about these works. So in April 1944 IJN started to plan a massive attack on these bases (Operation Yu-Go). Part of these plans was to launch special attack units using torpedo vehicles from submarines to attack anchorages. For this operation the vehicles should be used. This made several modifications necessary.

The exhaust pipes and the steering mechanism for the rudders were relocated below the deck. On each side a mount for a modified Type 91 Model 3 450 mm aircraft torpedo was welded on the deck above the fighting compartment (Many western sources claim that the torpedoes were Type 93 610 mm Long Lance but almost all japanese sources say Tpe 91 Model 3). A simple aiming device was mounted in the driver´s cabin. Special hooks to carry the vehicle with submarines were also added. To mount the torpedoes the machine cannons had to be removed. During the first trials the crew had problems to keep the vehicle watertight submerged. The air intakes finally had to be sealed with special coverages to prevent the engines from flooding but it took some 20 minutes to remove them and to make the vehicles ready to start. During this time the submarine had to stay at the surface. A submerged start as planned was not possible. Nevertheless IJN decided to introduce the vehicle with these changes. Production numbers are unknown but at least 50 vehicles were built.

Operation Yu-Go was cancelled in mid 1944 due to the fast US advance to the Marianas. The operating soldiers disliked the slow speed afloat but they had to use the vehicles because there was nothing similar avaliable. Crew training continued and until late 1944 800 soldiers were trained on these vehicles. In late 1944 operations against US ships at Luzon were planned but cancelled after a tanker destined for fuel supply was sunk during a convoy mission.

Some sources claim that the unit was used in 1945 to resupply cut-off pacific island garrisons. The plans for homeland defence included suicide torpedo attacks of the Type 4 Ka-Tsu on the invasion fleets.

Image
2 vehicles equipped with torpedoes carried by the B2-class submarine I-41

Most vehicles were scrapped postwar but at least one is on display at WWII and Korea LVT Museum, Camp Del Mar, Marine Corps Base Camp Pendleton, California, USA

Data

vehicles built: 50 or more
battle weight: 16 (metric) t
crew: 5 men
maximum armour: 10 mm
length: 11000 mm with pontoons
width: 3300 mm
height: 2250 mm to deck, 4050 mm maximum
engine: Mitsubishi A 6120 1 in-line 6-cylinder air-cooled Diesel engine
power: 120 hp at 2000 rpm
maximum speed: 20 km/h on roads, 8 km/h afloat
range: 300 km afloat
armament: 2 X Type 93 13,2 mm Machine Cannon or 2 X Type 91 Model 3 450 mm Torpedo



D) Special Type 5 Motor Launch

no picture, sorry
Image

There are only few informations about this vehicle avaliable. It is even not sure that the prototype was finished before surrender.

Upon the avaliable drawings (which differ largely in details) it can be assumed that the tank was a try to remodel the Type 3 Ka-Chi to make it less vulnerable against enemy fire. Size and shape are similar, most known data also fit for both vehicles. The most significant changes are a far better bullet deflecting armour scheme, a change in armament and different pontoons.

The upper bow armour was now sloped with a lower angle. The lower part was still negatively sloped but with a shallower angle. The superstructure armour wasn´t changed on front and sides. The rear armour was now similar to the Type 2 Ka-Mi.

The Type 1 47 mm Tank Gun was now mounted on the position of the bow MG. The MG was replaced to the right between gun and driver´s visor port. In the turret a modified Type 96 25 mm Machine Cannon replaced the gun.

The frontal pontoon was now flatter to allow using the bow armament during landing. The rear pontoon was shorter and had the shape of the rear pontoon of the Type 2 Ka-Mi.

Image
Scale model, details are surely different to the historical vehicle

Due to an error in the book "Tanks of the World 1915-1945", from Peter Chamberlain and Chris Ellis many internet sources show a picture of the Type 2 Ka-Mi without floating equipment as a picture of this tank. This is definitely wrong. There is no known picture of the Special Type 5 Motor Launch.

Data

vehicles built: 1
battle weight: 29,1 (metric) t
crew: 5-7 men
maximum armour: 50 mm
length: 10800 mm with pontoons
width: 3000 mm
height: 3380 mm
engine: Mitsubishi Type 100 V-type 12-cylinder air-cooled Diesel engine
power: 240 hp at 2000 rpm
armament: 1 X Type 1 47 mm Tank Gun, 1 X Type 96 25 mm Machine Cannon, 2 X Type 97 7,7 mm Tank MG




E) Short Barrel 120mm Gun Tank

Image

In late 1944 the SNLF demanded a gun tank similar to the IJA Type 2 Gun Tank Ho-I but with a larger gun for close support. So the decision was made to upgun the Type 97 Medium Tank KAI with the short 12 cm gun developed in 1942/43 for close defence of transport ships.

The hull of the tank was not changed. The gun mount was replaced by a massive mount with a large recoil mechanism. There were several recoil cylinders mounted around the barrel and covered with a round armour for protection. This recoil mechanism was still not able to cope with the recoil forces and so a flat muzzle break had to be added, too.

The gun was developed as high-angle multi purpose gun. It should provide close-range fire against aircraft , submarines and small attack boats. Due to the short barrel it was almost impossible to hit moving targets so only barrage fire was made. Data for the gun are:
- caliber: 120 mm
- gun length: 1510 mm
- bore length: 1440 mm (L/12)
- rifling length: 1127 mm
- grooves: 24 (1.0 mm x 11.78 mm)
- lands: 3,93 mm
- twist: Increasing RH 1 in 30 to 1 in 13
- weight: 2950 kg with mount
- chamber volume: 3 dm³
- muzzle velocity: 290 m/sec
- rate of fire: up to 15, 10 for continuous fire
- ammunition: HE, Incendary, Chemical, Anti-submarine
- grenade weight: HE 11,8 kg with a warhead of 2,5 kg and a propellant charge of 0,49 kg
- fuzes: time, impact, anti-submarine (time and/or preasure)
- maximum range: 5300 m
- maximum ceiling: 3100 m

Image
Drawing of the loading device

Maximum range was reduced due to the limited elevation of the gun mount. Due to the screw-type breech of the new gun the already low space inside the turret was reduced. In addition the ammunition was too heavy to be loaded inside the turret. Therefore a hole was made in the rear of the turret. The ammunition was loaded through the hole onto a loading cradle behind the gun. On each side of the hole an ammunition rack for two genades was mounted. During loading the loader was only protected by the turret. It is not known if there were additional ammunition racks inside the tank.

Further details are unknown.

Image
view on the open breech (on the left) through the commander´s cupola, note the handwheel for the Manual turret traverse mechanism in the lower right

An unknown number of Chi- HA KAI were modified this way in 1945. After surrender US units found at least 4 vehicles at Sasebo SNLF base and 10 more at Yokosuka SNLF base. All were scraped postwar.

Data
as Type 97 Medium Tank Chi-Ha KAI except:

vehicles built: at least 14
armament: 1 X Navy Short 12 cm Gun , 1 X Type 97 7,7 mm Tank MG



F) Long Barrel 120 mm Gun Tank

Image
only known picture

Informations on this vehicle are scarce. After surrender US forces found at least one vehicle at Yokosuka Naval Yard. It is unknown if it was a local conversion or an official development.

A Type Taisho 10 120 mm gun was mounted on the hull of a Type 97 Medium Tank. The turret was removed and the hole closed by steel plates. Additional steel plates were welded on each side of the fighting compartment to create a platform for the gun crew.

Data of the gun are:
- caliber: 120 mm
- gun length: 5600 mm mm
- bore length: 5400 mm (L/45)
- rifling length: 4649 mm
- grooves: 34 (1.45mm x 6.688 mm)
- lands: 4,4 mm
- twist: uniform RH 1 in 28
- weight: 218 kg without pivot
- chamber volume: 10,774 dm³
- muzzle velocity: HE 830 m/sec Illuminating 700 m/sec, anti-submarine 250 m/sec
- rate of fire: up to 11 per minute, 7 for continuous fire
- ammunition: HE, AP , Incendary Shrapnel (AA), Illuminating, Anti-submarine
- grenade weight: HE 34 kg with a warhead of 1,9 kg and a propellant charge of 5,5 kg
- fuzes: time, impact, anti-submarine (time and/or preasure)
- maximum range: 16000 m
- maximum ceiling: 10000 m

There are no further infos. Due to the gun weight and dimensions it can be assumed that the vehicle was top-heavy making it a quite unstable firing platform.


Yours

tom! ;)

tom!
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Re: The japanese armour and other vehicles thread

Postby tom! » Mon Jul 01, 2013 9:42 am

Hi.

18) Air Defence Vehicles

After World War 1 IJA also tried to develop air defence vehicles based on trucks. None of these was used operational. After introduction of the Type Taisho 11 7,5 cm AA-gun there were trials to mount it on the heavy Army 4t Prime Mover truck. There is also no record of an operational use. Until late 1930th there were no further special developments but during the operations in Manchuria and northern China improvised AA-trucks using Type 88 7,5 cm AA-guns and Type 93 13.2 mm Machine Cannons were used. In the mid 1930th first trials to mount light AA-guns on tracked vehicles.


A) Prototype anti-aircraft tank No. 1 Ki-To

Image

In 1938 the Type 97 Light Armoured Vehicle Te-Ke was modified to be used as gun platform (see Experimental 3,7 cm Gun Carrier So-To). At least two prototypes were equipped with the Type 98 2 cm Automatic Gun and tested. The guns were mounted on the gun platform with the tripod lafette. The two wheels were carried on the rear of the vehicle.

Data of the gun are:
- caliber: 20 mm
- barrel length: 1400 mm (L/70)
- ammunition: 20 mm X 142 mm HE-T self-destroying, AP-T; fed by 20 shot magazines
- weight: 373 kg with wheels
- traverse: 360°
- elevation: -5° to 85°
- muzzle velocity: 830 m/sec
- range: 5500 m
- ceiling: 3500 m
-rate of fire: 300 rounds/min theoretical, 120 rounds/min practical
-carriage: two wheel split trail with supporting leg

Image
vehicle during trials, note the second vehicle in the back

The project was cancelled due to the missing crew protection and the limited space for the crew. The fate of the prototypes in unknown. The short designation "Ki-To" means "2 (cm) gun carrier.

Data

unknown



B) Type 98 2 cm Automatic Gun on Type 94 6-wheel Automatic Truck

Image

In 1940 IJA decided to develop a standard specification how to mount the Type 98 2 cm Gun on the load bed of the Type 94 Truck wich was the standard towing vehicle for this weapon. The gun was mounted with the split trail and supports on the wheel axle. The supporting leg was not used to spare space. Wheels and leg were carried on the vehicle behind the cabin. The gun could easily be converted for ground use. To receive a larger operating platform for stationary use each loading flap was equiped with four telescopic supports.

This configuration became standard in the air defence units of the tank divisions.

Data
as Type 94 6-wheeled Automatic Truck



C) A) Prototype anti-aircraft tank No. 2 Ta-Se

Image

In March 1941 IJA started the development of a new anti-aircraft tank with a better protection than the Ki-To. A prototype was finished in November 1941.

The vehicle was based on the Type 98 Light Tank Ke-Ni. The first prototype had an unchanged hull. The turret was replaced by an open top cylindrical turret with a large rear overhang. The overhang was not accessible from the cylindrical inner turret. Six magazines cound be loaded there. A large hatch on top allowed access. A Type 98 2 cm Automatic Gun with recoil mechanism was mounted. A simple optical sight with three possible speed adjustments (300 km/h, 500 km/h, 700 km/h) allowed an effective range of 1000 m. Elevation was -5° to 80°, traverse 15 ° to each side. For a traverse of 360° the turret had to be turned manually by the gunner. Gunner and commander completed the crew. An external loader was assigned if necessary.

During innitial tests the gun performance was found weak. So the gun was replaced by an experimental version with a longer (L/100) barrel made during development of the Type 1 2 cm Automatic Gun (which used the mount of the german 2 cm Flak 30). With this gun an effective range of 1400 m could be reached. In addition the hull was remodelled to increase crew space and ammunition capacity. The side armour was replaced by vertical armour plates and the top armour was enlarged. The turret top could now be covered with a canvas.

Image
early version

Tests with the modified vehicles were made in March 1943. Operating the gun was quite problematic with a one-man-turret. The low weight of the vehicle and the hight turret also made it instable during firing. In addition the manual turret traverse and the optics made following fast flying targets impossible. Therefore the project was cancelled in 1944.

The short designation "Ta-Se" is short for "Anti-aircraft tank".

Data:
as Type 98 Light Tank Ke-Ni except

- height: around 2800 mm
- armament: 1 X Type 98 2 cm Automatic Cannon, later 1 X Ho Ki Type II Experimental 2 cm Automatic Cannon



D) Type 98 2 cm Automatic Gun on Type 98 Halftracked Prime Mover Ki-Ho

Image

In 1944 the air defence units of the tank divisions also used a Type 98 2 cm Cannon mounted on the Type 98 Halftrack Ki-Ho. The vehicle was modified similar to the Type 94 Trucks. Due to the halftrack suspension mobility was increased. On the other hand the load bed was smaller limiting the size of the gun platform. Wheels and third leg of the gun couldn´t be transported on the vehicle. The conversion was time consuming as the gun crew seats and equipment racks of the basic vehicle had to be removed.

It is unknown if the configuration was adopted officially or if it is just a field conversion.

Data:
as Type 98 Halftracked Prime Mover Ki-Ho



C) E) Prototype anti-aircraft tank No. 3 So-Ki

Image

In mid 1943 the development of an improved version of the AA-tank Ta-Se was started. The vehicle was also based on the Type 98 Light Tank Ke-Ni.

The Ke-Ni was remodeled massively. The complete superstructure and the turret were removed. The new superstructure had a similar shape but was larger. The Crew compartment was extended over the tracks to get more space for ammunition. Behind the driver a platform for the gun was added. The forward superstructure was higher than the platform to provide additional protection for the lower part of the lafette. In addition an armour plate was welded on the forward edge of the driver´s cabin. side and rear armour were arranged vertical. On the rear of the platform a bench for the crew was mounted. The seating surface could be opened and allowing access to an ammunition rack for at least 12 magazines. A standard Type 1 2 cm Automatic Cannon including gun shield was mounted on the gun platform.

Trials started in March 1944. The vehicle tests were successful but the power of the gun was rated too weak for such a vehicle. So in mid 1944 the gun was replaced by a Type 2 2 cm Automatic Gun which had two barrels. A gun shield had to be developed as the Type 2 had no shield.

Image
late version

The vehicle was not adopted because the 2 cm caliber was already too weak against contemporary aircraft. A similar design based on the Type 1 Tracked APC Ho-Ki was also cancelled. Mounting a larger gun was impossible due to the weight limitations of the suspension. Due to the critical situation the whole program was cancelled. Further details are unknown.

Data:
as Type 98 Light Tank Ke-Ni except

- height: around 2800 mm
- armament: 1 X Type 1 2 cm Automatic Cannon, later 1 X Type 2 2 cm Automatic Cannon


Yours

tom! ;)

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Re: The japanese armour and other vehicles thread

Postby Ricky » Tue Jul 02, 2013 8:44 am

I'm always ipressed by the full range of specialist vehicles the Japanese developed.

I'm also very curious/impressed that their amphibious AFVs could be submarine launched. Did the vehicle crews/passengers stay in the AFV during the voyage?
"Study the past, if you would divine the future"
-Confucius

"I am pedantic, I'm just being overshadowed by Ricky so it isn't as noticable as it would else have been"
-Skua

tom!
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Re: The japanese armour and other vehicles thread

Postby tom! » Tue Jul 02, 2013 10:18 am

Hi.

There was no possibility to enter the vehicles from the submarines. So the crew had to stay in the tank. And it was impossible to start the engine submerged. So the standard procedure was to start the tanks surfaced. Submerged starts were just trials.

Yours

tom! ;)

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Re: The japanese armour and other vehicles thread

Postby tom! » Tue Jul 02, 2013 10:19 am

Hi.

19) Special Purpose Engineer Vehicles

As many other armies of World War 2 IJA used a variety of tracked special purpose vehicles for various duties. Especially the engineer units received many different vehicles.

IJA had eight differently specialised types of engineer units:
- Type A: Combat engineers (direct infantry support)
- Type B: Tunnel building
- Type C: Bridge and pier building (permanent constructions)
- Type D: Shipping (operates landing craft and coordinates loading and unloading of troops and supply)
- Type E: River crossing (special unit for Type 95 Collapsible Boats)
- Type F: Fortification assault 1 (using manned charge layers)
- Type G: Bridge building support (later merged with Type C)
- Type H: Fortification assault 2 (using unmanned charge layers)

Each engineer company was specialised in one of these types. There were special tracked vehicles for Type A, Type E, Type F and Type H units. Type F units were reorganised in 1940 as mechanised engineers to support armoured units. After merging Types C and G, Type H as renamed Type G.

Base and airfield building was done by specialised independent Base or Airfield Construction Units. These were army-level units and not rated as engineers. Railway engineers were part of special railway units.


A) Nagayama Tank

Image

In 1929 engineer corps Major Nagayama suggested to use unmanned, radio-controlled vehicles for dangerous tasks like mine clearing and charge laying. Until early 1930 a Fordson Model F tracked prime mover was reworked as lightly armoured vehicle. The tractor was covered with face-hardened armour plates able to defeat infantry AP ammunition. The 20 hp gasoline engine was placed in the center. The steering mechanism was placed in the forward part. On the rear a payload container e. g. for ammunition or an explosive charge could be mounted.

The radio equipment was mounted in a superstructure in the center of the vehicle. The control orders were transmitted by a modified infantry radio powered by lead accumulators. Two antennas on the superstructure received and transmitted data. Further details are unknown.

Image
control equipment, note the large number of accumulators

In late February 1930 a public demonstration was made at Tokyo Army Arsenal. The tank was a sensation in european and US newspapers. The development was discontinued most likely due to the limited mobility of the suspension but the basic idea was rated useful. The fate of the prototype is unknown.

Data:
unknown



B) Armoured Working Vehicle SS

Image

In 1929 IJA started to work on the total occupation of Manchuria. The Soviet Union also had an eye on that region and already started to build field fortifications at the border. Therefore Army Engineer Division Department II was ordered to develop an armoured vehicle able to destroy pillboxes and obstacles. In 1930 prototype production started in cooperation with Mitsubishi. It was designed as multi-purpose vehicle able to do much more than requested. Up to 9 different tasks could be done with it:

- obstacle removing
- mine clearing
- charge laying
- flamethrowing
- poison gas spraying
- disinfection agent spraying
- crane operation
- trench digging
- smoke screen laying

In June 1931 the prototype was finished. The vehicle used parts of the Type 89 Medium Tank suspension, transmission and steering but it was not developed from the Type 89 as stated in many sources. The suspension consisted of eight roadwheels, each 4 combined, four return rollers, a large frontal driving sprocket and a large rear idle wheel. The leaf spring packages and return rollers were covered by a two part trapezoid 6 mm armour plate.

Image
Version Kou(A)

The bow was stepped. On the lower bow armour were several attachment hooks for different types of equipment like a wedge made of steel sections for obstacle removing or an explosive charge container. On each mudguard a headlight coverable with a hemispherical cap was mounted. The forward superstructure was slightly sloped with the outer parts bend to the rear. The driver sat on the (in driving direction) right side behind a visor port. In the center a mount for a removable flamethrower nozzle was implemented. Above this position a flat conical commander´s cupola with an access hatch was placed. On the left side a standard MG port for a Type 91 6,5 mm Tank MG was mounted.

The side armour was vertical. In the forward half trapezoid armour extension were over the tracks on each side. A flamethrower nozzle mount was in each forward side armour. In the vertical rear armour was a large rectangular indentation. A trench digging plow or large steel tanks for flame oil or chemical agents could be mounted there. The top armour was slightly sloped to each side and the rear but horizontal in the center. Hatches on each side of the crew compartment allowed access to. A 5 t crane could be mounted between these hatches on the crew compartment. The engine was mounted lengthwise in the rear. A large hatch with air intake grills in the top armour allowed access. The muffler was placed on the upper rear armour.

During tests several changes were demanded. The suspension armour was replaced by a single trapezoid plate over the springs to spare weight. The conical commander´s cupola was replaced by a larger hemispherical cupola without hatch. The muffler was replaced to the rear right mudguard and the whole mudguard was covered by a wire mesh. Several other changes were made regarding internal elements.

In 1933 operational tests were made at Engineer Corps School. Until mid 1934 12 more vehicles were built for test purposes. A 9 m scissor bridge to be mounted on the top armour was developed, too. After finishing the tests the vehicle was officially adopted as "Type 96 Armoured Plow" in early 1936. Th
e Type 96 Model 4 radio set was chosen as wireless equipment.

Image
Version Otsu with scissor bridge, crane and driving sprocket of version Tei

The first modification started shortly after introduction. To allow use of the flamethrowers and other chemical agents parallel small flame oil tanks were mounted between the suspension parts. The armour plate had to be removed to gather the necessary space. The fourth return roller was also removed. In addition driving sprocket and idle wheel changed place. This allowed a much shorter bow as the major transmission elements were also replaced to the rear. The step in the frontal armour was replaced by a single sloped plate with attachment points. A special mine fork could be mounted on each side. The hemispherical commander´s cupola was replaced by a rectangular cupola with sloped sides and hatch. The engine was moved forward and arranged sidewise. The widened forward side armour was lengthened to cover the engine compartment, too. The rear armour was raised to gather space for the transmission. All transmission and steering elements were accessible through a driver´s and maintenance compartment in the rear. A second smaller conical cupola above this compartment allowed a better observation of the battlefield. For better protection the steel tank in the rear was replaced by a rectangular concrete tank. This new version was adopted under the designation "Armoured Working vehicle Version Otsu" in 1937, the first version received the additional designation "Version Kou(A)" The original designation was dropped. Eight vehicles of version Otsu were produced in 1937.

In late 1937 a fourteenth vehicle of version Kou(A) was built with several modifications. A 120 hp Diesel engine replaced the gasoline engine. A second muffler was added on the rear left mudguard. The suspension armour was enlarged with five steel plates above the return rollers to an armour scheme similar to the prototype. The flamethrower mounts in the forward side armour were replaced in the side armour of the fighting compartment. The special nozzles were replaced by standard Type 93 flamethrower nozzles. This version was adopted as version Hei but not produced.

Image
Version Hei

In 1939 a fourth version based on version Otsu was developed. Driving sprocket and idle wheel were simplified reducing the weight. The frontal flamethrower mount and the MG port changed place. The rectangular commander´s cupola was replaced by a cylindrical cupola with a two-door hatch. The rear cupola was removed. The lengthened side armour extension were taken over from version Hei but a 150 hp Diesel engine was used. There was only one muffler on the left rear mudguard. A steel tank was used for the chemical agents again. This version was adopted as version Tei and 20 vehicles were built in 1939 and 1940.

In 1940 the operational experiences made during the China Incident were discussed. The vehicle did not really cover all projected tasks. It did a good job as mineclearer, bridgelayer, chargelayer and flamethrowing vehicle. Chemical warfare was done by units equipped with Type 94 Special Tractors and their chemical warfare trailers. Smoke screens were laid easier manually by infantry and combat engineers or using artillery grenades. So this tasks could be removed. For trench digging the engine has been proven too weak. The crane was also not longer needed as there were enough truck-mounted cranes. The mine plow was enough to remove wire obstacles. For heavier obstacles the engine was too weak, too. So the decision was made to reduce the tasks of this vehicle in a new version based on version Tei. This vehicle should be specialised on chargelaying and support of armoured units. A new easy to operate straight bridge should replace the scissor bridge.

Image
Version Tei

Development was finished in late 1940. The flame oil tanks between the suspension and the large rear tank were removed. Instead three standard Type 93 Flamethrowers including the flame oil and pressure tanks were used. One return roller was removed, too. The armour was now completely welded. Two additional flamethrower mounts were added in the forward side armour. On the lower bow armour a large access hatch was added between the attachment points. A new 145 hp Diesel engine was used. There was a muffler on each rear mudguard. The original hatches on the top armour were blocked by the new 7 m bridge. This bridge was carried on three rollers on each side and a support with two more rollers above the bow armour. It was laid from inside the tank by pulling a cable. A set of pulleys increased the force accelerating the bridge forward. Minimum range between vehicle and contact point was 2 m, maximum range 2,4 m. The bridge was carried in two parts on Type 94 6-wheled Trucks. It could be loaded on the tank using the acceleration cable directly from the truck or from the ground by a separate crane or using a step in the ground of at least 600 mm. The vehicle was adopted as version Bo in late 1940.

In mid 1942 the available vehicles were organised in three engineer regiments. 5th Independent Engineer regiment, stationed in Manchuria, had the order to attack soviet fortifications in case of an attack using the vehicles as manned charge layers. The other two regiments were assigned to 1st and 2nd Tank Division as divisional units. Their task was to support the tank regiments using the vehicles as mineclearers and bridgelayers. After raising 3rd and 4th tank regiment also received engineer regiments. nominal strength was 24 Armoured Working Vehicles per regiment but production numbers did not reach the necessary height. 2nd Tank Division had only 20 before the invasion of Luzon started. Only 77 vehicles of version Bo were finished until production was stopped in late 1944.

Image
Version Bo

The vehicles were useful as chargelayers and bridgelayers. The early versions had engine problems lowering endurance and possible tasks. US forces captured several of them on Luzon. Others were handed over at surrender in China and Japan. There is no known survivor.

The vehicle is also known under the short designation "SS-Ki" which is wrong. Japanese sources only use "SS."

Data (version Bo)

vehicles built: 77, total production 119
battle weight: 13 (metric) t empty, 16 t fully loaded
crew: 5 men
length: 4865 mm
width: 2520 mm
height: 2088 mm without bridge
engine: 6-cylinder air-cooled Diesel engine
power: 145 hp at 1800 rpm
maximum speed: 37 km/h on roads
range: 400 km on roads
armament: 1 X Type 97 7,7 mm Tank MG, 3 X Type 93 Flamethrower




armour superstructure front
side
rear
roof
suspension front
side
rear
strength (mm)25
16
10
6
25
6 + 6
10




C) Remote-Controlled Type 94 Special Tractor TK

no picture, sorry

After the tests and trials with the Nagayama Tank were finished in the early 1930th the decision was made to continue development using a Type 94 Special Tractor in 1935. The conversion of the prototype was done fast and first tests were successful. So the decision was made to convert at least a second vehicle for operational tests. Further data are unknown. In 1936 the vehicles were reconverted to the standard configuration. The concept of a radio-controlled vehicle was also abandoned in favour of remote-controlled vehicles using electrical commands transmitted by cables.

Data

unknown



D) Type 98 Miniature Engineer Vehicle Ya-I-Go

Image

In 1932 Scientific Research Section No. 1 of Army Technical Bureau proposed the development of a remote-controlled tracked vehicle to fight enemy pillboxes and fortifications by laying explosive charges. Control orders should be send to the vehicle through a multipolar cable. The charge should be jettisoned close to the target. Then a 30 second delay was started firing the charge. During the delay time the vehicle and the command tank should leave the blast radius. The Type 89 Medium Tank should be used as basis for the carrier and the command tank. The first design did not reach the prototype stage due to mechanical and electrical problems.

In 1933 the concept was still rated good and a second development program was started on a wider base. But instead of a large tank a small electrically powered tracked vehicle should be developed. Works started in late 1933. The vehicle frame was made out of a light-weight but very stable Aluminium-Silicon alloy. Suspension consisted of two pairs of small roadwheels, a fifth raised forward roadwheel to increase cross-country maneuverability, a forward idle wheel, a rear driving sprocket and two return rollers. Tracks with 87 links were usedTwo watertight 600 V electrical engines delivering 1 hp each were placed in the rear half inside the frame. Each engine powered one of the tracks. The control/power cable reached the vehicle from the rear. A barrel with a cone on its end was mounted on the vehicle as strain relief. On the bow was a metal box for the explosive charge. The cable had 13 wires, two for power supply and 11 for control commands. It was covered by a layer of rubber and hamp fabric. For an easier transport cable segments of 250 m length were used which could be connected. Maximum allowed length of a connected cable was 500 m on even ground. Cross-country only one cable segment should be used. The total height was just 460 mm, length 1425 mm. With a 35 kg charge the total weight was below 200 kg. On roads up to 18 km/h were reached, 4 km/h cross-country.

During first tests in 1935 the vehicle worked very well. Nevertheless several changes were done. The cable was additionally surrounded by a dense wire mesh for additional stability and protection against splinters. This allowed to use cables with up to four segments increasing the maximum range to 1000 m. Cross-country the range should not exceed 750 m. The charge was rated too weak against pillboxes. So a charge of 40 kg using stronger explosives was developed. The metal box on the bow was removed and the charge was mounted directly on the bow. In addition a Bangalore-type charge with a length of 1075 mm and a 2,7 kg charge was developed to be used against wire entanglements and obstacles. Additional mounts for smoke canisters were added on the vehicle. This vehicle was introduced in 1937 under the designation "Type 97 Miniature Engineer Vehicle" and received the short designation "I-Go"

The 40 kg charge was still too weak against thicker bunker walls. So the decision was made to develop a larger version, too. It used the similar basic scheme but the roadwheels were bigger. In addition two 2 hp engines were used to cope with the total weight of 400 kg. A charge of up to 300 kg could be carried. An improved Bangalore-type charge with a length of 1151 mm and a 3,2 kg charge was introduced, too. In addition low-power shaped-charge warheads for these charges with a penetration of 30 mm steel and 110 mm concrete were also developed. This vehicle was introduced in 1938. The official designation of both vehicles was changed to "Type 98 Mini Engineer Vehicle", short designation became "Ya-I-Go". The small vehicle received the additional designation "Version Kou(A)", the bigger one "Version Otsu".

Image
rear view, the upright stick on the rear is the body of a Bangalore charge.

The first unit using this vehicles was raised in early 1939 and stationed in Manchuria. A squad consisted of 12 men which operated a vehicle, a second was held in reserve. Besides the charge layers equipment consisted of a generator vehicle based on the Type 94 6-wheel Truck and several standard Type 94 Trucks for vehicle and equipment transport. For version Otsu a special armour shield made of 5 mm face-hardened steel was introduced to allow carrying a human observer under protection. An auxiliary generator vehicle based on version Otsu for heavy terrain was developed, too. This was replaced in 1943 by a generator vehicle based on the Type 98 Transport Tank So-Da. A standard attack was done by three squads. The first blows wire entanglements with the version Ko, the second destroyed obstacles with the version Ko and the third finally destroyed the bunker with a version Otsu. Standard starting position was between 200 m and 500 m away from the target. During exercises ranges up to 1500 m in easy terrain were reached. Larger ranges caused a current drop due to the cable resistance stopping the engines.

In 1940 the units stationed in Manchuria were combined to 27th Independent Engineer Regiment. The nominal strength was around 2000 men operating 108 chargelayers of both versions. The rest of the 300 production vehicles was stored in Japan for homeland defense. In April 1945 27th Independent Engineer Regiment was relocated to Honshu for the expected homeland decisive battle. At surrender the unit sunk their vehicles in rivers and lakes. The others were destroyed, too. There is no known survivor.

There were also versions tested for attacks on targets in the water and with larger charges towed behind the vehicle. None was introduced.

Data (Ko/Otsu)

vehicles built: 300
battle weight: 200 kg / 400 kg
crew: unmanned, one person could be carried with version Otsu
length: 1425 mm / 1980 mm
width: 635 mm / 1170 mm
height: 460 mm / 560 mm
trench crossing capability: 850 mm / 1100 mm
climbing capability: 40° / 30°
engine: 2 X 600 V electrical
power: 1 hp at 2000 rpm /2 hp at 2000 rpm
maximum speed: 18 km/h on roads, 4 km/h cross-country
range: 1500 m on roads, 1000 m cross-country
armament: 1 x 40 kg charge or Bangalore torpedo with 2,7 - 3,2 kg explosive / 1 X up to 300 kg charge




E) Experimental Armoured Bridgelayer TG

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In 1943 a couple of new developments of engineer tanks based on the Type 97 Medium Tank Chi-Ha were made.

The Armoured Working Vehicle SS version Bo had a similar speed on roads but the cross-country speed and maneuverability were inferior. So a new bridgelayer for the 7 m straight bridge was developed. The hull seemed to be remodeled largely. Available pictures in literature are showing no rivets on the armour. It looks like the armour plates were welded instead of riveted. The forward mudguards were lengthened to the size of the Type 1 Chi-He. The turret was removed and a steel plate covered the hole. A Chi-Ha commander´s cupola was mounted on the fighting compartment. The bridge was mounted in a similar way as on the SS. The support was strengthened and a framework falling from the support for easier load the laid bridge from the ground was added.

There were also tests with a rocket propelled bridge. It used four 610 mm solid fuel rockets with 1030 g propellant delivering a thrust of 420 kg/cm² for 0,5 seconds. It made range of 10, 8 m possible.

The vehicle was cancelled due to the lack of ressources.

Data

unknown



F) Experimental Armoured Minesweeper GS

no picture, sorry.
Image

A different approach to sweep mines was to use explosive ropes fired with small rockets. A Type 97 Medium Tank was equipped with a launcher for 8 rockets in 1943. Data for the rockets are unknown.
Below the wire-made launching tubes sealed boxes with explosive ropes were mounted. The rope was attached to the rocket and flew over wire entanglements and minefields and then detonated destroying the obstacle or exploding the mines.

With the launching pad installed on the engine room behind the turret the rear turret armament couldn´t be installed. So the decision was made to remove the main gun and turn the turret. A muzzle-loaded launcher for a small spigot-mounted Charge for obstacle demolition was installed in the rear turret MG mount which now faced forward.

The development was discontinued.

Data
as Type 97 Medium Tank Chi-Ha except armament as described



G)High-Voltage Dynamo Vehicle Ka-Ha

Image
only known picture

During the operations in China disturbing enemy communication was a key to success. Around 1940 the use of high current against wire-based communication was tested successfully. Tests were made with 200 V, 3000 V, 5000 V and 10000 V. The current destroyed equipment and also injured or even killed the operators in front of the telephones or telegraphs. So the decision was made to built a special vehicle for anti-communication warfare.

A Type 97 Medium Tank Chi-Ha was modified to carry a 10000 V Diesel generator. Such a vehicle was needed to cope with the weight. The turret was removed. Due to the size of the generator the fighting compartment had to be heightened. For camouflage the extension was similar shaped as the superstructure. A small turret with a wooden dummy gun and a handrail antenna dummy was added. On longer ranges the tank could be taken for a standard Chi-Ha.

The tank was driven to a telephone or telegraph line. A copper wire was connected to the communication cable. Then a metal anchor for earthing was hammerd in the ground near the tank to close the electric circuit. The charge was unloaded. Tests showed that the system worked but due to the dangers using high voltage the crew had to be very well trained.

Four Ka-Ha were built and issued to 27th Independent Engineer Regiment in Manchuria. There is no report of an operational use. All vehicles were destroyed.

Data

unknown



H)Experimental Trench Excavator

Image

The performance of the Armoured Engineer Vehicle SS with the trench digging plow were unsatisfactory. So after introduction of the Type 97 Medium Tank Chi-Ha the decision was made to develop a special trench digging vehicle from it.

The vehicle was largely modified. The superstructure was replaced by a shorter crew cabin. Two large visor ports with hatches opening to the top were mounted in the frontal armour. Between the was a smaller hatch covering a pistol port. Additional covered pistol ports were in each forward side armour. A turret from the Type 94 Special Tractor TK armed with a Type 97 7,7 mm Tank MG was mounted on the (in driving direction) left side. On the right side an access hatch was placed above the driver in the top armour. Due to the shorter crew compartment the engine could be shifted forward. Therefore the rear roadwheel could be removed. To increase ground contact length the rear idle wheel was relocated to the ground. On the back a large trench digging plow was mounted.

Image
vehicle during tests in Manchuria

First tests with the vehicle were made in late 1939 in Manchuria. Results are unknown but it can be assumed that they were also unsatisfying as there was no adoption of the concept. The Prototype was found abandonned with the suspension half burried in the sand by australian units on a beach on Wewak in 1945.

There is a nice photo series of the vehicle at the Australian War Museum online archive.

Data

unknown



I)Type 4 Work Vehicle

Image

One of the experiences of the Great East Asian War was that wheeled generator vehicles used to power larger electric machinery like well drillers, chainsaws, pumps, jackhammers etc. had problems with the muddy Terrain in the jungle. So in 1943 Army Engineer Division Department II started the development of a tracked power supply vehicle based on the Type 2 Light Tank Ke-To. The rear superstructure was heightened for a 30 KW Diesel generator. In Addition the turret was replaced by a smaller cylindrical turret with a frontal extension for a standard MG Mount and a light handling crane on the rear. Several large tool boxes were added on both mudguards and on the bow. A large illumination spotlight was mounted on a mast on the turet for night works. The prototype was finished and tested soon after development start

Image
prototype

A total of 25 vehicles were built but not issued. Instead it was decided to rebuild the vehicles as multi-purpose vehicle. Therefore the superstructure was completely removed and replaced by a 2-seat cabin on front, a 30 kW generator under face-hardened armor and a load bed on the rear. The turret was replaced by a larger crane. A dozer blade was added on the bow. It was handled with the crane. The reworked vehicles were mainly issued to airfield construction battalions.

No further infos.



Changes and additions:

04.11.2014
- Picture of bridgelayer TG added, a not too good pic is better than none
- Type 4 Work Vehicle added

Yours

tom! ;)
Last edited by tom! on Tue Nov 04, 2014 7:27 pm, edited 3 times in total.

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Re: The japanese armour and other vehicles thread

Postby tom! » Fri Jul 05, 2013 10:09 am

20) Special Purpose Construction Vehicles

As other armies IJA and IJN used civil earthmovers and specially developed vehicles for airfield and base construction. Here only the special developments are covered.

A)Armoured Lumberjack No. 1

Image

In eastern Manchuria large woodlands hampered the construction of fortifications, roads and airfields. So in late 1939 IJA decided to develop a special tracked vehicle with a ramming wedge on the bow to knock down trees up to 20 cm diameter. To allow usage near the enemy lines the vehicle should be armoured. A prototype was built at the automotive factory of Tokyo Gas and Electric Company (TGE, aka Gasuden) until early 1941.

The basic scheme was similar to the Armoured Engineer Vehicle SS but it was a completely independent development. The suspension was a mixture between the TGE standard suspension used on earlier developments and the Type 97 Medium tank. It consisted of eight roadwheels, a frontal driving sprocket, a rear idle wheel and five return rollers. Each 4 roadwheels were connected with a bogie and spring-mounted with leaf spring packages. Driving sprocket and idle wheel were taken from the Type 97 Chi-Ha. The armour plates were all welded. Bow armour and superstructure were arranged sloped. The ramming wedge was triangular with a dented front. It consisted of face-hardened steel plates welded together. The lower parts were curved inward. A hydraulics allowed a limited elevation. An access hatch for maintenance was in the top plate. Further details are unknown.

During tests the concept was rated useful but the vehicle did not really satisfy army officials. So the decision was made to develop an improved version.

Data

unknown



B)Armoured Lumberjack Ho-K

Image

Mitsubishi was ordered to develop the better lumberjack vehicle. They decided to use the Type 1 Chi-He as basis. But the complete superstructure and rear armour was remodeled from the Armoured Lumberjack No. 1. The fighting compartment was replaced by a similar shaped but higher crew compartment. In the frontal armour were two hatches opening to the top with viewports for driver and commander. Additional smaller viewport were mounted in the forward part of the side armour On the (in driving direction) left side was an equipment container accessible from outside the vehicle through a large hatch in the side armour. Three access hatches were in the top armour.

A Mitsubishi Type 100 12-cylinder air-cooled Diesel engine was placed lengthwise in the rear. Several hatches in the top armour allowed access. The air intakes were covered with steel plates to prevent sucking in larger wood splinters. Additional filters were mounted for smaller splinters. The mufflers were completely covered by hinged armour plates with cooling air intakes.

The prototype was finished in 1943 and tested in Manchuria with good success. 5 more vehicles were produced in 1943. At least one was tested in New Guinea. Further data are unknown.

Data
vehicles built: 6
battle weight: 15 (metric) t
crew: 5 men
length: 7480 mm
width: 2700 mm
height: 1800 mm
ground clearance: 400 mm
engine: Type 100 12-cylinder air-cooled Diesel engine
power: 240 hp at 2000 rpm
maximum speed: 39 km/h on roads




C) Lumber Sweeper Basso-Ki

Due to the lack of a scanner no picture, sorry

The development program of the Armoured Lumberjack No. 1 also included a special vehicle to remove the knocked down trees. For this purpose TGE developed a special tracked crane vehicle. The suspension was taken from earlier projects. It consisted of eight roadwheels, a rear driving sprocket, a frontal idle wheel and four return rollers. Each 4 roadwheels were connected with a bogie and spring-mounted with leaf spring packages. The return rollers were arranged paired but not connected. On the bow two cranes were mounted, one on each side. The capacity is unknown. In the center was an open top driver´s compartment. The engine was mounted lengthwise in the rear.

It was planned to use two of these vehicles and one lumberjack as team. The knocked down trees were hoisted with the cranes and moved to the side. Trial results and production numbers are unknown, Due to the low number of lumberjacks it can be assumed that the number of sweepers was low, too.

Image
later prototype vehicle with new suspension

In 1943 the vehicle was redesigned. Now the Experimental Prime Mover Chi-Ke was used as basic vehicle. it used the standard suspension of the Type 97 Medium tank minus the rear roadwheel. A cabin for the driver was mounted directly behind the cranes now. No further info available.

Data

unknown



D)Armoured Dozer

Image
Serial production vehicle, dozer blade attached to the turret

During the 1930th and the early 1940th IJA used Komatsu designed (civil) bulldozers for airfield construction. In 1943 the decision was made to develop a special dozer based on the Type 97 Medium Tank Chi-Ha KAI to standardise spare parts and to increase mobility. Mitsubishi was ordered to do the design works. The protoype used a dozer blade mounted on the first roadwheel. It should be operated by a hydraulic system using two large cylinders mounted on the bow armor. The needed pumps couldn´t be mounted in the tank due to the limited space. Therefore they were placed on the outside on the left side of the turret making it impossible to turn it. This design was rejected mainly because of the vulnerability of pump and cylinders and the lack of production ressources for the components of the hydraulics. The loss of turret traverse and the operation of the system from outside the tank were not found problematic as it wasn´t planned to use the tanks for frontline duties.

Image
prototype

Until February 1944 the design was changed. Now the dozer blade was mounted on the tank by wires. It was operated by hand with the operators sitting on the bow besides the retainer. To keep the blade up during travel it was attached to the turret with additional wires. This made it possible to use the vehicle as tank, too. 200 vehicles were ordered by IJA.

Until surrender around 50 vehicles were produced by Mitsubishi. Some were used on Iwo Jima and the Philippines. One vehicle was captured by US troops on Iwo Jima and sent to Aberdeen Proving Ground and is still on display there but as tank without the dozer blade.

After the war the production continued as there was an urgend need for those vehicles to remove the remains of houses being bombed. Only changes were removing the turret and the bow MG Mount to demilitarise the vehicles

Image


There was also a version with turret removed and the bow armor replaced by a straight steel plate with two vertical hatches. Driver and operator sat on the fighting compartment, partly covered by the new frontal shield. The blade was mounted hinged on the hull between the first two roadwheels. It could be elevated by hand using wires mounted on a retainer on the lower bow armour.

Image


No further data available.



E) Light Armoured Dozer

Image

At least one Type 97 Tankette Te-Ke was converted to a dozer vehicle. The blade was operated by hand through the turrer after removing the gun shield.

No further data available.



F) Experimental Tunnel Digger

Image

A large shovel mounted on a raisable frame on the bow of a Chi-Ha KAI.

No further data available.



G) Experimental Earthmover

Image

A large frontshovel mounted on the bow of a Chi-Ha KAI.

No further data available.



Changes and additions:

04.11.2014
- Armoured Dozers changed due to new, more detailed infos.
- Light Armoured Dozer added
- Experimental Tunnel Digger added
- Experimental Experimental Earthmover added


Yours

tom! ;)
Last edited by tom! on Tue Nov 04, 2014 7:24 pm, edited 2 times in total.

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Re: The japanese armour and other vehicles thread

Postby tom! » Fri Jul 05, 2013 1:35 pm

Hi.

21) Special Purpose Railway Vehicles

For military railway transport, maintenance and guarding IJA developed and used several special vehicles. After 1941 IJA also started to coordinate the civil transport on the home islands. Railway units also operated several standardised and improvised armoured trains and a railway gun.

IJA only allowed infantry and cavalry to use tanks and armoured vehicles with fixed armament. So the railroad vehicles only had gun ports for infantry weapons.


A) Sumida RSW Railroad Car

Image

During occupation of Manchuria the railways were the most important transport routes. So guarding and maintaining these lifelines was most important. Sumida had already developed armoured cars for IJA and so they also developed a special 4-wheeled armoured vehicle from a commercial truck for railway security duties and transport.

The body was covered with 6 mm face-hardened armour plates riveted on a frame. The armour was almost completely vertical except the frontal armour of the driver´s cabin and the upper engine compartment armour which was sloped. An access hatch on each side of the engine compartment allowed maintenance of the gasoline engine. The armour plate in front of the radiator had large vertical slits and could be opened to the top to increase cooling. A third headlight as standard for locomotives was mounted on the front of the engine compartment.

The driver sat on the (in driving direction) right side. He looked through a large hatch opening to the top with a visor port. On his left sat another crewman. He could fire with a rifle, MG or pistol through a hatch with two small sliding doors. Similar weapon ports were on each side of the cabin. The rear crew compartment was wider than the driver´s cabin. In the forward part were two large access doors. Behind the doors were two more weapon ports on each side. On the crew compartment was a large cylindrical turret with weapon ports similar to the ones used on the first improvised armoured cars.

The wheels were steel disks with rubber bands. After removing these bands the vehicle could drive on the tracks like a locomotive. Meanwhile the rubber bands were carried on the rear of the crew compartment. A prototype was finished in 1929 and used in Manchuria. The performance was not satisfying but the general idea was rated useful.

No further info available.



under construction

Yours

tom! ;)
Last edited by tom! on Tue Nov 04, 2014 7:25 pm, edited 1 time in total.

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Re: The japanese armour and other vehicles thread

Postby tom! » Sat Aug 10, 2013 11:01 am

Hi.

Sorry for the unexpected interruption.

Due to some heavier (but not serious) health problems I had to stay away some weeks and I will have to stay away some more weeks for medical rehab.

But I will be back..... :D

Yours

tom! ;)

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Re: The japanese armour and other vehicles thread

Postby Ricky » Sat Aug 10, 2013 6:46 pm

You look after yourself :)
"Study the past, if you would divine the future"
-Confucius

"I am pedantic, I'm just being overshadowed by Ricky so it isn't as noticable as it would else have been"
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Re: The japanese armour and other vehicles thread

Postby Tankdriver » Sat Oct 19, 2013 3:47 pm

Thank you, Tom! Plenty of new and interesting information on Japanese machines. I hope your health is good?
In Russia there are two working instance of Japanese tanks. Both are assembled from pieces of destroyed tanks, and brought to a running state. Tank Shinhoto Chi-Ha, as far as I know, the only working tank of this type in the world.
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