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O-I

AnnoJ24_Mi_To_130_tons.png
Battle Tier
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Overview
Mouse over "
Well, the ones further down, of course.
" for more information
[Client Values; Actual values in
Specifically, the mismatch in crew values caused by commander's 10% crew skill bonus. Outside of a crew of 1 commander only, 100% crew is a fiction. The client values, given for 100% crew, will normally be taken into battle with 110% crew skill members aside from specific functions, causing their actual performance to deviate from the expected client value. These differences are taken into account in tooltip boxes.
]
950,000  Credits Cost
1060212 HP Hit Points
150.36/150.539.8/155 t Weight Limit
Crew
  1. Commander
  2. Gunner
  3. Driver
  4. Radio Operator
  5. Radio Operator
  6. Loader
Mobility
11001200 hp Engine Power
29.4/10 km/h Speed Limit
1618 deg/s Traverse
7.3230.15 hp/t Power/Wt Ratio
NoNo Pivot
Armor
// mm Hull Armor
150/150/105150/150/105 mm Turret Armor
Armament







{{#ifeq:ARMOR_PIERCING|ARMOR_PIERCING||



{{#ifeq:HIGH_EXPLOSIVE|ARMOR_PIERCING||


AP//HE







{{#ifeq:HOLLOW_CHARGE|ARMOR_PIERCING||



{{#ifeq:HIGH_EXPLOSIVE|ARMOR_PIERCING||


AP/HEAT/HE
Shells




















0/3600/190




















540/4800/660
Shell Cost
300/300/360700/700/890 HP Damage
175/201/53121/150/75 mm Penetration



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5 r/m 

Standard Gun

Reload Times
Nominal: 12 s
50% Crew: 14.87 s
75% Crew: 12.98 s
100% Crew: 11.51 s
Rammer: 10.36 s
Vents: 11.26 s
Both: 10.13 s
Both and BiA: 9.91 s
Both and Max Crew %: 9.5 s

See Crew, Consumables, or Equipment for more information.



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2.31 r/m 

Standard Gun

Reload Times
Nominal: 26 s
50% Crew: 32.21 s
75% Crew: 28.12 s
100% Crew: 24.93 s
Rammer: 22.44 s
Vents: 24.38 s
Both: 21.94 s
Both and BiA: 21.47 s
Both and Max Crew %: 20.58 s

See Crew, Consumables, or Equipment for more information.
Rate of Fire






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1500

Standard Gun

Using Shell Type 1 (300 Damage):


Theoretical Damage Per Minute
Nominal DPM: 1500
50% Crew: 1212
75% Crew: 1386
100% Crew: 1563
100% Crew
Vents: 1599
Rammer: 1737
Both: 1776
Both and BiA: 1815
Both and Max Crew %: 1893

Advantageous Damage Per Minute
First-shot DPM: 1800
50% Crew: 1512
75% Crew: 1686
100% Crew: 1863
100% Crew
Rammer: 2037
Vents: 1899
Both: 2076
Both and BiA: 2115
Both and Max Crew %: 2193

See here, here, or here for more information.

Standard Gun

Using Shell Type 2 (300 Damage):


Theoretical Damage Per Minute
Nominal DPM: 1500
50% Crew: 1212
75% Crew: 1386
100% Crew: 1563
100% Crew
Vents: 1599
Rammer: 1737
Both: 1776
Both and BiA: 1815
Both and Max Crew %: 1893

Advantageous Damage Per Minute
First-shot DPM: 1800
50% Crew: 1512
75% Crew: 1686
100% Crew: 1863
100% Crew
Rammer: 2037
Vents: 1899
Both: 2076
Both and BiA: 2115
Both and Max Crew %: 2193

See here, here, or here for more information.

Standard Gun

Using Shell Type 3 (360 Damage):
With wholly penetrating hits

Theoretical Damage Per Minute
Nominal DPM: 1800
50% Crew: 1454.4
75% Crew: 1663.2
100% Crew: 1875.6
100% Crew
Vents: 1918.8
Rammer: 2084.4
Both: 2131.2
Both and BiA: 2178
Both and Max Crew %: 2271.6

Advantageous Damage Per Minute
First-shot DPM: 2160
50% Crew: 1814.4
75% Crew: 2023.2
100% Crew: 2235.6
100% Crew
Rammer: 2444.4
Vents: 2278.8
Both: 2491.2
Both and BiA: 2538
Both and Max Crew %: 2631.6

See here, here, or here for more information.






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1617

Standard Gun

Using Shell Type 1 (700 Damage):


Theoretical Damage Per Minute
Nominal DPM: 1617
50% Crew: 1302
75% Crew: 1498
100% Crew: 1687
100% Crew
Vents: 1722
Rammer: 1876
Both: 1918
Both and BiA: 1960
Both and Max Crew %: 2044

Advantageous Damage Per Minute
First-shot DPM: 2317
50% Crew: 2002
75% Crew: 2198
100% Crew: 2387
100% Crew
Rammer: 2576
Vents: 2422
Both: 2618
Both and BiA: 2660
Both and Max Crew %: 2744

See here, here, or here for more information.

Standard Gun

Using Shell Type 2 (700 Damage):


Theoretical Damage Per Minute
Nominal DPM: 1617
50% Crew: 1302
75% Crew: 1498
100% Crew: 1687
100% Crew
Vents: 1722
Rammer: 1876
Both: 1918
Both and BiA: 1960
Both and Max Crew %: 2044

Advantageous Damage Per Minute
First-shot DPM: 2317
50% Crew: 2002
75% Crew: 2198
100% Crew: 2387
100% Crew
Rammer: 2576
Vents: 2422
Both: 2618
Both and BiA: 2660
Both and Max Crew %: 2744

See here, here, or here for more information.

Standard Gun

Using Shell Type 3 (890 Damage):
With wholly penetrating hits

Theoretical Damage Per Minute
Nominal DPM: 2055.9
50% Crew: 1655.4
75% Crew: 1904.6
100% Crew: 2144.9
100% Crew
Vents: 2189.4
Rammer: 2385.2
Both: 2438.6
Both and BiA: 2492
Both and Max Crew %: 2598.8

Advantageous Damage Per Minute
First-shot DPM: 2945.9
50% Crew: 2545.4
75% Crew: 2794.6
100% Crew: 3034.9
100% Crew
Rammer: 3275.2
Vents: 3079.4
Both: 3328.6
Both and BiA: 3382
Both and Max Crew %: 3488.8

See here, here, or here for more information.
Damage Per Minute


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0.43 m 

With 50% Crew: 0.533 m
With 75% Crew: 0.465 m
With 100% Crew: 0.412 m
With BiA: 0.403 m
With BiA and Vents: 0.394 m
Maximum possible: 0.378 m

For more details, see Crew


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0.58 m 

With 50% Crew: 0.718 m
With 75% Crew: 0.627 m
With 100% Crew: 0.556 m
With BiA: 0.544 m
With BiA and Vents: 0.532 m
Maximum possible: 0.51 m

For more details, see Crew
Accuracy


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3.2 s 

With 50% Crew: 3.964 s
With 75% Crew: 3.461 s
With 100% Crew: 3.068 s
With GLD: 2.789 s
With BiA: 3.001 s
With BiA and Vents: 2.935 s
With both and GLD: 2.669 s
Maximum possible: 2.558 s

For more details, see Crew or Equipment


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3.7 s 

With 50% Crew: 4.583 s
With 75% Crew: 4.002 s
With 100% Crew: 3.548 s
With GLD: 3.225 s
With BiA: 3.47 s
With BiA and Vents: 3.394 s
With both and GLD: 3.086 s
Maximum possible: 2.958 s

For more details, see Crew or Equipment
Aim time
1818 deg/s Turret Traverse
360° Gun Arc
-10°/+20°-10°/+20° Elevation Arc
10060 rounds Ammo Capacity
General
2020 % Chance of Fire






370 m 

With 50% Crew: 290.7 m
With 75% Crew: 330.4 m
With 100% Crew: 370 m
With Recon and Situational Awareness: 388.7 m
With Coated Optics: 407 m
With Binocular Telescope: 462.5 m
Maximum possible: 529.7 m

For more details, see Skills or Equipment






370 m 

With 50% Crew: 290.7 m
With 75% Crew: 330.4 m
With 100% Crew: 370 m
With Recon and Situational Awareness: 388.7 m
With Coated Optics: 407 m
With Binocular Telescope: 462.5 m
Maximum possible: 529.7 m

For more details, see Skills or Equipment
View Range


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300 m 

With 50% Crew: 242.2 m
With 75% Crew: 277.4 m
With 100% Crew: 312.9 m
With 100% Signal Boost: 360 m
When affected by 100% Relaying: 330 m
Maximum possible: 450.4 m

For more details, see Skills or Equipment


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425 m 

With 50% Crew: 343.1 m
With 75% Crew: 392.9 m
With 100% Crew: 443.2 m
With 100% Signal Boost: 510 m
When affected by 100% Relaying: 467.5 m
Maximum possible: 638 m

For more details, see Skills or Equipment
Signal Range
Values are Stock - click for Top


VI

AnnoJ24_Mi_To_130_tons.png

950000

The O-I is a Japanese tier 6 heavy tank.

Development of the superheavy tank was started after the Battles of Khalkhyn Gol in 1939. The vehicle was designed as a maneuverable fire unit that was unprecedented in scale—its hull alone weighed 100 tons. Only one prototype was built, without a turret and made of construction steel. Trials were discontinued due to the unreliable engine; at the end of 1944, the prototype was scrapped. The 15 cm howitzer was to be mounted on the tank after its assembly.

Also known as Derp Demon. The O-I is basically a KV-2 on steroids. Not only does it carry the most powerful gun of its tier, the O-I also sports some of the toughest protection in tier 6; it easily can hold itself against tier 7 tanks with its thick armor & raw firepower. It had two gun choices; a powerful 10cm AP gun with high penetration and a trademark 15cm "derp gun" with insane alpha damage. The O-I has the similar distinctive look like it's brother "O-I exp" and offers a unique, fun play style with it's Insane armor & raw firepower.

However, like every Japanese heavy tank after tier 4, it is huge and massive (even larger than most of tier 10s) as well as quite slow, and will usually become the primary target of SPGs, gold rounds and flankers.

As of update 1.9, the O-I is no longer researched from the O-I Exp. it is instead researched from the Chi-Nu.

The O-I leads to the O-Ni.

Modules / Available Equipment and Consumables

Modules

Ico_gun_alpha.png

Guns

Tier Gun Penetration
(mm)
Damage
(HP)
Rate of fire
(rounds/minute)
Dispersion
(m/100m)
Aiming time
(s)
Weight
(kg)
Price
(Credits)

VII 10 cm Cannon Type 92 175/201/53 300/300/360 5 0.43 3.2 1792 68500
VII 15 cm Howitzer Type 96 121/150/75 700/700/890 2.31 0.58 3.7 1432 71200

Ico_engine_alpha.png

Engines

Tier Engine Engine Power
(hp)
Chance of Fire on Impact
(%)
Weight
(kg)
Price
(Credits)

VII 2x Kawasaki Type 98 V-12 (550) 1100 20 1020 51000
VIII 2x Kawasaki Type 98 V-12 (600) 1200 20 1020 77500

Ico_suspension_alpha.png

Suspensions

Tier Suspension Load Limit
(т)
Traverse Speed
(gr/sec)
Rmin Weight
(kg)
Price
(Credits)

V O-I 150.5 16 B/2 25000 10000
VI O-I Kai 155 18 B/2 25000 19800

Ico_radio_alpha.png

Radios

Tier Radio Signal Range
(m)
Weight
(kg)
Price
(Credits)

II Type 94 Mk. 4 Otsu 300 40 0
IV Type 94 Mk. 4 Hei 350 90 2350
VI Type 96 Mk. 4 Bo 425 50 14000

Compatible Equipment

Low Noise Exhaust System Class 2 Medium Spall Liner Camouflage Net Class 2 Coated Optics Class 2 Experimental Optics Wear-Resistant Gun Laying Drive Improved Configuration Venting System Innovative Loading System Enhanced Gun Laying Drive Class 2 Improved Hardening Class 2 Additional Grousers Class 2 Modified Configuration Class 2 Improved Rotation Mechanism Class 2 Improved Aiming Class 2 Improved Ventilation Class 2 Binocular Telescope Class 2 Gun Rammer Class 2 Turbocharger Class 2 

Compatible Consumables

Automatic Fire Extinguisher Natural Cover Optical Calibration Aim Tuning Experienced Firefighters Manual Fire Extinguisher Pre-Battle Maintenance Vent Purge Large First Aid Kit Large Repair Kit Duty Comes First Shell Organizer Quality Oil Orderly Ammo Rack Focus on Target Onigiri Increased Focus Small First Aid Kit Small Repair Kit Gearbox Intricacy Steady Hand Combat Course 


Player Opinion

Pros and Cons

Pros:

- Choice of two guns: 10cm gun and 15cm gun, both of which have ridiculously high ammunition stock.

- High Hp (1060) + insane 150mm front armor with next to no true weakspots gives even some tier VII's problems, and able to take tremendous punishment before going down.

- Excellent view range, especially for a heavy.

- Has tall turret, very easy to shoot over cover & allied tanks.

- 15cm is capable of two-shotting most tanks in its tier, like the KV-2, even with AP. It is also slightly more accurate.

- Insane mass + high hp engine makes it good at shoving dead tanks for additional cover and highly resistant to rams.

- Because of Large Mass, tank is able to mount Superheavy spall liner, increasing already excellent survivability even more.

- Moderately easy stock grind since the 10cm gun deals a large amount of damage and has great penetration. And doesn't need tracks to mount modules and lacks additional turret to research.

- Shares most of its modules with other later Japanese super-heavies. You can grind and research the radio and engine for the next tank.

- Fear factor: powerful, high damaging gun + thick armor all around makes it a scary tank to face.


Cons:

- Huge size and weak side armor leaves O-I very vulnerable to flanking, artillery and gold rounds. Though rear armor is thicker than sides, and the rear mini turret is strong as the front ones. Difficult to hide and sports hideous camo ratings.

- Both guns, especially the howitzer, are inaccurate, have long aim time and poor gun handling.

- While surprisingly accurate at long range, ironically the howitzer has an infuriating tendency to miss at point blank range, often with fatal results.

- Horrifyingly poor mobility, bad ground resistance, slow acceleration and bad top speed (25 km/h) makes for a really slow tank.

- Terrible camouflage ratings, can be easily spotted.

- Absolutely terrible DPM on both guns; 15cm has even longer reload than KV-2 and 10cm has absolutely terrible DPM (300 worse than O-I Experimental despite being higher tier!)

- Inner side armor is only 30mm thick and possible to hit and overmatch from hole above tracks.

- Will still have to rely on HE in most cases against some tier 7s.


Performance

In terms of firepower, the O-I has it in spades. Stock, the tank comes with an excellent 10cm gun capable of going through any tank you might have to face while dealing respectable damage with decent accuracy, but a rather long aim time. There is a second gun for the O-I and it is a 15cm devastating alpha howitzer, similar to that mounted on the KV-2, with a slightly slower rate of fire, lower accuracy and a horrid aim time. However, this gun can be a lot of fun to play, especially when striking lightly armored foes which is common at tier 6.

Game play with the 10cm gun allows you to engage targets at a longer range and good penetration. It also allows you to play a more supportive role by sniping when you are bottom tier. With this gun, it allows an O-I to laugh at opposing heavy tank's armor, while you effortlessly bounce incoming fire. With the 10cm gun, it also allows you to more reliably handle opposing O-Is. However, 10cm is more ineffective against higher tier heavies as well as loses its feared ability to one-shot tanks. Be wary that while the gun reloads faster than howitzer, it still has very low DPM and poor accuracy which means that O-I wont deal damage very quickly.

With the 15cm derp cannon, your play style will have to change radically to make up for the shortcomings of the gun's long aim time and poor accuracy. This means that getting up close and personal in any brawl will allow you to negate your gun's main problems and ensure every shell hits. Having knowledge of what might appear in front of your tank is crucial as well, to make sure the correct shell is loaded. The AP shell in the 15cm gun is better than that in the KV-2, with improved penetration. 121mm may not seem like much, but at tier 6, it is sufficient to go through many tanks frontally. In exchange for the better AP shells, the HE shells do not penetrate as much armor, as compared to the ones on the KV-2. However, thin-skinned targets will be wrecked easily by it. When you are bottom tier, the large caliber HE shell will allow you to do damage in all situations, as long as the shell hits your target.

In conclusion, the O-I is ridiculously powerful for a tier 6 vehicle. It has a flexible choice of guns for different play styles. The O-I has also seen increased use in tier 6 strongholds due to it's armor and derp gun. It should be noted that the gun depression is a lie - it is only -10 degrees in the very front in between the two turrets, and is between 4 degrees and 6 degrees everywhere else.


Early Research

  • The Type 96 Mk. 4 Bo radio carries over from the Chi-Nu and should be installed immediately.
  • Research either the 15 cm Howitzer Type 96 or the 2x Kawasaki Type 98 V-12 (600) engine.
  • Research whichever module you didn't choose previously.
  • Finally, research the O-I Kai suspension.


Suggested Equipment


Improved VentilationSpall Liner Tank Gun Rammer "Wet" Ammo Rack Vertical Stabilizer Coated Optics 


Gallery

Historical Info

The O-I (オイ車 Oi-sensha) was a super-heavy tank prototype designed by the Imperial Japanese Army during the Second Sino-Japanese War after the Battles of Nomonhan in 1939. The O-I is one of the Second World War’s more secretive tank projects, with documentation regarding the tank being kept private for over 75 years at Wakajishi Shrine, Fujinomiya. Surviving files have been purchased by FineMolds Inc., and publicly previewed in mid-2015. The multi-turreted 150-ton tank was designed for use on the Manchurian plains as a supportive pillbox for the Imperial Japanese against the Soviet Union. The project was disbanded four years after the initial development began, deemed unsatisfactory for continuation in 1943 after the lack of resource material for the prototype.

OI_technical_drawing.jpg



History and development

After 1939, the Imperial Japanese Army quickly came to realize that previous forms of mechanized warfare were proved inefficient after their defeat at Khalkhin Gol.

Development of the super-heavy project was spearheaded by Colonel Hideo Iwakuro, the head of the Ministry of War of Japan (陸軍省 Rikugun-shō). Iwakuro opposed Japan’s advances towards the Soviet Union in 1939, and with the Japanese defeat, he decided to initiate a project to construct a heavily armored tank capable of withstanding large-calibre field cannons. Iwakuro assigned Colonel Murata of the 4th Technical Research Group to design and construct the super heavy tank in 1939. Colonel Murata noted Iwakuro’s words as described;


「満州の大平原で移動トーチカとして使えるような巨大戦車を作ってほしい。極秘でだ。」 “I want a huge tank built which can be used as a mobile pillbox in the wide open plains of Manchuria. Top secret.”


「今の戦車の寸法を2倍に延ばして作れ。」 “Make the dimensions twice that of today’s tanks.”


The 4th Technical Research Group began designing the super-heavy vehicle throughout 1940, attempting to meet Colonel Iwakuro’s vague instructions on the ultimate goal of the project. By March 1941, the research group had finished initial tank design and was ready to begin construction. The following month, a group of pre-selected engineers were chosen to partake in the building of the super-heavy tank. One recorded engineer was Shigeo Otaka, who stated they were sent to the 4th Technical Research Group’s previous headquarters in Tokyo. There, they were guided through a barracks containing multiple small fitting rooms, where they were to conduct meetings and reports on the progress of construction of the super-heavy vehicle. Towards the end of the barracks facility was a fully-enclosed room devoid of windows, with soundproofed walls to prevent external personnel from overhearing discussions related to the project. Each officer present possessed a portion of the project’s blueprint, which, when assembled, projected the full design of the tank, labelled "Mi-To". The name originated from a collection of the Mitsubishi industry and the city, Tokyo; given to the vehicle to uphold secrecy of the tank’s project.


Colonel_Murata.png Colonel_Iwakuro.jpg Colonels Murata and Iwakuro


The chosen engineers voiced their concerns regarding the Mi-To’s design noting that previously, the largest-sized Japanese tank had been the prototype Type95 Heavy in 1934. Issues that had been noted with heavy tank experiments in the years preceding the Mi-To showing Japan’s generally unsuccessful testing on multi-turreted vehicles exceeding the weight of standard armored vehicles. However, with the threat of a second Russo-Japanese conflict becoming more apparent, the project continued despite the engineer’s doubts on the size and mobility of the vehicle.

Surviving_Mi-To_engineers.jpg Four engineers who survived to record the dealing had with the project


On April 14th 1941, the engineers began the construction of the Mi-To under secretive means. This entailed privately-made mechanical parts and equipment being shipped to the construction zone. Colonel Murata’s original concept was to complete the super-heavy tank three months after the initiation of Mi-To’s construction. This, ultimately, did not come into fruition; as technical issues on the project began to arise. Due to the limitation on material consumption by the government, the amount of parts that could be secretly shipped-in began to dwindle. By the first month of construction, essential construction resources had been depleted and the issues with the vehicle’s cooling system further caused delays. The construction of the Mi-To was postponed until January 1942, a delay of nine months.


After the Mi-To’s construction was resumed, the hull was completed on February 8th 1942. The tank had reached near-completion and was being prepared for mobility testing. Mitsubishi built the four turrets for the tank in May of the same year. Initial assembly of the tank’s armament took place soon after the turret’s superstructures were completed. However; the project once again did not have the necessary resources needed for the few remaining parts required for the final assessment. Due to this, the primary turret was removed as it lacked a 35-millimetre-thick roof plate, which had not yet arrived. Thus, the project was put on standby, until further development could continue. The total weight of the vehicle at the time was 96 tons, due to the lack of remaining structural plates and absent 75mm bolted-on armor.


O-I_documents_previewed_by_FineMolds.png O-I documents previewed by FineMolds

The date on which the construction of the tank resumed is unknown, although active testing of the tank was scheduled for late 1943. The tank was unveiled to the Imperial Japanese Army’s highest command in 1943, and received a name change to O-I. This followed Japanese naming convention (O translating to Heavy, I for First, making it "First Heavy") that was standard. In his place was Lieutenant Colonel Nakano, Murata's assistant and colleague. Tomio Hara, head of the Sagamia Army Arsenal, was also present. Following the demonstration, senior officials within the IJA requested that field trials begin in August of the same year. The tank was disassembled at 2:00 AM one night in June of 1943 and sent to the Sagami Army Arsenal in Sagamihara, 51 kilometres from Tokyo. The vehicle arrived at the depot in June, and was reassembled and tested on the 1st of August.

On the day of the trials, the O-I performed satisfactorily until the second hour of the tests. While manoeuvring on off-road terrain, the tank sank into the ground by up to a meter; attempts at traversing the hull to extricate the vehicle proved fruitless, resulting in further sinking due to the vehicle’s suspension coils compressing. The tank was eventually towed out, and further testing was continued on concrete. However, the earlier damage to the suspension resulted in vehicle’s movement damaging the concrete, which in turn, further damaged the suspension bogies to the point that further testing could not continue. The trials were postponed, and later cancelled the following day.


Nevertheless, the trials conducted at the testing field were considered to be a success, and the vehicle was deemed ready for use in spite of its flaws. The engineers began disassembly of the tank on the 3rd of August due to resources being limited and the inability to maintain the tank in the field. Disassembly of the tank was completed on August 8th. Two days later, the engineers noted in a log that they were to inspect the parts and conduct research to fix the issues the O-I would face.


The fate of the O-I after its field-trials which took place on the 1st of August is unclear. Russian reports claim the Japanese were in possession of a wooden O-I mock-up mounting a Daimler-Benz DB 601A engine in 1945, however other sources point to the scrapping of the remaining parts of the same year. The remains of the O-I reside at the Wakajishi Shrine, with a track link of the prototype still present.

OI_Track_Link.jpg Remaining track link of the prototype O-I tank


Design

The O-I was conceived out of the necessity to produce an armored vehicle capable of withstanding modern weaponry being able to return fire with similar firepower. The O-I was designed to act as a mobile pillbox, supporting infantry and mechanized groups along the border of the Soviet Union. The tank had a length of 10.1 meters, width of 4.8 meters, and a height of 3.6 meters. The dimensions of the vehicle closely matched those of the Panzer VIII Maus. The tank was envisioned to have a standard thickness of 150 millimeters front and rear, in order to protect against common anti-tank weapons of the time, yet it was constructed with armor 75 millimeters thick. However, an additional armor plate could be bolted on to bring the total thickness of the armor to 150 millimeters. The use of additional armor allowed for ease of construction and transportation, while also providing the tank with additional defense. Side armor on the hull superstructure was 70 millimeters thick. The additional armor plates were 35 millimeters thick, but armor surrounding the suspension was only 35 millimeters thick. This made the tank’s theoretical armor on the side 75 millimeters. There were eight wheel-supporting beams located on both sides of the suspension area which added an additional 40 millimeters of armor to specific locations on the side of the O-I. 40 ladder pieces were placed around the tank to provide crew with the ability to climb onto of the vehicle with ease.


The two 47mm cannons used in the two frontal turrets were also modified to fit the armor layout of the tank. The weapon’s barrels were reinforced with steel to secure them to the tank, due to the standard gun not adequately fitting into the turret.

O-I_armor_plating.png


The tank was both designed and built with two inner armor plates to divide the interior into three sections; walls with two doors each and an ultimate thickness of 20mm. This allowed the crew and modules to remain relatively safe while the structure was kept safe with supporting stands. These supports allowed the interior armor plates to stay stable and also prevented collapse. Inside the O-I were two Kawasaki V-12 engines, both located in the rear, parallel lengthwise, to give room for the rear turret operator and transmission. The transmission copied that of the Type97 Chi-Ha’s, but used larger parts and gears making the total weight heavier. The vehicle had a coil spring system, with eight 2 wheeled boggies, totalling 16 individual wheels.

O-I_documents.jpg


General

  • Name: O-I
  • Factory: Private - Mitsubishi
  • Units Produced: 1
  • Type: Super Heavy Tank
  • Year Built: February 8th 1942
  • Length: 10.1 m
  • Width: 4.8 m
  • Hull Width: 4833 mm
  • Height Full: 3.6 m
  • Turret height: 1065 mm
  • Track width: 800 mm
  • Track Pitch: 300 mm
  • Track Thickness: 58 mm Half, 108 mm Full
  • Total Weight: 150t (96t prototype)

Engine=

  • Name: Type98 V12 Kawasaki
  • Power: 550hp (1100hp total with second engine)
  • Weight: 1020kg
  • Gears: 6
  • Lubricant type: Oil
  • Maximum speed: 40kmh onroad (96 ton prototype), 29.4 kmh (design) onroad

Hull

  • Hull height 2530 mm
  • Hull Width: 4833 mm
  • Upper Front Plate: 150mm @ 56,29°
  • Lower Front Plate: 150mm @ 45°
  • Lowest Front Plate: 70mm @ 70,5°
  • Side plate: 35mm @ 0° + Bolted 35mm @ 0°
  • Superstructure side plate: 75mm @ 0°
  • Upper Rear Plate: 150mm @ 18°
  • Lower Rear Plate: 150mm @ 33,01°
  • Lowest Rear Plate: 30mm @ 75,99°
  • Top plate: 50mm @ 0°
  • Bottom plate thickness: 30mm @ 0°

Primary Turret=

  • Turret height: 1065 mm
  • Turret side faces: 150mm @ 90°
  • Turret top: 50mm @ 0°


Armament

  • Model: Type96 15cm Howtizer
  • Weight: 4,140 kg
  • Elevation: -5 ° to + 20 °
  • Amount of ammunition: 100+
  • Type of ammunition: Type95 APHE, Type92 Spifire HE, 4th Year HEAT


Ammunition Types

  • Name: Type95 APHE
  • Shell weight: 36000g
  • Muzzle Velocity: 540m/s
  • Penetration: 125mm @ 230m, 120mm @ 510m, 112mm @ 755m, 102mm @ 1000m
  • Explosives: 6150g
  • Name: Type92 Spifire HE
  • Shell weight: 36000g
  • Muzzle Velocity: 540m/s
  • Explosives: 6150g
  • Name: 4th Year HEAT
  • Shell weight: 21040g
  • Muzzle Velocity: 650m/s
  • Explosives: 6150g


Secondary Armament

  • Model: Type1 47mm Experimental
  • Weight: 600(+/-) kg
  • Elevation: -10 ° to + 20 °
  • Amount of ammunition: 100+
  • Type of ammunition: Type1 APHE, Tungsten Alloy Toku Kou Prototype
  • Name: Type1 APHE
  • Shell weight: 36000g
  • Muzzle Velocity: 810m/s
  • Penetration: 65mm @ 200m, 65mm @ 500m, 50mm @ 1000m, 45mm @ 1500m
  • Explosives: 250g
  • Name: Tungsten Alloy Toku Kou Prototype
  • Shell weight: 36000g
  • Muzzle Velocity: 810m/s
  • Penetration: 85mm @ 0m, 79mm @ 200m, 70mm @ 500m, 56mm @ 1000m, 45mm @ 1500m
  • Explosives: 250g


Historical Gallery

Historical Accuracy Errata

The following are consensus errors or inconsistencies which have been identified with the configuration of the vehicle in question and conflict with information available on the public record. The causes for these divergences in the game are normally not disclosed and may be rooted in game balance.

The 150 ton O-I was never supposed to mount the 10cm gun.
  • The hull rear armor was decreased for balancing reason


Sources and External Links

Japan
Light Tanks IRenault Otsu IIType 95 Ha-Go IIType 97 Te-Ke IIIType 97 Chi-Ha IIIType 98 Ke-Ni IVType 5 Ke-Ho
Medium Tanks IIChi-Ni IIType 89 I-Go/Chi-Ro IVType 1 Chi-He VType 3 Chi-Nu VType 3 Chi-Nu Kai VIType 4 Chi-To VIIType 5 Chi-Ri VIIISTA-1 VIIISTA-2 IXType 61 XSTB-1
Heavy Tanks IIIType 91 Heavy IVType 95 Heavy VO-I Experimental VIHeavy Tank No. VI VIO-I VIIO-Ni VIIIO-Ho IXType 4 Heavy XType 5 Heavy
Tank Destroyers
Self-Propelled Artillery
Heavy Tanks
USA VT14 VT1 Heavy Tank VIPawlack Tank VIM6 VIIKing Tiger (Captured) VIIM-II-Y VIIT29 VIIIChrysler K VIIIChrysler K GF VIIIT26E5 VIIIT26E5 Patriot VIIIM54 Renegade VIIIT77 VIIIM-III-Y VIIIM-IV-Y VIIIM6A2E1 VIIIT32 VIIIT34 VIIIT34 B IXAE Phase I IXConcept 1B IXM-VI-Y IXM103 IXT54E1 XM-V-Y XT110E5 XT57 Heavy Tank
UK VChurchill I VExcelsior VIChurchill VII VITOG II* VIIBlack Prince VIIFV201 (A45) VIIICharlemagne VIIICaliban VIIIGonsalo VIIICaernarvon VIIICaernarvon Action X IXFV4201 Chieftain Proto IXConqueror XFV215b XSuper Conqueror XT95/FV4201 Chieftain
Germany IVPz.Kpfw. B2 740 (f) IVDurchbruchswagen 2 VITiger 131 VIVK 30.01 (P) VIVK 36.01 (H) VIIVK 45.03 VIITiger I VIITiger (P) VIIIVK 100.01 (P) VIIIVK 168.01 (P) VIIIVK 168.01 Mauerbrecher VIIIVK 75.01 (K) VIIIE 75 TS VIIILöwe VIIITiger II VIIIVK 45.02 (P) Ausf. A IXE 75 IXMäuschen IXVK 45.02 (P) Ausf. B XE 100 XPz.Kpfw. VII XMaus XVK 72.01 (K)
France IVB1 VBDR G1 B VIARL 44 VIIAMX M4 mle. 45 VIIIAMX 50 100 VIIIAMX M4 mle. 49 VIIIAMX M4 mle. 49 Liberté VIIIAMX 65 t VIIISomua SM VIIIFCM 50 t IXAMX 50 120 IXLorraine 50 t IXAMX M4 mle. 51 XAMX 50 B XAMX M4 mle. 54
USSR VChurchill III VKV-220-2 VKV-220-2 Beta Test VKV-1 VKV-1 shielded VIKV-1S VIKV-2 VIKV-2 (R) VIKV-85 VIObject 244 VIT-150 VIIIS VIIKV-3 VIIKV-122 VIIIS-2M VIIIS-2 shielded VIIIS-2 VIIIIS-3 VIIIIS-6 VIIIIS-6 B VIIIKV-5 VIIIKV-4 VIIIIS-5 (Object 730) VIIIIS-3A VIIIIS-3A Peregrine VIIIKirovets-1 VIIIKV-4 Kreslavskiy VIIIObject 252U Defender VIIIObject 252U VIIIIS-M VIIIObject 703 Version II VIIIIS-2-II IXT-10 IXObject 777 Version II IXObject 257 IXObject 705 IXIS-3-II IXST-I XIS-4 XIS-7 XObject 260 XObject 705A XObject 277 XObject 279 early XST-II XObject 780
China VIIIS-2 VIIIWZ-111 VIIIWZ-111 Alpine Tiger VIII110 VIII112 IXWZ-111 model 1-4 IXWZ-114 X113 X113 Beijing Opera XWZ-111 model 5A XWZ-111 Qilin
Japan IIIType 91 Heavy IVType 95 Heavy VO-I Experimental VIHeavy Tank No. VI VIO-I VIIO-Ni VIIIO-Ho IXType 4 Heavy XType 5 Heavy
Czechoslovakia VIIŠkoda T 45 VIIVz. 44-1 VIIIŠkoda T 56 VIIITNH 105/1000 IXTNH T Vz. 51 XVz. 55
Sweden VIIIEmil I VIIIEMIL 1951 VIIIBofors Tornvagn IXEmil II IXStrv K XKranvagn
Italy VIICarro d'assalto P.88 VIIIProgetto CC55 mod. 54 VIIIBisonte C45 IXProgetto C50 mod. 66 XRinoceronte
Poland VII45TP Habicha VIII50TP prototyp VIII53TP Markowskiego IX50TP Tyszkiewicza X60TP Lewandowskiego
ja:Tank:J24 Mi To 130 tons