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This shall be the general thread for all things soviet tanks. I shall start by posting an article I just wrote for my blog. I would recommend Archive Awarness which is an excellent blog about Soviet tanks and their experiences with other nation's tanks.
ATTENTION DUELISTS: @Toxn @LostCosmonaut @Lord_James @DIADES @Datengineerwill @Whatismoo @Kal @Zadlo @Xoon detailed below is the expected format of the final submission. The date is set as Wednesday the 19th of June at 23:59 GMT. Again, incomplete designs may be submitted as they are and will be judged as seen fit. FINAL SUBMISSION: Vehicle Designation and name [insert 3-projection (front, top, side) and isometric render of vehicle here) Table of basic statistics: Parameter Value Mass, combat Length, combat (transport) Width, combat (transport) Height, combat (transport) Ground Pressure, MMP (nominal) Estimated Speed Estimated range Crew, number (roles) Main armament, caliber (ammo count ready/stowed) Secondary armament, caliber (ammo count ready/stowed) Vehicle designer’s notes: explain the thought process behind the design of the vehicle, ideas, and the development process from the designer’s point of view. Vehicle feature list: Mobility: 1. Link to Appendix 1- RFP spreadsheet, colored to reflect achieved performance. 2. Engine- type, displacement, rated power, cooling, neat features. 3. Transmission- type, arrangement, neat features. 4. Fuel- Type, volume available, stowage location, estimated range, neat features. 5. Other neat features in the engine bay. 6. Suspension- Type, Travel, ground clearance, neat features. Survivability: 1. Link to Appendix 1 - RFP spreadsheet, colored to reflect achieved performance. 2. Link to Appendix 2- armor array details. 3. Non-specified survivability features and other neat tricks- low profile, gun depression, instant smoke, cunning internal arrangement, and the like. Firepower: A. Weapons: 1. Link to Appendix 1- RFP spreadsheet, colored to reflect achieved performance. 2. Main Weapon- a. Type b. Caliber c. ammunition types and performance (short) d. Ammo stowage arrangement- numbers ready and total, features. e. FCS- relevant systems, relevant sights for operating the weapon and so on. f. Neat features. 3. Secondary weapon- Similar format to primary. Tertiary and further weapons- likewise. 4. Link to Appendix 3- Weapon system magic. This is where you explain how all the special tricks related to the armament that aren’t obviously available using Soviet 1961 tech work, and expand to your heart’s content on extimated performance and how these estimates were reached. B. Optics: 1. Primary gunsight- type, associated trickery. 2. Likewise for any and all other optics systems installed, in no particular order. C. FCS: 1. List of component systems, their purpose and the basic system architecture. 2. Link to Appendix 3- weapon system magic, if you have long explanations about the workings of the system. Fightability: 1. List vehicle features which improve its fightability and useability. Additonal Features: Feel free to list more features as you see fit, in more categories. Free expression zone: Let out your inner Thetan to fully impress the world with the fruit of your labor. Kindly spoiler this section if it’s very long. Example for filling in Appendix 1
Restricted: for Operating Thetan Eyes Only By order of Her Gracious and Serene Majesty Queen Diane Feinstein the VIII The Dianetic People’s Republic of California Anno Domini 2250 SUBJ: RFP for new battle tank 1. Background. As part of the War of 2248 against the Perfidious Cascadians, great deficiencies were discovered in the Heavy tank DF-1. As detailed in report [REDACTED], the DF-1 was quite simply no match for the advanced weaponry developed in secret by the Cascadian entity. Likewise, the DF-1 has fared poorly in the fighting against the heretical Mormonhideen, who have developed many improvised weapons capable of defeating the armor on this vehicle, as detailed in report [REDACTED]. The Extended War on the Eastern Front has stalled for want of sufficient survivable firepower to push back the Mormon menace beyond the Colorado River south of the Vegas Crater. The design team responsible for the abject failure that was the DF-1 have been liquidated, which however has not solved the deficiencies of the existing vehicle in service. Therefore, a new vehicle is required, to meet the requirements of the People’s Auditory Forces to keep the dream of our lord and prophet alive. Over the past decade, the following threats have presented themselves: A. The Cascadian M-2239 “Norman” MBT and M-8 light tank Despite being approximately the same size, these 2 vehicles seem to share no common components, not even the primary armament! Curiously, it appears that the lone 120mm SPG specimen recovered shares design features with the M-8, despite being made out of steel and not aluminum like the light tank. (based on captured specimens from the battle of Crater Lake, detailed in report [REDACTED]). Both tanks are armed with high velocity guns. B. The Cascadian BGM-1A/1B/1C/1D ATGM Fitted on a limited number of tank destroyers, several attack helicopters, and (to an extent) man-portable, this missile system is the primary Cascadian anti-armor weapon other than their armored forces. Intelligence suggests that a SACLOS version (BGM-1C) is in LRIP, with rumors of a beam-riding version (BGM-1D) being developed. Both warheads penetrate approximately 6 cone diameters. C. Deseret tandem ATR-4 series Inspired by the Soviet 60/105mm tandem warhead system from the late 80s, the Mormon nation has manufactured a family of 2”/4” tandem HEAT warheads, launched from expendable short-range tube launchers, dedicated AT RRs, and even used as the payload of the JS-1 MCLOS vehicle/man-portable ATGM. Both warheads penetrate approximately 5 cone diameters. D. Cascadian HEDP 90mm rocket While not a particularly impressive AT weapon, being of only middling diameter and a single shaped charge, the sheer proliferation of this device has rendered it a major threat to tanks, as well as lighter vehicles. This weapon is available in large numbers in Cascadian infantry squads as “pocket artillery”, and there are reports of captured stocks being used by the Mormonhideen. Warhead penetrates approximately 4 cone diameters. E. Deseret 40mm AC/ Cascadian 35mm AC These autocannon share broadly similar AP performance, and are considered a likely threat for the foreseeable future, on Deseret armored cars, Cascadian tank destroyers, and likely also future IFVs. F. IEDs In light of the known resistance of tanks to standard 10kg anti-tank mines, both the Perfidious Cascadians and the Mormonhideen have taken to burying larger anti-tank A2AD weaponry. The Cascadians have doubled up some mines, and the Mormons have regularly buried AT mines 3, 4, and even 5 deep. 2. General guidelines: A. Solicitation outline: In light of the differing requirements for the 2 theaters of war in which the new vehicle is expected to operate, proposals in the form of a field-replaceable A-kit/B-kit solution will be accepted. B. Requirements definitions: The requirements in each field are given in 3 levels- Threshold, Objective, and Ideal. Threshold is the minimum requirement to be met; failure to reach this standard may greatly disadvantage any proposal. Objective is the threshold to be aspired to; it reflects the desires of the People’s Auditory Forces Armored Branch, which would prefer to see all of them met. At least 70% must be met, with bonus points for any more beyond that. Ideal specifications are the maximum of which the armored forces dare not even dream. Bonus points will be given to any design meeting or exceeding these specifications. C. All proposals must accommodate the average 1.7m high Californian recruit. D. The order of priorities for the DPRC is as follows: a. Vehicle recoverability. b. Continued fightability. c. Crew survival. E. Permissible weights: a. No individual field-level removable or installable component may exceed 5 tons. b. Despite the best efforts of the Agriculture Command, Californian recruits cannot be expected to lift weights in excess of 25 kg at any time. c. Total vehicle weight must remain within MLC 120 all-up for transport. F. Overall dimensions: a. Length- essentially unrestricted. b. Width- 4m transport width. i. No more than 4 components requiring a crane may be removed to meet this requirement. ii. Any removed components must be stowable on top of the vehicle. c. Height- The vehicle must not exceed 3.5m in height overall. G. Technology available: a. Armor: The following armor materials are in full production and available for use. Use of a non-standard armor material requires permission from a SEA ORG judge. Structural materials: i. RHA/CHA Basic steel armor, 250 BHN. The reference for all weapon penetration figures, good impact properties, fully weldable. Available in thicknesses up to 150mm (RHA) or 300mm (CHA). Density- 7.8 g/cm^3. ii. Aluminum 5083 More expensive to work with than RHA per weight, middling impact properties, low thermal limits. Excellent stiffness. Fully weldable. Available in thicknesses up to 100mm. Mass efficiency vs RHA of 1 vs CE, 0.9 vs KE. Thickness efficiency vs RHA of 0.33 vs CE, 0.3 vs KE. Density- 2.7 g/cm^3 (approx. 1/3 of steel). For structural integrity, the following guidelines are recommended: For light vehicles (less than 40 tons), not less than 25mm RHA/45mm Aluminum base structure For heavy vehicles (70 tons and above), not less than 45mm RHA/80mm Aluminum base structure. Intermediate values for intermediate vehicles may be chosen as seen fit. Non-structural passive materials: iii. HHA Steel, approximately 500 BHN through-hardened. Approximately twice as effective as RHA against KE and HEAT on a per-weight basis. Not weldable, middling shock properties. Available in thicknesses up to 25mm. Density- 7.8g/cm^3. iv. Glass textolite Mass efficiency vs RHA of 2.2 vs CE, 1.64 vs KE. Thickness efficiency vs RHA of 0.52 vs CE, 0.39 vs KE. Density- 1.85 g/cm^3 (approximately ¼ of steel). Non-structural. v. Fused silica Mass efficiency vs RHA of 3.5 vs CE, 1 vs KE. Thickness efficiency vs RHA of 1 vs CE, 0.28 vs KE. Density-2.2g/cm^3 (approximately 1/3.5 of steel). Non-structural, requires confinement (being in a metal box) to work. vi. Fuel Mass efficiency vs RHA of 1.3 vs CE, 1 vs KE. Thickness efficiency vs RHA of 0.14 vs CE, 0.1 vs KE. Density-0.82g/cm^3. vii. Assorted stowage/systems Mass efficiency vs RHA- 1 vs CE, 0.8 vs KE. viii. Spaced armor Requires a face of at least 25mm LOS vs CE, and at least 50mm LOS vs KE. Reduces penetration by a factor of 1.1 vs CE or 1.05 vs KE for every 10 cm air gap. Spaced armor rules only apply after any standoff surplus to the requirements of a reactive cassette. Reactive armor materials: ix. ERA-light A sandwich of 3mm/3mm/3mm steel-explodium-steel. Requires mounting brackets of approximately 10-30% cassette weight. Must be spaced at least 3 sandwich thicknesses away from any other armor elements to allow full functionality. 81% coverage (edge effects). x. ERA-heavy A sandwich of 15mm steel/3mm explodium/9mm steel. Requires mounting brackets of approximately 10-30% cassette weight. Must be spaced at least 3 sandwich thicknesses away from any other armor elements to allow full functionality. 81% coverage (edge effects). xi. NERA-light A sandwich of 6mm steel/6mm rubber/ 6mm steel. Requires mounting brackets of approximately 10-30% cassette weight. Must be spaced at least 1 sandwich thickness away from any other armor elements to allow full functionality. 95% coverage. xii. NERA-heavy A sandwich of 30mm steel/6m rubber/18mm steel. Requires mounting brackets of approximately 10-30% cassette weight. Must be spaced at least 1 sandwich thickness away from any other armor elements to allow full functionality. 95% coverage. The details of how to calculate armor effectiveness will be detailed in Appendix 1. b. Firepower i. 2A46 equivalent tech- pressure limits, semi-combustible cases, recoil mechanisms and so on are at an equivalent level to that of the USSR in the year 1960. ii. Limited APFSDS (L:D 15:1)- Spindle sabots or bourelleted sabots, see for example the Soviet BM-20 100mm APFSDS. iii. Limited tungsten (no more than 100g per shot) iv. Californian shaped charge technology- 5 CD penetration for high-pressure resistant HEAT, 6 CD for low pressure/ precision formed HEAT. v. The general issue GPMG for the People’s Auditory Forces is the PKM. The standard HMG is the DShK. c. Mobility i. Engines tech level: 1. MB 838 (830 HP) 2. AVDS-1790-5A (908 HP) 3. Kharkov 5TD (600 HP) ii. Power density should be based on the above engines. Dimensions are available online, pay attention to cooling of 1 and 3 (water cooled). iii. Power output broadly scales with volume, as does weight. Trying to extract more power from the same size may come at the cost of reliability (and in the case of the 5TD, it isn’t all that reliable in the first place). iv. There is nothing inherently wrong with opposed piston or 2-stroke engines if done right. d. Electronics i. LRFs- unavailable ii. Thermals-unavailable iii. I^2- limited 3. Operational Requirements. The requirements are detailed in the appended spreadsheet. 4. Submission protocols. Submission protocols and methods will be established in a follow-on post, nearer to the relevant time. Appendix 1- armor calculation Appendix 2- operational requirements Addendum 1 - more armor details Good luck, and may Hubbard guide your way to enlightenment!
O-I 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. 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-caliber 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, labeled "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. 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. 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-millimeter-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 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 kilometers 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 maneuvering 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 canceled 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. 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. 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, totaling 16 individual wheels. Data Sheet Sources - O-I documentation, Finemolds - O-I project report notebook 1,2,3,4,5, and 6 (Finemolds) - JP Tank Perfect Guide - 日本の戦車 原乙未生 (Hara's book) (Old sources) - 帝国陸軍陸戦兵器ガイド1872-1945 - 日本陸軍の火砲 野戦重砲 - 戦車と戦車戦 - 太平洋戦争秘録 日本・秘密兵器大全 ---------------------- Since the article Soukou and Daigensui wrote long ago is filled with inconsistencies and errors, decided to make something thats actually accurate to the reports. Wrote it on Google Docs initially, posted it to WT earlier. Will be present on Ritas blog and eventually Wikipedia.