英文原作（译）者：tank Archives的Peter,2019/3/30星期六

https://www.tankarchives.ca/2019/03/modernization-on-paper.html

俄文原作者：Yuri Pasholok,2018/6/11

https://warspot.ru/12111-modernizatsiya-na-bumage

个人授权翻译

这位老兄【指英文作（译）者】写了很多二战坦克的文章，还出了书，确定不去看看吗？

Modernization on Paper 活在图纸中的现代化改造案

Technical progress moves in giant leaps during large wars. This rule applied to nearly all types of weapons and armament during WWII, including tanks. Every year of war raised the bar of requirements, and even the newest fighting machines quickly became outdated.

大战总是会导致技术进步，这条适用于包括坦克在内的几乎所有二战中的武器。年复一年的战争在不断提高对装备的要求，即使是最新式的武器也往往会在不久后变得过时。

The heavy IS-1 tank was created as a response to the Tiger, but was obsolete by the time it entered production. The IS-2 that came to replace it had a much more powerful gun, but it too would need to be replaced soon. Today let us remember the tanks that were supposed to replace the IS-2 in 1944. Not a single one was ever built in metal, but work on these projects resulted in the creation of the IS-2 with straight upper front hull armour and the IS-3.

IS-1重型坦克是作为对虎式坦克的回应而诞生的，但它早在投产之时便已经落伍了。结果，鸟枪换炮的IS-2出现了，但它迟早也会沦落到需要被替换的一天。今天，让我们来康康那些计划在1944年取代IS-2的方案。这些方案全部都顶多只有木制模型，但这些方案最终催生了拥有一体式首上的IS-2以及IS-3。

Grassroots initiative基层之声

The first battles of the IS-1 tank showed that the armour of new Soviet heavy tanks does not entirely meet the modern requirements for battle. On February 19th, 1944, tanks of the 13th Guards Heavy tank Regiment came under fire from Panther tanks. The front armour of the IS-1, built to withstand fire of the 88 mm KwK 36, could be penetrated by the 75 mm KwK 42. Two tanks burned up and three more were knocked out.

IS-1坦克的首战表明，这种苏联新重型坦克的装甲并不能很好的适应现代战场环境的需要。在1944年2月19日，第13近卫重型坦克团的IS-1遭到了黑豹坦克的攻击。本应能承受Kwk 36 88mm炮攻击的IS-1正面装甲居然被Kwk 42 75mm炮轻易洞穿，导致2辆坦克起火，另有3辆坦克被击毁。

Casting defects played a role in this result, but the main reason was that the armour was simply insufficient. This was the conclusion reached by Engineer-Major A.I. Shamin, senior assistant to the Chief of the NIBT Proving Grounds Experimental Department, who was attached to the 13th Guards Heavy tank Regiment. He critiqued the shape of the front hull. The "step" in the armour and driver's vision port weakened the armour. Shamin's conclusions were included in the general conclusions to NIBT trials of IS-1 and IS-2 tanks built in January-February 1941. The first point in the summary was "the armour protection of the turret and front hull does not match the power of the tank's armament".

这个结果的部分原因应“归功”于铸造装甲的缺陷，但最大的问题还是单纯的厚度不够。该结论由少校工程师A·I·沙明得出（他还是NIBT试验场实验部主任的高级助理，并隶属于第13近卫重型坦克团）。他抨击了阶梯型的首上，认为这样的首上形状和驾驶员窗口严重削弱了防护。沙明的建议被放进了NIBT对于1944年【译注：俄语原文是1944年，英版翻译有误】1月至2月间生产的IS-1和IS-2坦克的实验结论中。报告总结的第一条便是：“该车的防护水平完全不能于其强大的火力相匹配”。

A proposal was made to improve protection of the hull and turret by improving the slope and quality of the armour. The T-34's hull shape was taken as a starting point. The NIBT proving grounds proposed changing the upper front hull armour. The thickness would remain at 120 mm, but the armour would be rolled, and the angle would be 30 degrees from horizontal. This would offer reliable protection from the 88 mm Pak 43 L/71 gun used on the Ferdinand tank destroyer. The designers considered the trials of this tank and another trophy from the Battle of Kursk, the Panther. Its 80 mm plate angled at 35 degrees from horizontal offered better protection than the IS-2's "step". The 85 mm gun couldn't penetrate this armour at point blank range, and the Panther itself could penetrate it at only 200 meters.

一个通过改善装甲质量和增大倾斜角度来提升车体和炮塔的防护的方案被提出。NIBT提出要参考T-34首上的形状，在厚度保持为120mm不变的情况下将水平角度降至30°，这样便可以在面对斐迪南坦克歼击车上的Pak 43 88mm火炮时有效保护坦克。同时，设计师还参考了另一个库尔斯克战役中缴获的战利品——豹式D型坦克，其80mm厚的装甲与水平面成35度角【译注：应为垂直面而非水平面，而且参加库尔斯克战役的豹式D型首上只有60mm厚，80mm是后续的豹A和豹G的厚度，因此该黑豹可能既不是缴获自库尔斯克战役，又不是D型】，提供的防护效果远好于IS-2的阶梯式首上。85mm炮即使在近距离也无法击穿，而就算是黑豹自身也需要靠近到200m以内才能将其击穿。

The results of firing on the Panther with a Pak 43 installed in a Hornisse SPG were also interesting. At a range of 600 meters the shell knocked out a 300x250 mm fragment and ricocheted.

用犀牛上的Pak 43射击豹式D型的测试结果也很有趣。在600m距离上，炮弹打出了一块300x250mm的破片并跳弹了。

The NIBT proving grounds specialists also proposed improving the side armour. The thickness was reduced from 90 to 75 mm, but rolled plates installed at 45 degrees would be used. The proposal also included increasing the front turret armour to 200 mm and the sides of the turret to 150 mm. The list of improvements also included replacing the 122 mm D-25 gun with a 100 mm gun that had a higher rate of fire. All of these proposals were grassroots initiatives.

NIBT试验场的专家还建议将侧装甲从90mm削减至75mm，但把倾斜角度改为45°并使用轧制钢板。此外他们还建议将炮塔正侧面装甲分别增至200mm和150mm厚，以及用射速更高的100mm炮取代122mm炮。所有的这些建议均来自基层。

From each according to ability各显神通

Precursor work to modernizing the IS series of tanks began in the summer-fall of 1943. Initially, the armament was the only thing that was improved. Work was aimed in three directions:

对IS系列坦克现代化改造的前期工作始于1943年的夏秋之交。最初，该项目只包括武备的更换，有三条发展路线：

1. Improving the firepower of the 85 mm gun提升85mm炮的火力

2. Improving the firepower of the 122 mm gun提升122mm炮的火力

3. Creating tank and SPG 100 mm guns新建使用100mm炮的坦克和自行火炮

In the first and third case, the work reached the prototype stage.

其中的第一项和第三项进度到了原型车阶段。

More radical improvements to the tank's characteristics were also suggested. A draft report by Major-General Fedorenko to Stalin dated September 5th, 1943, contained a suggestion to increase protection of the IS-2 tank at the cost of raising the weight to 55-60 tons. This proposal was crossed out, but nature abhors a vacuum. 

他们还建议彻底更新坦克的特性。费多连科少将在1943年9月5日给斯大林提交了一份报告，建议将IS-2坦克的吨位增至55至60吨以大幅增强其防护能力。该方案被枪毙，但这一“生态真空”不可能永远持续下去。

On September 28th, 1943, factory #627 proposed the TET heavy tank project with an electric transmission. The first variant weighed 50-52 tons, its front armour reached 150 mm, and its top speed was 35 kph. The A-19 gun (meaning the D-25) would be its main armament. The second variant was even more monstrous: its mass was 64-66 tons and it had 180 mm of front armour.

1943年9月28日，627号厂提出了电传动的TET重型坦克方案。第一版重52至54吨，正面装甲厚150mm，最高速度35km/h，主炮采用A-19火炮（也就是后来的D-25）；第二版甚至更离谱：重64至66吨，正面装甲180mm。

The GBTU composed requirements for a new heavy tank in late November of 1944. The mass would be 55 tons. Its crew would consist of 5 men. The front of the hull armour would be 200 mm, front of the turret would be 160 mm. The tank would either be armed with a 122 mm gun or 152 mm gun-howitzer. An 800-1000 hp engine would propel this monster. The transmission would be in the front. A planetary gearbox would be used. An electrical transmission was considered, but work never progressed past the draft stage.

装甲兵总局（GBTU）在1943年11月下旬【译注：从下文来看，该指标应该是在1943年11月提出的，而俄语原文也写的是1943年，英语作者写44年是笔误】提出了新重型坦克的技术指标：总重55吨，5人车组，车体正面厚200mm、炮塔160mm，配备一门122mm炮或152mm榴弹炮，引擎动力为800至1000马力，前驱、考虑使用电传动。这一怪物最终没有活过草案阶段。

A tendency to split work evolved out of the escalating rivalry between factory #100 and ChKZ. ChKZ's SKB-2 design bureau began working on a new heavy tank in the summer of 1943, which in many ways matched the aforementioned requirements for a heavy tank. unlike the KV-85 modernization, for which Zaltsmann and Makhonin received a dressing down from Malyshev, the People's Commissar of tank Production approved this initiative. The 56 ton "K tank" turned into the Object 701. This defined two different approaches: replacement of the IS-2 and its modernization.

随着100号厂和车里雅宾斯克厂【译注：Челябинский Кировский Завод 或ChKZ，即车里雅宾斯克基洛夫工厂】之间的竞争趋于白热化，两家开始趋向于各搞各的，车里雅宾斯克厂的SKB-2设计局于1943年夏开始研究一款新型重型坦克，它在许多方面都符合上一段中对新重型坦克的要求。与KV-85的现代化不同，萨尔茨曼和马霍宁都遭到了马雷舍夫的批评，而坦克生产人民委员会则批准了这一举措。这样一来，56吨的“K坦克”摇身一变成了701工程。因此，出现了两条路线：搞一个取代IS-2的坦克以及对IS-2进行现代化改造。

This split was one of a few strange occurrences that took place in 1944 in Chelyabinsk. GKO decree #5582ss "On the production of a new heavy tank at the Kirov factory" signed on April 8th signalled an escalation of the situation. It describes the production of two experimental Object 701 tanks, but the third item of the document mentions a completely different vehicle.

这次分裂可以说是1944年车里雅宾斯克厂少有的怪事之一。国防部在4月28日签署了5582ss号“关于在基洛夫工厂生产新型重型坦克”的法令标志着事件的进一步升级。它描述了两辆701工程的实验型号的生产，但文件的第三项还提到了一款完全不同的坦克。

"The NKTP (comrade Malyshev), director of the Kirov factory (comrade Zaltsmann), and chief engineer comrade Kotin must concentrate their attention on the improvement of the design and quality of the IS tanks and SPGs.

Within 3 months, perform the necessary work on increasing the IS tanks' armour protection, improvement of the transmission and suspension, using experience from new heavy tanks for modernization of the IS. "

“重工业人民委员部（马雷舍夫同志）、基洛夫工厂厂长（萨尔茨曼同志）、总工程师科京同志必须专注于改进IS坦克和自行火炮的设计和生产质量问题。

在3个月内，通过必要的工作，增厚IS坦克的防护，改进其传动和悬挂系统，用在设计新坦克时获得的经验来改进IS坦克。”

This decree morphed into NKTP order #226ss signed on April 13th, 1944. The requirements for a deep modernization of the IS-2 were finally formed by May 19th, 1944. The list of improvements numbered 20 items. Some of them were based on the Object 701. The radiators, cooling system linkage, turret traverse mechanism, and turret ring design were taken from this tank. The front hull, 90 mm rolled armour or 100 mm cast, was based on the front armour of the Object 701. The turret design was also based on this tank: the commander's cupola and mechanism for extracting the gun through a hatch in the roof were the same. The exhaust pipes were moved to the rear plate, like on the T-34. This solution fully prevented exhaust fumes from entering the air intakes.

该法令最终演变为重工业人民委员部在1944年4月13日签发的226ss号命令。对IS-2进行深度现代化改造的指标最终在同年5月19日被确定下来。改进清单多达20项，其中一些来自701工程：散热器、冷却系统连杆、炮塔旋转系统、炮塔座圈。车体正面（90mm轧制装甲或100mm铸造装甲）也基于701工程。还有炮塔：车长指挥塔和通过炮塔顶部舱口取出火炮的机构是相同的。排气管如T-34一般被移到了车尾，以杜绝废气涌入进气口。

Interestingly enough, the design of this modernization was expedited not by ChKZ, but by factory #100. A draft project of the modernization of the IS-2 designed at this factory was presented on April 18th. The modernized tank weighed 46-47 tons. The hull was completely redone. Its shape was more reminiscent of a flying saucer. The hatch in the front of the hull was removed. The front and side armour was 120 mm thick. The turret, whose front was now 150 mm thick, was also radically redesigned.

有趣的是，这种现代化的进程却是由100号厂，而非车里雅宾斯克厂来推动的。该厂设计的IS-2现代化改造方案递交于4月18日。改造后的坦克全重46至47吨，车体被完全重做且看起来更像飞碟。车体正侧面的装甲厚达120mm，前部的舱口也被移除。炮塔则进行了全面的重新设计，正面厚达150mm。

The suspension was also altered. The tank was supposed to receive large diameter road wheels. The armament consisted of either a D-25T or a D-10T gun. A coaxial GVG (future SG-43) machinegun was used instead of a DT. No details on the engine or transmission are known, but two types of planetary transmissions were tested in early 1944: one designed at the Bauman Technical University, one desigend at factory #100. The engine is not known, but the fact that the tank's top speed was 50 kph hints at the fact that it would not have been a V-2-IS.

坦克的悬挂也进行了修改，他们准备为其换上更大直径的负重轮。武备方面则同时考虑了D-25和D-10火炮，同轴机枪则为GVG机枪（即后来的SG-43），以取代DT机枪。对于发动机或变速器的改进则语焉不详，但已知在1944年年初测试了两种行星变速器：一种来自鲍曼技术大学，另一种则来自100号厂。发动机型号未知，但从其最高时速50km的表现来看，这绝不可能是V2-I-S。

This project was not the only modernization developed at factory #100. Requirements for a heavy tank approved in November of 1943 were not forgotten. Revised requirements were introduced on March 22nd, 1944, which set the mass at 55-56 tons. The numbers for armour thickness were gone: the requirement was now only to protect the tank from the guns of the Tiger, Panther, and Ferdinand. The side armour would have to be immune at a range of 500 meters or greater. The tank would be armed with a 122 mm gun with a muzzle velocity of 1000 m/s and carry 30-40 rounds of ammunition. A 1000 hp engine would give the tank a top speed of 40 kph, or 24-26 kph on a dirt road. The tank would be equipped with an electrical or mechanical transmission. In the case of the latter, a 6-speed planetary gearbox with a 2-stage turning mechanism would be used.

该项目并不是100号厂唯一一个现代化改进项目，他们并没有忘记1943年11月的那个重型坦克指标。1944年3月22日，指标被修改了：车重55至56吨；装甲厚度不限，但其必须能够免遭虎式、黑豹或斐迪南击穿（侧面要做到在500m外免疫这三种火炮的攻击）；主炮使用一门初速达到1000m/s的122mm火炮，备弹量30至40发；引擎动力为1000马力，最大速度为40km/h，最大越野速度为24至26km/h；传动系统既可选用机传，也可使用电传，如果要用机械传动的话，将搭配上带二级转向机构的六速行星齿轮变速箱。

These requirements were realized in the draft project designed under the direction of N.F. Shashmurin. The tank had a turret in the rear. The hull housed the driver and radio operator. The design of the turret, suspension, and partially the hull were used as starting points for the development of a less radical modernization of the IS-2.

这些需求在N·F·沙什姆林的主持下在设计图上成真了。坦克的炮塔后置把杠二玩明白了属实是，驾驶员和机电员位于车体。该方案的炮塔、悬挂和部分车体的设计被用作不那么激进的IS-2现代化改造方案的起点。

The draft project that is sometimes called IS-2M was proposed in early April of 1944. It was forgotten quite quickly, but the 46 ton IS-2 modernization reached the wooden scale model stage. The development of the modernization ended here.

这一方案（有时被称作IS-2M）于1944年四月初被提出【译注：不要跟50年代末的IS-2M搞混】，并被迅速遗忘，但46吨级的IS-2现代化改造方案已经进到了木制模型阶段，并且将永远的止步于此。

In April of 1944 factory #100 also began working on a new heavy tank project known as the IS-6. It was done in strict secrecy, and even some members of the factory management were unaware of its existence. The military representative at factory #100 even sent an official complaint to the GBTU. Work on the IS-6 incorporated elements of the modernized IS-2 project, and spelled doom for both the 46 ton IS-2 and Shashmurin's tank.

在1944年4月，100号厂开始了另一项重型坦克项目，即IS-6。该车的设计在高度保密中进行，就连一些工程管理层的成员都对其的存在一无所知，该厂的军方代表还为此向装甲兵总局进行了正式的投诉。IS-6的设计工作中含有不少IS-2现代化改造方案中的元素，这也为沙什姆林的坦克带来了灭顶之灾。

However, the situation remained odd. ChKZ and its neighbours were working on not only two brand new tanks, but two types of IS-2 modernization: large and small scale.

诡异的情况仍在持续。车里雅宾斯克厂及其邻居不仅在开发两种全新的坦克，还在同时推进一大一小两种IS-2的现代化改造方案。

The situation with the engine is also worth mentioning. An order was given to increase the power of the V-2-IS engine back in 1943. A more powerful engine was also designed for the Object 701. Work in this direction moved far past requirements and draft projects. Three engines were designed based on the V-2: the V-11 by factory #75, V-14 by factory #76, and V-16 by factory #77. Of those, only the V-11 was mass produced, and even then only in 1945. Instead of the required 700 hp, it produced the same 520 hp as the V-2-IS.

引擎的情况也值得一提。早在1943年上面便要求增强V-2-IS引擎的动力。一台更强大的发动机被设计给了701工程。该方向的开发进度也将设计指标远远地抛在了后面，并产生了三台不同的成果：75号厂的V-11、76号厂的V-14和77号厂的V-16。在其中，只有V-11在1945年这唯一一年被大规模量产，但其输出功率与V-2-IS一致，只有520马力而非要求的700马力

The Kazakh Agricultural Institute (Alma-Ata) developed another engine for the IS-2, a very unique one. A steam engine, originally meant for the KV, took too long to develop, and was later designed for the IS. This development was discussed several times, and two variants with different dimensions were proposed. The engine was never produced, even though the funds for it were allocated several times.

哈萨克斯坦农业研究所（阿拉木图）为IS-2研发了另一种独特的发动机——一款蒸汽机，本是为KV坦克设计的，但开发的时间太长，便转为IS坦克所用。该方案被一再讨论，并提出了两种尺寸不同的型号。尽管为其多次注资，但该发动机却从未投入生产。

Beefing up the archives匿于档海

While factory #100 had enough time to develop and subsequently abandon its own IS-2 modernization project, ChKZ's SKB-2 had its own issues. For starters, they had to improve the design of the tank while its production was ramping up. Don't forget that the development of the Object 701 also had high priority. GKO decree #5583ss created a special group of 25-30 engineers and 10-15 technologists at the factory, whose job was the support and production of new heavy tanks. It's not surprising that the large scale modernization of the IS-2 was considered secondary. Only three months were allocated to this task.

100号厂有足够的时间来开发并放弃其IS-2改造方案，但车里雅宾斯克厂的SKB-2局却有着自己的问题。首先，他们必须在设计新坦克的同时保证现有坦克的增产——别忘了701工程的开发一样有着很高的优先级。国防部5583ss号命令使得工厂组建了一支由25至30名工程师和10至15名技术人员组成的特殊小组，他们的任务是支持新重型坦克的生产。而IS-2的改进则被认为是次要的，这并不奇怪，因为上级只给了他们3个月的时间来处理此事。

Full fledged work on a large scale modernization of the IS-2 began only in the summer of 1944. This didn't stop the designers from reusing a number of solutions on the production tank. The most important was the introduction of a straight upper front hull section in August of 1944. The minimal distance at which the Pak 43 could penetrate the UZTM production welded hull increased to 575 meters, and the cast 100 mm front could only be penetrated at 255 meters. A downside was the reduced visibility from the driver's station and the weak spot formed by the Object 701 type observation device, but there were more advantages than drawbacks.

对IS-2的大规模改进工程仅在1944年持续了一个夏天，但这并未阻拦设计师们在坦克的生产上重复使用许多解决方案，其中最重要的一点是一体式首上。这样一来，由乌拉尔厂【译注：Uralmash或UZTM，即乌拉尔机械厂】生产的铸造型首上车体对Pak 43的免疫距离增至575m，而100mm的轧制首上免疫距离更是达到了255m，带来的缺点是驾驶员视界缩小，且移植自701工程的观测设备依旧是一个弱点。但无论如何，这些改动无疑是利大于弊。

The GKO decree proposed that large scale modernization work would be immediately implemented in production. No prototypes would be built. As a result, a very precarious situation formed in the fall of 1944. A special request was made to L.P. Beria asking for authorization to produce IS-2 and ISU-152 prototypes with significant changes of their design. Work on the modernized tank stopped for some time, and was only limited to the creation of a wooden model of the turret. After permission was granted, work began once more, but it was clear that the factory will not meet its deadline. Work on improving the Object 701 had an adverse effect on this work, as the design needed a lot of work. Blueprints for the modernized IS-2 were only ready by the end of August of 1944. Kirov factory received the hull of the modernized tank on the 31st, and assembly was performed in September. The modernized ISU-152 was built in parallel.

国防部命令将这些改动在不建造任何原型车的情况下立刻投产，结果就是在1944年秋形成了一种非常不稳定的局面。L·B·贝利亚收到了一项特殊的请求，要求他授权制造进行了大规模现代化改造后的IS-2和ISU-152原型车。为此，现代化坦克的项目，除了制造木制炮塔模型外，被暂停了一会。在得到了许可后，项目继续，但很明显的此时工厂已经无法将其按时完成。由于改进701工程设计的项目占用了大量资源，其显然应该对此负部分责任。改进后的IS-2蓝图直到1944年8月末才准备就绪，基洛夫工厂直到31日才收到了车体并在9月对其进行了组装，ISU-152改进项目的进度则与之相近。

Strangely enough, no photos of the modernized IS-2 or modernized ISU-152 survive to this day. Only scraps of documentation and correspondence are available. The development of this vehicle considered not only the requirements made in April-May of 1944, but also experience in combat and experience with building the modernized IS-2 hull. The large scale modernization of the IS-2 was perfomed with this type of tank as the starting point.

奇怪的是，如今没有一张改进后的IS-2或ISU-152的存世照片，它们只存活于文档和信件中的只言片语间【译注：这里大概指的是二者的原型车】。这些车辆不仅考虑到了1944年四五月间的设计指标，还结合了战场上的实际经验和建造改进型IS-2车体的经验。IS-2的大规模改进正是以此为起点的。

The biggest changes were made to the engine compartment. In addition to a T-34 type exhaust system, the modernized hull also had a significantly different air intake system, inspired by those used on the Object 701 and Panther. The fuel system was radically redesigned. The fuel tanks were moved from the fighting compartment to the engine compartment and became interchangeable. The former location of the fuel tanks was now occupied by new batteries. The total number increased from 2 to 4. The turret was also redesigned. It was now similar to the one designed at factory #100. The gun was removed through a hatch in the turret. This allowed the gun mount to be redesigned to be more robust. The turret front was 130 mm thick, which increased its resilience. The turret ring, commander's cupola, and ventilation fan were also changed.

最大的变化在发动机舱。除了使用T-34的排气系统外，改进后的车体还有一个明显不同的进气系统，其灵感来自于701工程和黑豹坦克上的同类设备。燃油系统得到了重做，油箱从战斗室移到了发动机舱并变得可以进行互换。原来油箱的位置现在被电池占据，总数也翻了一倍，达到了4个。炮塔也被重新设计了，现在其更接近于100号厂的方案：火炮是通过炮塔顶部的一个舱口取出的，这使得炮架得到了重新设计，变得更坚固了；炮塔正面厚达130mm，增强了其防弹能力；炮塔座圈、车长指挥塔和换气扇也进行了更换。

The GBTU prepared a list of 12 changes to the design in October of 1944. However, they were never implemented. ChKZ began working on another variant of modernization in the fall of 1944. It received the index Kirovets-1 and blueprints number 703. The index IS-3 was assigned to it in trials. Additional work at factory #100 began in the fall of 1944. A project internally called IS-2U under the direction of A.S. Yermolayev began in November of 1944. L.E. Sychev was the chief engineer.

装甲兵总局在1944年10月拟出了一份共计12项变动的设计清单，但它们从未被应用。车里雅宾斯克厂在1944年秋开始了另一项改进工作，该方案得名基洛韦茨-1（IS-3），代号703工程。同时，100号厂开启了另一个项目。在A·S·叶尔莫拉耶夫的指导下，被称为IS-2U的项目于1944年11月揭开帷幕，总工程师为L·E·谢切夫。

The IS-2U looked like a halfway point between the IS-2 with a straight front hull and ChKZ's deep modernization. The turret was also similar, but had weaker armour than the one designed in the spring of 1944. The rear was almost the same as on the IS-2.

IS-2U看起来像是一体式首上IS-2和车里雅宾斯克厂的深度改进型IS-2的折中。炮塔长得很像，只是防护要比1944年春设计的那款更弱，车体后部看起来跟IS-2几乎一模一样。

The most interesting part of the project was the front of the hull, developed by chief designer V.I. Tarotko. It had a unique "pike nose" shape. The upper front armour was sloped at 25 degrees to horizontal and consisted of two parts. This shape of the front armour allowed the placement of a driver's hatch in the front of the hull. Unlike the Kirovets-1 or the experimental modernized IS-2, the IS-2U was never built. However, the project had a significant influence on Soviet tank design. The "pike nose" was used on later tanks, the first of which was the mass production IS-3. Tarotko also used it on the reworked Object 252, which evolved into the Object 257.

该项目最有意思的是由总设计师V·I·塔罗卡设计的首上，其拥有一个独特的“派克鼻子”形状。首上与水平面呈25°倾斜，包括了两个部分，前装甲的凸出部分允许将驾驶员舱口放在更前的位置驾驶员：WTM。与基洛韦茨-1或IS-2改进型的原型车不同，该车从未被制造出来，但却对未来的苏联坦克产生了深远的影响，其中的第一个便是大量生产的IS-3。塔罗卡还将这一设计运用到了重置的252工程上，并最终发展成了257工程。