Thursday, 8 August 2013

World of Tanks History Section: T-60

The Great Patriotic War that started on June 22nd, 1941 made serious changes to the development of Soviet tank manufacturing. The first days of the war saw the cutting of a series of development programs, and even a number of vehicles already in mass production.

According to the decision of the USSR SNK, on June 25th, 1941, Ordzhonikidze factory #37 NKSM in Moscow was to cease producing half-armoured T-20 "Komsomolets" artillery tractors and amphibious T-40 tanks on August 1st. Instead, they were to assemble T-50 tanks. The Ordzhonikidze factory in Podolsk would supply hulls and turrets. In total, up to 50 organizations in Moscow and the Moscow area were tasked with producing components for the T-50.

The decision to replace the T-40 with the T-50 seemed logical and reasonable. Amphibious scout tanks were not produced in massive quantities. They were meant to supplement more numerous armoured cars. The amphibious tank with only 13 mm of armour and a DShK machine gun seemed inferior to the T-50, with its thick, anti-gun armour and 45 mm cannon. The child of factory #174 was meant to also replace the T-26, and become one of the Red Army's most numerous tanks. By June 1941, production began. Amid the harsh losses of the start of the war, it seemed that T-50s would be needed in huge numbers.

The conditions for the T-50 were perfect, but an order is one thing, and reality is another. Factories were not ready to produce it. The tank ended up being complicated even for #174. Due to this, the start of production was delayed by several months. Factory #37, which previously assembled amphibious tanks from automotive components, had an even more difficult time. The Moscow vehicles did not exceed 5 tons, while the new Leningrad tank weighed 14 tons. The V-4 diesel engines posed another problem. Factory #75 NKSM (Kharkov) did not set up their production. As a result, the chances of mass producing the T-50 in 1941 dropped to zero. If factory #37 followed orders and dropped production of the T-40, no new light tanks would be produced at all. Thankfully, the management of factory #37, especially its construction bureau, headed by Nikolai Aleksandrovich Astrov, fully realized the capabilities of the factory. In order to assemble a 14 ton tank, the tools of the factory must be upgraded, and there was a lack of heavy cranes to do so. Formally, factory #37 did not refuse the order to produce a T-50, and was even developing an amphibious tank on its chassis. At the same time, in utter secrecy, the factory's construction bureau was developing a tank that was a simplified version of the T-40. In July of 1941, a letter was sent by N.A. Astrov and the factory military representative, V.P. Okunev. This letter, addressed to Stalin, described the impossibility of producton of the T-50 at factory #37, and suggested a replacement that could be produced in large quantities: a small tank based on the T-40.

The letter was delivered to Stalin on that same night, and piqued his curiosity. The next morning, the deputy SNK chief and People's Commissar of Medium Manufacturing Malyshev arrived at the factory. After evaluating the situation and hearing the claims of the project initiators, he wrote a letter to Molotov on July 14th, in which he approved the project.

The new tank, indexed T-60 (or 030 in internal factory communications) was a non-swimming version of the T-40. Turns out that T-40 hulls and turrets manufactured in Podolsk were very complicated, especially turrets, made entirely out of cemented armour. A large amount of hull defects delayed production. A switch to homogeneous armour partially solved that problem. A simplified hull was necessary, especially with the GKO order #222 "On manufacturing of 10 thousand light tanks", which increased the amount of factories that produced the T-60.

On July 23rd, NKSM order #360ss ordered factory #37 to develop a simplified T-60 hull and turret. Two days later, the factory had a technical meeting on the issue of GAZ and HTZ producing T-60 tanks.

Instead of a simplified T-40, HTZ and GAZ received blueprints for a radically different vehicle. Meanwhile, factory #37 was producing the initial T-60, due to production quotas and an overload of the Podolsk Ordzhonikidze factory. The result was a tank called the T-30, which is worthy of its own article. The "030" was not called "T-60" for long. At the end of July, the tank was first officially referred to as T-30, and by the end of August, it is widely referred to as such. The tank produced at HTZ and GAZ had the factory index "060".

The index T-70 was used rarely, but enough to confuse some historians. The tank is called "T-60 with a simplified hull", "T-60M", or just "T-60". The last name was firmly attached to the new tank by the fall of 1941, but even in 1942, some factories still call it "T-70" or "T-60M".

It is interesting to note that the army accepted both 030 and 060 before construction of experimental prototypes. With 030, it is not as surprising, since it was effectively a T-40 with a simplified armour scheme. Development of blueprints for this tank took two days. Despite the fact that the technical task of designing a simplified hull and turret was issued on July 23rd, work on the 060 started on July 20th.

Astrov's construction bureau set a world record on the speed of developing the tank: last blueprints were completed on July 28th. The entire documentation cycle took a week. This is confirmed by dates on the blueprints.

The layout of the 060 is interesting enough to be given some details. It largely copied the T-40, but with several changes that had to do with a not so pleasant story, namely with the engine. In October of 1940, the People's Commissariat of Aviation Manufacturing took away GAZ's GAZ-11 and GAZ-202 engine manufacturing plant, in order to produce M-105 aircraft engines. GAZ was forced to put on pause a number of vehicles that used the GAZ-11 engine, including the T-40 tank. In the end of 1940, the idea of using a ZiS-16 engine (ZiS-5 forced to 85 hp) and its diesel version, the D-7. One tank was sent to ZiS, but resulted in an unsatisfactory outcome. The new engine was too large. By June of 1941, issues with the GAZ-202 engine were resolved, but it seems that the head of the hull group, A.B. Bogachev, resolved the crisis, despite the hull being 15 cm shorter, the tank fit not only the stock GAZ-202 engine, but, with some modifications, the ZiS-5 engine.

The story of 030's and 060's armament is also interesting. The initial plans called for the same armament as the T-40: a DShK with a coaxial DT. Plans had to be changed, since the DShK's manufacturers (mostly the factory #507 in Lopasnya) could only produce several hundred of these guns per month. On July 23rd, 1941, the deputy People's Commissar of Defense G.I. Kulik assembled a meeting on the armament of the T-60. A replacement was needed for the DShK, and it was quickly found.

In 1936, an automatic 20 mm cannon was developed by the OKB-15: ShVAK (Shpitalniy-Vladimirov, aviational, large caliber), which was the first mass produced example of this weapon type in the USSR. The gun was unified with the large caliber machine gun of the same name. By the start of the Great Patriotic War, the gun was widely used on fighters and ground attack aircraft. Its ball turret version could easily be mounted on a tank.

On July 26th, GKO order #289ss "On the armament of the T-60 tank" was issued. According to the order, it was to be armed with OKB-15's ShVAK 20 mm autocannon. In September, it received the index of TNSh/ShVAK model 1941.

When order #289ss was issued, a tank version of the ShVAK did not yet exist. The first prototype was installed in the T-40 (serial number 11726), and was tested between August 7th and 10th of 1941. Elements of the wing and turret versions of the gun were used, which allowed to mount the gun without developing radically new components. The gun sight remained the same: TMFN (telescopic, Maron-Finkelstein, machine gun). The only difference was a new scale on the sight.

On July 30th, before the gun was even tested, GAU was ordered to produce a number of ShVAKs, optics, and 15 millon shells. On August 3rd, the order was increased to 15 million for factory testing and 35 million for the army. The real picture was far less optimistic: on September 17th, GAU reported that it could only manufacture 30 000 shells that month. On the next day, after personal attention from the deputy chief of the council of the People's Commissars, L.Z. Mehlis, the People's Commisar of Ammunition P.N. Goremykin extended the promise to 30 000 shells for HTZ, 20 000 for GAZ, and 50 000 for #37. 3.5 million shells were to be produced in October. The order for factory #37 was mostly theoretical: T-30s were armed with DShK machine guns until the beginning of October.

According to plans, factory #37 was to produce 030s from August 1st, and HTZ and GAZ were to produce 060s from August 15th. Factually, the only hull assembled on time by the Ordzhonikidze factory in Podolsk was a 060 prototype hull made from mild steel. By the middle of August, Lening factory #69 (Krasnogorsk) produced only 25 TMFP sights, and Kirkizh factory #2 (Kovrov) produced only 15 TNSh. Factory #37 began building an experimental 060 on August 17th. The turret used was a T-40 one, with a DShK (in theory, the machine gun was never installed). This tank was assembled to familiarize GAZ with production of the 060. Astrov and Okunev personally drove it to Gorkiy, after which they returned to factory #37.

GAZ was a reasonable choice for the T-60. The Molotov Gorkiy Automotive Factory was one of factory #37's main partners for the T-40 tank. The Kharkov factory that was meant to be the main manufacturer of the T-60 was a whole different story. At the start of June of 1941, the construction bureau of the Scientific Auto-Tractor Institute (NATI, today NAMI) developed an armoured tractor in partnership with HTZ. The vehicle was indexed HTZ-16, based on the heavily modified chassis of the SHTZ-NATI tracked tractor. On July 20th, 1941, before the construction of a prototype, GKO order #219ss ordered 2000 armoured tractors from HTZ. GABTU understood that the HTZ-16 was a temporary measure, and could not be a fully fledged fighting vehicle. On the same day, they assigned HTZ to produce the T-60.

The time spans and volumes in order #222ss were unrealistic. Technical documents were to be sent by the construction bureau of factory #37 on July 27th. The first blueprints made it to HTZ on July 28th, but most of the documentation arrived only on August 10th. By August 16th, the QA standards still have not arrived to HTZ, nor did the list of components for spare parts and toolboxes.

Aside from a lack of hulls, HTZ had another problem. The T-60 was a "foreign" project, and the workers were not very enthusiastic about producing a small tank. By the middle of August, only 6 people were assigned to the T-60 project. This was explained by a lack of staff. A number of blueprints received from #37 were reworked to suit HTZ's needs, which also took time. A series of components, including the optics and tool attachments, were reworked to be compatible with the HTZ-16. In short, HTZ and its suppliers gave minimum priority to the T-60 project.

HTZ's management tried as they could to keep HTZ-16 in production. Its removal necessitated interference from the top. The ferocity of this fight can be seen in the report of military engineer 3rd class Kulikov, senior engineer of the 3rd department of BTU KA, compiled in the first half of September of 1941.

"The parallel production of HTZ-16 and T-60 is planned until the second half of September (17.9.41). The production of the HTZ-16 chassis is done using the tractor conveyor in the main plant, while production of the T-60 is planned for the middle of nowhere, on a temporary conveyor. Until Malyshev arrived, the workers were of the opinion that "maybe the T-60 will be cancelled". After he chased them around for a bit, there were changes. The plants paid devoted more attention to the T-60. Until then, the tank was classified, so none of the workers knew what the factory would produce."

On September 13th, 1941, almost a month after the planned production date, the first T-60 was assembled at HTZ, using a hull and turret produced at the Voroshilov factory. At the time, there were 12 sets of hulls and turrets, from 3 different suppliers. In September, only 7 tanks were assembled and sent out, which equaled the amount of available engines.

On September 20th, the Germans approached Kharkov, and establishments in the city began evacuation. HTZ began preparing on September 17th. The factory was to be evacuated to Stalingrad. They did not have time to evacuate completely. Germans storming the city captured equipment and several T-60 hulls.

For the next few months, GAZ remained the only factory capable of producing T-60s.

Original article available here

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