Tuesday 31 December 2013

HPZ BT-7 and T-35 Woes

"Report on the condition of tank-building at the Kharkov Locomotive Plant in the first half of 1936

The "Spetsmashtrest" plan assigned the production of 510 vehicles to HPZ in the first half of 1936.

Only 425 tanks were produced in this time. ABTU accepted only 271 of these tanks. More specifically: out of the 100 tanks prepared in January, ABTU accepted 60, from 115 in February, ABTU accepted 99, out of 95 from March, 81, out of 51 in April, 25, out of 48 in May, none, out of 16 in June, 6.

The main problem is the low quality of a number of components in BT-7 tanks, reducing their combat quality. This is mainly caused by the design of the BT-7 using several components from the BT-5, which the factory transferred without consideration for the increased engine power and vehicle weight.

Data in our possession indicates that the chief of the tank design bureau at HPZ, engineer Firsov, removed himself from regulating work on this tank. All of Firsov's work was transferred to his assistant, Granberg, who had no experience in tank building, and did not make correct technical decisions in the design and construction of the BT-7.

The following defects of BT-7 tanks have been established:
  • Incorrect assembly of the gearbox, resulting in mass breakage of the gears.
  • The dust filter is inadequate. After 30-40 hours, the engine ceases working, due to dust in the cylinders and cylinder rings.
  • Installing and removing the batteries is difficult. Instead of the required 8 minutes, it takes up to 2 hours.
  • The removal of water from the radiators is inconvenient, plus it is impossible to purge all oil from the oil system.
  • There are many cases of shorts in the electrical systems, increasing the chance of fire in the tank.
  • Tracks are useful for 700-800 kilometers. According to the warranty negotiated with the RKKA, they should be functional for 2000 kilometers.
  • Additionally, after 100 km, the track is loose and hangs on the wheels, slides off, and does not allow the tank to move normally.
  • After ballistics tests of a 1935 hull and turret, it was deemed that the rivets are not bulletproof. A part of them was knocked out, the gas tank was penetrated, as were the hinges on the driver's hatch.
  • Only one defect from other factories is worthy of attention: the use of ball bearings #6217 and #6411 from the 2nd State Ball Bearing Factory in gearboxes and gear change brackets. These ball bearings, due to metal quality and poor thermal conditioning, cannot be used on tanks. All ball bearings on tanks at HPZ were replaced, but the tanks in the army still contain 2nd GPZ ball bearings.
In March of this year, when the first problems with gear change brackets happened, the tank laboratory chief  Gorbodei at HPZ ordered that the gear change bracket should be hidden, and not disassembled or analyzed. Gorbodei claimed it was the order of the deputy chief of the tank department, engineer Kulikov, and said that if the bracket is disassembled, the military representatives will know, and will cease accepting tanks.

HPZ continues to ignore our questions regarding the quality of BT-7 tanks, as mentioned in our previous report from April 19th of this year (#528).

The factory director, comrade Bondarenko, was called to Moscow in June of this year. According to NKVD information, despite these defects, another batch of BT-7s is going to be sent to the RKKA. 

As for the T-35 tanks, the factory was supposed to produce 9 in the first half of this year, and only produced 6.

The existing T-35 tanks have the following problems:
  • Rapid wearing of the engine components due to a poor dust filter.
  • The rollers on the gearbox bend and vibrate during operation.
  • The final drives leak. It is necessary to redesign the final drives.
HPZ is currently working on correcting these faults with T-35 tanks.

Acting Deputy People's Commissar of Internal Affairs of the Ukrainian SSR
Commissar of State Security, 3rd grade, S. Mazo

July 16th, 1936
RGASPI 558-2-142

You know you screwed up when the NKVD comes knocking at your door. Contrary to popular history, all of HPZ didn't immediately face execution, and action was taken to resolve the identified problems. 

"To the People's Commissar of Heavy Manufacturing, comrade G.K. Ordzhonikidze

The acceptance of BT-7 tanks with the M-17 aircraft engine and reinforced gearbox continues on July 15th, after lengthy trials with ABTU and the People's Commissariat of Defense. 

The missing BT-7 tanks in the first half of 1936 will be delivered to the NKO by November 1st.

As for the issues communicated by comrades Gai and Mazo, we consider it necessary to report the following:

On the BT-7 tank
Gearbox: in April of 1936, it was determined that the conical gears of the gearbox are destroyed before the warranty period expires when operating on tracks. When this was discovered, HPZ immediately stopped sending tanks, and tested 13 tanks on tracks. 7 tanks did not manage the warranty period, only making it 500-700 km on tracks. These trials demonstrated that the cause of these breakdowns is the increased momentum of the M-17 engine when compared to the Liberty engine.

HPZ used all possible resources to make 9 design changes to the gearbox, increasing its strength 2-2.5 times compared to the May production gearbox.

At the same time, in order to increase the warranty period, according to the professor of the Academy of Motorization comrade Stepanov, the factory decreased the momentum of the M-17 engine from 280 kg-m to 220 kg-m.

Four BT-7 tanks with reinforced gearboxes and 220 kg-m moments were tested at great length by the factory and ABTU. Trials were performed in most difficult conditions for the gearbox, exclusively on tracks (the wheel load on the gearbox is 2-3 times lighter). Even in these conditions, the two first tanks travelled 1400 km, and the second two, 2000-2500 km. These trials convinced ABTU of the combat ability of the fast convertible drive BT-7 tank with the reinforced gearbox, which is capable of providing 2000 km of service, of those 1300 on tracks, which is acceptable by standards set by ABTU for 1936.

As for the history of the BT-7's development, we report that as of January 15th, 1935, the factory and ABTU completed an experimental BT-7 tank, that had an identical gearbox to the BT-5. That tank travelled 1100 km on tracks and 1300 km on wheels. A second identical prototype was tested by ABTU on an obstacle course.

On January 29th, 1935, the factory presented ABTU with a design for a BT-5 gearbox (#08-S20) and changes to it (#08-S23). The chief of ABTU's technical department, brigade engineer comrade Lebedev, wrote on the blueprint on January 29th, 1935:
  1. The conical pair component must be altered according to blueprint #08-S23.
  2. Produce an experimental prototype of a further reinforced version of this component, according to diagram #P-11-1"
Blueprint #08-S23 contained a number of changes to the BT-5 gearbox, consisting of:
  1. An increased number of retention bolts, from 10 to 12, with an increased diameter of their location (110 mm to 135 mm).
  2. The roller clamps are reinforced, 17 mm from 13 mm.
  3. The gear clamps are reinforced, from 13 mm to 11 mm.
On February 5th, 1935 (after 8 days), Lebedev was presented with blueprint #08-S23, which he accepted.

On June 19th, 1935, as a result of an NKO report, the STO accepted this tank into service.

The subsequent series of events, as detailed above, shows that the factory and ABTU made a miscalculation in the attachment of the gearbox conical pair, which has since been corrected.

Simultaneously with the new production of the BT-7 with a new gearbox, 687 BT-7 tanks already in the army will also receive new gearboxes. According to the agreement with ABTU, the gearboxes will be replaced between August 1st and December 10th, 1936.

ABTU is counting the unreinforced BT-7 gearboxes removed from its tanks towards the BT-5 spare parts contract for 1936.

Anticipating the growing requirements of ABTU, HPZ began development of even more reinforced gearboxes, which will begin testing in the 4th quarter.

ABTU released special instructions on March 4th, 1936 on how to drive the BT-7 tank. These instructions should be read by anyone driving a tank, not just the BT-7.

On the issue of wheel bolts: the issue was resolved by replacing regular metal bolts with bolts made from #5 steel.

On the issue of tracks: as on all tanks, BT-7 tracks break in during the first 100-200 km, and somewhat lengthen, requiring adjustment. An idler adjustment mechanism exists on the tank for this purpose. Latest factory and army trials show that, if track pins are replaced, tracks last from 1161 km to 1564 km.

On dust filters: currently, new dust filters are being used, several times better than the old ones. After 2500 km of trials with the new filters, no engine trouble is seen. These new filters are installed in all vehicles produced by the factory.

On removing batteries: the batteries must be removed very rarely, in exceptional conditions. Due to the increased size of the ammunition rack on the BT-7 and larger size of the M-17 engine, the removal of batteries is harder than on the BT-5. Currently, openings are cut in necessary plates to reduce the time of removal to 30-40 minutes, same as on the BT-5.

On the flushing of water and oil: it takes 9 minutes and 30 seconds to flush water from the BT-5 radiator. It takes 4 minutes and 30 seconds to do it on the BT-7. Performance was not reduced. As for flushing oil, an additional hatch is present on the BT-7 which enables flushing all oil. Currently, instead of iron pipes, red copper pipes are used, which increases the speed of flushing oil.

On shorts in the electrical system: we do not know of any shorts in the electrical system. 

On the bolts and rivets: factory trials of various hardened steels revealed that the best bolts and rivets are made from nickel-chrome steel. The terms for producing nickel-chrome steel bolts are currently being negotiated with ABTU chief comrade Bokis.

On the 6247 and 6411 ball bearings: in some cases, 6247 and 6411 ball bearings produced by the 2nd GPZ did break earlier than imported ones. ABTU requested that all new vehicles should use imported ball bearings. Currently, 6411 ball bearings are imported, and 6217 ball bearings are replaced with 42217 ball bearings from 1st GPZ. These ball bearings show satisfactory quality in trials.

On the T-35 tank:

As a result of 1000 km of trials with a new dust filter, no engine components were worn out. Current production T-35s carry the new air filter.

The same trials revealed no defects in the gearbox. The gearbox works reliably.

The final drices leak when lubricant levels are higher than the grease retainer cork. Currently, a higher density grease retainer is in development. As for a redesign of the final drive, the final drive works reliably, and there is no need for that.

Spetsmashtrest chief Neiman
Factory director Bondarenko

July 25th, 1936"
RGASPI 558-2-142

Sunday 29 December 2013


As any factory, Soviet tank factories took quality seriously. Every tank would be tested, and the equipment on it recorded. Here is one such document for a KV-1 at the Kirov factory.

"Act #26

On January 26, 1941, we the undersigned, representatives of the Kirov factory, 1st department chief comrade A.I. Lantsberg, assistant OTK chief comrade N.V. Sokolov, SD-2 deputy chief comrade N.A. Zhukov, SD-2 OTK chief comrade L.A. Sadovskiy, referred to as "factory", on one side, and the GABTU KA military representative, Military Engineer 2nd grade comrade M.F. Bubyakin, referred to as "GABTU KA representative", on the other side, based on the agreement with the Kirov factory #.......... from January "  " 1941, compose this act of the following:

The factory completed, according to blueprints and technical specifications, confirmed by GABTU KA, a "KV" type tank #M-9685.

The factory QC department tried and tested all components and mechanisms during the process of their production, assembly, and installation, tested the tank over 390 kilometers, and deemed it acceptable and compliant with technical requirements.

The AU KA military representative performed an inspection, and tested the F-32 gun installed on the tank, and deemed the gun and its sights acceptable.

The US KA military representative performed an inspection, and tested the 71-TK-3 radio, and  TPU-3M internal communication device, and deemed them acceptable. The GABTU KA military representative performed technical testing of KV #M-9685 over 108.5 km, checked is completeness, and, having deemed it worthy, accepted it and sealed it with the Military Representative seal.

KV tank #M-9685 is equipped with an F-32 gun: gun body #62, recoil brake #47, return gear #49, TOD-6 #0635, PTK #11013, PT-6 #0737, DT machineguns #UTs204, UTs330, UTs300, USh328. The KV tank #M-9685 is equipped with a 71-TK-3 radio station, transmitter #784, receiver #782, TPU-3M #84. The tank uses the V-2-K engine #1510-03, gearbox #B-14.

The tank is equipped with a set of spare pars according to contract #....... The GABTU KA military representative issued certificate #047[illegible] on January 28th, 1941, on accepting this KV tank into service with the Red Army.

1st Department Chief, Lantsberg
SD-2 Deputy Chief Zhukov
SD-2 OTK Chief Sadovskiy
GABTU KA Military Representative Bubyakin
OTK Chief assistant Sokolov

GABTU Military Representative seal."
CAMD RF 38-11355-326

Here is a similar document for a T-50 tank.

"Act #19

July 31st, 1941. The undersigned, Production Chief comrade Shlaugman, OTK chief comrade Gudkov, assembly plant chief comrade Gushman, OTK chief of the assembly plant, comrade Grigoryev, referred to as "factory", on one side, and the Red Army GABTU military representative, Military Engineer 2nd Grade comrade Kishtalov, referred to as "GABTU military representative" on the other side, based on agreement #B-1-41 from April 30th, 1941, compose this act of the following:

The factory completed, according to blueprints and technical requirements established by GABTU, a T-50 type tank #...........

The factory QC department tried and tested all components and mechanisms in the process of their production, assembly, and installation, tested the tank over .... kilometers, and deemed it acceptable and in compliance with technical requirements within tolerances established by factory #174 on July 10th of this year.

The GAU KA military representative performed an inspection of the artillery system installed on the tank, and deemed it and its sights acceptable.

The GABTU KA military representative performed an inspection of the #........... T-50 tank and tested it over ..... kilometers, found it acceptable, and sealed it with the Military Representative seal.

T-50 tank #K-11232 is equipped with a 45 mm gun #V-7763, mount #......., PPSh #..... TOS #12018, PT-1 #15114, DT #PB-420 and NB-484.

T-50 tank #K-11232 is equipped with an R-10 radio #.......

The tank has a V-4 engine #140400 and gearbox #17409.

The tank is equipped with a set of spare parts and instruments, according to the agreement.

The GABTU KA military representative issued certificate #..... on "   " ...... 1941 on the acceptance of the T-50 tank into the Red Army.

Production Chief
OTK Chief
Assembly Plant Chief
Assembly Plant OTK Chief
Military representative"
CAMD RF 38-11355-237

Seems that the document was completed in a hurry, a number of fields were left blank, such as some instances of the tank number. That doesn't mean that this tank was not accepted. It was shipped to the 150th Tank Brigade, and currently resides in the Kubinka tank museum, with a dent in the left side of the turret as a memory of its combat service.

QC wasn't only performed on domestic vehicles, but on captured ones as well.

"Technical inspection act

On August 29th, 1945, a commission consisting of [illegible] on the basis of orders from the deputy proving grounds chief, inspected a JagdTiger B vehicle #305083 for the purpose of establishing the technical condition of the vehicle.

After inspecting the vehicle's documents, the commission established that:
  1. The vehicle travelled for ___ hours and 250 kilometers. The vehicle last underwent (medium/complete) repairs ___ hours and ___ kilometers ago.
  2. Vehicle inspections and engine start revealed that:
    1. The vehicle is functional. The engine works normally. 
    2. The gun is capable of firing, but the barrel is covered in rust.
  3. Trials revealed that all components of the vehicle are functional. The inspection was carried out over 2 hours and 50 minutes and 8 kilometers. In total, the vehicle travelled 258 km. 
  4. The commission concludes that this vehicle is acceptable for use.
Commission Chief.
Commission Members."
CAMD RF 38-11355-2725

A handwritten note on the page instructs 300 km of trials to be carried out. 

This Jadgtiger can be seen in the Kubinka tank museum.

Yale University Press Blocks Access to "Documents of the Soviet Era"

The Russian "Documents of the Soviet Era" website (sovdoc.rusarchives.ru) contained many scans of documents from RGASPI, including a great number of tank-related documents. I have translated a number of these documents on this blog. Upon attempting to access the latest batch, I was faced with a message in broken English, warning me that Yale University Press prohibits access to documents on this website. I was given the "option" to use Yale's website, which somehow manages to be much worse than the relatively primitive but robust RGASPI one, with two critical problems. One is that I can't search in Russian. That wouldn't be that bad, it would still be possible to get the document number from RGASPI and browse manually, but then the second problem comes into play. The RGASPI website was free to everyone. The Yale website doesn't show you the document unless you are a part of an academic institution that pays them money.

Looks like a major archive source is now closed to me (and, therefore, the English speaking public) because some guy somewhere wanted to make more money.

World of Tanks History Section: T-100 Variants

In 1938-1939, Soviet engineers worked on a new heavy tank with anti-shell armour. The vehicle was going to replace the menacing looking, but not all that dangerous, T-35. Three projects competed, and the KV won. The T-100 and SMK remained prototypes, albeit ones in metal.

The T-100 was built at factory #185 in Leningrad. It was a 58 ton vehicle with two guns: 76 and 45 mm. In December of 1939, the Military Council of the North-West Front ordered an engineering vehicle to be built on its chassis. The factory began working on this project, but soon after, ABTU demanded that an assault tank be built on the T-100 chassis, with a 152 mm gun, designed to combat enemy fortifications. Work on the engineering tank ceased. Factory director N. Barykov obtained permission to use the 130 mm B-13 naval gun instead of a 152 mm gun.

The new vehicle received the index T-100-X. Instead of a rotating turret like on the T-100, the T-100-X had an immobile wedge-shaped casemate. The hull was to be built at the Izhor factory, and the suspension at factory #185.

In order to speed up construction, the casemate was simplified. This was the shape that it took in March of 1940. Along with a new casemate, the vehicle received a new name: T-100-Y. This SPG is also known as SU-100-Y. The original intention was that the SPG would be trialled in combat against the Finns, but the war already ended. Nevertheless, the vehicle was sent to Karelia to shoot at bunkers. The gun performed well, but the military did not like the large size and heavy weight of the SPG, and so it remained a prototype. Sources say that it fought with the experimental SU-14 and SU-14-1 SPGs in defense of Moscow in winter of 1941, providing indirect fire support against the Germans.

In January of 1940, another project on the T-100 chassis started. Army Commander 1st grade G. Kulik ordered the tank to be equipped with a 152 mm M-10 howitzer in a rotating turret. This project was indexed T-100-Z. The turret was ready by March of 1940, but it was never installed on the T-100. That project ended when the KV-1 and KV-2 were accepted for service.

Original article available here.

Saturday 28 December 2013

Planetary Mechanism

"To the chief of the 3rd department of GABTU
December 24th, 1940

One of the most important tasks of our scientific and engineering minds in the area of tank development is the task of making driving a tank easier, and making it more manevuerable.

Planetary mechanisms make great progress in this direction, especially on medium and heavy vehicles.

Dean of the Faculty of Armoured Warfare, associate professor, comrade Zaichik proposed a new planetary type mechanism that eases turning, increases maneuverability, and reduces fuel consumption.

Transmission controls that ease the driver's job have also been developed.

The suggestions have been approved by the Tracked Vehicles department head of the Armoured Warfare faculty, professor Christie.

Due to the relevance of the task of developing a planetary transmission for our medium and heavy tanks, we wrote to the NKV Technical Council to ask to include a section titled "Planetary transmissions with special turning mechanisms" in the plan for 1941, and issue funds to implement it.

We ask you to contact the Technical Council in order to confirm the need for this topic and development of requirements for this project.

Institute director, doctor of technical sciences, N.G. Bruevich
Faculty dean, assistant professor, candidate of technical sciences, Zaichik"

The mechanism was meant for the KV-3, but due to its cancellation, only made it into the Object 701.

And no, the USSR didn't invite Walther Christie to teach, this is Mihail Konstantinovich Christie, no relation.

Friday 27 December 2013

World of Tanks History Section: Jagdtiger

The end of WWII was a difficult time for Germany's tank manufacturing. The Reich experienced a lack of natural resources that were necessary for production. Even in conditions when reasonable engineering solutions were not possible, the country was obsessed with wonder-weapons that would turn the course of the war and stave off inevitable defeat.

In this wild goose chase, the Germans created vehicles ranging from interesting to those of questionable value. The Jagdtiger heavy tank destroyer lies somewhere in between.

A large part of the blame for wasting resources on questionable vehicles lay on Hitler. He was very fond of massive armoured beasts. The Fuhrer did not have a technical education, and did not understand that a vehicle's fighting ability is not determined by its mass and size.

Hitler signed the order to create a heavy anti-tank SPG in the fall of 1942, shortly after work began on the heavy Tiger II tank. The first two experimental vehicles, built on the VK 30.01 (H) chassis were sent to fight at Stalingrad, but, after German defeat, both were lost. For a short time, work on a heavy tank destroyer ceased. The Germans were confident in victory, and did not consider it necessary to create special vehicles. Existing ones were enough.

In 1943, Henschel and Krupp jointly began construction of a tank destroyer. On October 20th, 1943, a wooden model was shown to Hitler. He was ecstatic; and ordered the production of this vehicle started next year. In April of 1944, Hitler named it: Jagdpanzer VI Tiger Ausf. B Jagdtiger, later shortened to "Jagdtiger".

Production was planned for Henschel and Nibelungenwerke factories. But first, the vehicle's cost should be reduced to a reasonable level. The Fuhrer's favourite, Dr. Porsche, tried to leave his mark here. His construction bureau suggested that the most complicated part of the vehicle, the suspension, should be the same as the one on the Ferdinand. Porsche's suspension had external torsion bars. This made it simpler and cheaper. The mass also decreased by 2.5 tons. Two vehicles were built with this suspension, one of which made it to trials before Henschel's analogue did. However, a bogey broke down during testing, which was immediately taken advantage of by Porsche's opponents from the Armament Directorate. Henschel's vehicle was recommended for mass production. In July of 1944, Jagdtigers began construction in Sankt Valentin. Until the middle of October, the Germans managed to produce 50 vehicles. On October 16th, Allied aviation delivered a 140 ton strike to the factory. The destruction was so great that production ceased until Spring of 1945. In total, the Germans built between 70 and 79 vehicles, according to various sources.

Only two units were armed with Jagdtigers. These were the 512th and 653rd heavy tank destroyer battalions. Famous German tank ace Otto Carius commanded the second company of the 512th battalion. In March of 1945, these tanks first took part in combat operations. The first company, consisting of 6 TDs, defended the bridge across the Rhein near the city of Remagen. Without the loss of a single vehicle, the Germans deflected the Allied attack and destroyed several tanks. The battles at Remagen demonstrated the power of the 128 mm gun, penetrating any enemy tank at a distance of up to 2.5 km.

Carius' company fared significantly worse. The problems weren't due to Allied forces, they were due to the SPG crews themselves, picked from newbies with poor training and even worse morale. During the defense of Siegen, two vehicles left the field of battle when no danger was present. The inexperienced driver pushed the TD so hard that it irreparably broke down. When the commander understood that it could not be moved again, he ordered the crew to evacuate and destroyed the vehicle.

Three more of second company's Jagdtigers were destroyed by aviation en route to the city of Siegburg. The rest of the vehicles took part in a battle for the Ruhr pocket. Over 5 days, the Jagdtigers of the 512th battalion destroyed 40 American tanks. When the position of the unit became hopeless, the remains of it surrendered.

Nine vehicles fought in Austria until May 9th, 1945. In the evening, the three that were still in service made a dash westward, to surrender to the Allies instead of the Red Army. Only two vehicles broke through, one was knocked out and destroyed by its crew. The Soviet losses in that battle consisted of two IS-2 tanks and two KV-85 tanks.

The 653rd battalion started fighting sooner, in December of 1944, as a part of the 5th tank army. There were few Jagdtigers in the unit, but they made significant breaches in the tanks of American tanks. On December 7th, 1944, one such vehicle destroyed 19 Shermans over 3 hours. In return, it was only hit three times, none of which penetrated the armour.

On May 6th, 1945, Soviet forces managed to knock out one of the 653rd's 6 Jagdtigers that were trying to break through to American lines. The crew could not blow it up under Soviet fire. The vehicle was captured, and is now held in Kubinka. The other 5 were destroyed by the Germans at the Austrian border.

Despite being the most powerful tank destroyer of the war, the Jagdtiger did not manage to have any effect on its outcome. Firstly, they were too few in numbers. Secondly, their construction could not boast high reliability. The Germans themselves knew it, and equipped each one with two self-destruct charges. One was placed right next to the breech of the gun. One can only imagine how the crew felt, sitting next to such a deadly cargo. In his memoirs, Otto Carius writes that the Jagdtiger's 8 meter long barrel loosened after even a short off-road drive. Subsequent accurate fire was impossible. Carius also writes about an unfortunate design of the gun stopper, with which the gun was fixed in place during travel. It was impossible to take it off from inside the TD. Therefore, one crewman had to risk his life getting out from behind its armour after the Jagdtiger has made contact with the enemy. Many harsh words were aimed at the suspension, which was heavily overloaded, and was prone to frequent breakdowns.

The Jagdtiger was the heaviest mass produced vehicle of WWII. For 1944-1945 Germany, it was unaffordably expensive, and its many drawbacks nullified its worth as a combat unit. Perhaps it would be more useful had it appeared in the German army earlier, but from history that we know today, it was a hopeless project.

Original article available here.

Wednesday 25 December 2013

Ferdinand Losses

The Battle of Kursk is, perhaps, the most famous tank battle in history. In that battle, the Ferdinand assault gun was introduced, seemingly invincible, with the most powerful tank gun fielded by the Wehrmacht to date. Due to the relatively few numbers of Ferdinands manufactured, it is possible to account for nearly all of them.

Ferdinands from s.PJA. 654 were sent to the railroad station of Ponyri, and many of them met their end there. Tank.UW.ru has a list of the damaged tanks, and Photo-war has pictures of some of them.

Here is the translated list:
  • I-02 hit a mine, lost its left track and a road wheel, and caught fire. The vehicle burned up.
  • II-01 was hit by an incendiary bottle and burned up.
  • II-02 hit a mine, lost its right track and road wheels. It was later hit by an incendiary bottle, and burned up.
  • II-03 was hit by a shell, and subsequently an incendiary bottle. The vehicle burned up. Edward Yermolayev helpfully identified it as a Ferdinand that appeared in other articles.
  • #501 hit a mine and lost a track. It was repaired and tested at NIBT.
  • #502 lost an idler from explosives. This vehicle was subsequently used for penetration testing. 
  • #514 hit a mine, lost its track and suffered a damaged road wheel. The vehicle burned up.
  • #522 was destroyed by explosives, track and road wheels destroyed. The fuel ignited. The vehicle burned up.
  • #523 was destroyed by explosives, lost a track, and some road wheels. The vehicle was burned by its crew.
  • #524 hit a mine, lost a track, and was set on fire.
  • #601 lost its right track from a shell hit. The vehicle was ignited externally and burned up.
  • #602 was penetrated by a 76 mm shell in the left side. The gas tank ignited and the vehicle burned up.
  • #734 was destroyed by explosives, lost a track. The fuel ignited, the vehicle burned up.
  • #712 was hit by a shell, and its right leading wheel was destroyed. The crew bailed out. 
  • #713 lost both idlers from shells and caught fire. The vehicle burned up.
  • #723 took shots to the suspension and gun mantlet, the gun was jammed, and track destroyed.
  • #732 was hit by a shell, and had its third bogey destroyed. The vehicle was set on fire.
  • 150061 lost its idler and gun to artillery fire. The crew was captured.
  • 150090 hit a mine, track destroyed. Vehicle was repaired and sent to Moscow to an exhibition of captured vehicles.
  • An unknown Ferdinand was destroyed completely by a direct hit from a Petlyakov bomber.
This site also has photos of the Ferdinands that met their end in the North half of Kursk. Here are the translations, with the exception of exact matches with vehicles above:
  • #111 caught fire due to an overheated engine while climbing a hill.
  • #112 caught fire for an unknown reason, perhaps due to a faulty fuel system.
  • #113 hit a mine.
  • #122 was lost at Ponyri (very likely that it is serial number 150090).
  • #132: unknown, no photos of this Ferdinand destroyed.
  • #134 was mistaken for an enemy tank, had its track damaged by German artillery, and was abandoned.
  • #232: unknown, no photos of this Ferdinand destroyed.
  • #311 was, most likely, disassembled for parts.
  • #323 likely hit a mine and was immobilized, destroyed by crew.
  • #331 was stuck in soft ground. A Soviet infantry attack prevented the crew from destroying it.
  • #333 was captured at Podmaslovka.
  • #IN1: unknown, no photos of this Ferdinand.
  • #IN2 was destroyed at Ponyri. Photograph shows two road wheels on the left side destroyed.
  • #II-03 and #732 were destroyed right next to each other at Ponyri, facing away at a 90 degree angle.
  • #531 was destroyed, towed, and used for spare parts.
  • #602 was lost at Ponyri. Cause is unknown, no photos exist.
  • #614: unknown, no photos of this Ferdinand destroyed.
  • #623 was lost while trying to tow #634. A shell went through the open driver's hatch and hit the driver.
  • #624 got stuck on soft ground and was captured.
  • #634 sank into the ground. In an attempt by two other Ferdinands to pull it out, #623 was lost.
  • #654 was lost at Ponyri. Cause is unknown, no photos exist.
  • #711: unknown. There is no caption, and photographs do not show any obvious damage.
  • #731 was destroyed by heavy howitzer fire.
  • #733 was captured at a repair facility.
  • #734 was lost at Ponyri. Cause is unknown, no photos exist.
There is also a list of Ferdinands that are either not identified or might be an already mentioned Ferdinand.
  • A vehicle from s.PJA.653. Broken down, the Germans attempted to tow it, but failed. Potentially #111.
  • A vehicle from s.PJA.653 was captured at the Orel railroad station.
  • Unknown vehicle, likely from s.PJA.653, was destroyed next to #731. There exists a theory that it is #614.
Ferdinands weren't only deployed at Kursk. Some were deployed, and lost, in Italy.
  • #101: unknown.
  • #102 had an engine fire, and was abandoned by its crew. 
  • #111 was destroyed by a mine, and towed away.
  • #112 was destroyed by its own crew due to mechanical problems.
  • #113 had its tracks damaged by artillery, and abandoned by its crew. The loader was killed.
  • #114 got stuck on soft ground and destroyed by its crew.
  • #121 went over a bridge, which collapsed. The tank was destroyed by its crew.
  • #122 caught fire after being strafed by American ground attack planes.
  • #123 was destroyed by American ground attack planes.
  • #124 was abandoned due to mechanical problems.
  • #131 got stuck on soft ground and destroyed by its crew.
That's a total of 54-57 Ferdinands accounted for, out of 91 built. As you can see, quite a number of them were taken out by infantry or explosives, instead of other tanks, serving as an example that tanks do not exist in a vacuum with other tanks, and any tank needs good infantry cover. A number of the tanks suffered mechanical failure or were lost after getting stuck, showing that armour and armament, while important, are no good to you if your tank is its own worst enemy. 

Tuesday 24 December 2013

Anti-Ferdinand Guide

I have previously written about brochures describing how to take out German tanks, and posted excerpts from them. I have since found a full version of one of them, the one describing how to take out a Ferdinand. You can find it here.

"Weak points of the German Ferdinand SPG and methods of combat with it" is a mouthful of a title, but very descriptive. The upper right corner helpfully reminds you: "Death to the German occupants!". The lower part of the page holds the publisher information: military publishers of the People's Commissariat of Defense, Moscow, 1943. 

The booklet doesn't waste time on introductions, and gets straight to the point.

"Weak points and methods of combat with the Ferdinand SPG

1. Suspension

The suspension puts the SPG in motion. The most vulnerable parts of the suspension are the rear most-wheel (idler), front-most wheel (drive wheel), and road wheels. 
Artilleryman! Open fire at the suspension with AP and HE shells of all calibers from all distances. The SPG will stop.
Blow up the bottom of the hull and suspension with mines.
Sapper-miner! Quickly set up mines on likely directions that the SPG will move in. Keep an eye on the SPG's movements. Prepare surprises for the Ferdinand.

2. Lower vertical plate

Components of the SPG are located past the lower vertical plate. 
Open fire with: APCR from 45 mm guns at 500 meters.
AP or APCR from larger caliber guns at 500-1000 meters.

3. Turret armour plates

The crew is present in the turret, as well as the gun mechanisms and ammunition.
Open fire: from a 57 mm gun with AP shells at 1000 meters.
From 76 mm model 02/30, 39, and 42, with APCR shells at 300-500 meters.
From 76 mm and 85 mm AA guns: with AP from 300 and 1000 meters.

4. Upper vertical hull plate and rear armour

The ammunition is stored behind the vertical part of the rear armour, and gas tanks and engine are located behind the front part. The lower sloped plate covers the electric motors. The exhaust system is behind a hatch in the center. The upper sloped plate has an emergency hatch.
Open fire from a 57 mm gun at 1000 meters.
From 76 mm model 02/30, 39, and 42, with APCR shells at 300-500 meters.
From 76 mm and 85 mm AA guns: with AP from 300 and 1000 meters.

5. Driver, radio man, and engine hatches

One of the weak parts of the SPG is the hatch on top of the gas tank.
Open fire at the lower part of the upper front plate with HE shells of all calibers.
Hit the hatches with AT grenades. Hit the air intakes with incendiary fluid.

6. Bottom of the hull

When the SPG climbs a hill, it exposes the bottom of the hull.
Open fire with any caliber gun at any distance.

Brief data on the Ferdinand SPG

Length: 7 m
Width: 3.5 m
Height: 3 m
Mass: about 70 t

Armour thickness:
Front (lower, sloped): 85 mm
All other front: 200 mm
Side, vertical: 85 mm
Turret side: 85 mm
Lower vertical plate: 50 mm
Roof, including driver and radio operator hatches: 45 mm
Roof above the engine and air intake hatch: 45 mm

Observation devices and ports:
There is a periscopic observation device above the driver. There is a removable panoramic sight for the gun on the roof of the turret. There are openings for personal weapons.

The front part of the SPG has hatches for the driver, radio operator, two engine compartment hatches, and two gas tank hatches. The roof has 3 hatches, and 2 small hatches in the corners. The rear plate has a large hatch, and a small hatch in it.

Two Maybach gasoline engines, with 300 hp each, are located behind the driver. The engines are equipped with generators.

Gas tanks and radiators:
550 liter gas tanks are located next to the engines. The radiators are located next to the generators.

The rear wheel is the drive wheel, there are 6 road wheels per side.

Gun: 88 mm
Ammunition: 70-90 rounds
Machine gun: MG-42
Ammunition: 2000 bullets"

The next three pages are diagrams that I have already translated in the linked article. After that is a pretty self explanatory part (shoot at the gun and observation devices to make the SPG useless), a table of everything we learned in the previous part, and some credits.

The very last page has a picture of how one would place AT mines on a Ferdinand's path ("use mobile AT mines") and some words of encouragement: "Artilleryman, tanker, tank hunter! Bravely let the Germano-fascist Ferdinand SPG approach, coolly aim, and surely strike at weak points! Tanker Lieutenant A. Erohin destroyed 6 Ferdinand SPGs. Comrade Erohin, with brave and decisive ambush maneuvers, destroyed Ferdinands in battle by opening fire from 500-1000 meters at their engines and gas tanks."

Thanks to the magic of the Internet, Erohin's memoirs are readily available. This is what he writes on his encounter with Ferdinands:

"It wasn't a tank, it was like a giant box. It was powerful, I could tell by the way the shells flew... Their battalion started taking up positions to support infantry. Behind the column of smoke, several more of these vehicles approached. One tried to get up a hill, and the entire company opened fire at its side. It stopped. The rest turned around and opened fire at us. After obtaining my commander's permission, I went in from the flank, behind hills and bushes. Peeking out from behind a hill, I fired five times at  the closest tank. It started smoking. The rest started backing off. Their turrets could not turn, and my flanking maneuver put them in a bad position. If they turned to fire at me, they would become vulnerable to our other tanks, and currently, they were vulnerable to me. Soon, it became dark, and the German attack failed."

Considering that his tank was a plain T-34-76, Erohin did pretty well. Here are some excerpts from his award orders:

"Over three days [Note: July 5-7, 1943] Lieutenant Erohin and his courageous crew destroyed 3 Tiger tanks and 10 Germans"
"On November 2nd, 1943, comrade Erohin met an ambush of enemy SPGs. In an uneven battle, he went for a flanking maneuver, and destroyed four SPGs from the rear."
"On November 5th, 1943, in battles for the village Sinyak, the enemy offered heavy resistance, delaying our advance. Comrade Erohin, on his tank, bravely penetrated the enemy defenses, destroying enemy soldiers and equipment. During the battle, he destroyed 128 soldiers and officers, two light tanks, one gun, and four machine guns. For courage and heroism in the fight with German invaders, for the destruction of enemy soldiers and equipment, comrade Erohin is worthy of the title of Hero of the Soviet Union."

Sunday 22 December 2013

World of Tanks History Section: Ferdinand

On April 20th, 1942, Hitler was shown experimental heavy tanks developed by Henschel and Porsche. They impressed the fuhrer, and he gave the order to mass produce both. However, a series of reasons forced the choice of Henschel's model exclusively. At the same time, the need for a self propelled mount for the Rheinmetall 88 mm PaK 43 arose. The project required 200 mm of front armour, and limited the mass at 65 tons. Unused Porsche chassis served as a basis for the SPG.

Work started in September of 1942. The project was developed by Porsche and Alkett. Due to the long gun, Porsche selected a rear casemate placement, and engine placed in the middle. There is an opinion that the chassis was reversed. That opinion is false: both the tank and the SPG "looked" in the same direction. This can be seen by looking at the drive wheel: in both vehicles, it is in the rear.

In February of 1943, Hitler personally named this vehicle "Ferdinand", in honour of its creator. On February 16th, 1943, Nibelungenwerke started producing Porsche's creation.

The casemate of the SPG consisted of a truncated four-faced pyramid. It was made with cemented naval armour. The front armour of the hull, initially 100 mm thick, was reinforced with another plate, which was held on with rivets. The side and rear armour was thinner: only 80 mm. The rear of the casemate had a round hatch for removing the gun, loading ammunition, and emergency crew evacuation.

The gun opening was covered with a pear-shaped mantlet. It was quickly discovered that this was a poor solution, since when the mantlet was hit, small shards and molten metal droplets entered the vehicle. To mitigate this, nearly all Ferdinands got a square armour plate welded to their mantlet.

Because the fighting compartment was in the rear, and engine in the middle, the crew was separated. The casemate had the commander, gunner, and two loaders. The front had the driver and radio operator. The compartments were separated with metal walls, which made using an internal communication system necessary.

The thick armour and powerful gun made the Ferdinand a dangerous enemy. Its shells could penetrate Soviet tanks from 1000 meters, while Soviet tanks had to get much closer, or the German armoured monster would be invincible.

However, nothing is ideal. Porsche's creation was too heavy, had poor off-road performance and mobility. Before every mission the route had to be thoroughly scouted.

If you examine memoirs, you will find that Ferdinands were produced by the thousand, and fought on every section of the front. In reality, only 90 were built, and the only massed use of them was at the northern part of Kursk, next to the Ponyri railroad station and Teploye village, between two divisions.

The Ferdinands met their trial by fire there, and it was not an easy one. Armour played its part, and most losses were due to mine fields. Only one vehicle was met with concentrated fire from seven Soviet tanks and a 76 mm gun battery, and was found with a breach next to its drive wheel. Three more Ferdinands were destroyed by hits from an incendiary bottle, large caliber howitzer shell, and a direct hit from a bomb, respectively.

The only Soviet vehicle capable of fighting the Ferdinand one-on-one was the SU-152. They knocked out four Ferdinands in one battle.

After Kursk, Ferdinands were recalled to France and Austria for repairs and modernization. One of the most important changes was a machine gun in a ball mount in the front of the hull. Previously, the vehicle had no defense against infantry, and this could prove fatal in real combat conditions. A commander's cupola was added, and the mantlet shield was flipped, welding seams out. This made it easier to attach. The ammunition capacity increased to 55 shells. The SPG was renamed to "Elefant", but it was more frequently called by its original name, "Ferdinand".

Despite relatively few Ferdinands fighting in the Eastern Front, they became a bit of a legend. Any German SPG could be called a Ferdinand, even if it looked nothing alike. Also, anyone that destroyed a Ferdinand would receive an order, which caused many to assign themselves such a notorious victory.

An attempt to use Ferdinands in 1944 in Italy was a failure. 11 vehicles were sent there, but it turned out that local ground is not suited for them. The SPGs sank under fire, and the Germans had no chance to evacuate them due to constant artillery fire. Several vehicles were knocked out by American aircraft. On August 6th, only 3 Ferdinands returned to Austria.

On May 1st, 1945, two last Ferdinands were captured by Soviet and Polish soldiers during battles near the Karl-August square.

Original article available here.

The Last TK

These are photographs of a Polish TK-3 tankette. Fans of this particular type of vehicle might recognize it as serial number 194, with the proper name "szwadron śmierci" ("Death Squadron"). It was built on July 20th, 1936. Initially, it was used by the 10th Armoured Cavalry Brigade (10 Brygada Kawalerii Pancernej), but then it was captured by Soviet forces, along with 18 other Polish tanks and tankettes, and 2 German tanks. Two TK-S tankettes were sent to Kiev, where #194 was restored for testing, and eventually ended up in Hangar #7 (captured vehicles) at the Kubinka Tank Museum. 

CAMD RF 38-11355-12

"Technical Inspection Act

On January 14th, 1941, a commission consisting of chairman Military Engineer 2nd Grade comrade N.S. Salmin, and members Intendant-Technician 1st Grade comrade I.I. Stepanov, and Junior Military Technician comrade V.P. Gornih, as a result of orders from the assistant chief of the proving grounds, Military Engineer 1st Grade, comrade Gluhov, inspected a TK-3 (Polish tankette, #1621/109) for the purpose of recycling it as special metal and removing it from the proving grounds inventory. 

After familiarizing themselves with the proper documents and inspecting the vehicle, it was discovered that:
  1. The TK-3 Polish (captured) tankette that arrived at the proving grounds from repair base #7 was disassembled for parts in order to repair two TK-3 tankettes, #194/1725 and #128. The following parts were removed:
    1. Engine
    2. Side friction clutches
    3. Two fan covers
    4. Water cooling radiator
    5. One fan
    6. Driver's hatch
    7. Towing equipment
  2. The commission concludes that the hull of the tankette may be sent to the factory as coloured metal and removed from the inventory of the GABTU KA proving grounds."
#194 remains the only TK tankette with all original parts.

Saturday 21 December 2013

German Paint

We've seen trials of German tanks, trials of German guns, now it's time for something a little different. A trial of German...paint!

CAMD RF 38-11355-4

"To the chief of the Directorate of Armoured and Tank Forces of the Red Army, Military Engineer 1st class, comrade Korobkov.

As a part of a series of foreign purchases by the Red Army UVHZ, we received three types of oil and fat resistant "R-series" paints for armoured cars from the Herbig-Haarhaus factory:
  • Red-brown R-1 for primer
  • Khaki
  • Ivory R-13 for surfaces
Of these paints, we can allot the following amounts to BTU KA:
  • R-1: 2550 kg
  • Khaki: 1260 kg
  • R-13: 1258 kg
Attached are the Conditions of Delivery and instructions for using these paints. Please reply with your confirmation and indicate which warehouse to send the paints to.

Attachment: 3 pages of German text.

Deputy Chief of the Red Army NIHI, brigade engineer Korolev
Chief of the information division, military engineer 3rd class, Kondratyev
November 27th, 1940"

Friday 20 December 2013

BR-23 450 mm Howitzer

CAMD RF 81-12104-38

"To the Deputy People's Commissar of Defense and Head of GAU KA Marshall of the Soviet Union, comrade Kulik.

In 1940, factory #221, based on AU's tactical-technical requirements, developed a project of a 450 mm howitzer, which was approved by ZhAK #0012-40g. 

In the same year, the factory developed a technical project, which was examined and approved for the production of working blueprints.

The journal for examination of this technical project is composed, but still not approved by you.

The factory, not waiting for approval, began, and has almost finished, the creation of working blueprints. 

The UVNA GAU plans for 1941 include an experimental 450 mm howitzer, but due to the unconfirmed nature of the situation, the contract has not been signed and production has not started. 

I am reporting this, and waiting for further instructions on whether or not to sign a contract in the current year for the production of a 450 mm howitzer prototype and ammunition for it.

Chief of the UVNA GAU KA
Military engineer 1st grade, Lipin."

The document is dated February 1st, 1941. There was not enough time before the start of the war to develop such a massive device, but a model was built.

And here's some more technical data:

The artillery unit is transported on 7 25 ton railroad carts (the total mass of the system was "only" 110 tons). The rate of fire was 1 shot every 5 minutes. The gun fired two shells: one concrete penetrating (projected to penetrate 3 meters of reinforced concrete at 9.5 km), which weighed 1500 kg and contained 150 kg of explosives, and an HE grenade (projected to create a crater 230 cubic meters in size), which weighed 1060 kg and contained 159 kg of explosives.

Thursday 19 December 2013

World of Tanks: Today in History: Happy Birthday, T-34

Experience in the Spanish Civil War demonstrated that the era of tanks with bulletproof armour has come to an end. These tanks were a perfect target for light and fast-firing anti-tank guns. Engineers were tasked with making a tank with shell-proof armour.

In 1937-1938, Kharkov factory #183 worked on the A-20 covertible drive tank project, armed with a 45 mm cannon. At the same time, the engineers worked on another project on their own initiative: a tracked vehicle with thicker armour, indexed A-32. It was to be equipped with a 76 mm gun and a V-2 diesel engine.

The engineers managed to prove to the army that the A-32 has promise, despite the latter's preference for the convertible drive. The tracked vehicle had better off-road performance, the diesel engine was more fuel efficient and, at least in theory, more reliable than the gasoline engine. The armament was also better than on the A-20. After government trials in 1939, the tank was renamed T-32, its armour was strengthened, and it was equipped with a 76 mm L-10 gun.

In September of 1939, the T-32, among others, was presented to a government commission which included K. Voroshilov, A. Mikoyan, and A. Zhdanov, among others. The vehicle was driven by N. Nosik. The tank performed well. On December 19th, 1939, the Committee of Defense in the Council of People's Commissars announced decree #443, which accepted the T-34 (the new official name of the tank) into service with the RKKA.

Aside from acceptance into service, decree #443 listed changes to the design. The army wanted better visibility, 45 mm armour, and replacement of the L-10 with a cheaper and better designed F-32. Two prototypes of the T-34 were to be built by January 15th, 1940.

A great and difficult journey awaited the T-34. The vehicle was contraversial and far from ideal, as was any tank in WWII. For us, it will always be a tank of victory, a symbol and legend of the RKKA armoured force.

Original article available here.

From Tank to Infantry

"Mechanic-driver of the 2nd tank battalion of the 10th tank brigade, Junior Sergeant Alexey Savvich Bulba

  1. Year of birth: 1921
  2. Nationality: Ukrainian
  3. Social position: Student
  4. Party affiliation: VLKSM member
  5. In RKKA since: 1940
  6. Participated in the civil war: fighting German fascism
  7. Wounds and concussions: none
  8. Prior award recommendations, if any: none
  9. Prior awards and commendations, if any: none.
Brief summary of personal heroic deed in combat:
From the very start of the Great Patriotic War, BT tank driver comrade Bulba showed courage, as a true son of the great Russian people. He drove into battle in his menacing vehicle many times.

Comrade Bulba performed his heroic deed in battle for the Volobuyevka settlement. The Germans considered Volobuyevka an impenetrable fortress. 

Driver Bulba drove his tank along with his unit. As he approached the outskirts of the village, he saw that one of the houses was a reinforced hardpoint. He alerted the tank commander, and decided to ram through the side of the building. After a strong impact, the vehicle penetrated turret-deep into the house, but was shot, and caught fire. Comrade Bulba opened the hatch, and shot three soldiers point blank. The rest panicked and fled. Comrade Bulba left the house and joined the infantry escort. With a rifle in hand, he continued pursuing the fleeing enemy. In this battle, comrade Bulba's tank destroyed 2 machine guns and up to 40 enemy infantrymen.

In combat for Peremoga, comrade Bulba once more courageously drove his tank into battle, and destroyed up to 35 enemy soldiers and officers. After his tank was damaged by an enemy shell, he managed to recover it from the battlefield. He is worthy of a government award, the Order of the Red Banner."

Wednesday 18 December 2013

MS-1 Restoration

A while ago, I posted an article on the history of the MS-1, which mentioned that MS-1 tanks that exist today, survived as "legless" bunkers. Therefore, they no longer had original suspensions. Various MS-1s that are installed as monuments had their suspensions rebuilt, with mixed results. A reminder: the original suspension of the MS-1 looks like this.

LiveJournal user bf_109e took a photo of the following MS-1 in Vladivostok.

Well, uh, at least they tried. The garish green colour is, sadly, seen on a number of other monument tanks. The suspension is not even remotely similar to the original. Closer inspection reveals that it does not even have road wheels, only what appears to be a stamped metal bit with round ends. This MS-1 isn't going anywhere any time soon. The gun also suffered the restoration process (few MS-1 bunkers retained their original guns).

LJ user kamikadze1993 posted pictures of three MS-1s in Khabarovsk. The first one isn't that bad.

The number of shock absorbers and road wheels is correct. Something that appears to be torsion bars was added, but surely we can overlook such a minor detail, especially since the gun is a lot more reasonable and the colour isn't hideous.

Kind of primitive, but better than the first one! At least this one actually has wheels.

Aaaaahhh! What is this? And they couldn't even bother to put some sheet metal where the track covers used to be? How terrible. Although, maybe I can start some rumours of a Christie suspension MS-1...

But it only gets worse! This one is in an actual museum, at the Lenino-Snegiryev museum in Istra. 

The suspension isn't the worst so far, but some, er, liberties were taken with the rest of the tank. The cannon is where the machine guns should be and the commander's cupola looks like a pot.

And here is a unique example of an MS-1 in working order. This one is located in the Kubinka tank museum, and its suspension looks pretty decent.

The vehicle was found in parts, so it's hard to judge its condition, but the deficiency in the suspension is obvious even when the tank is not moving. The middle shock absorber is missing, and the road wheels are connected to a horizontal bar. This is even more obvious when the vehicle is in motion: not all of the road wheels rotate very well.

Tuesday 17 December 2013

Mix and Match

The Soviet practice of making monuments out of military surplus is quite widespread. In nearly every town, no matter how small, there will be some kind of monument to the fighting that took place there, with a cannon or a tank. However, sometimes the tank on the monument is a mix and match of tank parts, some of which don't even belong on the same tank. For example, a photograph of a tank at Parfino (credit to LiveJournal user wadimych):

While a casual passerby might see nothing but a tank, an expert would swiftly detect an anomaly. Why, that's clearly a KV-1S turret on a KV-1 hull! What are they trying to pull here? However, upon further inspection, the plot thickens.

A German AT gunner made his mark here, with a shell that managed to strike the hull and turret, before bouncing off harmlessly. This means that this tank, as a whole, saw combat. But how could this be? The answer, as always, lies in the archives.

RGASPI 644-2-102

"Comrade Stalin
Comrade Molotov

By the order of the GKO, the Kirov factory has been producing KV-1S tanks that weigh 41.5-42 tons with improved components since August.

Due to the higher T-34 production quotas and cessation of shipments from factory #264 (Stalingrad), it was decided to increase the production of T-34 hulls at Uralmash and transfer the production of KV hulls to factory #200.

In September, factory #200 increased KV hull production nearly twofold. In order to match the plan, factory #200 needs to produce twice as many hulls in October as it did in September. 

Despite measures that were taken, the production is behind schedule. 

In order to meet the production quotas for KV tanks in October, I ask of you to allow the use of KV hulls with side armour thickness of 75 mm.

The GOKO decree is attached.

People's Commissar of Tank Manufacturing, I. Zaltsmann."

RGASPI 644-2-102

"The State Committee of Defense decrees that the Kirov factory is allowed to produce 100 KV tanks with thickened side armour (75 mm) to meet October quotas.

Chairman of the State Committee of Defense, Molotov"

In total, 70 of these hybrids were produced. 8 were sent to the 9th Guards Regiment at Kubinka, 16 to the 10th Guards Regiment at Kosterovo, 3 to the Ulyanov academy, 34 to the 12th Guards Regiment at Noginsk, 9 to the ZKU, and 7 to the Amoured Car and Tank Center at Lubertsy. The serial numbers of these vehicles are available in CAMD RF 38-11355-887, "Notice of accepted and sent KV-1S tanks with heavy KV-1 hulls".

Sunday 15 December 2013

IS-4 Start to Finish

The IS tank, released in 1943, had 120 mm of front armour, compared to its predecessor's 75, in roughly the same configuration. However, while the KV's 75 mm rendered it nearly invincible against all modern anti-tank guns, the IS did not have such luxury. Work on an IS tank with superior armour began during that same year.
"K" Heavy Tank, a precursor project to the IS-4.

CAMD RF 38-11355-2189
The above is a fragment of the blueprints of the first Object 701, with a clear date: December 1943. Sadly, Kirov factory must have been short on paper, as they used the backs of early 701 blueprints for scrap in 1944. 

Object 701 was a lofty goal indeed. It was designed to be impenetrable to the most powerful anti-tank guns of the day, the D-25 and KwK 43. As we've seen from a previous article, the tank eventually achieved that objective. However, early prototypes of the hull had a couple of weaknesses.

CAMD RF 38-11355-2411

"Photo #20. Penetration of the spherical cover of the TSh-17 sight with 88 mm armour piercing shells. Penetration of the driver's observation device with 88 mm shells.

Due to the spherical shape of the sight cover, a hit at a perpendicular angle, and therefore penetration, is possible at various angles. The rolled roof of the tank can be penetrated by 88 mm shells (see photo #19).

The cover of the driver's observation device can be penetrated by 88 mm shells (see photo #20). The factory used 8S steel, which cannot be properly conditioned when over 75 mm thick. Kirov factory representatives insist that use of this grade of steel was unavoidable.

The turret platform roof is penetrated by the shockwave of an HE-fragmentation 122 mm shell."

Well, the tank is mostly protected. Can't penetrate the upper glacis (shot 59 barely dents it), but the weak spots require a redesign. Let's look at how the rear armour fared.

CAMD RF 38-11355-2411

"Photo #9. Intact connections between the rear hull sides and hull rear, as well as the upper rear plate and lower rear plate after concentrated fire by 75 and 88 mm guns armour piercing shells."

Impressive! The guns cannot even penetrate the rear armour of the tank. The sides, however...

CAMD RF 38-11355-2411

"Photo #10. Rear side hull separated from the front side hull after welding seam was destroyed."

A lucky hit to the welding seam can penetrate the hull side, otherwise it performs very well. The tank's armour proves worthy, but the design of the hull needs some work. 

That was Object 701 #1. Objects 701 #2 and #3 had improved welding seams and higher hardening of the turret armour. The test results greatly improved as well: "The armour of the Object 701 tank provides complete protection from 75 and 88 mm shells with muzzle velocity of up to 1000 m/s at any distance, in an arc of +/- 60 degrees from the front of the hull and +/- 30 degrees from the front of the turret." As a result of these trials, the hull and turret designs of the Object 701 were accepted. Object 701 #5 and #6 later had the front plate increased to 140 mm to counter potential 105 and 128 mm guns.

The drivetrain needed some work, though. Object 701 #4 received an improved transmission, which was further improved in #5 and #6 prototypes.

As for the armament, the gun was the same old D-25 that has proven itself against the toughest German armour

"According to your requests, the Chebarkul GAU proving grounds tested the 122 mm tank gun model 1943 (D-25) in the new heavy tank (object 701), developed by the Kirov factory, between May 11th and 15th of 1945. 

In total, 403 shots were fired. The trials established that:
  1. The precision of the gun at 500, 1000, and 2000 meters is satisfactory.
  2. The angle of incidence of AP and HE shells is the same, -2.9 minutes, nearly identical to the calculated angle (-3 minutes).
  3. The practical rate of fire is 2-3 RPM, and peak is 3-4 RPM.
    The main complaints in the process of trials were about the fighting compartment equipment and gun installation.
    1. The three propellant casing holder on the right side of the turret is impeded by the signal flare box and machine gun ammunition box.
    2. The elevation mechanism carrier was crooked.
After the removal of the above deficiencies, especially after increasing the robustness of the elevation mechanism carrier, trials as to be repeated.

The 122 mm tank gun trialled in May of 1945 was produced in April-May of 1944. After that, the gun was substantially modified and improved. Most importantly, the gun's semi-automatics were improved, removing the possibility of breaking the breech opening roller pin. All other downsides of the gun can be explained by quality of production

Deputy chair of the AK GAU KA, Major-General of the Artillery Engineering Service, Zhevanik"

One of the modifications to the gun in that time must have been Kotin's loading assistance device, which increased the peak rate of fire on the IS-2 to 6 rounds per minute. 

However, May 1945 marked the defeat of Germany. Fighting the Japanese would not require a powerful new tank, and it was unclear what it would be used for, if anything. Engineers and equipment was needed for peacetime duties. Here are some excerpts from a Kirov factory report for the first quarter of 1946.

"All the best and most precise equipment was moved from tank-building plants to tractor building plants.
The remaining equipment is from before the War, and did not have proper service since then, and therefore, 40% of it requires medium or major repairs. 
The best tank engineers, plant managers, technologists, foremen, and highly qualified employees were transferred to tractor production. For example: out of 212 tank engineers, 112 remained by January 1st, 1945, and 66 remain as of January 1st, 1946. The 146 employees were transferred to other positions, including managers and production line foremen.

The remaining 66 engineers perform the following duties. 16 engineers develop new objects, while 50 of the less qualified engineers work on Object 701 and production of the IS-3 tank. 

This is insufficient for preparation of the 701st for production. The number must be increased to 100 engineers. 
There used to be 470 controllers and 7839 employees in the 11 tank building plants as of June 1st, 1945. These numbers are now reduced to 5 plants, 198 controllers, and 3358 employees. 

The employees are new, and had to familiarize themselves with the new technologies in April-May, leading to lower quality of joints and installations of IS-3 components. "
CAMD RF 38-11355-3130

The IS-4 was cancelled after production of just over 250 units. The heavily armoured sluggish behemoth of old was incompatible with the modern maneuverable war, especially with the looming threat of nuclear escalation.