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Nashorn Notes

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"On firing positions for 88 mm SPGs (Nashorn, formerly Hornisse)
  1. During use of self propelled anti-tank guns, it is important to perform thorough reconnaissance (preferably on foot). Frequently, the neighbouring section of the front turns out to have more favourable conditions for firing and ambush positions. In that case, the commander of the anti-tank unit must apply them in the neighbouring sector, and not in his own. The specifics of this weapon require certain flexibility in its use. The only important thing is that it must function as effectively as possible.
  2. To make it harder for the enemy to fight these thinly armoured SPGs and to conceal the main direction of anti-tank defenses, it is necessary to change positions more frequently.
  3. On observation and fire correction of direct firing guns: observation and fire correction is made extremely difficult by sand, dust, or snow kicked up by firing the gun. Conclusion: observation positions must be prepared 15 meters to each side of the gun. Depending on the direction of the wind, the commander observes from the right or the left observation point."

Birth of the SU-152

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"State Committee of Defense decree #2883ss
February 14th, 1943
Moscow, Kremlin

On the production of SU-14 SPGs, KV-1S tanks, and armoured hulls for them in February and March of 1943

In order to satisfy SU-14 production requirements set by GOKO decree #2859ss issued on February 9th, 1943, as well as to ensure production in March, the State Committee of Defense decrees that:

1. The People's Commissar of Tank Production (comrade Zaltsmann), director of the Kirov factory (comrade Dlugach) and director of factory #200 (comrade Sherbakov) must:
  1. Immediately begin production of SU-14 152 mm SPGs and hulls based on blueprints sent on January 30th, 1943, and comments from the State trials commission made in the report issued on February 7th.
  2. Provide for the production of SU-14 SPGs and KV-1S tanks in February of 1943 based on the requirements in GOKO decree #2859ss issued on February 9th, 1943, and in March based on partially amended amounts fompared to GOKO decree #2693ss published on January 4th, 1943:


February 1943
March 1943
SU-14 SPGs
30
75
KV-1S tanks
75
50

Also, produce hulls for SU-14 SPGs and KV-1S tanks at factory #200 in February and March:


February 1943
March 1943
SU-14 hulls
35
100
KV-1S hulls
75
40
2. Red Army GAU (comrade Yakovlev) must approve the blueprints and technical requirements for the SU-14 SPG with correction of defects that are discovered during production of the February and March production run by March 20th, 1943.

3. The People's Commissar of Armament (comrade Ustinov), director of factory #172 (comrade Bykhovskiy) and #69 (comrade Kotlyar) must:
  1. Supply the Kirov factory with ML-20 artillery systems with frames, elevation mechanisms, and turning mechanisms (factory #172) and optics (factory #69) matching the samples for the experimental SU-14 in the following amounts:

    Total
    1-10th
    10-15th
    15-20th
    20-28/31st
    February
    50
    -
    5
    15
    30
    March
    75
    25
    12
    13
    25
  2. Produce enough frames at factory #172 to match the amount of ML-20 guns received at the Kirov factory.
  3. Send 10-15 designers and installers to the Kirov factory for February and March of 1943 to install the ML-20 guns.
4. The People's Commissar of Tank Production (comrade Zaltsmann) must produce castings for an experimental batch of frames for the ML-20 gun out of Bessemer steel and deliver them to factory #172 by February 22nd, 1943.

5. The People's Commissar of Armament (comrade Ustinov) and GAU (comrade Yakovlev) must perform trials of the Bessemer steel frame and determine if it is usable in the SU-14 SPG to hold the ML-20 gun.

6. The People's Commissariat of Tank Production (comrade Zaltsmann) must, given the go-ahead from the People's Commissar of Armament and the GAU, arrange for casting at factory #40 in March and April and delivery to factory #172 in amounts sufficient to produce enough ML-20 guns to satisfy the production of the SU-14 at the Kirov factory.
If it is impossible to produce Bessemer steel frames, produce them from special steel at the factories of the People's Commissariat of Armament.

Chairman of the State Committee of Defense, I. Stalin"

AK Accessories

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The accuracy of an automatic weapon is important, and many experiments were run on the AK platform to figure out if it can be increased. A number of experimental muzzle devices were built for this purpose. _tezka provided this picture.

Left to right: similar to stock type, brake-compensator, two chamber, flash suppressor, single chamber, reactive.

While all of these successfully reduced muzzle climb and improved accuracy, there was one important drawback that engineers did not necessarily consider...

"The positive effect of the muzzle brake on the accuracy is at odds with the negative result of the sound wave hearing, which is greatly increased to unacceptable levels with most muzzle brakes.
...
The evaluation of the effect of the sound waves on hearing reveals that all muzzle brakes in the table result in a bothersome or painful sensation in the ears."

A DShK style reflector was considered to remedy this effect, but...

"...a reflector of such size can hardly be recommended as they decrease the maneuverability and comfort of the weapon and do not achieve the intended result of reducing the sound to a level that does not cause pain."

Another device was tested to improve accuracy, but it was a different kind of brake.



Curiously enough, it was a brake for the bolt. The experiment was meant to determine the effect of the speed of the bolt flying back and forth on accuracy. The knobs on the sides could adjust the force applied to the bolt in order to slow it down.

British Primer Minister in the USSR

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Winston Churchill, the British Prime Minister, visited Moscow in August of 1942. However, a Churchill arrived a month prior to that in another Soviet city, Archangelsk, with the PQ-17 caravan, and not just one. These, of course, were Churchill II and III infantry tanks. 301 tanks of this type were sent to the USSR, 253 of which arrived at their destination. Despite a rather small volume of shipments, the prime minister's namesake played an important role on the battlefields of the Great Patriotic War. Suffice it to say that these tanks, along with the KV-1S, were the primary heavy tanks of the Red Army during the Battle for Prokhorovka.


Discredited by its own

The USSR learned of the existence of Churchill tanks in October of 1941. According to the information prepared for the Information Department of the Red Army General Staff Intelligence Service, the British began producing the Infantry Tank Mk.IV or Churchill since the spring of 1941. Later Soviet documents refer to this vehicle as the MK-IV. The report contained correct characteristics of the tank, including information on the mass and armament. Soviet intelligence also learned that the British were planning to install a 57 mm gun in place of the 40 mm 2-pounder in the turret. The production volumes were also correctly estimated. The top speed, estimated at 35-38 kph, was incorrect. The Churchill could only reach that speed from the top of a very steep hill.

Aside from the Churchill, the report mentions a British 70 ton heavy tank armed with three cannons and six machineguns, with a crew of 11. This could have been an echo of the TOG.

The first document dedicated to shipments of Churchill tanks to the USSR.

The issue of shipping tanks Churchill to the USSR was not raised until the spring of 1942. However, these vehicles were mentioned frequently in correspondence. In addition, Soviet military representatives toured factories where these tanks were built. Among others, a Soviet delegation visited the Old Park Works Wednesbury factory in Birmingham. This factory was owned by the Midland Railway Carriage and Wagon Company. According to the commission's findings, 6-7 Churchill tanks were made here per week. In February, the Soviet military representatives visited Vauxhall, the chief developer and producer of Churchill tanks. This factory built 10 Churchill tanks per week. The commission also visited the Leyland factory on April 28-30th, which they estimated produced 7 tanks per week.

The Soviet commission ended up visiting three of the four factories that Churchill tanks were built at. In addition, they were able to attend Churchill IV trials, even though the tank was just entering production.

Soviet military mission representatives at Churchill IV trials, England, spring of 1942.

The first negotiations regarding shipment of British heavy tanks to the USSR began in March of 1942. The volume of supplied parts and ammunition per tank was discussed. Interestingly enough, the Churchill III was supposed to come with 135 HE rounds. This kind of ammunition was not in production in Great Britain at the time. Later, this deficiency will come up in documents regularly.

The British finally settled the volume of shipments towards the end of April. Churchill tanks would replace shipments of the Matilda. Initially, the USSR would receive 25 tanks. Of those, 23 were Churchill II tanks, equipped with 2-pounder guns. One can say that the British were getting rid of outdated tanks with armament that was worthless by the spring of 1942. Production of the Churchill III, a greatly improved model with a roomier turret and a 57 mm 6-pounder gun, began in February of 1942. Gradually, the amount of Churchill III tanks supplied would increase. The second shipment would only contain 21 Churchill IIs.

The tanks sent to the USSR would also be modernized to correct discovered defects. On these tanks, the five digit registration number was followed by the letter R (Remanufactured). Interestingly enough, Soviet representatives declined reception of British instructions along with the tanks. First of all, Major (later Colonel) Kovalev already familiarized himself with the tanks when he was touring British factories. He was urgently recalled to the USSR to participate in the acceptance process. Second, the instructions and documentation for these tanks were already translated.

A list of tanks that arrived with PQ-17. Out of 25 tanks sent with this convoy, only 10 arrived at their destination.

Shipment of the first batch dragged on for several months. In that time, the ratio of the modifications changed. 10 Churchill III and 15 Churchill II tanks were sent. Convoy PQ-17 departed on June 27th, 1942, carrying 25 British heavy tanks. The German assault on this convoy directly impacted the number of Churchill tanks that arrived. Out of all transports that were carrying tanks, only the Ocean Freedom survived. It arrived in Arkhangelsk on July 11th, carrying 5 Churchill II and 5 Churchill III tanks.

A long pause in shipments followed the destruction of PQ-17. The next batch of tanks arrived with PQ-18, which arrived in Arkhangelsk on September 21st, 1942. This time, 74 Churchill tanks reached their destination. This convoy was the last to carry Churchill II tanks. British sources claim that 45 Churchill II tanks were sent to the USSR, of which 26 made it to their destination. This figure is not entirely correct. Out of 74 tanks that came with PQ-18, only 15 were Churchill II. Overall, 20 tanks of this type arrived, 19 of which were sent to the 50th Guards Heavy Tank Regiment. One tank was sent in the 194th Training Tank Brigade.

One of two known photographs of a Churchill II tank in the Red Army. The vehicle belongs to the 50th Guards Heavy Tank Regiment.

The destruction of PQ-17 was just the first of a long series of misfortunes to befall the Churchill in the USSR. Troubling news began coming from England just as the first tanks were unloaded in Arkhangelsk. Engineer-Colonel Kovalev reported that 6-pounder tank guns have issues with their elevation mechanism. One vehicle had this issue discovered during unloading. While driving in Bakharitsa, the vibration resulted in a cracking of the case of the turning mechanism. Formally, the fault fell on Military Technician 2nd Class I.F. Lolenko, but the real culprit was the British, who did not warn about this known defect. Another issue was with the fenders. They were dented on half of the tanks that were unloaded.

The constant breakdown of the engines was a bigger issue. This problem was caused by the modernization of the tanks, and the British knew about it. The destruction of PQ-17 meant that there was a shortage of spare parts, which resulted in one of the tanks becoming unserviceable by the end of August. Another issue was that a British Churchill expert never arrived. Even though the Soviets protested, the British appointed Captain Remington to accompany the tanks, but he was captured by the Germans. Captain Cox was appointed in his stead, and arrived in the USSR with convoy PQ-18.

One of the Churchill III tanks that were undergoing trials at the NIBT proving grounds, August 1942.

The British themselves caused additional issues with the tank. In October, the Soviets were given access to correspondence regarding the development and evaluation of the tank by the British military. The tank was built through considerably difficulty. This is not unusual for any tank built from scratch, but it's hardly a wise decision to make this information available to your customer. Soviet specialists also obtained correspondence regarding further development of the tank. It considered various variants, including the development of a completely new tank.

This kind of information did not increase the level of trust from the Soviet side. In addition, it was discovered that 55 Churchill III tanks delivered on PQ-18 had recoil brake defects. Soviet military acceptance counted 9 distinct defects in the shipment. Factory #92, among others, was tasked with correcting them. It's not surprising that Churchill tanks only went into battle in 1943.

The tank carries notices that the cooling system is filled with antifreeze.

Despite these unflattering reports, shipments continued. On January 27th, 1943, convoy JW-52 arrived in Murmansk, carrying 40 tanks. This delivery was counted for February. It included both Churchill III and Churchill IV tanks. The difference of the latter was its cast turret. It turned out that casting was a more efficient method of production.

The biggest delivery of 121 tanks was received in March. These tanks arrived with convoy JW-53 in the end of February 1943. Shipments ceased after that, with another 8 Churchills coming in through Vladivostok only in August of 1943. Aside from these last few tanks, all other Churchills were delivered through the northern routes. Overall, 253 Churchill tanks were received, of them 105 Churchill IV.

An additional fuel tank can be seen in the rear.

The Churchill redeemed itself in British eyes in the spring of 1943. These tanks made an impact on the fighting for Tunis. Churchill tanks could confidently drive in mountainous terrain, supporting British infantry. In addition, tanks of the 48th Royal Tank Regiment knocked out a Tiger tank, which is now on display in the Bovington tank museum. Because of these battles, the Churchill was the only British production tank that remained on the front lines. They remained the most numerous British-built tanks until the end of the war, and even the Cromwell did not outnumber them.

Nevertheless, the British themselves influenced the cessation of shipments to the USSR. However, recall that the next Arctic convoy, JW-54, only arrived in the USSR in November of 1943. The significant break between convoys was the real reason that orders for the Churchill stopped. In addition, the Battle of Kursk made it clear that the tanks had insufficient armour and firepower.

Slow, thick-skinned, and powerful

One of the five Churchill III tanks that arrived in the USSR with PQ-17 was sent to Kubinka for trials. These were some of the first trials at these proving grounds since the NIBT relocated back to Kubinka from Kazan. The tank with W.D. number T.31222R was put through trials. However, they started out poorly. The tank broke down during a march from warehouse #511 to the proving grounds. It turned out that the liner between the upper right cylinder head and cylinder block was faulty. The damage was not discovered in time, since the tank was driving at night. As a result, the coolant leaked out, and the head and block cracked. This defect was also well known to the British.

Due to the breakdown, T.31221R took the place of T.31222R in the trials.

This serious engine defect put the rest of the trials in jeopardy. The tank was sent for repairs, where it was bogged down due to a lack of spare parts. As a result, it was decided to give another tank to the proving grounds, with W.D. number T.31221R. Since this tank would later be sent to the front, the trials program was shortened. Mobility and gunnery trials took place from August 30th to September 5th, 1942. The tank returned to the Gorkiy training center afterwards, where it was assigned to the 47th Guards Heavy Tank Regiment.

The tow cable stowage can be seen.

The tank was already used by the time it arrived at the proving grounds. It came from the Gorkiy training center, where it travelled for 200 km. Since it was known that it would return to service after the trials were completed, the amount of trials was minimized. Overall, the tank travelled 97 km on a highway and 87 on dirt roads, including a small section designed to test obstacle crossing. The tank used domestic B-70 gasoline with R-9 aircraft additives to boost the octane value. British instruction suggested using at least 75 octane gas.

The Churchill III had thicker front armour than the KV-1.

The tank's performance on the highway didn't surprise anyone. It was clear that this heavy vehicle, built to support infantry, could not drive very quickly. Nevertheless, the tank reached a top speed of 28 kph on a straightaway, which was acceptable for this kind of tank. This performance was 4 kph better than the official top speed. The average speed of the tank was 25.4 kph, which was comparable with the average speed of the KV-1 tank. The British tank was not all that slow.

One of the tank's features was the doubled driving controls. The Churchill also had hydraulic servos, which made driving it easy. Testers commented that the tank turned smoothly. The engine consumed 325 L of fuel for 100 km of travel, which was deemed acceptable.

Churchill III from the rear.

The tank behaved well on dirt roads. The average movement speed was 17.5 kph, with an average total speed of 16.8 kph. This was also comparable with the KV-1, which had an average speed of 18 kph. Fuel consumption was 382 L per 100 km. This meant that the range of the tank was 246 km on the highway and 166 km on dirt roads, which was also comparable with the KV-1.

The heavy tank performed well on uneven terrain.

Maximum grade testing was the last stage of the trials. Ravines near Agafonovo village on the Moscow river were picked for the trials. It was determined that the maximum grade on sand was 27 degrees, after which the tracks lost traction. On grades covered with grass and small shrubs, the maximum was 30 degrees. Testers noted that the tank maxed out its engine power in these conditions.

Trials showed that driving on an incline was not the Churchill's strong suit.

Driving on inclines was a whole different story. The maximum tilt was 20 degrees, after which the track slipped off. In general, the tank's suspension did not allow for this kind of driving. Two bogeys broke during testing, the gearbox selector rod broke several times, and track links broke a few times. Overall, Soviet specialists deemed the suspension weak for this kind of tank.

Visibility diagram. The tank performed well in this regard, especially when compared to the KV-1.

The tank's visibility received top scores. The driver was the blindest of the crewmen, as his vision was restricted by the protruding fenders. The assistant driver was in the same boat. However, the turret crew was a whole different story. Thanks to the Mk.IV observation periscopes, the crew could see perfectly, especially for such a large vehicle. The Vickers Mk.IV observation device was copied in the USSR after these trials, under the name "periscopic device MK-IV". Interestingly enough, in this case the new name did not refer to the original index, but to the fact that it was used on the MK-IV tank.

The PzIII's armour was no match for the 6-pounder gun.

Another part of the trials was firing on a German PzIII tank. An early production tank with 30 mm of armour was used. The 6-pounder shell penetrated the side from 950 meters and came out of the other end. It's worth mentioning that this was an early 6-pounder gun, the Mk.V, with a 43 caliber barrel. The trials were not without accidents. Gases from the barrel smashed the left headlight and bend the left fender. The semiautomatic mechanism broke on the 26th shot.

Trials also showed that the 50.8 mm bomb thrower on the tank could accept ammunition from the domestic 50 mm mortar.

Trials against a Tiger showed that the 6-pounder gun was underestimated. Unlike Soviet F-34 and ZIS-5 guns, it had no issues penetrating the side of the tank.

Despite a number of drawbacks, the "MK-IV heavy tank" was comparable with Soviet tanks. The commission called the Churchill "unfinished", and this is a fair assessment. On the other hand, along with obvious drawbacks, the tank had its advantages. This primarily includes its visibility, which was superior to that of the KV-1.

The firepower of the British tank was also underestimated. Firing on a captured Tiger tank in the spring of 1943 proved that. Soviet 76 mm F-34 and ZIS-5 guns could not penetrate the side of the Tiger from 200 meters. At the same time, the British 57 mm anti-tank gun, with identical ballistics to the tank gun, managed to penetrate the side of the hull from 1000 meters and the turret from 800 meters. Overall, the armament of the British tank was comparable to that of the Soviet ZIS-2 gun.

From Stalingrad to Tallin

The destruction of PQ-17 had an impact on the formation of units that were supposed to receive British heavy tanks. Churchills were confined to the 194th Tank Training Brigade until the end of September of 1942. It was formed in April of 1942 to train crews for British tanks. Aside from Churchills, it trained Valentine and Matilda crews. All Churchills that arrived at the Gorky center passed through the 194th brigade. In addition to training crews, it also revealed the tanks' defects.

Formation of new units began in October of 1942. British tanks of this type were included in Independent Guards Tank Regiments, formed to TO&E 010/267. The authorized strength of this regiment was 21 tanks and 3 armoured cars. The first regiments of this type were the 47th, 48th, 49th, and 50th Independent Guards Tank Regiments, formed on October 8th, 1942. The 50th regiment initially only had Churchill II tanks, but was later reinforced with two Churchill IIIs.

Churchill III tank from the 48th Guards Heavy Tank Regiment and its crew. This unit was the first Guards regiment to use the Churchill in battle.

The process of preparing the Churchills for battle was further proof that the evaluation of the tanks as "unfinished" was correct. The British tank had to be wrestled into fighting condition. For starters, defects of the 6-pounder gun were corrected at factory #92. Springs were replaced and recuperator cylinders bored out. All Churchill III tanks that arrived in 1942 had this modification performed.

Issues with engines did not go away, and had to be fixed at another factory in Gorky: GAZ. Cast tracks broke, as well as drive sprocket and idler axles, and the fuel lines. Another issue discovered in November of 1942 was the poor traction on ice and snow. These issues were solved in the field by the 47th regiment, which welded grousers onto the tracks of tank T.68768. Trials performed on December 21st, 1942, proved that this idea was correct. An order was given to convert all other tanks in a similar fashion. Another winter issue was the packing of snow into the fenders. After 8-10 km of driving, there was usually enough snow to tear the fender off completely.

Overall, the number of tanks with defects was not encouraging. In the 47th Guards Tank Regiment, 12 tanks had one issue or another, 16 tanks in the 48th regiment, 15 in the 49th, and 8 tanks in the 50th. It's not surprising that delivery to the front lines took so long.

Knocked out Churchill IV from the 48th Guards Heavy Tank Regiment. It was delivered in May of 1943 and lost during the defensive fighting at the Battle of Kursk on July 6-7th.

The 48th Guards Tank Regiment was the first to be battle-ready. It was assigned to the Don Front on December 31st, 1942. On January 16th, the tanks arrived at Kochalino station. On the 19th, they reached Pitomnik station, where they were placed at the disposal of the 21st Army. On January 21st, the regiment supported an attack by the 216th and 218th Rifle Regiments on the Gumrak station. The result of the first day of battles was the capture of the Gonchara homestead, 5 enemy tanks, 70 guns, 15 mortars, 20 motorcycles, and about 800 cars. The regiment's losses were 4 damaged tanks, 1 man dead, and 3 wounded.

The regiment attacked German positions at the outskirts of Gumrak on the next day. After a loss of two tanks burned up and 5 knocked out, the regiment returned to its original positions. January 23rd was spent repairing the tanks, and the attack was repeated on the next day. This time, the regiment, assisted by the 216th Guards Rifle Regiment, managed to complete their objective and take Gumrak. The Churchills capitalized on their success and chased the Germans for another 9 kilometers.

On January 29th, the regiment was assigned to the 93rd Guards Rifle Regiment. The new objective was to clear Stalingrad of German forces. Street fighting broke out, where the Churchills were often forced to crush enemy tanks with their tracks. The regiment destroyed 4 German tanks, 20 guns, 45 machineguns, and about 100 cars on January 30th alone. The regiment fought until February 1st in this fashion, capturing a total of 9 tanks, 50 planes, 1900 cars, and 90 guns. The regiment lost 12 men killed and 29 wounded during the fighting in Stalingrad. The losses in materiel were small: only 2 tanks were irreparably lost, the ones that burned up during that attack on Gumrak. 6 more required major repairs, and 13 needed light repairs. Considering that these tanks were mastered with great difficulty, it is not surprising that so many of them were in need of repairs.

The 48th was not the only regiment with Churchill tanks to fight at Stalingrad. The 47th Guards Tank Regiment, a part of the 65th Army since January 9th, was fighting nearby. It fought alongside the 91st Tank Brigade, 33th Rifle and 67th Guards Rifle Divisions. Towards the end of January, the regiment was fighting at the Barricade factory, with only 3 vehicles remaining in service. As with the 48th regiment, most of the vehicles were not lost completely, and just needed to be fixed up.

Churchill III from the 49th Guards Tank Regiment, Leningrad, winter 1943-44.

The next unit to fight on Churchill tanks was the 50th Guards Tank Regiment. It completed a march to the railroad station in Gorky on March 8th, and arrived at the Voybokalo station in Leningrad Oblast on the 16th. The tanks went on the offensive on March 19th. However, the tankers had to fight with their tanks more than the enemy. The first tank broke down on the march, the second burned up its clutch, two were bogged down in a swamp. 12 more tanks became bogged down during the attack, 2 of which hit mines. 2 tanks were knocked out by artillery. Two tanks reached enemy positions, one of which got stuck in a trench, and was later burned by the enemy. The attack was repeated on the next day with some of the tanks that were freed. In the first days of fighting, the tanks and infantry managed to push the Germans back.

The attack was repeated on the 22nd, and this time it became a real trial. Three tanks of five were disabled by mines. Guards Captain N.D. Belodub, the commander of the attack, remained in his tank with his crew. The crew fought from their disabled tank for four days, causing considerable damage. On March 26th, the tank was recovered from the battlefield. For his heroism, Captain Belodub received the Order of Suvorov 3rd class. 

As of March 25th, the regiment lost 5 tanks irreparably, 2 were stuck in a swamp, 6 were under repairs, and 8 were functional. Later, the number of functional tanks increased to 11, and the difference was made up with 6 KV-1 tanks. Later, these Churchills took part in Operation Brusilov, which began on July 22nd, 1943. Overall, the British tanks were evaluated positively, and fought well alongside infantry. However, the 2-pounder was much weaker than the KV-1's gun. The regiment received KV-1 tanks in place of Churchills in December of 1943, and later IS-2 tanks.

Churchill III from the 48th Guards Heavy Tank Regiment entering Kiev.

Churchills held out the longest in the 49th Guards Heavy Tank Regiment. This regiment arrived at Obukhovo station on March 14th, but entered battle much later. It remained in reserve throughout 1943, and only saw battle on January 15th, 1944. The 49th Guards Heavy Tank Regiment took part in the final lifting of the blockade on Leningrad. To make up for its losses, the regiment received 23 BT-5 and 3 BT-7 tanks. This strange situation continued until mid-February, when the regiment had 13 Churchills and 16 BT tanks left. After that, the regiment was sent to Tula to receive IS-2 tanks.

Combat actions of the 36th Guards Heavy Tank Regiment at Prokhorovka.

A new wave of Churchill regiments began forming in the spring of 1943. This was connected with receiving over 150 tanks through the Arctic convoys. Tanks of this type were sent to the 10th, 15th, 34th, and 36th Guards Heavy Tank Regiments. In addition, the tanks of the 47th and 48th Heavy Tank Regiments were refreshed. Two of the above regiments (36th and 48th) fought at Kursk. The 48th Guards Heavy Tank Regiment entered battle on July 6th, 1943, losing 8 tanks on the first day (one was knocked out by German aircraft), claiming 23 tanks and 13 SPGs knocked out. The regiment retreated to Prokhorovka on the next day, acting alongside the 21st Tank Brigade. 7 more tanks were lost during the retreat, but the regiment claimed 5 enemy tanks and 7 SPGs. Over the next several days, the 6 remaining Churchills were transferred to the 21st Tank Brigade. The regiment received Churchill tanks once more on September 9th, 1943, which they used to liberate Kiev.

The 36th Guards Tank Regiment had a different experience. The regiment moved out to its positions on July 9th. 5 tanks broke down on the way. The regiment took up defensive positions to the north of Prokhorovka. The regiment took an active part in the battle on July 12th. The commander was wounded by enemy aircraft on the morning of the battle. The regiment began the fight with 15 functional tanks. 7 burned up and 4 were knocked out on July 12th. The regiment claimed 6 German tanks, two of which were Tigers. The regiment had 10 Churchills left after the battles of July-August. On August 23rd, they were sent off for repairs, and 13 SU-152 and KV-1S were accepted in exchange. The regiment received Churchills once again in late December. Some of them were the same tanks they used earlier. The regiment received 14 Churchills in total, which it used to fight at Pskov until early April of 1944. In June, the regiment was re-equipped with IS-2 tanks.

Churchill IV from the 260th Guards Heavy Tank Regiment in Wyborg.

Intensive use of Churchill tanks left its mark. By January 1st, 1944, 160 tanks were lost irreparably. 27 more were lost by June 1st. Of 66 remaining tanks, 31 were issued. They were mostly concentrated on the Leningrad Front, where they were actively used. For example, the 260th Guards Heavy Tank Regiment received 6 Churchill tanks, which were used during the fighting for Wyborg. The 82nd Tank Regiment, which had 10 Churchill tanks and 11 KV-1S tanks, participated in the liberation of Tallinn in September of 1944. 63 tanks of this type remained by January 1st, 1945. 9 of them were lost before the end of the war. By June 1st, the Red Army had 54 leftover Churchills, only 3 of which were in any active unit.

Shermans in the Mud

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Few people interested in WWII armoured warfare haven't seen this video depicting Swedish trials of a Sherman, a Churchill, and a Panther in difficult off-road conditions. Many people, after having seen this video, readily claim that the Sherman had inferior off-road mobility to the Panther. Certainly, it's hard to argue with the video, but there is a caveat. There were many different kinds of Shermans, and the video only tests one of them. I thought I'd take a look at some trials performed by the Western Allies in Europe to see if they arrived at the same results.

Very similar trials were conducted by the British, described in Mediterranean Area AFV Technical Report #27, Appendix D. The test consisted of the following conditions:

"
  1. Raised road. This involved the tanks having to climb 3 to 4 feet onto a road and descending a similar bank on the other side of the road into a ditch filled with water to an approximate depth of 2 feet. The ditch varied from 9 to 14 feet in width at the bottom. The far side of the ditch involved a climb of approximately 3 feet with a soft bank.
  2. The tanks then had to cross a stretch of grass field to a strip of plough, approximately 80 yards broad, half of which had previously been watered for three successive days. This represented the condition of a normal ploughed field encountered after rain.
  3. The soil was everywhere the same, classified as clay with a small proportion of silt and fine sand, and when wet of low supporting power."
Seven different configurations of Sherman tanks as well as a Churchill and a Panther participated in the test. Let's see how they did.

Tank
Tracks
Road
Ditch
Plough
Sherman (diesel)
Steel chevron
Success
Fail
Not attempted
Sherman (diesel)
Ditto with end connectors
Success
Success
Failed after 20 yards
Sherman (diesel)
Rubber tracks and platypus grousers
Success
Success (easy)
Success in second gear (easy)
Sherman (diesel)
Steel tracks with MWEE grousers
Success
Success (easy)
Success in second gear (easy)
Sherman (diesel)
Steel tracks with rat grousers
Success
Success (easy)
Success in first gear (easy)
Sherman (diesel)
Rubber track alternating standard and platypus grousers
Success
Success (easy)
Success in second and first gears (easy)
Sherman (radial petrol)
Rubber tracks
Success
Fail
Not attempted
Sherman (radial petrol)
Rubber tracks and platypus grousers
Success
Success (easy)
Success in second and first gears (easy)
Churchill IV
Standard
Success
Success
1st attempt stuck 5 yards from the end, reversed out. 2nd attempt crossed very slowly in first gear.
Panther
Standard
Success
Success
Failed after proceeding very slowly after considerable track slip.

The Panther does do better than at least some kind of Sherman. The basic diesel (M4A2) and radial petrol (M4A1) Shermans failed the ditch test, which the Panther succeeded in. However, the Sherman with extended end connectors performed as well as the Panther did, and all other Shermans were superior to the Panther. The kind of tank shown in the video, a Sherman Vc, was much heavier than any of these tanks, and had basic steel chevron tracks, so its performance was not surprising. 

The trials were followed by a race through the same terrain, but backwards. Unfortunately, the Panther could not participate, as its gearbox had broken. The winner of this race was tank #3 with platypus grousers, that went through the whole race in second gear and was even able to switch into third for some sections. Tank #6 (alternating grousers) came second, also able to use third gear a little bit. 

This sort of result isn't a fluke. Other trials show the same thing. For instance, trials at the Fighting Vehicles Proving Establishment in Surrey, which compared another heap of combinations of Shermans and tracks, comes to the following conclusions:
"Panther

Of the heavy vehicles, Panther had better flotation characteristics than the most successful combinations of special tracks tested. 

On traction, the results were substantially inferior to those of the Churchill, and only slightly better than those for the Sherman with standard steel chevrons."

Sources:
  • LAC RG 24 C 2 (Canadian Military Headquarters in London) 55/534/9/2 (AFV Technical Reports ME)
  • Fighting Vehicle Proving Establishment Report #FT1553/2 Comparative Trials of Somerset Coastal Sites with Various AFV Tracks in Soft Ground Conditions

45 mm Tank Destroyer

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"Attachment #3 to GOKO decree #2429ss
October 19th, 1942

Tactical-technical characteristics for a 45 mm SPG

1. Purpose of the SPG

The 45 mm SPG is designed to function as a weapon in tank destroyer regiments and in anti-tank batteries of moto-mechanized units to combat enemy infantry and tanks.
2. Requirements for the SPG armament

The tank destroyer SPG will use the oscillating part of the 45 mm M-42 model 1942 anti-tank gun. The weapon must satisfy the following requirements:
  1. Muzzle velocity of 870 m/s with a 1.4 kg armour piercing shell.
  2. Capability of firing armour piercing, high explosive, and subcaliber ammunition.
  3. Practical rate of fire of at least 15 RPM in direct fire.
  4. Gun elevation of at least +15 degrees.
  5. Gun depression of at least -5 degrees.
  6. Horizontal arc of at least 30 degrees (15 degrees to each side).
  7. Horizontal and vertical aiming must be achieved at a speed of at least 1.5 degrees per second.
  8. The height of the bore axis can be at most 1600 mm.
  9. The gun must use the AZP sight.
  10. The gun is serviced by a crew of 3 (including the driver). The fighting compartment must contain folding or removable seats for two crewmen.
  11. The gun must be reliably fixed in the vertical and horizontal planes during travel.
  12. The gun must be convenient to load at any elevation or traverse angle.
  13. The SPG must be armed with two PPSh submachineguns. 
  14. The SPG must carry 90 rounds for the 45 mm cannon and 1000 rounds for the machineguns. The ammunition racks must be reliable and keep the rounds safe in motion. It must be easy to extract the rounds from the rack."

Moonlighting

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"From March 26th to April 1st, 1942

There is no change in the [123rd] brigade's location. Training continues. Tank companies are working on exercise 4 of the KOP-38 manual.

Between March 26th and March 28th, the brigade Staff, commanders, and company commissars participated in communications, chemical, and small arms training: exercise 2 of the KOP-38 with personal weapons.

Sniper pairs continue their destruction of enemy personnel. During the period of March 26th, 27th, 28th, and 29th they destroyed 28 fascists. Our losses: death of sniper Red Armyman V.D. Lugovets.

In total, 315 fascists and one horse were destroyed during the month of March.
The best snipers in the brigade destroyed the following amounts of fascist occupants:
  1. Sniper-Red Armyman A.Z. Melamed: 41 fascists
  2. Sniper-Red Armyman I.T. Ryzhkov: 34
  3. Sniper-Red Armyman M.T. Tumanov: 22
  4. Sniper-Red Armyman M.I. Shkadenko: 19
  5. Sniper-Red Armyman N.K. Kozakov: 18
  6. Sniper-Red Armyman N.A. Galkin: 15
  7. Sniper-Red Armyman V.V. Kostin: 10
  8. Sniper-Red Armyman I.K. Pavlik: 9
  9. Sniper-Red Armyman I.Ya. Akrizkov: 9
  10. Sniper-Red Armyman A.M. Tkachenko: 8
  11. Sniper-Red Armyman V.F. Averyanov: 8
  12. Sniper-Red Armyman M.V. Serbin: 8
  13. Sniper-Red Armyman N.G. Makeev: 7
  14. Sniper-Red Armyman P.R. Vasilyev: 7
  15. Sniper-Red Armyman V.G. Grigoryev
  16. Sniper-Red Armyman I.A. Vasilyev: 6
  17. Sniper-Red Armyman G.A. Sinkov: 6
  18. Sniper-Sergeant M.G. Makarov: 6
  19. Sniper-Corporal V.D. Lugovets: 6
  20. Sniper-Red Armyman V.I. Dikov: 5
  21. Sniper-Red Armyman S.M. Maksimov: 5
  22. Sniper-Red Armyman I.F. Nemchenko: 5
  23. Sniper-Corporal N.D. Starovoylov: 4
  24. Sniper-Red Armyman V.A. Hobotov: 4
  25. Sniper-Red Armyman A.N. Savinov: 4
  26. Sniper-Red Armyman A.M. Mikhailov: 4
  27. Sniper-Junior Sergeant D.I. Veretennikov: 4
  28. Sniper-Red Armyman M.S. Shurov: 4"

Intermediate Cartridge

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"Act
December 25th, 1941
Chebarkul, Chelyabinsk oblast

We, the undersigned, Chief of the 1st Department of the NIPSVO, Military Engineer 1st Class R.A. Kulinich, Chief of the Design Department, Intendant 1st Class V.F. Kuzmischev, and an engineer of the Design Department, Military Technician 1st Class Yermolenko, compose this act to certify that the NIPSVO Design Department worked  on a 5.6 mm semiautomatic rifle according to GAU project #380.
An overall design for a new 5.6 mm semiautomatic rifle was designed, and experimental work was performed on a model 1941 semiautomatic rifle by replacing the barrel and gas piston.

Experimental trials showed that the receiver of the model 1941 semiautomatic rifle was unsatisfactory in toughness and became bent in the middle.

A design study established that it was impossible to produce a weapon that falls under the required weight of 3.6 kg with such a powerful round. This round can only offer slight advantages over the existing round when fired at close range. Further work on this type of weapon was deemed senseless.

Settle the accounts for order #751.

[Signatures]"


An Alternative from Gorky

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The history of Soviet light SPGs is inseparable from the city of Gorky, modern day Nizhniy Novgorod. Guns installed on Soviet light SPGs were developed and built here. The ZIS-30, the first Soviet wartime light SPG, was also created here. Gorky housed the main manufacturing base of T-60 and T-70 tanks, which were used as SPG chassis. It's not surprising that the design bureau of the Molotov GAZ factory eventually switched to building SPGs. The GAZ-71 and GAZ-72 SPGs might have become the main light SPGs of the Red Army.

Mandatory competition

Work on SPGs was not considered high priority at the Molotov GAZ. The factory had enough work in its primary field. Production shifted from the T-60 to the superior T-70 in the spring of 1942. This was not the first vehicle created in Gorky: the TM (Molotov Tank) amphibious reconnaissance tank was designed here in 1936 under the direction of V.V. Danilov. This was a very unusual vehicle, equipped with a pair of GAZ AA engines. The TM did not progress past a prototype, but the GAZ-70, aka T-70, was a real ace in the sleeve of the Soviet tank industry and the Red Army. Thanks to this tank, the vacuum left by the cancellation of the T-50 could finally be filled.

Of course, the T-50 was superior to the T-70, but you have to fight with the army you have. The T-50 never made it to mass production, but the T-70 was built to match the capabilities of wartime industry. It's not surprising that this tank was the second most numerous tank to be produced during the war, after the T-34. The chassis of the T-70 was also perfect for the development of SPGs.

Tactical-technical requirements for a 45 mm tank destroyer. This vehicle was to be developed by GAZ on the chassis of the T-70 tank.

The center for medium SPG development in the first half of 1942 was in Sverdlovsk. Factory #37 was evacuated here in late 1941. Department #22, reborn on its new grounds, worked on the creation of light SPGs in addition to their work on the T-30 and T-60. The design bureau worked closely with S.A. Ginzburg, putting his idea of a "universal chassis" on the T-60 platform into fruition. This was the start of the development of the SU-31 and SU-32 SPGs.

One of these vehicles could have gone into production, but fate intervened. GKO decree #2120 "On the organization of T-34 production at Uralmash and factory #37" was published on July 28th, 1942. According to this decree, factory #37 was included into the Ural Heavy Machinebuilding Factory (UZTM), and production of light tanks ceased. Work on light SPGs in Sverdlovsk also stopped. Materials on the SU-31 and SU-32 were passed onto factory #38 in Kirov, where Ginzburg began working closely with the factory design bureau under the direction of M.N. Schukin.

GKO decree #2429 "On the production of experimental SPGs", the starting point for the development of the SU-11, SU-12, SU-71, and SU-72. The SPAAG did not make it into the initial draft, and was written in by Stalin personally.

Trials of the SU-31 and SU-32 continued until September of 1942. As a result, the choice was made in favour of the "31" chassis, with a parallel placement of GAZ-202 engines. This layout was used at factory #38. On the other hand, the GAU and GABTU decided to have a backup plan. Serious delays took place in every light SPG development program, and an idea came up to enlist the help of the Molotov GAZ design bureau. Deputy Chief Designer N.A. Astrov became the head of this project. At the time, the bureau was working on the modernization of the T-70 tank, but did not refuse this urgent order. Work on yet another SPG began. In case Ginzburg and factory #38 failed, it would have become the long-awaited SU-76.

Another way

The tactical-technical requirements for new SPGs were completed by October 16th, 1942. The brass decided to not reinvent the wheel and give largely the same requirements as were given for the SU-31 and SU-32. Even the layout was the same as for the Sverdlovsk SPGs. For instance, the "76 mm assault SPG" was based on the chassis that was built with T-70 components. This meant that it used the GAZ-203 dual engine. This seems interesting, as the GAU rejected the same setup on the SU-32, since it overheated. GAU Chief, Colonel-General N.D. Yakovlev and the Deputy of the People's Commissar of Defense, Colonel-General N.N. Voronov knew about these trials, but signed the requirements anyway.

The 57 mm IS-1 anti-tank gun was considered as an alternative to the ZIS-3. This gun was a reworked version of the ZIS-2 gun, designed at factory #92 under Grabin's direction in the summer-fall of 1942. The same gun would be used on the ZIS-41 halftrack SPG. The requirements stated that a ZIS-3 armed SPG had to carry 60 rounds of ammunition. The weight limit was 10 tons, and the maximum height of the vehicle during travel was 2 meters. The calculated top speed was 45 kph, and the range was 200-250 km.

Cutaway diagram of the GAZ-71. As you can see, the layout of the vehicle is unusual.

The chassis had to allow for a SPAAG to be developed on the same base. However, the requirements for a 37 mm SPAAG were filed separately. This vehicle was nearly identical in its layout to the SU-31, including the parallel placement of GAZ-202 engines. The requirements for the chassis were the same as for the 76 mm assault SPG.

A third vehicle on the chassis of the T-70 appeared. On the same day, Voronov and Yakovlev approved a "45 mm SPG". This vehicle would use the 45 mm M-42 gun, recently accepted for service by the Red Army. The gun would be installed on the T-70 tank. The whole tank, not just the chassis.

The chassis looked even more unusual from above.

Stalin signed GKO decree #2429 on October 19th, 1942, titled "On the production of experimental SPGs". The SPAAG was not included into the original draft, but added later.

"2. The People's Commissar of Tank Production (comrade Zaltsmann) and People's Commissar of Medium Machinebuilding (comrade Akopov) must immediately create prototypes of 76 mm SPGs on the T-70 chassis, delivering them for proving grounds trials by November 15th of this year.
3. The People's Commissar of Medium Machinebuilding (comrade Akopov) must immediately build a prototype of an SPG with a 45 mm gun on the T-70 tank chassis, delivering it for proving grounds trials by November 20th of this year.
4. The People's Commissar of Tank Production (comrade Zaltsmann) and People's Commissar of Medium Machinebuilding (comrade Akopov) must build and deliver for trials samples of SPAAGs with 37 mm guns on the T-70 chassis by December 1st of this year."

All three SPGs were to be designed at the Molotov GAZ factory. The 76 mm assault SPG was indexed GAZ-71. The lead engineer on this project was V.S. Solovyev. The SPAAG received the index GAZ-72, with A.S. Malakov as the lead engineer. Finally, the 45 mm SPG on the T-70 chassis received the index GAZ-73. Major P.F. Solomonov, who oversaw work on SPGs since the fall of 1941, curated the work from GAU's side. According to plans, the GAZ-71 was to be done by November 15th, the GAZ-73 by November 20th, and the GAZ-72 by December 1st, 1942.

Diagram of the transmission of the GAZ-71 and GAZ-72

The Molotov GAZ design bureau treated the requirements rather frivolously, as did the design bureau of factory #38. Primarily, this had to do with the layout of the SPGs. Neither Kirov nor Gorky intended to design a vehicle with GAZ-203 engines. This is a reasonable decision, since, as mentioned above, this engine overheated on the SU-32. It's not surprising that GAZ-202 engines placed in parallel were preferred.

The life of the GAZ-73 project was brief. No imaged of this vehicle remain, but it would generally be similar to the IS-10 SPG, designed at factory #92. GAZ quickly understood that such a vehicle is senseless. Work did not progress past the design stage. In order to place the weapon properly, the vehicle would have to be 20 cm taller. The fighting compartment was still small, and the mobility of fire and rate of fire would be low. Work on the GAZ-73 took a different path by the end of November of 1942: now it was being built on the GAZ-71 chassis. Instead of turbocharged GAZ engines, it would use ZIS-16 engines. The last mention of this vehicle is dated November 29th, 1942. No work was performed after that.

GAZ-71 at the factory, December 1942.

The GAZ-71, also called SU-71 in correspondence, was doing much better. It was not build by November 15th, as GKO decree #2429 required. However, it was built by November 28th, and was being prepared for factory trials. The SPG was rather original. Formally, the SU-71 was based on the T-70B chassis, but many changes were introduced. The drive sprockets and final drives were moved from the front to the rear. The idlers migrated to the front, and also lost their rubber rims. The GAZ MM gearbox and friction clutches migrated under floor of the fighting compartment, on the right side. The fuel tanks were on the left side.

Unlike the SU-31, the gearboxes were not placed separately along the sides of the hull, but placed near each other. The friction clutches were nearby too. The main clutches were positioned in such a way that it was possible to turn them on and off individually, making it possible to drive with only one engine. The engines remained in the front of the SU-71, but they were placed next to each other, shifted to the right. The driver's station was moved to the left.

The same vehicle from the front.

The hull of the SU-71 was also very original. The front was built from two, not three parts. The lower part had hatches to access the engine starters, and the driver's hatch and engine access hatch were on top. The gun mount was also different. only the oscillating part of the ZIS-3 and its upper mount were taken. The upper mount was installed in a hole on top of the front plate. This kind of design was envisioned at factory #37, but was never implemented. This solution made the fighting compartment roomier than on the SU-32. The recoil mechanisms were covered by a complex plate.

The fighting compartment.

The upper sides of the hull and casemate were made in one piece, and were sloped. This gave the SU-71 a roomy fighting compartment. However, the floor was elevated, since the transmission and fuel tanks were underneath. The fighting compartment was accessed through a large two-piece hatch in the upper rear plate of the casemate. The radio was placed to the left of the compartment, but the commander's station and his periscopic observation device were to the right. The ammunition was housed underneath the gun (15 rounds), and in crates along the sides of the fighting compartment (three creates to the right and one to the left, their lids acting as seats during travel). Eight more rounds were held on the rear wall of the compartment. Since the SU-71 had no fenders, most of the tools were kept inside the fighting compartment.

Original, but unreliable

The issues that were discovered during the development of the GAZ-73 were the first, but not the last, misfortune encountered by the Molotov GAZ design bureau. As mentioned above, the SU-71 was being prepared for factory trials on November 28th. Meanwhile, factory #38 had not only already designed its own vehicle, indexed SU-12, but built it, and performed factory trials, which ended on November 27th. It was scheduled to be sent to the Gorohovets proving grounds (ANIOP) for trials on November 30th. Work in Gorky was moving slower, which is why their SPG already fell out of favour by December. GKO decree #2559 "On the organization of SPGs at the Uralmash factory and factory #38" was published on December 2nd, 1942. The Gorky SPG lost even before the comparative trials began.

Gun at maximum elevation.

Despite the decision of the State Committee of Defense regarding SU-12 production, comparative trials of the SU-12 and SU-71 were still proceeding as planned. The SU-12 arrived at the Gorohovets ANIOP on December 5th. By that point, the SPG had driven for 150 km.

As for the SU-71, its delivery was behind schedule. A member of the trials commission, Major Solomonov, was sent to the GAZ on December 3rd. A deadline for the reception of the SU-71 was set in the ensuing negotiations with the head of the commission, Lieutenant-General of Artillery V.G. Tikhonov in attendance: December 6th. The vehicle did not arrive in time once again, and only a second visit by Tikhonov ensured that the SPG was sent to the proving grounds. However, the SPG was turned back due to a defect in the cooling system. As a result, the SU-71 only reached the proving grounds by December 9th. After the factory trials program was completed, it returned to the factory on the next day.

The crew working in the fighting compartment.

The SU-71 returned to trials only on December 15th. The head of the GAZ design bureau, V.A. Dedkov,  and Kulikov, the military representative, arrived with it. The SU-71 fired 64 shots and travelled for 350 km by then. Proper trials of the suspension were never performed, as the vehicle was pursued by technical issues. As a result, the SU-71 only went through gunnery trials. A further 235 shots were fired to test the reliability of the gun mount.

GAZ-71 from the rear.

Technical breakdowns notwithstanding, the SPG was not entirely satisfactory from the point of view of requirements. Instead of 10 tons, like the requirements stated, the SPG weighed 11.75. This kind of overloading resulted in engine trouble and other defects. The vehicle was 15 cm taller than required, and the elevation and traverse angles were insufficient. It was not possible to establish the top speed due to technical issues, but there is a sneaking suspicion that it would not have been 45 kph. One of the few positives was the gun mounting method. The overall verdict was not unexpected: the SPG cannot be recommended for service, and attempts to improve the design would be senseless.

GAZ-72 SPAAG, created on the GAZ-71 chassis.

The GAZ-72 SPAAG was lost in the troubles of the GAZ-71/SU-71. Even its exterior is practically unknown. This is because work on the GAZ-72 took even longer. The hull was not ready by November 28th. The factory management optimistically estimated that it would be ready by December 6th, but that was not the case. Overall, the design of the vehicle was the same as the GAZ-71, but the rear housed the oscillating part of the 61-K 37 mm AA autocannon. It differed little from the one used on the SU-31. The rear of the vehicle had to be widened to fit the gun.

The poor performance of the GAZ-71 meant that the SPAAG was never even tested.

After the SU-71 was rejected, interest in the GAZ-72 waned. Since these vehicles shared a chassis, it was obvious that similar problems would be encountered during trials. There were also additional issues with servicing the transmission, as the gun would have to be removed. It is not surprising that the GAZ-72 never made it past factory work.

However, this was not the end of light SPGs at the Molotov GAZ. The GAZ-74 SPG entered trials in May of 1943. This vehicle deserves a separate article.

SU-152 in Combat

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"1836th Heavy Self Propelled Artillery Regiment

The 1838th Guards Heavy Self Propelled Artillery Regiment participated in offensive and defensive combat.

In offensive combat, the regiment fought among the tanks and behind them, destroying Tiger tanks and Ferdinand SPGs in counterattacks and ambushes, as well as enemy fortifications and dugouts.

In defensive combat, the regiment fought from ambushes, by the battery, positioned in locations of likely enemy tank attacks. Ambushes and maneuvers ensured that enemy tanks and SPGs were destroyed while SU-152s remained invulnerable.

The armoured 152 mm gun-howitzer on the KV chassis destroys enemy heavy tanks and SPGs that are difficult to destroy with tanks with its powerful fire. During these battles, it was established that a 152 mm HE shell knocks off the turret from 1200-1500 meters, and, if it hits the hull, destroys the tank's armour. The 152 mm shell destroys any field fortification or dugout.

The regiment began fighting at the Bukrin foothold with 12 SU-152s and one KV-1S. In almost all cases, the regiment was parcelled out by batteries. Batteries were used to reinforce tank brigades in the main direction of the offensive. The regiment's main objectives were: combat against heavy tanks, heavy SPGs, and guns concealed in fortifications.

On October 12th, 1943, during the offensive at Lesser Bukrin, Lieutenant Grinchenko's battery, in cooperation with the 241st Rifle Division and 229th Tank Regiment of the 27th Army, met an enemy counterattack coming from Lesser Bukrin. Lieutenant Grinchenko decided to put his battery ahead of the tanks and deflect this attack. As a result of decisive action, the battery deflected the counterattack, destroying two PzIV tanks and one Ferdinand type SPG, 4 trucks with cargo, and up to 150 soldiers and officers. Grinchenko's battery helped carry out the order to capture Lesser Bukrin.

On October 21st, 1943, Lieutenant Kolotilo's SPG was placed in ambush near height 194.8. Having picked out a convenient location for direct fire and organized thorough observation, he detected two Ferdinand type SPGs that were firing on our tanks, which were advancing towards Hodorov, from a position north-east of Romashki. When the enemy tanks began to change positions, Guards Lieutenant Kolotilo opened fire at 1200 meters, knocked out one Ferdinand type SPG and one Tiger tank.

In the same region, Guards Lieutenant Yavorskiy's SPG destroyed three trucks with cargo, one warehouse, and up to 50 soldiers and officers."


As we know, the "Ferdinand type SPG" could have been anything, but Tigers are easy to check. 8./SS-Panzer-Regiment 2 just arrived at Pii (some 11 km away from Romashki). The company commander was wounded in "mid-October", and the records become very sparse after that, but the fact that the company was down to 3 operational tanks from a total of 16 (out of an authorized strength of 27), it's quite possible that a few of them ran into Kolotilo and his fellow SPGs.

Aircraft Costs

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"Prime cost of important products of the People's Commissariat of Aircraft Production

Item
Factory
Prime in thousands cost during
% change in May
June 1941
1st quarter 1942
May 1942
Compared to June 1941
Compared to 1st quarter 1942
Aircraft






PE-2
#22
455.9
406.3
-
-
-
PE-2
#39
577.1
524.0
462.6
-19.8
-12.0
IL-4
#126
1148.0
479.0
409.4
-64.4
-14.5
IL-2
#18
308.5
214.5
208.0
-32.6
-3.0
PS-84
#84
569.1
574.3
531.0
-6.5
-7.5
LAGG-3
#21
265.5
154.3
118.9
-55.0
-23.9
YaK-1
#292
188.7
112.0
93.8
-50.5
-16.2
UT-2
#47
34.5
40.0
40.8
+9.0
+1.0
U-2
#387
29.6
26.9
23.2
-21.8
-14.0
Engines






M105R
#16
71.7
77.3
-
-
-
M82
#19
157.7
82.0
73.8
-53.2
-10.0
M62IR
#19
56.8
45.0
44.9
-21.0
-0.2
AM38
#24
60.5
87.0
54.1
-10.5
-37.8
M105P
#26
43.4
67.7
51.0
+9.0
-24.4
M88
#29
52.2
53.5
49.5
-5.2
-7.5
M11
#154
11.1
11.0
9.9
-11.0
-10.0
"

Five Years of Blogging

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In my update a year ago, I promised something big by my fifth blogging anniversary. I'm happy to report on not just one, but two notable milestones!

The first, and probably most significant, is moving from online to paper. My translations have been published before, but this year saw the release of my first completely original work being printed. In addition to that, I started writing articles for the Russian military history website Warspot, which many of you will recognize as the source of many translations on this blog. So far I'm writing at a rate of about one article per month, but that might increase in the future. Articles about British and American evaluations of German armour seem to be most popular so far, with an analysis of the King Tiger sitting at nearly 20,000 views, the Panther at over 12,000 views, and the Tiger at nearly 10,000. Articles on Sherman tanks are proving to be quite popular as well, with the Sherman V and M4A1(76)W sitting at over 7,000 each, despite being significantly more recent. Canadian subject matter is proving to be less popular, with the Valentine VII falling short of 7,000 views and the Ram at under 5,000.

Unfortunately for my English speaking readers, all of these articles are in Russian. Currently, The Armor Journal has first dibs on the English versions, but the articles will be posted here some time after they are published. 

Another new feature (or so old it's new again) is my Twitter, which is slowly but surely gaining followers at an average rate of one per day (give or take). 

Now, for the stats you're used to. I'm up to 1687 published articles (up from 1381), and 3,039,948 views (up from 2,161,945). Google Analytics congratulated me on a record high number of unique users for the month of January. It's great to see how my readership is growing!

The demographics haven't changed much. The US preserves its lead, but the UK broke away from Germany, setting second and third place pretty steadily. Russia, Canada, Poland, and France keep their positions. Finland has a fair lead on Austria for eighth place, and the tenth place now belongs to Spain instead of South Korea. 

Aside from that, a few more book citations, a handful of new archive sources, and an upcoming appearance in a podcast, so if you just can't get enough of Tank Archives, there's plenty of content to look forward to. Thank you for five wonderful years!

MKb 42(H) First Appearance

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I wrote about Sturmgewehr intel before, but here's an even earlier appearance:


"Main data:
  1. Automatic fire provided by gunpowder gases passing through the gas opening.
  2. The barrel locks via the bolt tilting.
  3. Uses a special shortened round, similar to the rifle ones.
  4. Range: up to 800 meters.
  5. Has a selector for automatic and single-shot fire.
  6. Equipped with a bayonet for hand to hand combat."
The intelligence brief reads:

"Carbine-machinegun MK-42

The model 1942 7.92 mm carbine-machinegun with a 30-36 round special magazine (uses shortened 7.92 mm rifle bullets) is carried on a strap affixed to the stock and across from the bayonet lug. It's easy to disassemble. Judging by the design, the magazine is also used as a foregrip (there is no sign of an attachable bipod). Externally, the gun is composed of the following parts:
  1. Barrel
  2. Front sight with safety
  3. Gas piston pipe
  4. Barrel shroud
  5. Rear sight
  6. Bolt
  7. Magazine
  8. Base with pistol grip and trigger guard
  9. Stock with an opening for accessories
The striker mechanism of the machinegun-carbine is composed of the following parts:
  1. Gas piston
  2. Operating slide
  3. Bolt base
  4. Bolt (there is a safety on the bolt plunger and a handle for pulling it back)
The bolt is composed of the following parts:
  1. Bolt case
  2. Extractor
  3. Firing pin
Judging by the design of the cooling system, it can be expected that the rate of fire and automatic qualities of the machinegun-carbine are not high."

Via biserg-1977

KV-1S: From Temporary to Permanent

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State Committee of Defense decree #1878 "On the improvement of KV tanks" was signed on July 5th, 1943. This was the starting point for the creation of a lighter variant of the KV, named KV-1S. Two prototypes were built by July 27th, and mass production began in Chelyabinsk by late August. The KV-1S was not as much of a legend as the KV-1, but this was the tank that defeated the Germans at Stalingrad and Kursk. Its creation and production was, in many ways, a necessary evil, but the KV-1S remained in production for a year, and remained on the front lines until 1944. This article covers its production and use in combat.
Road Wheel Switcharoo

As luck would have it, the KV-1S, like its cousin the KV-13, was born during a difficult time for its country and the Chelyabinsk Kirov Factory. Due to an order to begin building T-34 tanks at ChKZ, and then at the Ural Heavy Machinebuilding Factory (UZTM), production of the KV-1S was incredibly difficult. UZTM stopped supplying the Kirov factory with hulls and turrets after it began T-34 production. Because of this, Cheylabinsk was forced to produce 70 KV-1S tanks with KV-1 hulls. Difficulties with hulls and turrets had many impacts on the tank's production.

KV-1S tanks produced in September and October looked like this.

There were issues with other components. Issues with road wheels were some of the first to crop up. The KV-1 used road wheels made according to blueprint 33-803, which were in production since February of 1942. Each of these wheels weighed 170 kg. SKB-2 designed lighter wheels for the KV-1S. Road wheels with blueprint number 33-65 were installed on the first two KV-1S prototypes, as well as on tanks from the pilot batch. The designers reduced the mass of each road wheel to 135 kg, which saved 420 kg from the tank's overall mass.

This tank has 833-16 road wheels. As you can see, it has neither handrails nor additional fuel tanks.

The problem with 33-65 road wheels was that they were ill-suited for mass production. They were not good from a casting technology point of view. The casting plant tried to master them in July-August of 1942, but could not pull it off. As a result, ChKZ was forced to use old 33-803 road wheels on August and some September production tanks.

Another road wheel was developed in the second half of August on the steel casters' request: 833-16. It was even lighter than 33-65, weighing only 125 kg. The design was similar to the KV-13's road wheels, which was designed in the summer of 1942. 833-16 road wheels were successfully tested in comparative trials using vertical drop machines and was introduced into production starting on August 31st. There was some time before its production could be mastered, and some KV-1S built in September received old KV-1 wheels.

The KV-1S used 608 mm wide tracks until November 1st, 1942.

The mass production KV-1S had more differences from the prototypes than just the wheels. For an unknown reason, production tanks lost handrails on their hulls and turrets. A number of changes was introduced in September-October. The cooling system was slightly altered in September, and tanks were equipped with lighter cranks and swing arms starting on the 30th. An improved ammo rack layout was installed after October 9th, which increased the amount of ammunition carried to 114 rounds for the cannon and 49 magazines for the DT. Installation of additional fuel and oil tanks began on the same day. These tanks were supposed to go onto the first KV-1S tanks, but there were various delays in their introduction.

The turret contains a casting numbers. These numbers, later somewhat different looking, became the calling card of factory #200.

Another significant change was the appearance of a new road wheel, indexed 33-67. According to an official list of changes, it was introduced on November 5th, 1942, and was installed on vehicles after tank #210109. However, there is evidence showing that the transition happened much earlier, in October. This road wheel was a somewhat altered 833-16, which was officially considered an experimental design. Both types of road wheels were installed on tanks in parallel in October of 1942.

833-16 (right) and 33-67 road wheels on a KV-1S in Parfino.

A scandal broke out in regards to 33-67 road wheels in November of 1942. Large scale breakdowns were recorded. For instance, the 5th Guards Tank Regiment registered 164 breakdowns for November 10th and 11th. There were serious investigations at the factory. It turned out that the issue was not so much the design, but the quality of production.

The scandal took place during a time of significant issues with casting, which led to delays with supplies. The last tank from September's quota was accepted on October 2nd, the last tank from October's quota was built on November 6th and delivered on November 9th. Issues with hull supplies made their mark, which was especially noticeable in November and December of 1942. The last November tank was built on December 7th and delivered on December 15th. The last tank for December was built on January 10th and delivered on January 11th. This was the cost for starting T-34 production in Chelyabinsk.

KV-1S with serial number 30184, early February 1943 production. Tanks of this type looked like this starting with December of 1942.

Modernization of the design continued during the last two months of 1942. Tanks were equipped with 650 mm wide tracks starting with November 1st, and the hull handrails returned on the 28th. The commander's seat was also somewhat altered in November, and the swing arm mounts were attached by welding. Starting with November 25th (officially, December 2nd) a modernized road wheel with blueprint number 22-69 was introduced. This was the last step in switching around road wheels. On December 10th, the turret handrails were reintroduced. December became a pivotal month for the tank. The most serious visual changes happened during this month.

Waning interest

Due to a whole series of issues, the real volumes of KV-1S production were different from what was expected. 510 tanks were planned for the 4th quarter of 1942: 145 in October, 170 in November, 195 in December. In reality, 165 were accepted in October, 125 in November, and the same number in December. In total, 415 were accepted.

A big investigation took place regarding acceptance of the vehicles, triggered by a memo from the assistant military representative, Engineer-Captain P.N. Kotov. For context, there was a lot of tension between Kotov and Captain I.N. Skribtsov, the senior military representative at ChKZ. As a result of the investigation, Skribtsov was proven to be in the right, despite is strained relationship with Zaltsmann, the People's Commissar of Tank Production. This is based on Skribtsov's refusal to push tanks through the acceptance process retroactively in the fall of 1941. As for Engineer-Captain Kotov, his desire to be transferred out of ChKZ was unexpectedly granted. He was appointed as the assistant to the chief of the 6th department of the Main Directorate of Captured Armament, where he directed the parting out of captured vehicles.

Production of 33-69 road wheels, early 1943.

Issues with KV-1S road wheels continued into 1943. With a quota of 124 tanks, the factory only delivered 93 (from factory #92 reports). Seeing the issues that the factory faced, the quota for the next month was lowered to 62 vehicles. It was overfulfilled: 72 KV-1S tanks were delivered in February. With a quota of 60 tanks in March only 52 were built, but the factory also repaired 11 tanks, which allowed it to complete the requirement.

Blueprint of the reworked hull with a two-piece upper front plate. The first hints of this design were dated December 1942.

Difficulties with production did not mean that the design will not change. According to the approved list of changes for 1943, dated January 25th, 1943, the KV-1S was in for a whole series of changes. An altered variant of the front hull with an upper front plate composed of two pieces was developed in December of 1942. This made the production of this part easier, as it was previously made from one bent variable thickness plate. According to plans, the new component would undergo ballistic testing on February 15th. In practice, this test was postponed to the summer, and then it disappeared from plans completely.

Another change was the introduction of a new radio operator's hatch, which could be opened regardless of the position of the turret. A two-piece hatch was acceptable. This change was also never completed. The same goes for the decision to make 60 mm thick armour from high hardness plates. As a result, the tank changed minimally in January. Control rods were changed, as well as the cylindrical armoured cover of the radio antenna that was replaced with a triangular one.

KV-1S, April 1943 production.

The situation with later modernizations did not not change. The issue of visibility from the commander's cupola, for example, was pressing. It was planned that it would be replaced with a new cupola, designed based on the second variant of the KV-13 cupola, with an exit hatch on top. Two more variants of the cupola were designed. As a result, the experimental tank received a cupola that was developed on orders of the chief of the 6th department, Engineer-Major Pestov. This cupola was also supposed to be installed on the KV-1S tank, but this proposal did not make it past the planning stage.

The production of the turret from high hardness steel also did not go past experimental work, despite the fact that trials performed in March of 1943 proved this idea to be correct. The only change made to the turret in March was the introduction of lifting hooks in the sides and rear. Experiments with installing a fan and MK-IV or T-80 periscopes in the turret also ended with nothing.

However, there were some changes made. The 10T-7 periscopic sight was introduced on February 1st. Some changes were made to the radio in March, and splash protection was added to the hull roof in April.

The same tank from the rear. The lifting hooks are visible.

The laissez-faire approach to modernization was directly caused by the fact that the KV-1S was a tank with no future. Both the factory management and the NKTP considered the KV-13 (aka IS-1) to be higher priority. It was better protected, its turret was roomier, the gun mount was more comfortable, and the design had more potential for modernization. GKO decree #2943 published on February 24th, 1943, discussed not only the production of prototypes, but a pilot batch. The KV-1S was already dead and buried. The IS-1 was supposed to replace it in the spring of 1943. The issue was that the trials of the successor were mixed, to say the least.

The KV-1S owes its survival on the assembly line to the German Tiger. Trials in April of 1943 showed that the 76 mm F-34 gun can do little against the tank, even at point-blank range. The IS-1 had to be equipped with a new 85 mm gun. Analogous work was performed with the KV-1S, which will be discussed in another article. Clearly, this kind of work was not instant, and so the old KV-1S remained in production for the time being.

August 1943 production KV-1S. The triangular armour around the antenna port is visible.

Preparation for an IS-1 pilot batch had an impact on production of the KV-1S in April of 1943. Instead of 85 tanks, 50 were delivered, with the production of the hulls and turrets being the limiting factor. This is not surprising, as factory #200 was responsible for hulls of the pilot batch. In addition, ChKZ began producing SU-152 SPGs on the KV-1S chassis, which ate into the hull supplies. This shortcoming was compensated for in May: with a requirement of 50 tanks, ChKZ put out 75 new ones, plus 4 repairs. A similar leap was observed in the summer: 30 tanks were delivered in June despite a quota of 42, but 52 tanks were delivered in July compared to the quota of 38. One of these tanks was converted into the KV-85 (Object 238).

The last major changes were introduced into the KV-1S in July. Removable front fenders were added, the cap on the engine compartment access hatch was changed, and the exhaust pipe covers changed shape. 

Exhaust pipe covers changes shape starting with July of 1943.

The last 39 KV-1S tanks were produced in August of 1943. The saying "meet the new boss, same as the old boss" applies here. Since the new IS-1 (object 237, aka IS-85) would take time to enter production, production of the KV-85 began in August. This was in many ways the same old KV-1S. In total, 1086 KV-1S tanks were produced between August of 1942 and August of 1943, and 15 more tanks were refurbished at the factory.

A transitional heavy tank

The KV-1S was issued to units starting with September of 1942. The first unit to receive these vehicles was the 58th Tank Brigade. Tank brigades received mixed reinforcements in September. For instance, the 33rd Tank Brigade received KV-1 and KV-1S tanks from the "Potrebkooperatsiya" tank column. It's very likely that KV-1S tanks that arrived in these mixed shipments had KV-1 gearboxes. A number of these tanks were built in September. 

On Stalin's orders, Guards Tank Regiments began forming on October 8th. 4 of them (47th through 50th) were equipped with Churchill tanks. Another 17 had KV-1S tanks. They were formed according to TO&E #010/267, which authorized 21 tanks per regiment. The 21-tank regiment structure remained until the end of the war.

Delivery of tanks to the 33rd Tank Brigade, September 26th, 1942. A mix of KV-1 and KV-1S tanks can be seen.

Reports on the KV-1S from its users were mixed. The hurried production of the tanks resulted in various defects. Widespread breakdowns of road wheels were reported in November of 1942. There were complaints about the 8-speed gearbox, but not the design, rather the careless assembly. Overall, the low quality of production was directly connected with ChKZ's excessive workload. Of course, the army needed T-34s, but this kind of rapid organization came at a cost. Chelyabinsk T-34s also had a number of production defects, especially their tracks.

Knocked out KV-1S, Stalingrad Front.

The problems of the KV-1S were not only from production defects. Reports connected with design drawbacks started coming in around October 1942. The claims of test crews that the smaller turret of the KV-1S was not any less comfortable were not exceptionally accurate. Most complains were directed at the commander's station. The cupola was uncomfortable, and had a 30 meter dead zone in front. The placement of the periscopic sight in front of it was not a great idea, as it obstructed the view.

Later, when the KV-1S went into battle, another significant complaint cropped up. The lack of a hatch in the cupola reduced the speed at which the crew could leave the tank if it was knocked out. The rear machinegun was uncomfortable to use. The commander's back was pressed against it, and the gunner was forced to move forward when the commander was using it. This prevented him from firing the main gun.

KV-1S tank column, 6th Guards Tank Regiment, spring of 1943.

The optics were also a source of complaints. The TMFD sight was installed in such a way that the armoured cover partially obstructed the view. The complaints were made as early as November of 1942, but the sight was only replaced in March of 1943. Training and combat revealed an issue with the observation devices. The glass blocks ruptured often. Complains about periscopic devices that were installed too high up also came in.

A KV-1 hull penetrated by a Tiger's shell, April 1943. The shell was fired from 1.5 km away.

Design and production defects were inevitable due to the speed at which the KV-1S was put into production. Nevertheless, the tank's designers did not get a Stalin Prize for nothing. The debut of the KV-1S at Stalingrad proved that the idea of a lightened heavy tank was correct, even though it had to sacrifice some armour. High mobility in combat was an important quality. Despite the aforementioned defects, the KV-1S was more reliable than its predecessor. This tank could carry out long marches, which was important in the offensive operations of late 1942 and early 1943.

KV-1S destroyed at Kursk.

Let us focus on the armour separately. There is an opinion that reducing the armour of the well protected KV-1 was a mistake. However, recall that the development of German artillery did not stand still. German units began receiving artillery, tanks, and SPGs that could deal with the armour of the KV-1 in the spring of 1942. Additionally, the German Tiger tank made its debut on the battlefield in the winter of 1942/43. Its 88 mm gun could penetrate the hull of the KV-1 from 1.5 km. The Panther, whose 75 mm KwK L/70 had even higher penetrative capabilities, made its debut in July of 1943 at Kursk.

The thick armour of the KV-1 ceased to be a significant advantage in the face of rapidly developing anti-tank artillery. The mobility of the tank, on the other hand, left much to be desired. The more mobile and less blind KV-1S performed better on the battlefield than its predecessor.

KV-1S from the 260th Guards Heavy Tank Regiment, July 1944.

The decline of the KV-1S came in late 1943, when KV-85 and later IS-1 and IS-2 tanks were issued. Despite this, several units kept using these tanks until the fall of 1944, especially at the Leningrad Front. This was a very unusual "zoo", where one could see many tanks that were long gone from other battlefields of the Great Patriotic War, including BT-5 and T-26 tanks. KV-1S tanks arrived at the Leningrad Front in the summer of 1943. Here, they fought shoulder to shoulder with KV-1 tanks, some of which had 2.5-3 years of fighting behind them. The last time the KV-1S was used was in the fall of 1944 during the liberation of the Baltics.

A KV-1S converted into a prime mover.

Let us mention the prime movers built using KV-1S tanks separately. The first conversions of these tanks into ARVs is dated February 1944. Tank repair factory (BTRZ) #1 converted 6 tanks in this fashion. In parallel, BTRZ #6 began converting these tanks, producing 4 prime movers in February. Recovery tractors were a rarity in the Red Army, and production of the Voroshilivets ended in the fall of 1941. Both KV-1 and KV-1S tanks were converted into prime movers. Not too many of these tanks were produced. Repair factories #1 and #7 build a handful of such vehicles. Repair factory #6 built the most of these vehicles. For instance, 14 prime movers were delivered in July of 1944.

Sturer Emil: Collector's Item from Stalingrad

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Cases where prototypes that never saw mass production ended up on the battlefield are not uncommon. In the USSR, the T-100 and SMK were tested in combat during the Winter War. The T-29 and A-20 defended Moscow in the Great Patriotic War. There are similar examples for Germany. Two experimental SPGs, built on the chassis of the VK 30.01(H) heavy tank, which also never made it into production, ended up near Stalingrad in 1942. Unlike its ancestor, these vehicles not only took part in the fighting, but achieved impressive results. These tank destroyers are known as Sturer Emil.

Rejected chassis

The idea to build an SPG capable of defeating long term fortifications was born in the minds of German designers even before the war. In 1938, Krupp began working on an SPG armed with the 105 mm K18 gun. The vehicle used the PzIV as a chassis, and was created with a specific goal in mind: the defeat of long term fortifications. The vehicle was indexed Pz.Sfl.IVa. However, the Germans knew that the 10 cm K18 was a powerful weapon, but not powerful enough to deal with the toughest of targets. The idea of a heavier bunker buster was pitched in 1939.

12.8 cm Flakzwilling 40/2, the most commonly known variant of the Flak 40. These guns were used in the AA defenses of Berlin and Vienna.

Its armament was found fairly quickly. Work on the 128 mm Flak Gerat 40 was in progress, which was eventually adopted as the 12.8 cm Flak 40. The gun was designed at Rheinmetall Borsig, and a prototype was built there in 1937. The gun had exceptional characteristics, but was incredibly heavy. It weighed 12 tons in combat position.

Using the AA gun as a starting point, Rheinmetall Borsig designed a variant called 12.8 cm Kanone L/61. This was the most powerful SPG gun used in combat. Its armour piecing shell could penetrate a 130 mm thick armoured plate sloped at 30 degrees from 2 kilometers. The gun's characteristics were similar to the Soviet 130 mm B-13, which was one of the two guns recommended for Soviet bunker busters. No tank from the Allied side received sufficiently powerful armour to resist such a gun.

However, at the time of creation, the main target for this SPG would have been fortifications, not tanks. The reworked AA gun was ideal for this task. The bunkers of the Maginot Line would not have held against it. The drawback was its mass. It was lower than the AA gun, but still very heavy: 7835 kg. The PzIV chassis was unsuitable for such a gun. The two piece ammunition was also a bad idea in such an SPG.

The Pz.Sfl.V at Alkett, March 9th, 1942.

The only suitable chassis for the schwerer Betonknacker (heavy concrete buster) was the VK 30.01. Henschel's design just underwent a major change in 1939, receiving the blessing of the Motorized Forces Inspector (Inspekteur für Heeresmotorisierung, In 6). However, the tank continued to evolve past that. The suspension was finalized in January of 1940. It's not surprising that development of the SPG took so long. In reality, the development of the vehicle that was indexed Pz.Sfl.V began only in 1940. Henschel was responsible for the chassis.

The same vehicle the with the gun at maximum elevation.

It was clear from the beginning that the vehicle would not have exceptional agility. According to calculations, the SPG would weigh 36 tons. The engine was still the same 11.6 L Maybach HL 116. The layout of the Pz.Sfl.V was going to be very dense. The increasing mass lead to some disappointing news: the top speed of the vehicle would not be greater than 20 kph. The installation of a large and heavy gun also required a serious rearrangement of components. Not only did the engine compartment have to be moved, but the hull had to be lengthened to make it bearable for four men to work in it.

The second Pz.Sfl.V prototype, gun at maximum depression. The strange caption is the work of American intelligence.

The full name of the Henschel and Rheinmetall Borsig design was 12.8 cm Sfl. L/61 Pz.Sfl.V. A contract was signed with Rheinmetall Borsig for four 12.8 cm Kanone L/61 guns. As for Henschel, the company received an order for two Pz.Sfl.V pilots, due in December of 1940. In case of successful trials, 100 SPGs would be ordered.

German command must have been populated by optimists. The VK 30.01 program was behind schedule, and dragged the Pz.Sfl.V with it. While prototypes of the tank were completed in 1940 after all, the SPG continued to exist as a draft. There were no more targets for it, as the Maginot line was taken in May-June of 1940 along with half of France, and no other fortifications that could have impeded the Wehrmacht were left in Europe.

The same vehicle from a different angle. In this position it was possible to service the engine without removing the gun.

The vehicle remained in this embryonic state into July of 1941. Then it was estimated that the prototypes would be ready in August-September, but that was also wrong. The SPGs, now called  Pz.Sfl. für 12,8 cm K40, were only completed by March of 1942. At this point, they had neither a target nor a chassis. The 6th Department of Armament cancelled the VK 30.01(H) program on January 30th, 1942. The chassis of the pilot tanks were converted into training tanks. Although, two of them were used to built the Pz.Sfl. für 12,8 cm K40.

The crew got in through the rear hatch. It was placed so high up that it needed steps.

Little was left of the VK 30.01(H) after the changes. The hull was lengthened by 1.5 meters, which triggered changes to the suspension. A pair of road wheels was added to each side, the return rollers were moved. The number of track links increased to 85 per side. The torsion bars of the last two pairs of road wheels were strengthened to compensate for the increased load. The evacuation hatches on the sides were inherited from the VK 30.01(H), but they were completely redesigned and moved backwards. The left evacuation hatch was used by the driver, but a misunderstanding happened with the right one. It was completely blocked by a fuel tank, and thus was impossible to use.

The left side of the fighting compartment. The gun is marked RV 3. This gun was installed in the second Pz.Sfl.V prototype.

The fenders were taken from the VK 30.01, albeit with some changes. Rear fenders were also attached to the sides of the casemate. The ribbed sheets on the additional fenders were thicker and had a different design. The side panels were also reinforced. The right additional fender held a smokescreen device. The lights and signals were typical for German tanks of that period. Two large headlights were placed in the front with caps for hiding them at night, as well as a Notek night driving light on the left and a Bosch horn on the right. Another Notek light was placed on the rear left, and a Bosch marker light on the right.

Enumerated ammunition rack compartments. The open slots held the shells and the closed boxed hed the propellant.

The entire front, including the upper front plate, was changed. A driver's cabin was installed on the left side. A false cabin was installed on the right, which could be flipped up to reveal the fuel tank cap. Despite a common opinion, this false cabin was present on both vehicles.

A massive casemate that took up more than half of the hull was added to the rear. It was assembled from 15-30 mm thick plates. Most of the roof was open, and only the gunner and commander had small covers over their head. The breech of the 12.8 cm Kanone L/61 occupied most of the space of the fighting compartment, so even its impressive dimensions left it cramped for four crewmen. The gun used an Sfl.ZF panoramic sight, which peeked out of an opening at the top of the roof. The gun was put on a massive pedestal above the Maybach HL 116 engine. The gun could be aimed from -15 to +10 degrees in the vertical plane and from 7 degrees to the right to 5 degrees to the left.

The commander and gunner's stations. The commander does not yet have a radio. The engine was housed underneath the gun, which meant that its replacement turned into a remarkable performance.

The position of the engine under the gun meant that removal, or even repair, was a rather complicated task, especially in the field. In order to allow access to various components, the floor was made up of hinged wooden panels. The ammunition, consisting of 15 rounds with separate propellant (8 AP and 7 HE), was housed in special racks along the side of the fighting compartment. A hatch allowed the crew to enter the vehicle, which was equipped with a ladder for additional comfort. In case of rain, a tarp was provided, which was held on with clips. The vehicle was equipped with a Fu.Spr.Ger.a radio. Its antenna was located on the right side of the casemate, near the commander's station.

Bunker buster to tank destroyer

The SPGs built by Alkett in Spandau had several differences. After the vehicles left the factory, the second prototype received PzIII style tow cable brackets. This was only the beginning of the long list of changes that the Pz.Sfl.V underwent during use.

The second Pz.Sfl. für 12,8 cm K40. The vehicle has the new tow cable brackets, but still retains its false driver's cabin.

It was already clear by late 1941 that the purpose of the SPG would change. The Germans began receiving information regarding the production of superheavy tanks in the USSR. It is not known if these were echoes of the very real KV-3, KV-4, and KV-5, but requirements for a superheavy VK 70.01 tank were ready by November 1st, 1941. The Germans were also impressed by their encounters with the KV-1 and KV-2. It is not surprising that bunker busters were reclassified into tank destroyers. This happened in the spring of 1941, when two Pz.Sfl.IVa were included into the 521st Tank Destroy Battalion.

The results of their use were mixed. On one hand, the firepower of the Pz.Sfl.IVa was greater than that of the 47 mm gun of the Panzerjager I. On the other hand, the vehicles were very slow. Additionally, its ability to penetrate the armour of the KV-1 was never confirmed, as the vehicles were evacuated from the battlefield in both cases by Soviet repair crews. As a result, the Pz.Sfl.IVa was never put into mass production, but the surviving SPG was not removed from service either. The SPG was sent back for refurbishment, then ended up in Jüterbog, south of Berlin, in the spring of 1942.

The first Pz.Sfl. für 12,8 cm K40 prototype in Jüterbog. The false driver's cabin is still present, but the headlights have been removed.

Both Pz.Sfl. für 12,8 cm K40 prototypes ended up in Jüterbog in May of 1942. An order issued on May 15th, 1942, joined these vehicles and the refurbished Pz.Sfl.IVa into a special platoon in the 521st Tank Destroyer Battalion. The crews started to get settled in their vehicles, and that is when they started to change. The false driver's cabins were removed from both vehicles at the same time. Holders for spare track links were added to the left and right of the gun. Holders for spare tracks were added to the front plate as well. In addition, according to photographs, the second Pz.Sfl. für 12,8 cm K40 lost its headlights. The final look of the Pz.Sfl. für 12,8 cm K40 was significantly different from their "factory fresh" form.

Half a year in combat

All three vehicles arrived at the front no later than early July of 1942. A month before that, their battalion was included into the 17th Army Corps of the 6th Army. Between the order being given and the deployment, both Pz.Sfl. für 12,8 cm K40 underwent a transformation. The biggest change was the new headlights with armoured covers, identical to those used on the Pz.Sfl.IVa. Both vehicles received them, which is logical. At least the lights of the heavy tank destroyer platoon were unified.

Moritz soon after arriving on the Eastern Front.

There is little information on the combat use of the Pz.Sfl. für 12,8 cm K40. However, the name they received in combat is well known: Sturer Emil (stubborn Emil). It's not hard to guess why: despite a theoretical top speed of 25 kph, the vehicles could not accelerate past 20 kph. Another cause for the nickname comes from the experience with these vehicles in battle, which will be discussed later.

The name Sturer Emil applied to this type of SPG as a whole. Each vehicle had its own name. According to the report of the commander of the 521st Tank Destroyer Battalion, Oberleutnant Kurt Hilderbrandt, the first vehicle was called Max and the second Moritz, after the mischievous characters. Suffice it to say that their adventures ended poorly.

Powerful armament and skilled application made its mark. However, crews continued to complain about the small ammunition capacity.

As of July of 1942, the 521st Tank Destroyer Battalion included two companies of Marder III (SdKfz 139), one company of Panzerjager Is, and a platoon of heavy tank destroyers (in the second company). Heavy tank destroyers were to be used against medium and heavy tanks, while the Panzerjagers Is dealt with infantry and light tanks. The low speed of the heavy SPGs meant that they had to fire from large distances. Max quickly started showing engine trouble, so most of the work fell to Moritz and the Pz.Sfl.IVa, which was nicknamed "Brummbar". 

Max broke down as usual. Constant issues with the engine and suspension earned the vehicle its nickname "stubborn Emil".

Moritz's crew attained impressive results during the fighting in July. The number of confirmed kills is not known, but one photo shows 31 kill markings on the barrel. According to existing information, the gun was used from 800-1500 meters. Both AP and HE shells were successfully used. Moritz's main opponents were T-34 and KV-1 tanks. Max didn't sit idle. His barrel showed kill marks too, but not as many.

In general, the tactic of using these vehicles for long range shooting paid off. Nevertheless, the soldiers did not like the heavy tank destroyers too much. First, their ammunition capacity was too low. Second, the suspension was overloaded, especially in the rear. As a result, they had to be repaired frequently, often in the field.

Break between battles. In total, Moritz's crew claimed at least 31 tanks during the summer of 1942. An impressive result, especially for an experimental vehicle.

Intensive use made its mark on the vehicles, especially Moritz. The rear was overloaded, which lead to rapid wear on the road wheels. As a result, a pair (and sometimes more than one) of spare road wheels often found itself in place of the false driver's cabin. Lots of other items were usually stored on top. On the left fender, behind the jack block, two 20 Liter canisters and their holders were installed. Several photos show a box above the crowbar, mallet, and metal cutter holders, but it was likely not permanently attached. Another box was welded underneath the antenna mount, the others seemingly were just lying on the fender. The number of boxes varied from one to four.

Moritz closer to the fall of 1942. Issues with road wheels forced its crew to carry spares on the roof of the hull.

Max couldn't brag about such additional equipment. Unlike his brother, there were no spare wheels, and only one box was added to the right fender (right after the jack block). However, the extra rear fenders were not empty. The left was always covered in items covered with rags, the second held a jack. Moritz's crew went even further: on the rear right of the casemater there was a vertical holder for a jack, and another jack was placed on the fender, like on Max. The tarp was held in the same way on both vehicles: on the rear side of the casemate roof.

Big trophy

The 521st Tank Destroyer Battalion remained in the 6th Army through the fall-winter of 1942. Sadly, the information on the combat performance of the "Emils" is sparse, and no photos are known. It is only known that both vehicles were a part of the battalion on November 12th and were fighting near Stalingrad. As of December 1st, only one vehicle was listed in the battalion. Presumably, Max had been lost by then. The 521st battalion ceased to exist in January of 1943, sharing the fate of the 6th Army.

Captured Pz.Sfl. für 12,8 cm K40, February 1943.

The Red Army learned that the Germans had a powerful anti-tank SPG by late October of 1942. The source of this information is very interesting. It was described in the information bulletin of the GAU Artillery Committee:

German 150 mm SPG. A dead German gefreiter named Wilhelm Wise from the 1st Battalion of the 190th Artillery Squadron near Voronzeh had a photo on him, which allows us to deduce that the Germans equipped an SPG with a 150 mm gun.
The same vehicle at an exhibition in Moscow.

The dead soldier had a photo of the Pz.Sfl.V made during training in Jüterbog during the spring of 1942. Moritz, which the Germans abandoned along with the other vehicles of the 521st battalion, fell into the hands of the Red Army. It was captured near Novoalekseevka village, which is north-west of Stalingrad. At the moment of its capture, Moritz was undergoing repairs, and there were seveal wheels missing from the right side. Interestingly, the number of victory marks on the barrel was reduced to 7. Perhaps it has to do with a change in crews.

The same vehicle from the front. Remnants of the tow cable holders characteristic of Moritz can be seen.

The SPG was delivered to the NIBT proving grounds in Kubinka. Due to a lack of components, mobility trials were skipped, as were gunnery trials (because of a lack of ammunition). A brief description was composed in March of 1943, which was very precise. The description was composed using information from prisoners of war, which pointed out that the SPG was used in a special unit. This unit was tasked with fighting Soviet medium and heavy tanks from long range. The prisoners also said that firing on mobile vehicles from the heavy SPGs was difficult.

The vehicle was later repaired. Presently, the right side has all of its wheels. The ones that were lost were replaced with newly made wheels.

An idea for creating an analogous SPG using a 122 mm A-19 gun on a KV-1 chassis was pitched after this information was received. In a way, one can consider this the starting point for the creation of the ISU-122, although the real start of the A-19 SPG program was in April of 1943, when a captured Tiger was tested.

From this angle, you can see that the fighting compartment interior was still present. Today, the casemate is completely empty.

After the vehicle was studied, it was sent to an exhibition of captured armament in Gorky Park. It remained there for quite some time. The captured SPG attracted the attention of American soldiers. They asked to take the vehicle for study, but the request was denied. The vehicle was not a secret, but this was the only sample in Soviet hands.

Unlike many vehicles from that exhibition, which were scrapped in 1948, this vehicle escaped that fate. The SPG returned to Kubinka, where all of its components were removed and sent for study. The SPG was placed on display. Today, it can be seen on display in the Kubinka Tank Museum, a part of Patriot Park. Perhaps the vehicle will later be moved to the park's main display area.

Drawings of the SPG and its characteristics made it into reference books composed after the summer of 1943.

Despite only one SPG being captured, it left its mark in history. Studies of the sample made their way into specialist literature. Information about the vehicle was included in reference books. And reports of sightings made their way from the front. For example, on July 20th, 1944, an Elefant from the 653rd Tank Destroyer Battalion was mistaken for a "128 mm SPG". This vehicle was used in an ambush which the 71st Guards Heavy Tank Regiment fell into. As a result, three IS-2 tanks were lost and three knocked out. The commander of the regiment, Guards Lieutenant Colonel Yudin, died in this battle.

Lieutenant Slyunyaev's IS-2 knocked out the enemy vehicle. On the 24th, he destroyed another one, at Magerov. In some documents, this vehicle was also listed as "128 mm SPG".


Street Fighter

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"March 21st, 1937
#4250ss
To the chief of the ABTU, Divisional Commander Bokis

CC:
Chief of Armament of the Red Army, Army Commander 2nd Class, comrade Khalepskiy
Chief of the General Staff, Marshal of the Soviet Union, comrade Yegorov

Experience in using the T-26 tank demonstrated its poor suitability for fighting in cities, where the tanks took heavy losses. There is no reason to assume that other types of tanks will perform any better. We much have tanks that are especially designed for successful street fighting, not only in small settlements, but in large cities, where the enemy will have the ability to attack our tanks from above.

Discuss this issue (invite Arman and Krivoshein) with specialists: engineers and designers. Report to me in 20 days regarding your ideas for a tank that is designed for street battles.

Consider the following:
  1. The tank should, in my opinion, possess considerable penetration. It should be able to destroy not only barricades of all types, but also stone obstacles: walls, houses, etc, which means that the front part of the tank should be reinforced and shaped like a battering ram. Think this idea over.
  2. It must be possible to fire machineguns, or, more desirably, cannons up at an angle of 60-70 degrees to hit the enemy on top floors of houses. This requires good visibility upwards and to the sides.
  3. The tank crew must be protected from incendiary fluid.
  4. Speed can be sacrificed for improved armour, especially in the front, but not agility.
  5. The rear of the tank must be covered by fire.
  6. It is desirable to have a BT-IS-like Tsyganov convertible drive.
  7. It is desirable to protect the tracks from hand grenade bundles.
These are the requirements, in very general terms, for a tank designed for street (city) fighting. Report your ideas on the topic and on timelines for designing an experimental prototype, if you consider this tank necessary at all.

K. Voroshilov."

British Tiger II Intel

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The British, impressively enough, were already aware of the King Tiger long before ever seeing it in combat, at least by May of 1944.


On July 18th, 1944, the Germans lost three King Tigers on the Western Front. It doesn't look like the British noticed them, however.

The following information was published in September of 1944. It's largely correct, but some errors are present. Complete information about the King Tiger would not be published until February of 1945.


T-34-85 Armour

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Even after the end of WWII, the T-34-85 continued to be a relevant threat, and thus demanded study. This measurement of a T-34-85 turret's armour thickness made in West Germany in 1961, however, suggests that the study could have been a little bit more precise.




The rest of the measurements, however, seem a lot more reasonable.




Pistol Penetration

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Penetration (or, rather, overpenetration) is an important topic for small arms as well as artillery. In this document, several different pistol rounds are compared in their ability to punch through 11 dry pine boards from a distance of 25 meters.


The guns in the list are:
  • "Mod. 1930" (likely TT-30)
  • Voyevodin's design
  • Browning (likely Hi-Power)
  • Lakhti-35
  • Star 7.63 mm
  • Borchardt-Luger
  • Colt M1
  • Mauser 7.65 mm
  • Sauer
The note on the bottom says that the Star pistol was using 7.62 mm model 1930 cartridges, more commonly known as 7.62 Tokarev. As you can see, that particular pistol was the most impressive, penetrating 8 boards with 10/10 shots, and the only gun to make a hole in the 10th and 11th board. The TT-30 doesn't do as well, only conquering 6 boards, but that's still better than the .45 bullet of the 1911 (3 boards) and 9 mm Luger (4 boards).

Via kris_reid

Pz.Kpfw.II Ausf. G: The Fruit of Unending Labour

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The idea of replacing the La.S.100, or the PzII, with a superior vehicle was born in January of 1937. The result was the La.S.138, otherwise known as the PzII Ausf. D and Ausf. E, created by MAN and the famous tank designer Heinrich Kniepkamp. The tank had a progressive torsion bar suspension, but its service did not last for long. It was clear that the story of the La.S.138 was developing poorly by the summer of 1938, before the tank even entered production. The result of this understanding was the development of another tank, which was supposed to replace both the La.S.100 and La.S.138.


VK 6.01 for three

On June 18th, 1938, In 6 (Inspekteur für Heeresmotorisierung, Inspection of Motorized Forces) initiated work on a new tank. In the new system of indexes that Kniepkamp took part in creating, the project was dubbed VK 9.01 (fully tracked, 9 ton weight class, type 1) in October of 1938. The developer remained the same. Like with previous projects, MAN designed the chassis and Daimler-Benz worked on the turret platform and turret. The general concept of the PzII family also remained the same. The vehicle held three people: the commander, also serving as the gunner and loader, was in the turret. The driver and radio operator were located in the forward compartment. Like in the La.S.138, they sat shoulder to shoulder.

The armament was also identical: a 20 mm autocannon and an MG 34 coaxial machinegun. However, there was a difference here: a vertical stabilizer, which improved accuracy on the move. The armour was on the level of the La.S.183: 30 mm in the front and 14.5 mm along the sides. This meant that the vehicle was protected from 20 mm autocannons from the front and rifle caliber bullets from the sides.

Experimental VK 9.01 chassis at the MAN factory.

The  VK 9.01 was developed in tight cooperation with Kniepkamp, which had a direct influence on its design. It looks like the designer didn't reinvent the wheel and reused what was available. This was the light VK 3 t tank, which was designed by Krauss-Maffei and Kniepkamp starting in October of 1937. The project evolved into the VK 6.01 by the summer of 1939. This design was used as the foundation.

Even the naked eye can see how similar these two tanks are. The further the design work proceeded, the more obvious it became. Essentially, this was the same VK 6.01, but larger, especially width-wise. The need to fit three people instead of two into the tank meant that it had to be wider. The turret was also very similar, only with different dimensions and armament. It's not known if Kniepkamp tried to install tracks with rubber pads similar to those used in halftracks on the VK 9.01, like he did on the VK 6.01.

The fighting compartment of the experimental and mass produced PzII Ausf. G. The biggest difference was a different gearbox.

A commission from the 6th Department of Armament arrived at the MAN factory in Nuremberg on October 11th, 1938, where they was shown a wooden model of the tank. A meeting was held on the same day, which was attended by leading MAN engineers Friedrich Rif and Paul Wibike. At the start of his career, when Kniepkamp was working at MAN, he was Wibike's subordinate. The main objective of this visit was, of course, to view the model. Kniepkamp and other representatives of the 6th Department were worried about the dimensions of the fighting compartment. Hardly any equipment was installed, and it was already very small.

Work continued, and the VK 9.01 and VK 6.01 became more and more similar, both externally and technically. Both received the 150 hp Maybach HL 45 engine and an 8-speed semiautomatic Maybach SRG 15319 gearbox. The VK 9.01 had a three stage LG 45 turning mechanism. Like on the VK 6.01, it was controlled via steering wheel. The suspension was similar to the one used on its little brother, and even the diameter of the road wheels was the same: 650 mm. The design of the road wheels was also very similar.

Experimental prototype of the VK 9.01 with the turret and turret platform installed.

After improvements to the initial design, MAN received a contract for five experimental VK 9.01 chassis. In 6 also signed a contract for 30 pilot VK 9.01 tanks, increased to 75 in July of 1939. Simultaneously, a contract for the same number of turrets and turret platforms was signed with Daimler-Benz.

By proud tradition, these plans were altered soon after they were confirmed. In August-September of 1939, a new variant of the tank called VK 9.02 appeared. It had a modernized LG 45 L turning mechanism, later renamed to LGL 15319. According to new plans, the first 30 tanks of the pilot batch would be called VK 9.01 and be equipped with LGR 15319 turning mechanisms, the rest would be VK 9.02s. The first 5 VK 9.01 chassis were planned for July of 1940, 10 more in August, 10 in September, and 5 in October.

However, it was clear that these deadlines would change in July of 1939. The completion of the chassis was moved to November of 1940, and the finished tanks were not expected until November of 1941. All that could be done in 1939 was the completion of one experimental VK 9.01 chassis in December. Since the fate of the tank was predictable, it was decided that it would be replaced with the PzII Ausf. F equipped with a stabilizer in case of failure. This is what happened in the end, except the PzII Ausf. F never received the stabilizer. At a meeting held on April 25th, the VK 9.01 was referred to as Pz.Kpfw.II n.A.

Where daydreams lead

The second half of 1940 was full of further changes to the tank and production plans. For instance, on July 25th the number of LGR 15319 equipped tanks was reduced to 20, and the remaining 55 would receive the LGL 15139 turning mechanism. Production plans were changed in November: 45 VK 9.01 chassis were now expected from MAN between May and September of 1941.

One of the pilot chassis during testing of the Maybach gearbox.

Meanwhile, all signs pointed to the fact that the production run of the VK 9.01 would be limited to its pilot batch. On June 22nd, 1940, In 6 put out an order for a new 10 ton class light tank with improved speed characteristics and 20 mm armour on its sides. The vehicle was indexed VK 9.03. The increased weight would be compensated by a 180 hp Maybach HL 66 P engine. A larger engine triggered the redesign of the engine compartment. It became a little larger. The armament initially remained the same as on the VK 9.01.

MAN prepared the first calculations for the VK 9.03 projects in July of 1940. The turning mechanism was the same as on the VK 9.01, but the gearbox was replaced with the Maybach VG 20417. Further development was dedicated to reinforcing the suspension. The length of the contact surface increased to 2.08 meters and the width of the tracks from 300 to 360 mm.

The Germans had many plans for the modernized vehicle. According to the tank development program, approved on May 30th, 1941, 2592 VK 9.03 tanks were expected for initial saturation of the tank forces, and subsequent orders looked even more impressive: 8111 units. It is likely that the vehicle would have been modernized. The indexes VK 9.04 and VK 9.05 were already present in documents.

A dummy weight was used to simulate the turret platform.

While debates about the future VK 9.03 raged on, the fate of the VK 9.01 was grim. Yet another replacement of gearboxes took place in April of 1941. 5 tanks would be built with the Maybach OG 20417, 5 more with the ZF SMG 50.  The first chassis of the Pz.Kpfw.II n.A. was built that month, and the number of chassis reached 15 by mid-August. The result of the new gearboxes was poor: 2 of the Maybach OG 20417 and 5 ZF SMG 50 broke during trials at Kummersdorf.

As you can see, the tanks were tested in combat-like conditions.

Various corrections to the VK 9.03 continued. As a result, the tank remained on paper by the end of 1941. For instance, the idea of making a more powerful gun based on the 28 mm Geschütz 8202 (also known as the 2.8 cm sPzB 41) anti-tank rifle. The appearance of such a project was predictable, since the 20 mm KwK 30 and KwK 38 were no longer sufficient. The new gun would be called 2.8 cm KwK 41, and later, due to delays, the name was changed to 2.8 cm KwK 42.

A VK 9.03 with a two man turret could have looked like this. This version would have been called Pz.Kpfw.II Ausf. M.

Another change to the yet-unborn VK 9.03 was made in December of 1941. In addition to the single man turret, the Heereswaffenamt (Directorate of Armament of the Land Forces) ordered the development of an alternative variant with a two man turret. Daimler-Benz was developing this turret for the VK 13.01 reconnaissance tank, better known as the Pz.Sp.Wg.II Luchs. Since there were already 3 tanks under the index VK 9, they received additional indexes. The VK 9.01 was called PzII Ausf. G, the VK 9.03 was called PzII Ausf. H, and the version with two man turret received the name PzII Ausf. M. The two man turret variant would weigh 10.5 tons, and its mobility and protection would remain at the level of the VK 9.03.

Another potential replacement could have touched the gearbox. A diesel engine was discussed in February of 1942. This engine, with a power of 180 hp, was created at MAN in 1939. In March 1942, the idea of installing a 400 hp Maybach HL 100 engine into the VK 9.05 was considered. The issue of replacing the gearbox and turning mechanisms with those that BMM designed for the Pz38(t) n.A. tank was also discussed.

A production PzII Ausf. G with a tropical camouflage.

All of these dreams were ruthlessly shattered on March 27th, 1942. MAN received a letter from General Emil Leeb, the head of the Heereswaffenamt. The brass was tired of these designers' games, especially since work on the VK 9.03 has not yet progressed past a handful of half-finished chassis. With the VK 13.03 on hand, a further development of the VK 13.01, the development of another similar tank was excessive. Work on the VK 9.03 and its derivatives ceased.

Tank with serial number 150021 during the unfortunate trials of the ZF SMG 50 gearbox.

Unlike its prospective replacement, fate smiled on the VK 9.01. However, the plans for production kept changing. In addition, there were delays in production of the turrets and turret platforms at the Daimler-Benz Wrk 40 factory in Berlin. The first sets of steel did not arrive until the fall of 1941. In total, MAN built no fewer than 45 PzII Ausf. G chassis, and Daimler-Benz supplied 60 sets of turrets and turret platforms. It is not known how many of these became fully fledged tanks. There is also no information about how many tanks received what kind of gearbox. As mentioned above, three types of gearboxes were used.

One of the tanks ended up in a training unit. Its subsequent fate is unknown.

The final variant of the VK 9.01 fell within the requirements that it was built to. The mass grew to 10.5 tons, but the mobility did not suffer much. The top speed on a highway was 67 kph, but it was limited to 65 kph. Overall, this was a decent reconnaissance tank. However, the VK 13.03, a much more suitable candidate for this role, entered trials in the spring of 1942. It's not surprising that production of the VK 9.01 did not progress past an incomplete pilot batch. MAN was also taking on more and more work on the Panther tank, and there was simply no time for light reconnaissance tanks.

The PzII Ausf. G on the front lines. It is not yet known which unit it belonged to.

The combat history of the PzII Ausf. G is a bit question mark. It is known that the 15th Tank Division was pegged as the first unit to receive these tanks. However, these plans were made in February of 1941, before the first pilot vehicles left MAN. Nevertheless, the tanks built in August of 1941 were painted in RAL 8000, the colour of Africa Corps tanks. It's not known what happened to them after that. Most tanks likely ended up in training units.

Nevertheless, claims that the PzII Ausf. G never saw combat are incorrect. Photographs periodically surface in internet auctions that demonstrate that these tanks ended up on the Eastern Front. However, it has not yet been possible to establish the time these photos were taken or what unit the tanks belonged to. Many white spots exist in the history of the PzII Ausf. G that have yet to be filled.

Quick Tank Destroyer

Many permutations of the VK 9.01 design did not prohibit the Germans from considering its chassis for the role of an SPG in the summer of 1940. The result of this was the use of Panzerjager I tank destroyers in the French campaign. Overall, the vehicles performed well, but it was clear that the PzI Ausf. B was not the ideal choice of a chassis. The 50 mm Pak 38 gun was nearing the final stages of development, and it was superior to the Czechoslovakian 47 mm PUV vz.36. More importantly, it was produced in Germany. It is not surprising that, on July 5th of 1940, In 6, and later the 6th Department of Armament, ordered Rheinmetall-Borsig to develop a tank destroyer that used the chassis of the VK 9.01.

One of the two prototypes of the Pz.Sfl.Ic.

The design of the vehicle called Pz.Sfl.Ic was finalized towards the end of the spring of 1941. Even though the VK 9.03 was considered more promising at that point, Rheinmetall-Borsig, which tasked Alkett with the development, decided to go with the VK 9.01. Considering that this chassis was actually built in metal, this was a reasonable choice.

The chassis remained nearly unchanged, but the side armour was increased to 20 mm with applique armour. An altered turret platform was used. It became wider, since a fighting compartment for two men was planned instead of the one man turret. Instead of a turret, an immobile open-top casemate was used. A slightly altered 50 mm Pak 38 was installed in the front. In part, its recoil mechanisms were redesigned to take up less room in the fighting compartment. A movable gun shield covered the crew from the front and partially from the sides.

The vehicle was not incredibly roomy, but it was more promising than the Panzerjager I. Aside from improved armament, the Pz.Sfl.Ic had increased mobility, and fair protection for its vehicle class. At the very least, high caliber machineguns would not be a fatal threat.

Pz.Sfl.Ic on the front lines, summer-fall 1942.

The Germans had great plans for the Pz.Sfl.Ic. The total production run would be for 2028 units. Unfortunately, the changing requirements and various improvements made the production of even the VK 9.03 more and more distant. The SPG was a hostage in this situation.

Nevertheless, two experimental vehicles were built in the fall of 1941, both using armour steel. The Pz.Sfl.Ic program was killed by two factors. The first was that the VK 9.03 program died in March of 1942. The second was that the 75 mm Pak 40 entered production, which was much more powerful than the Pak 38. The VK 9.01 chassis could not mount it. Knowing this, In 6 launched a program to design a tank destroyer with a 75 mm gun on the chassis of the La.S.138, better known as the Marder II. Nevertheless, the Pz.Sfl.Ic reached the battlefield. Both experimental vehicles were sent to the 3rd battery of the 559th Tank Destroyer Battalion. They fought on the Eastern Front as a part of this unit. By August 20th, 1942, one of them was still combat ready.

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