Friday, 31 October 2014

ZiS-6 Project

"To the director of the Kirov factory, comrade Zaltsmann
To the GABTU Chief, Lieutenant-General of the Tank Forces, comrade Fedorenko

On the issue of mounting the 107 mm ZiS-6 gun in the KV-3 tank

Attached is the project for the installation of a 107 mm ZiS-6 gun in the KV-3 tank, which has the following characteristics:
  1. Muzzle velocity: 800 m/s
  2. Recoil resistance: 20,000 kg
  3. Mass of the recoil components: 1600 kg
  4. Mass of the oscillating components with the mantlet: 2600 kg
  5. Recoil length: 640+40 mm
  6. Shell: single piece
  7. Breech: semi-automatic
  8. Coaxial machinegun: DT
  9. Vertical gun range: +20 to -5
  10. Maximum vertical gun range obtainable with recoil brake: +40 to -15
  11. Fume extraction with compressed air is possible
  12. Shell casing length: 625 mm
  13. HE round length: approximately 1200 mm
  14. Initial return mechanism pressure: 50 atmospheres
  15. Sight: TD
  16. Mantlet: same as in the KV type turrets
  17. The gun will be tested in the KV-2 turret
Factory #92 is finishing the design of the ZiS-6. Despite this late stage, some improvements noted by your engineers will be made. Some of your requested changes cannot be made, as they require approval by the factory (the frame and mantlet are fixed in our design). 

The request from your engineers to use a two-piece shell goes against the decision of the party and government, which factory #92 will not allow. On our side, factory #92 did everything possible to ease the loading of a one piece shell, including making the gun as compact as possible.

In order to resolve the issue of two-piece loading, contact the appropriate authorities.

Factory director [signature]
Chief Engineer Grabin"

Thursday, 30 October 2014

AA T-80

Many people know of the T-90 AA tank, a T-70 with AA machineguns that could reach a high elevation, but fewer know that there was also an attempt to make such a tank on the T-80 platform.

"Based on experiences of tanks fighting in cities and in mountains, GABTU requested that Artkom develop tank guns that can fire with elevation of up to 70 degrees. Therefore, tank guns based on the M-42 currently being tested should have depression to -6 degrees and elevation of up to 70 degrees. The recoil brake and return mechanism should be tested at maximum elevation.

Due to the high elevation, the recoil is allowed to be variable, and the recoil brake must be strengthened. An additional return mechanism mounted on top of the gun in the mantlet is allowed. In order to provide smooth braking, the recoil brake must be variable at various elevations.

If tank guns based on the M-42 are nearing completion and these changes will be difficult, it is necessary to begin designing new prototypes that satisfy the above requirements."

However, before testing a fancy new gun at high elevation, it's reasonable to try it with an old gun. Doing this revealed some problems.

"The T-80 tank design proposed by comrade Astrov, deputy chief engineer at the GAZ Molotov factory, is an interesting design, as it offers the possibility of shooting at enemy aircraft.

At the same time, the T-80 has a series of drawbacks, such as:
  1. The angle of elevation (65 degrees, 60 in the prototype) is not enough for quality AA fire, which requires an angle of elevation of at least 85 degrees.
  2. The rate of fire is 14-15 RPM, which is not enough for an AA gun.
  3. The sights are primitive and observation from the turret is limited, which is unacceptable for an AA gun.
  4. The recoil mechanisms do not operate in normal conditions, and a knocking is heard when the gun is returned at low elevations, requiring a new recoil brake and return mechanism combination.
The first three drawbacks severely limit the value of the T-80 as an AA platform and will turn up during proving grounds trials, if any take place. Raising the issue of adopting the tank after only 375 trial shots at the factory is premature.

It is necessary to at least partially resolve defect #4 and resolve defects #1-3 using the resources of TsAKB engineers at factory #92, the complete resolution of which requires a drastic redesign of the T-80 tank."

Wednesday, 29 October 2014

Leningrad Front, Fall 1941

I already posted about the variety of vehicles that fought on the Eastern Front way past their obsolescence, and here are some more that show up in a table listing available vehicles on the Leningrad Front for September 27th, 1941.

The first column of each unit lists vehicles that are fully repaired, the second lists vehicles that are subject to minor repairs. The last two columns tally up the vehicles for both categories among all units, and the bottom row totals up the total amount of vehicles for the unit (armoured cars in the numerator, tanks in the denominator). The units listed are as follows: 123rd Tank Brigade, 124th, Tank Brigade, 42nd Army, 55th Army, 23rd Army, 115th Infantry Division, 8th Army, 21st NKVD Division, and Front Reserves. The vehicles listed are KV, T-34, T-28, BT-7, BT-5, BT-2, T-50, T-26, flamethrower tanks (likely T-26 modifications), BA-10 and BA-20 armoured cars.


Given the proximity of Kirov factory, the amount of KV tanks available for combat is not surprising, and neither is the amount of T-34s being overshadowed by older vehicles, like the BT series and T-26es. Six entire T-50s defend the northern capital, but I don't know if the Kirov prototype is one of them, or is not listed due to being owned by the factory instead of a military unit.

The previous article also mentions the 124th Tank Brigade, but about 13 months later, allowing us to track some of the more interesting vehicles. For instance, right now it has zero BT-2s, but two of the Front's 19 BT-2s can be found among its ranks in a year. Only two of the 51 KV tanks remain, replaced with other obsolete vehicles that migrate among the Front's units.

Tuesday, 28 October 2014

85 mm Gun Range

I talked about the doctrine of applying heavy guns of the IS-2 and ISU-152 from a long range (1500-2000 meters). What about lower caliber weapons, such as the 85 mm gun? The 5th Guards Tank Army has us covered, with its "Brief instructions several issues of using units of the 5th Guards Tank Army, arising due to partial reorganization of tanks and artillery in the army", dated May 21st, 1943, publied in Collection of Combat Documents from the Great Patriotic War, vol. 15, doc. 4.
The contents of the document are as about as brief as the title, but all the way at the bottom lies the answer to this question.

"Additionally, corps commanders should be aware that a 85 mm gun battery from the 6th AA artillery division has been assigned to each corps to assist in fighting enemy tanks, specifically T-6 (Tiger), tasked with fighting the enemy at long range (1500-2000 meters). Remember that the 85 mm gun is capable of penetrating any German tank at 1500 meters and knocking it out at 2000 meters. The one exception to this is the T-6 when hit in the mantlet and front. When hit in the side, turret, suspension, the T-6 is knocked out from 2000 meters by 85 mm guns just like any other German tank."

Monday, 27 October 2014

IS-2 and ISU-152 Manual

Despite my best efforts, many people still believe that Soviet heavy guns were inaccurate and were incapable of engaging the enemy at long range. Here is another nail in that coffin with the "Directive of the Military Council of the 1st Ukrainian Front on the use of IS-2 and ISU-152 regiments in combat" published in Collection of Combat Documents from the Great Patriotic War, vol. 2, doc. 7.

"The practice of use of heavy tanks and SPG regiments in combat shows that IS-122 and ISU-152 tanks are the most effective method of fighting enemy heavy tanks (Tiger and Panther) and SPGs (Ferdinand), as well as destroying enemy artillery and fortifications.

IS-122 and ISU-152 regiments are used to strengthen tank or mechanized corps, and in rare cases, infantry corps.

The use of IS-122 and ISU-152 regiments as a part of tank or mechanized units achieves significant results in combat, which is confirmed by the actions of these regiments on the 1st Ukrainian Front."

The specifics of the combat examples have little to do with the point of the document, and have extracted them into other articles. It is sufficient to say that IS-2 tanks that opened fire from 1500-2000 meters in several cases and ISU-152 SPGs that opened fire from 1400-1500 meters in the other achieved very palpable results. Continuing on, here is that the Council has determined that the correct application of these heavy vehicles entail:

"The combat use of IS-122 tank regiments and ISU-152 SPG regiments

The off-road performance, armour, mobility, and constant readiness to open fire allows SPGs to follow tank and infantry units and constantly support them with heavy fire.

The IS-122 and ISU-152 should open direct fire at ranges of up to 2000 meters. Most effective fire is from 1500 meters.

Tanks fire from short stops, from open, half-open, and if possible, concealed positions. Tanks and SPGs follow medium tanks or infantry from one position to another, combining fire and maneuver, not lagging behind the battle. If tanks or SPGs lag behind, their knowledge of the battlefield is reduced, and they cannot fire timely. The flanks of heavy tanks should be covered with medium tanks or infantry with artillery.

Additionally, each heavy tank or SPG should have a submachinegunner escort.

Competent use of terrain increases effectiveness, reduces losses, and aids in achieving surprise attacks at the enemy. The terrain shape, upper layer of soil, and off road performance have significant impacts on the mobility of heavy tanks and SPGs. Swamps, wide and deep rivers, wet plains are difficult obstacles, and must be scouted out in a timely nature.

Reconnaissance of the battlefield must commence as soon as orders are received and continue throughout the battle. The task of the scout is to discover the condition of terrain and roads, presence of bridges and their capacity, possibility of approaching the enemy while hidden, and priority objectives for tanks and SPGs to destroy.

Observation of the battlefield is of utmost importance. In the regiment, HQ officers observe the battle from Observation and Communications Points. Vehicle and unit commanders observe the battlefield from their vehicles, or personally on foot (or prone). The results of observation must be immediately communicated to the commander by radio or a messenger.

The regiment commander commands his companies or batteries with radios, messengers, or rockets. Using other types of communication increases the reliability of command. In battle, orders to fire are usually given in cleartext, but the names of units and names and ranks of the commanders must be given in code. The regimental commander's first priority is to keep in contact with whoever his unit has been assigned to. In battle, he must be present within the ranks of the regiment, from where he may control his companies or batteries and, in a critical moment, inspire his men with personal courage.

1. Marches.

The regimental commander and his HQ provide seamless marching conditions by means of scouting out the route and locations nearby.

The movement speed on good roads is 20 kph. Average speed is no less than 15 kph (10 kph on mountainous terrain). Weather and specifics of the road lead to significant variance in speeds. When marching on mountains on serpentine roads with sharp turns, more time must be alotted, as stops to inspect the vehicles must be more frequent. The regiment marches company by company (battery by battery). One company (battery) follows another after a set length of time. When operating in operational depth without immediate contact with the enemy, the battery must be ready to deflect enemy counterattacks.

2. Offensive.

The IS tanks and ISU-152 SPGs have the same off-road performance and maneuverability as medium tanks. Because of this, they can accompany tanks and motorized infantry during offensives. The commander of the unit to which the regiment is assigned and the regimental commander organize the movement of the regiment, determine objectives and how they should be achieved, the location of the regiment in the order of battle, a joint communications system, and the methods of communication.

The regiment, as a rule, drives forward in the second echelon, 300-500 meters behind medium tanks or infantry. Its place is the location of the main strike, along a 1000-1500 meter wide front. The main purpose of the IS and ISU tanks is to destroy enemy tanks and SPGs, as well as deflect enemy counterattacks.

When attacking, close terrain with an uneven landscape and good ability to observe is favourable. Uneven landscapes protect the IS and ISU from enemy close combat measures.

When penetrating an enemy defensive line, IS and ISU tanks may be used in the first echelon to destroy fortifications.

Some of the tanks may be used in assault groups. For this, they are assigned to infantry regiments and are distributed among assault battalions. Tanks, operating carefully on their terrain, attack fortifications as a part of assault groups, opening fire at 1500 meters or closer.


3. Defense.

IS and ISU tanks are a powerful anti-tank defense method, and can serve as a mobile anti-tank reserve. Its place is in the direction the enemy is most likely to attack from. When defending, tanks should be placed in cooperation with anti-tank guns.

An IS-122 regiment or ISU-152 regiment is placed in an interleaved manner along a 2.5 km wide and 2 km deep front. When defending, terrain that is open while the tank itself is concealed is preferred.

The first line of defense is infantry, artillery, and medium tanks. Behind them, 500-600 meters away, are 2-3 companies of IS and ISU tanks. 800-1000 meters behind are the rest of the regiments's tanks, acting as a mobile reserve.

Crews ready 2-3 positions for their tank, one of which is the main one. They must be connected by hidden paths. All positions must be equipped with trenches that cover the hull of the tank or SPG, and carefully hidden. In order to fire precisely and effectively at enemy tanks, prepare firing cards.

It is reasonable to keep tanks hidden, and only move them out when the attack starts. If there is no time to make hidden paths, take up positions along routes that only reveal a portion of the turret. In both cases, each tank and SPG must carefully observe the battlefield. Always be ready to meet enemy tanks and repel them.

It is reasonable to let enemy tanks get as close as possible.

When firing at 1500 meters, the IS and ISU can destroy any enemy heavy tank. It is especially favourable when the enemy shows his side.

When deflecting the enemy's attacks, a useful method is to fight in pairs. One tank shoots, while the other watches enemy maneuvers, and assists the first tank.

The method of ambushes has proven itself. Ambushes are placed in likely directions of enemy attack, with the objective of letting enemy tanks close, then destroy them with sudden aimed fire.

Otherwise, follow the Armoured and Mechanized Forces manual parts 1 and 2.

The use of IS-122 tanks and ISU-152 SPGs in front of infantry and medium tanks or as immobile guns is forbidden.

Commander of the Armoured and Mechanized Forces of the 1st Ukrainian Front, Lieutenant-General Novikov
Deputy Commander of the Armoured and Mechanized Forces of the 1st Ukrainian Front, Major-General Petrov"

In case someone thought that this long range use is specific to the 1st Ukrainian Front, a similar order is given by the Commander of the Armoured and Mechanized Forces of the Red Army (Order #484120, published in vol. 15 doc. 9):

"Heavy tanks and SPGs open direct (generally) fire: at tanks from ranges up to 2 kilometers, at large targets (concentrations of enemies, artillery positions) from 3 kilometers.

Heavy tanks and SPGs fire from stationary positions (ambushes), from short stops, and on the move (at large targets)."

Sunday, 26 October 2014

Cheating at Statistics 9: Art Imitates Life

Continuing the theme of investigating the battles specified in "Directive of the Military Council of the 1st Ukrainian Front on the use of IS-2 and ISU-152 regiments in combat", here is another engagement, this time between Tigers of s.Pz.Abt 509 and Soviet IS-2s from 72nd GTTP and ISU-152s from 399 GTSAP.

Schneider's records of this battle favour the German side:

"19 April 1944: 18 Tigers support the attack on Isakow, but they erroneously attack to the south in the direction of Podwerbce. Belatedly, some tanks close in on Isakow, preventing enemy forces from escaping to the south. In conjunction with the 101. Jager-Division, which is attacking from the east, the enemy forces are totally destroyed by the Tigers."

When records of both sides are compared, I have often found that "totally destroyed" forces tend to not notice their total destruction at the hands of Tiger battalions, and continue pushing on. In those cases, the Tiger unit tends to clear out of the area of operations, usually with heavy losses. 

"20 April 1944: The battalion gathers in the area of Buczacz (3 of 29 Tigers operational) and is transported to Kolomea. It remains there as a field-army reserve and a training unit for Hungarian crews on the Tiger tank."

Thought so. Let's see how much "total destruction" 15 lost Tigers achieved. The Germans are attacking southwards from Buchach (the previously recorded location in the diary), so it's very possible that they took a slightly wrong heading and ended up in the neighbouring Podverbtsy. Unfortunately for them, heavy Soviet guns were waiting north of Gerasimov.

"The 72nd Guards Heavy Tank Regiment was assigned to the 11th Guards Tank Corps, and was tasked to fire from an ambush. in a second echelon, 1.5-2 km from the front line. It took up positions in houses north of Gerasimov.
...the enemy penetrated our defenses at Podvertse and Zhivachuv. IS-122 tanks opened fire from a distance of 1.5 kilometers. As a result, 6 tanks were knocked out and 3 burned, 6 of which were Tigers."

"399th GTSAP was assigned to 11th Guards Tank Corps, and by 7 am set up in the ranks of 27th Motorized Infantry Brigade, with the objective of not letting the enemy break through Navziska and Gerasimuv from Zhivachuv.
...after an artillery barrage, 7 enemy tanks attacked the motorized infantry. The batteries opened fire from 1400-1500 meters. First shots ignited several enemy tanks. The rest advanced and tried to hit from the flank, despite fire from the SPGs.  On the left flank, 10 enemy tanks started flanking the batteries. In order to liquidate the menace, a reserve battery was deployed, which knocked out three tanks with one volley. The rest of the tanks withdrew.

The regiment fought for 7 hours, deflecting tanks and infantry. As a result, the enemy attack failed, and they were stopped at the road between Zhivachuv and Navziska. Total enemy losses: 13 tanks (6 burned and 7 knocked out) and up to 100 soldiers and officers."


So we have 18 Tigers that attacked southwards. The Soviets claimed 6 Tigers knocked out in the initial attack, "several" knocked out by SPGs an hour later when 7 tanks attacked, and three more knocked out when 10 tanks attacked their flank.  This makes a total of 9 Tigers, and 4 other unidentified tanks (perhaps also Tigers, the diary doesn't mention cooperation with any other unit). The Germans go from 18 Tigers supporting the attack to 3 Tigers during their withdrawal the next day. A claim of 13 Tigers is entirely reasonable in this engagement, with two more Tigers that could have been knocked out by other means or bogged down somewhere.

The German claims in this engagement remind me of a certain Star Trek episode. The first thing that came to mind was "You look, er, quite well for a man who's been... utterly destroyed, Mr. Spock."

Saturday, 25 October 2014

Heavy Tanks in Combat

On April 16th, 1944, heavy fighting raged on around Ternopol. Soviet forces encircled the city, and the Germans trapped in their fortress no longer wished to remain there. Here is a rare case where both sides committed their biggest tanks to the fighting.

The 53rd Guards Tank Brigade received the 11th Guards Heavy Tank Breakthrough Regiment, three companies of new IS-2 tanks, on the night of April 16th. That morning, a company was readied to defend the small town of Pochapintse.

The Germans committed their Tigers from s.Pz.Abt 507. These Tigers, as well as 9th SS "Hohenstaufen" and elements of SS Division Galizien (which appeared to have spent the previous day torching the village, according to Nieukarane zbrodnie SS-Galizien z lat 1943—1945). 

With the two forces less than seven kilometers apart (and a seven minutes' drive, according to Google, although neither the Tigers nor ISes would have managed it that fast), a confrontation is inevitable. Schneider says:

"16 April  1944: Relief attack continued with 12 operational Tigers in support. Several antitank positions  were  wiped out and Hill 363 was captured. Initial contact with the defenders of Tarnopol was established."



Hm, rather laconic. The Soviet record of the battle is much more in depth.

"At 10:30 on April 16t, 1944, the enemy attacks with a force of up to 25 tanks and two battalions of infantry, and at 16:00 with 40 tanks. At a high cost, the enemy managed to displace elements of the 53rd GTBr. 

Heavy tanks (one company), placed behind the medium tanks, opened intense fire at a range of 1500-2000 meters. As a result, 13 enemy tanks were destroyed, (3 Tigers and 10 Panthers). The crew of Guards Lieutenant comrade Vovk showed themselves well, knocking out four enemy tanks (one Tiger), as well as Guards Lieutenant Timokhin, knocking out three enemy tanks (one Tiger).

The enemy attack was repelled, and its tanks returned to initial positions."

It's interesting to note that despite the Panther's thicker armour, it is the Tigers that are considered a more prestigious prize. Now, how closely does the Soviet description matches the Germans' records. I cannot say for sure how many Panthers the Germans lost, but Wielhelm Tieke writes that 9th SS came in with 24 Panthers, which makes the claim of knocking out ten of them feasible. Counting knocked out Tigers, however, is a much easier feat.

"17 April  1944: The 2./schwere Panzer-Abteilung 507 attacked north of Seredynki; it had eight  operational  tanks."

12 - 8 = 4, so that means the Soviet count was correct. Not only that, but the Germans managed to lose another Tiger elsewhere, or someone confused a Tiger for a Panther. The Soviet record that the Germans failed to displace them is also confirmed (despite some casual Googling turning up opinions that 9th SS somehow won the engagement), as they are attacking the same target from a different location the next day. It appears that this Hill 363 was of no help to them. 


Again, the Germans had no luck at all.

"18 April  1944: The relief attack bogged down and a withdrawal was  executed during the night. One company remained in support of the XXXXVIII. Panzer-Korps. Eight tanks reported operational; seven of them with  the 1./schwere Panzer-Abteilung 507."

Eight tanks remain in the German battalion. You may have noticed that I have omitted mention of the 1st company until now. The thing is, Brody is quite a ways away from where the fighting was taking place, so it would have had no effect on this engagement.


The Germans attacking Pochapintse have failed, losing 11 Tigers and at least 10 Panthers against the defending IS-2 company. 

Friday, 24 October 2014

Anti-tank Posters

I've already shown some Soviet anti-tank posters, but here are some more. These are pre-war, and contain a little more information about the tank aside from where to shoot it.


First, we have a "light tank type 2", which is quite clearly a PzI Ausf. B. The dimensions of the tank and maximum armour thickness are almost correct, the weight is a bit off, but the top speed (50 kph) is completely ridiculous. The tank is credited with the ability to break a 25 cm thick tree, climb a vertical obstacle 60 cm tall, a grade of 40 degrees, a body of water 80 cm deep, and a 1.6 meter long trench, all of which are nicely represented graphically at the bottom of the image. Similar graphics show that the battalion cannon can penetrate it at a range of 1200 meters, and a machinegun can do so at a range of 800 meters. Despite the picture showing a Maxim gun, the fine print reads "with a high caliber machinegun".


Then we have a "light tank type 2 B", which is a PzII. The mass, size, and speed data is much better, than for the PzI, only the weight is a little higher than it should be. All other information is communicated in the same manner.


Now we get to an interesting one, a "medium tank type 3 B", which is an early PzIII (looks more like an Ausf. D than an Ausf. B), one that still had 8 wheels and leaf springs. Very few of these tanks were produced. Intelligence is doing its job!

Thursday, 23 October 2014

2-pounder HE

Many lamentations have been recorded about the lack of explosive shells for British 2-pounder guns. One solution I've seen involved jury-rigging smoke launchers to fire mortar shells. Another is a little more reasonable.

"A program of trials of 40 mm English high explosive fragmentation tracer AA shells in tank guns
  1. Goal of trials: to establish the possibility of using 40 mm AA shells in a tank gun. Before trials, the following work is done:
    1. The 40 mm shell is disassembled.
    2. The possibility of firmly loading an AA high explosive fragmentation shell into a tank shell casing is tested. The firmness of the load is tested by loading the shell into a tank gun.
    3. The tank gun rifling and shell driving band are measured in order to discover the necessary forcing of the band for satisfactory loading of the shell (not having the driving band prematurely stick into the rifling).
    4. The maximum pressure the shell can bear is calculated by examining mechanical characteristics of the shell and its size.
  2. Supplies for trials:
    1. System: 40 mm English tank gun.
    2. Shell: 40 mm English AA high explosive shell.
    3. Casing: from the 40 mm tank gun.
    4. Propellant: propellant from the English AA shell and domestic propellant with ballistic characteristics close to English 40 mm shell propellant.
  3. Trial process:
    1. Discovery of the propellant load to achieve V0=790 m/s and pressure less than the maximum acceptable pressure calculated in point 4.
      Note: according to information possessed by Artkom, the maximum acceptable pressure for the 40 mm AA high explosive fragmentation tracer shell is 3000 kg/cm^2. This information needs to be confirmed.
    2. Discovery of the propellant load to achieve V0=790 m/s using domestic propellant following points 1 and 3. Propellant will be tested on inert shells. If it is not possible to disarm the shells, testing will be done on shells that are incompletely armed with an inert detonator.
      If it is not possible to achieve a velocity of 790 m/s without surpassing acceptable pressure, trials will continue with the maximum velocity attainable at this pressure.
    3. Further trials will be carried out according to typical testing procedure applicable to HE shells (aside from point 1), using the propellant load established in these trials. Increased pressure is considered 1.1 times the current working pressure.
The trial report should include data for the formation of ballistic tables. The report should also include English markings on the 40 mm shells."

Wednesday, 22 October 2014

Experimental SPG Work, January 1944

"To the member of the State Committee of Defense, comrade L.P. Beria

On the letter from the People's Commissar of Tank Production, I report:
  1. GAU supports the NKTP's request to cease producing the 130 mm gun, indicated in the GOKO degree issued on December 27th, 1943.
    GAU does not take part in the arguments between NKTP and TsAKB on the possibility of installing a 130 mm gun into the SPG on the IS chassis, knowing that if the organizations are willing to make concessions, a decision that satisfies both sides can always be reached.
    GAU considers it necessary to cancel the 130 mm SPG, as it requires a more reasonable and mass produceable artillery system for tanks and SPGs, which is possible to build in 1944.
  2. Our current SPGs with 122 mm and 152 mm guns model 1937/43, with ballistics of corps level guns A-19 and ML-20 are powerful weapons against German heavy tanks and SPGs, but it is necessary to further increase the firepower of these weapons.
    These requirements are confirmed by developments of the arms race on the battlefield and possible technical progress by our enemy.
    Considering this scenario, OKB-172 has designed a high power 122 mm SPG gun according to GAU specifications, indexed OBM-50. The technical project has been reviewed and approved by Artkom on December 18th, 1943. An experimental prototype has been ordered, and should be completed by factory #172 in February. The production of the 122 mm OBM-50 gun is confirmed by GOKO decree #4851ss issued on December 27th, 1943. In order to perform factory and proving grounds trials of the 122 mm high power gun, we need you to order the People's Commissariat of Ammunition to produce new tube nitroglycerine propellant.
    GAU considers this gun equivalent in power to the 130 mm gun proposed by comrade Grabin, but the 122 mm high power gun has many advantages over the 130 mm gun.
  3. The 152 mm OBM-43 gun is a completely different class of weapon than comrade Grabin's 130 mm gun, and can't be compared.
    The OBM-43 has been built according to GAU specifications as a towed gun. It is possible to install it in an IS SPG using the oscillating part and mount from the 152 mm model 1937/43 SPG gun (SU-152), which was ordered by comrade Malyshev and carried out by factory #100 and OKB-172 engineers.
    This 152 mm gun is not fully developed and is only an intermediate step, and its trials are of little interest. GAU does not oppose the transfer of the 152 mm OBM-43 gun from the NKV to factory #100 for mounting in an IS SPG to carry out trials at the Gorohovets proving grounds with assistance from the GBTU in order to test several design solutions and use cases.
  4. The installation of a special 152 mm SPG gun with the ballistics of the OBM-43 in an SPG has been foreseen by GAU. The project for such a gun, indexed OBM-53 has been reviewed and approved by Artkom on December 18th, 1943, at the same time as the OBM-50 project.
    No prototype is being produced, as the NKV has not issued the appropriate orders to factory #172. I ask you to order the People's Commissar of Armament, comrade Ustinov, to produce an experimental OBM-53 152 mm SPG gun by February 25th.
    GAU considers the 152 mm OBM-53 gun to be a very powerful weapon, and, due to design specifics and high power, it cannot be a mass produced tank escort weapon. It must be built in limited numbers to achieve objectives set by the Supreme Command.
  5. GAU supports the NKTP proposal to test a 100 mm gun designed by factory #9. At the same time, GAU considers it necessary to test the 100 mm gun designed by TsAKB.
  6. Along with the 100 mm gun, GAU considers it necessary to test an 85 mm gun with the muzzle velocity of 1000-1100 m/s.
    This gun has nearly the same firepower and penetration as the 100 mm gun, but the weight and size give it an advantage over the 100 mm gun, both of the gun and the shell.
    Additionally, the production of an 85 mm gun and ammunition for it would not pose any difficulty, as the design of the new gun and its shells is an organic progression from the existing items produced at NKV and NKB factories. Savings in metal (approximately 30% for the gun and 40% for its shells) are also a benefit.
  7. When installing powerful guns with barrels from 5600 mm (85 and 100 mm guns) to 7000-7500 mm (122 and 152 mm guns) in length, the barrel will exceed the front of the SPG by at least 3500 and up to 5000 mm (with the 152 mm gun). Because of this, when moving off-road, it will hit objects and terrain, which will cause damage to the gun and knock it out during battlefield maneuvers.
    In January of this year, the commander of artillery of the 3rd Ukrainian Front sent a report to GAU, regarding the SU-85 SPG. In this SPG, the barrel exceeds the length of the SPG hull by about 2300 mm. The report says that when going over obstacles, there were cases of sand getting into the barrel, and strong enough hits against the ground that the normally reliable sliding shaft of the elevation mechanism bends, and the SPG cannot be used. The possibility of this happening with high power SPGs is much greater.
    Measures suggested by the NKTP (pushing the barrel back by 800 mm, 10 degrees of gun elevation) help only on the march, but not in combat, where damage is being done to these guns.
    Based on the above, GAU considers it necessary to, in parallel with the design of new powerful guns, to design new SPGs with rear fighting compartments (like the SU-76).
    This will preserve the high combat maneuverability of SPGs and allow the increase of their front armour.
  8. The armament of a self propelled gun must not only be examined from the point of view of increasing the firepower of tank units, but from the point of view of increasing the firepower of infantry units, maneuverability and firepower of special tank destroyer units, and creation of special weapons for the Supreme Command Reserve.
    GAU considers it necessary to have the following weapons in self propelled artillery:
    1. Infantry support SPGs
      1. 76 mm ZiS-3 gun (F-34) on a light SPG chassis made from T-70 components.
      2. 122 mm D-5 howitzer or 152 mm D-15 howitzer on a medium SPG chassis made from T-34 components.
    2. Tank escort SPGs
      1. 85 mm D-5 gun (with AA gun ballistics) on a medium SPG chassis made from T-34 components, already in production.
      2. 85 mm high power gun or 100 mm gun on a medium SPG chassis made from T-34 components, planned for production in 1944.
      3. 122 mm D-25 gun or 122 mm A-19S gun or 152 mm mod. 1937/43 gun, already in production, installed on a chassis made from IS tank components.
      4. High power 122 mm OBM-50 gun on an SPG chassis made from IS tank parts, planned for production in 1944.
    3. Supreme Command reserve SPGs
      1. 152 mm OBM-53 gun installed on an SPG chassis made from IS tank parts, planned for production in 1944.
      2. 203 mm howitzer on a half-covered chassis made from IS tank parts.
    4. Tank artillery
      1. Medium tanks:
        1. 85 mm D-5 gun (AA gun ballistics) or 85 mm high power gun.
      2. Heavy tanks:
        1. 122 mm D-25 gun.
        2. 100 mm gun or 85 mm high power gun.
  9. GAU considers existing artillery systems in tanks and SPGs incomplete. The correlation between quality and quantity of SPGs still needs refinement. Attempts to correct this balance, as experience shows, appear as individual and sometimes poorly thought out proposals from many design organizations. The demands of the front and capabilities of production are not considered.
    When these individual projects are built, antagonistic relationships form between organizations. This can cause unrefined prototypes to be pushed into production prematurely or the opposite, a delay before introducing this weapon into the Red Army.
    In order to bring order to the design of tank and SPG armament, GAU deems it necessary to hold a meeting of representatives of the General Staff, GBTU, GAU, NKV, NKTP, NKB, and design organizations in order to refine tank and SPG artillery systems.
Red Army GAU Chief, Colonel-General of Artillery, Yakovlev
January 24th, 1944"

Tuesday, 21 October 2014

T-40 Cost

Many times have I read the opinion "the USSR was a totalitarian state, Comrade Stalin could wave his hand and make anything cost as little as he wanted!" Those people may have learned their history from this comic book, but for the rest of us, here is a fragment of reality:

"Record of disagreement between GABTU and factory #37 on the topic of supplying T-40 tanks in 1941

Customer version:
  1. T-40 tank: regular, with individual parts and instruments kit and armament, 81,000 roubles.
  2. T-40 with radio: 71-TK-3 with a battery or 10-R with parts and instruments kit and armament: 86,000 roubles.
February 26th, 1941

Supplier version:
  1. T-40 tank: regular, with individual parts and instruments kit and armament, 135,000 roubles.
  2. T-40 with radio: 71-TK-3 with a battery or 10-R with parts and instruments kit and armament: 135,000 roubles:
    1. Cost of a 71-TK-3 radio station: 2850 roubles
    2. Production, installation, and testing of the radio station: 2000 roubles
      The cost of installing, testing, or producing a radio is not included in the 135,000 roubles.
March 3rd, 1941"

Monday, 20 October 2014

World of Tanks History Section: Oboy Epicycloid

The end of the spring of 1915 was tough for the Russian Empire and its armies. An Austrian and German offensive that started on May 2nd threatened the entire front and the territory of the Polish Kingdom.

On May 4th, 1915, a fascinating letter reached Nikolai II's office, addressed personally to the Tsar. Its author was one Ivan Fedorovich Semchishin, a citizen of the city of Lvov, which was a part of the Russian Empire as of September of 1914. Semchishin's lack of fluency in Russian [unfortunately, the curious turns of phrase are lost in translation] was compensated by flowery prose and creativity. The letter was titled "A project of a machine for crushing trenches and military fortresses", and was immediately sent to military specialists at the Technical Committee of the Chief Military-Technical Directorate (GVTU). This organization processed proposals and inventions, which came in significant volume.

Changing the Landscape

The military engineers were no strangers to radical ideas, but Semchishin's project overcame even their imaginations. The author wrote: "If we had a large armoured barrel or roller with a motor inside which can spin on its axis, we could drive it over our enemies. My project, composed of a mobile fortress, realizes this principle and can be used to destroy fortified regions. It is called "Oboy"".

The author wrote of an armoured ellipsoid (which he called "epicycloid") of colossal size: 605 meters tall and 960 meters wide. Oboy's armour could withstand the enemy's bullets and shells, as well as mines. Two hatches were planned at each end, covered with robust caps. The crew would climb into them with 300 meter long rope ladders. Inside, the vehicle was equipped with a command post, projectors, and a wireless telegraph station.

Until recently, the Oboy was considered to have no armament, but archive documents show the opposite. The vehicle had provisions for heavy artillery. The design also included a sewer system, a ventilation system, a gas line, as well as "electric wires, telephones, elevators, fans, etc". The many floors of the vehicle would have hallways with living quarters, workshops, and stores. Semchishin's proposal was more than a house, but a whole mobile city.

The Oboy had no wheels, as it was itself a wheel. The vehicle would be propelled into motion by a system of steam engines, pendulums, and dynamo machines. The system produced "stores of energy, kinetic and potential". A flywheel would rotation into a rocking motion, allowing the ellipsoid to roll. The author did not specify how powerful this engine would have to be, but his design called for a mind-boggling maximum speed of 321 kph.

The engineers' verdict was laconic and absolute: the project is infeasible.

What if?

The military was correct. But now, after a century of technical progress, let's try to figure out why.

First of all, the Oboy would be impossible to build. There is no assembly plant today large enough to accommodate its size. Semchishin's supertank would have been taller than skyscrapers. There are also few buildings wider than 900 meters, none of which are capable of motion.

The vehicle would have to have been built near the front lines. In any other case, it would have expended its engine lifetime moving towards it, changing the landscape in its path.

The assembly of a prototype would be impossible to conceal from the enemy. If a team of saboteurs would be unable to impede such a colossal project, then an artillery barrage or a bombing run would leave it defenseless.

Even if the technology was available, the vehicle would crush itself when it moved. A mere 100 mm of armour would crumple like tinfoil under the Oboy's colossal mass.

A year later, another inventor proposed an idea of new armour. Using a cloth weaved from 1.9 cm thick rope and "so tightly wound that it would become like stone". This cloth, 71 cm thick, would be backed by 10 cm of steel. Even this invention, decades ahead of Soviet or American composite armour, would not protect the giant from its fate.

Two and a bit decades later, in July of 1943, the idea was reborn in miniature. Engineer-mechanic A.S. Dashevskiy proposed an ellipsoid "moving fortress". Its armour was 200 mm thick, but it was only 2.5 meters in diameter and 5 meters long. Dashevskiy's vehicle was like a mini Oboy.

Many spherical vehicles were proposed in the first half of the 20th century. Today, they become more and more known to those interested in military history. The Oboy "fortress destruction vehicle" remains the largest armoured vehicle designed in history.

Article author: Yuri Bakhurin. Yuri Bakhurin is a military historian, an author of many publications in regional and central scientific press: "Questions of History" magazine, "Military-Historical Magazine", "Military-Historical Archive", "Motherland", "Anthology of War", the "Reitar" almanac, and many more. He is also the author of the "Panzerjager Tiger (P) Ferdinand: Use in Combat" book.

Sources and literature:
  • RGVIA 803-1-1828 p. 123-134
  • RGVIA 803-1-1816 p. 140 and reverse
  • Y. Pasholok, Stalniye Shary Stalina, Moscow, Tactical Press, 2014
Original article available here.

Sunday, 19 October 2014

Kazantsev's Tankettes

"Excerpt from the orders of the enemy 339th infantry division from July 8th, 1942 (data of the 339th division intelligence)

Russian bombs (land torpedoes)

Army Group South has seen the use of bombs, invented by engineer 3rd grade Kamertsev (according to prisoners). Data on their size differs widely. According to one prisoner, it is 3.5 meters long, another says 1.5. Width: 1-1.5 meters, height: 0.75-1.25 meters. The explosives load also varies, one prisoner said 150-200 kg, another said 200 kg.

The bomb is mounted on a small tank (tankette), moving at 20 kph, connected by three cables to a dug in BT tank, which is its source of energy. Each BT tank can release two bombs, remotely controlled, and moving in a zig-zag pattern. The cable is up to 5 km long. The bomb explodes when it reaches its target using a detonator. If the cables are hit and torn, the bomb will explode in 7.5 minutes. The prisoners mention that these bombs are unsatisfactory, and there were losses when cleaning up stuck or dud bombs."

CAMD RF 38-11355-651

Saturday, 18 October 2014

World of Tanks History Section: Morozov's Top Ten

On October 16th, 1904, one of the most talented Soviet tank engineers, Alexander Alexandrovich Morozov, was born. He lived for 75 years, and gave nearly two thirds of his life to tanks. He started out a blueprint copier at a Kharkov factory, then served as a rank and file engineer, then section chief, then chief engineer. Morozov was never on the front lines, but his tanks took part in battle from the first days of the war.

He continued designing tanks after 1945, and his vehicles set the trends of Soviet tank design. Here are ten vehicles from this exceptional engineer's career that can be called exemplary.

1. BT-7. 

The convertible drive BT tanks were one of the main components of the RKKA tank forces before the war. The BT-7 was the last of this family.

The BT-7 was armed with a 45 mm gun, could reach speeds of 70 kph, and had anti-bullet armour. In the late 1920s and early 1930s, this armour was standard in nearly every army, but in the late 1930s, it was no longer enough.

The BT series served as a chassis for new technical solutions, like the installation of a 76 mm gun or experiments with sloped armour (BT-SV).

The BTs fought in the Spanish Civil War, at Khalkin-Gol, during the Winter War. In June of 1941, Soviet mechanized corps that were still armed mainly with BT-7s took the brunt of the Wehrmacht's offensive.

2. A-20

In 1937, a new tank for the Red Army was being developed. The A-20 still used the convertible drive, such was the requirement from the military. Externally, it had little in common with the BT-7, aside from large road wheels, characteristic of the Christie suspension.

The tank had a welded hull and a new turret. The armour plates were sloped to increase the chances of a ricochet. The front armour was up to 20 mm thick. The tank could accelerate up to 80 kph on a highway.

The vehicle was never mass produced. The only A-20 ever built fought with the 22nd Tank Brigade. Engineers, including A. Morozov, managed to convince the military that a purely tracked vehicle was better than a combination of wheels and tracks, and so the A-20 was not needed.

Morozov and his bureau did not waste their time. The A-20 was the predecessor of a vehicle that earned its legendary title.

3. T-34

The T-34 needs no introduction. Countless books and articles have been written about it. The T-34 fought in the Great Patriotic War from the first day to the last as the workhorse of the Red Army.

At the start of the war, this tank's 45 mm thick armour and 76 mm gun made it one of the most powerful tanks in the world. The Germans only managed to surpass it in armour and firepower with the Tiger, Panther, and Ferdinand.

The first T-34s were far from ideal, and were improved greatly throughout the war. A T-34 built in 1943 was significantly different from a T-34 built in 1940-41. Morozov played a key role in all of the tank's modernizations and improvements.

4. T-43

The tank was supposed to be a descendant of the T-34, but the design differed greatly from it. Due to a superior placement of components and alteration of the hull, the level of protection rose drastically. The front armour was increased to 75 mm. The tank used a torsion bar suspension, which was more compact than the T-34's Christie suspension.

The T-43 was better armoured, but this also made it heavier. Its ground pressure came close to that of heavy tanks.

The tank was accepted into service, but was not placed into production, as the military demanded an 85 mm gun. The T-43 was so tightly coupled that there was no potential for modernization. Introducing it into production demanded the development of new technological processes, which the USSR could not allow in time of war.

5. T-34-85

The main problem with the T-34 was that in 1943, its gun was no longer sufficiently powerful. In the middle of 1943, it was decided that n 85 mm gun will be installed. In order to do this, engineers developed a larger turret with better armour, big enough for three crewmen.

The 85 mm ZiS-S-53 gun was based on an AA gun design, and provided superior penetration. This increased the effectiveness of the T-34 when fighting new German tanks. The vehicle retained excellent mobility.

It cannot be said that the T-34-85 was a radical leap forward that gave Soviet forces unparalleled supremacy, but this was a necessary and timely replacement of the T-34.

6. T-44

This tank was the leap forward. It seemed similar to the T-34-85, but its internals differed greatly.

The T-44 had a new diesel engine, placed perpendicularly across the hull. This allowed the turret to be moved further back to balance the suspension. The driver's hatch was removed from the front plate, which raised the vehicle's protection. All components and mechanisms were improved.

The Christie suspension was replaced with torsion bars. This allowed the tank to be smaller and have more room inside, making life easier for crews and repairmen.

The T-44 was accepted for service in 1944, but it had no time to serve in battle, partially due to the fact that Soviet leadership did not wish to reduce the number of T-34-85s being produced. 2000 T-44s were built after the war.

7. T-54

Another leap forward. Designed in 1946, the T-54 remained in the Soviet design school for a long time. The first vehicles had expected growing pains, but after being improved, it became a reliable and technologically efficient vehicle with a large resource for modernization.

The T-54 had a new rounded turret with up to 200 mm of front armour, an improved hull, improved transmission, and a series of other improvements. The vehicle had a 100 mm D-10T gun, which, for a while, was the most powerful tank gun in the world. Its shell could penetrate 125 mm of armour at 2000 meters.

The T-54 was used by about 30 countries worldwide, and participated in many 20th century conflicts.

8. T-55

The T-55 was developed in 1958, and had many improvements over the T-55. One of the most important ones was the installation of a full anti-radiation system. The tank had a semi-automatic rammer. The caliber and type of gun were the same as on the T-54.

The T-55 remained in production until 1979. It fought in many conflicts, and 30 countries still use it to this day. More than 10 foreign variants of the vehicle exist.

The T-55 could reach 50 kph on a highway, and its range was up to 500 km on one tank of fuel.

9. T-64

The vehicle made for a new 115 mm gun, also known as "Object 432". The tank was in production from 1960, and was a laboratory of sorts for engineers and technologists. The vehicle turned out very complicated and not exceptionally reliable. Many were built before it was accepted into service, for testing by the army. The information that came back from the military was used to continue perfecting the design.

In 1966, Object 432 was approved for service. It had a 115 mm smoothbore gun. The tank's armour was composite, and used materials other than steel to defeat HEAT shells and protect from radiation. The same armour was used on the T-64A.

10. T-64A

In the end of the 1950s and start of the 1960s, the age of Main Battle Tanks began. The MBT concept called for a tank that could perform many tasks, combining mobility, firepower, and protection.

The T-64A was accepted into service in 1969. The tank had an automatic loading mechanism, which allowed manual shell type selection. Because of this, the loader was excluded from the crew.

This was the first Soviet tank to use an optical rangefinder. It had the same composite armour as the T-64. It is hard to say whether or not the T-64A was the best tank in the world, but in the 1990s, Western military specialists admitted that it would have been a very dangerous opponent.


About the designer: 

Alecander Alexandrovich Morozov was born on October 16th, 1904 in the village of Bezhitsa, located inside the modern boundaries of Bryansk. After finishing a "real academy" (an educational institution with a focus on natural sciences and mathematics), he worked at the Kharkov Locomotive Factory. He was a file clerk, then a copier. From 1926 to 1928, he served as an aircraft engine technician.

In 1928, he returned to HPZ. Despite its peaceful title, this factory was one of the key Soviet producers of armoured vehicles, including tanks.

In 1931, he finished a machine-building college, and became a group chief in the factory's design bureau. In 1936, he was promoted to section chief. In 1938, he was promoted to Deputy Chief Engineer.

Before the war, he worked on the T-24 tank and BT tanks. Along with Mikhail Koshkin and Nikolai Kucherenko, he worked on the future workhorse of the Red Army, the T-34 medium tank.

When Koshkin died in 1940, Morozov became Chief Engineer. In 1941, the factory was evacuated to Nizhniy Tagil. Here, Morozov directed the development of the T-43, T-34-85, T-44, and T-54. After the war, Morozov designed the T-55, T-64, and T-54A.

The T-54 earned Morozov his third USSR Government Award. He earned two Hero of Socialist Labour titles and two first class Stalin Awards. In 1972, Morozov was awarded the title of Doctor of Technical Sciences.

Original article available here.

Friday, 17 October 2014

Tiger II Trials: Visibility

"Visibility from the tank

The Tiger B tank has the following observation devices:
  • Telescopic ball sight
  • Fire correction periscope
  • Optical machinegun sight
  • Ten periscopic observation devices
The telescopic ball sight with adjustable magnification and field of view is installed left of the gun. The head of the sight is attached to the oscillating part of the gun, and the eyepiece is attached to a support on the turret roof. The field of vision is 25 degrees with 2.5x magnification and 12 degrees 30 minutes with 5x magnification. 

The fire correction periscope is carried in the turret bustle. When in use, it is mounted on the commander's cupola. The field of view of the fire correction periscope is 6 degrees, magnification is 6x, periscopic width is 1250 mm.

The optical machinegun sight is attached to the radio operator's machinegun and has 1.6x magnification, field of view of 18 degrees, and a 6 meter dead zone.

10 periscopic observation devices are placed in four points: seven of them are in the commander's cupola, one each for the loader, radio operator, and driver. The commander's observation devices are all identical and are positioned in a circle on the vertical armour of the cupola. The periscopes have the following field of view:

Device position
Field of view (degrees)
Dead zone (meters)
Horizontal
Vertical
Front
65
25
11
Front right
65
18
19
Right
65
15
25
Rear right
65
20
15
Rear left
65
22
12
Left
65
25
11
Front left
65
25
11

The vertical field of view and dead zone of the observation devices is variable due to the commander's cupola being offset to the left side of the turret roof.

The periscopic sight of the loader is immobile in the right front of the turret. It has a horizontal field of view of 57 degrees, vertical field of view of 18 degrees and dead zone of 28 meters.

The periscopic sight of the gunner is immobile in the roof of the fighting compartment. It has a horizontal field of view of 60 degrees, vertical field of view of 16 degrees and dead zone of 11 meters.

The periscopic sight of the driver can turn in its mount in the roof of the driver's compartment. It has a horizontal field of view of 60 degrees, vertical field of view of 16 degrees when immobile, or up to 100 degrees horizontal and 40 degrees vertical with rotation. The dead zone is 7 meters.

Figure 9: Sight range (horizontal)


Figure 10: Sight range (vertical)"

CAMD RF 38-11355-2860

Thursday, 16 October 2014

Nezhinets' Wonder-tank

"To the GABTU chief, Lieutenant-General of the Tank Forces, comrade Fedorenko

From a student of the VAMM Stalin Military Academy, Lieutenant Nezhinets, Ivan Ivanovich

From May 1938, I worked alongside Military Technician 2nd Grade comrade I.M. Sharalapov on orders from Colonel-General of the Tank Forces, comrade Pavlov. We completed all tasks assigned to us.

In response to my letter in May 1940 addressed to Colonel-General Pavlov, Colonel-General Pavlov replied with orders to develop special equipment for tank units. This equipment has been developed by comrade Sharalapov and I, and a new universal tank designed to use it.

This tank uses a new 300 hp diesel type engine, which burns fuel in a different way and a hydraulic gearbox. There is no electric starter, which makes the tank easier to maintain and resistant to various rays. The suspension has a convertible drive, the hull and turret are aerodynamic in shape. The conical turret has a rotation mechanism. The gun has a loading mechanism, which lets the third crewman work on fire correction and other equipment which will be used in more difficult combat situations.

The tank has a mass of approximately 14 tons, with a maximum speed of 100 kph. If one or two track links break on one track, the tank does not stop moving, due to an improved chassis. Driving the vehicle will be made simpler due to a lack of clutch. In the winter, the vehicle can be heated by recycling air.

When tanks are used in more difficult combat situations, it is equipped with special devices which protect the crew from anti-tank rifles and poison gases (the tank is air-tight). The engine is cooled with special devices. The driver's controls are two-sided, making it easy for large tank units to make 180 degree turns in tight spaces and makes vehicles more maneuverable in combat.

The vehicle is designed for improved independence from other vehicles. It is equipped with a hydraulic compressor to generate pressurized compressed air, with several advantages over the one designed in 1939. The compressed air can be used to:

  1. Start vehicles.
  2. Operate tow cranes when the engine has broken down.
  3. To repel poison gases.
  4. To clean the vehicle from dirt and dust.
  5. For other specialized uses.
Such a vehicle can also be equipped with a trailer.

Comrade Lieutenant-General, allow me to report to you more detailed combat and technical characteristics on this vehicle.

Lieutenant Nezhinets
February 7th, 1941"

Wednesday, 15 October 2014

Seelow Spotlights

Many people have heard of spotlights being used to blind the Germans when storming Seelow Heights, but details are not as widely available. Lucky for you, I have you covered.

"The peculiarities of a nighttime attack to penetrate enemy defenses on the West shore of the Oder river

A distinctive feature of the Berlin operation was the use of nighttime artillery barrages and infantry attacks in order to achieve greater surprise.

Over two days (April 14th and 15th, 1945) before the attack, reconnaissance was performed to discover the true location of the enemy and the possibility of retreat to a second line of defense. Reconnaissance in the early morning forced the enemy to increase the level of caution and rouse the front line for deflecting attacks at dawn. In these conditions, attacking at night, before dawn, would achieve a complete surprise.

Among measures taken to ensure the success of a nighttime offensive, the use of projectors in the breakthrough region deserves attention. According to personal orders from Front commander, Marshal of the Soviet Union comrade Zhukov, 140 projectors were installed near the front lines. The projector units were tasked with lighting up the path of our infantry and blinding the enemy when the attack started (5:30 on April 16th, 1945).

Projector units arrived at their positions in the second half of April 15th and were subordinated directly to the artillery commanders of the infantry corps. Infantry division and regiment commanders were familiarized with the nature of the upcoming illumination, but did not participate in its execution directly.

12-15 projectors were placed in the path of an advancing infantry corps (2.5-3 km wide), 200-250 meters apart, 1 to 1.2 kilometers away from the front line. The projectors were removed from their trucks, and placed 2 meters above the ground. The control center for the projector companies was placed near artillery corps HQs.

It was impossible to create an even illuminated front due to the uneven terrain. Because of this, corps and division commanders took measures to ensure that infantry kept their heading. Special "azimuth men" were trained, one per infantry company. Special night units were formed for regiment and battalion commanders. These units were tasked with sending signals, illuminating terrain not covered by projectors, and marking the direction of battalion movement with tracers. These units contained handheld machineguns with large amounts of tracer rounds, as well as flares. The boundaries between advancing regiments were marked with 76 mm tracer shells.

At 5:00 on April 16th, 1945, the artillery barrage began, lasting for 25 minutes. At 5:25, specially designated projectors signalled "attack" with vertical beams, and the remaining projectors turned on their horizontal beams.

Due to technical difficulties and damage from enemy machineguns, it was impossible to achieve full and simultaneous illumination on the area of attack.

The projectors were placed 1-1.2 km behind the front line to provide illumination for 3 km into enemy territory. In practice, this could not be achieved on some sections of the front lines, as the artillery barrage kicked up a large cloud of dust and smoke that remained in the air for several hours (even after dawn). Projectors could not penetrate this cloud, and the penetration of some was quite shallow.

Nevertheless, the desired effect was achieved. In most cases, the light from projectors, even with gaps, helped infantry orient themselves and hold their heading. Tanks and infantry in zones lit up by projectors moved much faster and with more confidence than infantry and tanks that advanced in darkness.

It must be noted that the sudden illumination of enemy positions demoralized his infantry and blinded machinegunners and artillery observers. The enemy was passive in areas illuminated by projectors. Conversely, the enemy opened heavy fire from some darkened sections at advancing units. In order to minimize these dark regions, one infantry corps successfully panned their projectors by 65-70 degrees (see attachment #1).

Despite some deficiencies in illuminating the terrain with projectors, the rate of advance was sufficiently fast. In one hour, infantry and tanks moved 1.5-2 km into enemy lines.

The following conclusions can be made from studying the experience during the Berlin operation:

  1. Projectors should create a continuous front. If there are not enough projectors, projectors should sweep back and forth to blind remaining enemies and prevent flanking fire from darkened areas.
  2. Divisional commanders should be tasked with coordinating projector units, placing projectors before the attack, and directing the projectors as infantry and tanks advance.
  3. In infantry units, despite the ability to signal with projectors, practice directing infantry with beams and tracer trajectories.
  4. When illuminating terrain during attacks, keep in mind that projectors cannot penetrate the smoke and dust kicked up by an artillery barrage. The brightness of a beam is inversely proportional to the distance; with increasing distance, the brightness is greatly reduced. Keep this in mind when calculating the brightness of projectors necessary for illuminating certain positions."
And of course, here is the attachment.

CAMD RF 233-2356-775

Solid lines represent immobile projectors, and dotted lines represent the area covered by projectors that pan back and forth.

Tuesday, 14 October 2014

Effectiveness of German Infantry Anti-tank Measures

VIF2NE poster panzeralex dug up some figures from Guderian's Inspector General of the Tank Forces archives on the effectiveness of Panzerfausts, which are of considerable interest. Here are the figures:

Total number of kill claims on the Eastern Front for February of 1944: 1219
Of those:
  • Tanks: 397
  • Tank destroyers (StuG and Marder): 355
  • AT guns: 291
  • Other (artillery, mines, etc): 114
  • Handheld anti-tank weapons: 62
    • Panzerfaust: 35
    • Panzerschreck: 19
    • Haft H3: 5
    • Teller mines: 2
    • Hand grenades:1
For March, data is only given for hand-held anti-tank weapons. 
Total: 105
  • Panzerfaust: 47
  • Panzerschreck: 23
  • Teller mines: 18
  • Haft H3: 13
  • Hand grenades: 3
  • Flare gun: 1
In February, the Panzerfaust and Panzerschreck are responsible for the vast majority (87%) of infantry kill claims, but a very small number of overall claims (4%). This is consistent with Soviet reports that only 3% of tanks of the 1st Belorussian Front were destroyed by these weapons

Another interesting note is that the magnetic Haft H3 mines are responsible for a tiny amount of casualties, making one question why the Germans bothered developing anti-magnetic mine Zimmert coating when their mines were so ineffective even against Zimmerit-free vehicles.

A year later, during the Budapest Offensive Operation, the effectiveness of Panzerfausts was, shall we say, greatly reduced:

"According to data from the Armoured and Motorized Forces of the 2nd Ukrainian Front, in February of 1945, out of 160 total tanks and SPGs damaged in combat, two were damaged by Panzerfausts, composing a total of 0.5-0.6% of total losses. The damage caused by Panzerfausts was as follows:
  • One T-34 tank had its track broken from 50 meters.
  • One T-34 tank was hit in the side armour plate, resulting in only a crack. Range: 50 meters"

Monday, 13 October 2014

Cheating at Statistics 8: Seeing Things

Many engagements involving Tigers have been elevated to legendary status, and many more have been forgotten. It is a shame, as it can be difficult to reassemble bits and pieces of engagements that are rather interesting. For instance, documents of the 7th Guards Independent Heavy Tank Regiment record a somewhat unusual vehicle, the KV-85, engaging in battle with Tigers. Here is their account of the battle (from M. Baryatinskiy, Heavy KV Tank in Battle, Moscow, 2007):

"According to orders from the HQ of the 17th Corps, remaining 5 tanks and SPGs (3 KV-85 tanks and 2 SU-122 SPGs) set up for a defense of the Telman farm to deflect enemy attacks towards Rososhe, the Kommunar farm and Bolshevik farm at 7:00 on January 28th, 1944. 50 infantrymen and 2 AT guns filled the defensive perimeter. A concentration of enemy tanks was spotted south of Rososhe. At 11:30, 12 enemy T-6 tanks and 13 medium and small tanks attacked the Telman farm from the south, with infantry cover.

From effective positions, cover from buildings and haystacks, our tanks and SPGs let the enemy approach to straight shot range and opened fire, upsetting the enemy's formation and knocking out 6 tanks (3 of them Tigers), destroying up to a platoon of infantry. Senior Lieutenant Kuleshov's KV-85 was selected to destroy the German infantry that has broken though. With fire and tracks, he carried out his orders. At 13:00, German forces that did not wish to attack the Soviets head on flanked the Telman farm and encircled the Soviet group.

The battle of our tanks when surrounded by a numerically superior force shows exceptional skill and heroism of our tankers. The tank group (3 KV-85 and 2 SU-122), commanded by the company commander, Guards Senior Lieutenant Podust, defended the farm, while at the same time not letting the Germans move their forces elsewhere. Tanks frequently moved positions and fired on German tanks, SU-122s entered open terrain and shot up infantry on APCs heading for Ilyintsy, preventing the Germans from maneuvering freely and allowing elements of the 17th Infantry Corps to withdraw. Tanks continued fighting until 19:30, even though there was no longer any infantry at the farm.

Maneuvers and effective use of cover ensured heavy damage to enemy forces with very light casualties (2 wounded). On January 28th, 1944, 5 Tiger tanks were destroyed or knocked out, as well as 5 PzIVs, 3 PzIIIs, 7 APCs, 6 AT guns, 4 machinegun nests, 28 horsecarts, and up to 3 platoons of infantry.

At 20:00, the tank group attempted a breakthrough, and at 22:00, after battle, broke out to Soviet positions, having lost one SU-122."

Well, that was heroic and all, but I am a sceptic, and I must first at least establish that such a battle took place. Flipping through my good friend Tigers in Combat, we will find no mention of Telman farms or Rososhe, but there is only one mention of any SU-122s in January of 1944, in the journal of the Feldherrnhalle battalion, mentioning the name "Oratoff". Luckily for us, Oratoff still exists on the map, a city near Vinnitsa. A prior mention of "five enemy tank corps spotted 100 kilometers north of Winniza" tells us we're in the right place. Time to pull out a map!


Vinnitsa is that blob near the lower center of the map, and what do you know, two arrows clash right on top of Oratoff (sadly not pictured on the map), the top one being the 1st Tank Army, the unit that the 7th Guards were fighting with. Ladies and Gentlemen, we have our battle. We also see the German tendency to grossly overestimate Soviet forces: despite reporting five tank corps north of Vinnitsa, the Soviet map only shows the 3rd Guards Tank Army there, home to two tank corps. Even if you include the 1st Tank Army to the north-east, that is only one additional tank corps. 

All right, we figured out where we are, time to take a look at the German account of the battle. The account is rather sparse:

"28 January 1944: Breakthrough to the Oratoff railway station."

Well that really doesn't give us interesting to look at. Thankfully, the next few lines offer something better:

"29 January 1944: Fighting at Oratoff. Abortive recovery attempt of disabled Tigers 112 and 132.
Total tanks: 66. Within five days, 267 tanks are knocked out with a loss of 3 Tigers and 4 Panthers."

Very good, we are getting somewhere! Time to determine how accurately the sides counted their kills.

The Soviet count is easy. Let' start with the Tigers. The Soviets claim five knocked out or damaged, the Germans give three outright losses and 2 that they were able to recover (as we have determined previously, the Germans do not count vehicles that can be recovered towards their losses). Everything adds up here. The Tiger battalion doesn't own up to losing any "lesser" tanks, so those probably came from the German 3rd tank division, also present on the Soviet map, whose records I unfortunately do not have. Similarly, Soviet records don't claim the 4 Panthers lost, so perhaps they fell to another part of the 1st Tank Army.

The German claim is much more bold: 267 tanks knocked out! That is a rather significant force. Like in Korner's case, let's count how many tanks the 1st Tank Army had at its disposal: the 6th Tank Corps (3 tank brigades, 65 tanks each for 191 total), 112th Tank Brigade (another 21 tanks), and four tank regiments (also 21 tanks apiece, 84 total) for a grand total of 300 tanks. But that's only a maximum number of available tanks, how many tanks did the Soviets actually have in this area? Luckily for us, the 1st Tank Army has a rather detailed memoir, The Combat Path of the First Tank Army and Its Heroes. Volume 3 describes the relevant time period, where Guards Colonel Koltunov writes on page 12: "...on all sections of the front, our units, having one fifth to one sixth of their numbers remaining at best, deflected furious attacks of large enemy groups of tanks and infantry, supported by aircraft."

A fifth or sixth of maximum capacity at best! That puts the Soviet forces at an optimistic estimate of 50-60 vehicles which makes sense, given the 7th Guards' poorly equipped state (3 KV-85s out of a tank regiment's 21, plus a couple of SU-122s, likely folded in from an SPG unit). Even assuming that the 1st Tank Army has suffered no casualties at all in its month-long offensive and all of its losses came from the attacking Tigers, there is still quite a bit of overclaim. 

Sunday, 12 October 2014

Remote Control

"February 17th, 1935
To the director of the Institute of GlavExProm Telemechanics and Communications and head of the Technical Institute

Minutes of the meeting on the topic of telemechanization of T-26 and T-46 tanks.

Present:
  • Director of the GlavExProm telemechanical institute, comrade Suchkov
  • Chief of the Technical Institute, comrade Mileynovskiy
  • Chief of the 2nd department of the Technical Institute, comrade Belov
  • Director of the Experimental Kirov Factory, comrade Barykov
Summary:
  1. The GlavExProm ITC is considered the head organization of telemechanization of the T-26 and T-46 tanks.
  2. The main designer of the T-26 and T-46 vehicles and the driver and commander's control panels is the Experimental Kirov Factory.
  3. ITC promises to supply Kirov Factory with the necessary amount of workers for the duration of the development and to locally produce all electromechanical components.
  4. Kirov Factory and ITS promise to complete the telemechanization project by July 1st, 1935. 
  5. The cost of the T-26 project is 100,000 rubles and the T-46 is 120,000 rubles.
  6. The cost and time for production will be determined after the blueprints are completed.
Suchkov
Milenovskiy
Belov
Barykov"

Saturday, 11 October 2014

Hatches

A number of sources, both memoirs and secondary sources founded on the memoirs, write that Soviet tank crewmen did not look out of their tanks through the hatches, which reduced their visibility on the battlefield, some going as far as claiming that it was actually forbidden. But was it? The Soviet 1944 armoured vehicle manual certainly doesn't say so. In fact, what it says is the opposite.

"154. In combat conditions, all crew members and observation posts observe the battlefield. Platoon commanders operating on flanks should pay special attention to open flanks. Before contact with the enemy is made, observation is to be performed from open hatches. The observers report anything that is observed to their commander."

"250. The crew must constantly and carefully observe the battlefield, look for landmarks, seek targets, and keep them in sight, reporting them to the tank commander. If the target is lost, it is permissable to carefully observe through an open hatch. The crew must pay attention to the platoon commander's vehicle in battle and follow his signals."

This manual is applicable to tanks (medium, heavy, and special), armoured cars (light and medium), SPGs, APCs, and special vehicles, so nearly any crew would have read it and would be obliged to follow it.

Soviet memoirs also contain instances of commanders remaining unbuttoned even during battle.
Nikonov, Ivan Sergeevich: "As soon as it dawned, the Germans attacked. I saw out of my hatch how the infantry was retreating, pushing a 45-er. Tanks appeared. I ordered my crew to let them come within 500-600 meters. The battle started, we were shooting at them, they were shooting at us. ...
I commanded the battle while out of the hatch up to my belt. I never ducked down and shut myself in my tank. What is the commander's mission? Ready the tank before battle, pick the correct target in battle, correctly judge the situation, correct the fire. Fortifications in front of me were pockmarked with shells that fell too close. A few shells flew past me..."

Ivanitskiy, Ivan Sidorovich: "Did you open hatches when you attacked?" "Of course, cracked them open by about the size of your palm. It's hard to see through the periscope, you open the hatch to get the best visibility. It's dangerous, of course. A fragment can fly in, but you can see where you're going and what's happening around you."

Friday, 10 October 2014

"USSR" Armour

"Description of an invention titled "Armour Type USSR"

The armour plate (1, 2) is covered in pits (3), that have a special shape. Inside each pit, there is a charge with a detonator (5). Most bullets that hit the armour will hit inside the pit, as any object will obey the laws of least resistance and ricochet off the walls into the depth of the pit. The pits will have a shape slightly smaller than the bullet, so when the bullet hits, it will plug the pit.

The bullet (4) will hit the detonator with its tip, which will detonate the charge. The resulting gas expansion will slow down the bullet and not let it penetrate the armour.

December 1st
Astrakhan

Bruskin."



Figure I shows the front view of Bruskin's armour plate, figure II shows the side view, of what happens when a shell hits the armour. Obviously this idea needs some work before implementation, but it's definitely ahead of its time. Work on reactive armour would not start for many years after this patent application was submitted.