World of Tanks: Today in History: Liberation of Odessa

The goal of the Odessa Offensive Operation that took place between March 26th and April 14th 1944 was to defeat the 6th German and 3rd Romanian armies, liberate Odessa and the North-West coast of the Black Sea, and reach the border between the USSR and Romania.

The preparation of the operation was difficult due to poor conditions of the roads, muddy from spring rains. Supplies could only be delivered by tracked tractors and all terrain vehicles. Furthermore, the planning was done without stopping the offensive, which also caused problems.

The Odessa Operation began on March 27th, when the forces of the 3rd Ukrainian Front widened their footholds on the South Bug. By March 28th, the foodholds deepened to 25 kilometers. In order to continue the success, the mechanized cavalry of General Pliev and 23rd Tank Corps of General Akhmanov were sent in.

The penetration of the defensive lines at the flanks of the German-Romanian group forced them to retreat behind the Dniester river. The mechanized cavalry of the 37th Army cut off their retreat. Some amount of enemy forces broke through in the direction of Tiraspol, but many were encircled.

On April 9th, Soviet forces began advancing, and entered the northern outskirts of Odessa. After a night assault, with the cooperation from resistance and partisans, the city was fully liberated. The Soviet units continued their advance until the Dniestr, where they captured footholds and secured a start of an important offensive against the enemy armies.

Original article available here.

Soviet Tanks in the Far East

Here are the tanks the Red Army had available in the Far East for war with Japan as of August 5th, 1945. As you can see, some of these tanks have been there for quite a while, as they are downright antiques. As per Soviet tradition, tanks that require light repairs (repairs that can be completed by the strength of the tank unit) are included in the "functional" column.

Vehicle	In possession	Functional	Med. Repairs	Maj. Repairs	Irreparable
T-34	1899	1794	32	70	3
M4-A2	250	250	-	-	-
BT-7	1030	797	41	179	13
T-26	1461	1272	33	122	34
KV	77	47	5	23	2
Valentine	81	78	3	-	-
T-60/70	46	14	-	28	4
BT-5	190	101	-	23	66
T-38	325	304	20	1	-
Tankettes	52	52	-	-	-
IS	19	6	1	12	-
T-27	56	56	-	-	-
T-37	52	52	-	-	-
M3 light	1	-	1	-	-
M3 medium	1	-	1	-	-
Various	5	5	-	-	-
Total tanks	5548	4841	137	455	125
ISU-152	197	188	1	8	-
ISU-122	1	1	-	-	-
SU-100	262	261	1	-	-
SU-76	952	944	9	-	-
SU-152	11	-	-	11	-
SU-85	6	1	-	5	-
SU-122	6	2	-	3	1
Total SPGs	1422	1393	11	28	1
Total	6980	6234	148	483	126

The small number of IS tanks available casts doubt on the assertion that IS-3 tanks were present in the theater.

Source: Russian Archives: Soviet-Japanese War of 1945: history of a military-political struggle between two nations. Documents and materials. Volume 2, table 18. Moscow, Terra, 1997, page 339.

Panther Trials

The Panther tank made its debut in the Battle of Kursk. Naturally, the Soviets captured some and subjected one of them to trials. A comparison with the newest Soviet heavy tank at the time, the IS-2 model 1943, is made, as well as a less detailed comparison with PzIII, PzIV and Tiger tanks.

Overall view of the Panther tank.

Photo #1. View from the right, at an angle.

Photo #2. View from the front.

"Amount and conditions of trials.

The Panther tank #824, captured on July 17th, 1943 by General [illegible, likely Krivoshein]'s forces near the Novoselovka village in the Kursk region, was subjected to trials. Before the start of the trials, the tank travelled 452 km (from its speedometer). The tank travelled 220 km during trials between August 8th and October 5th, 1943, with repaired components, including:

• asphalt highway: 58 km
• dirt roads: 162 km

The engine worked for 13.9 hours.

During these trials, the tank broke down three times, and had to be towed back to the proving grounds. In addition to the above distance, the tank travelled 36 km while being towed.

The tank was fueled with aircraft gasoline KB-70. The oil system was filled with MK aircraft oil. The transmission remained lubricated with German grease. The suspension was lubricated with grease. 

The road conditions were as follows:

• Highway: paved with asphalt, Moscow-Minsk highway. The road is 12 meters wide and has grades up to 5 degrees. Movement along the highway was not fast.
• Dirt road: forest and field, wide, with a large amount of deep ditches, grades up to 10 degrees. The roads are muddy in places. External temperature was between 8-17 degrees Celsius, no precipitation. 

Mobility trials were conducted with the tank in travel position, without ammunition.

Gunnery trials

The 75 mm gun was tested by shooting from a stationary position at one and two targets at 1000 meters in order to evaluate accuracy, rate of fire, and convenience of working in the fighting compartment while shooting.

Special trials were conducted to determine the penetration and maximum effective range for the AP and subcaliber AP shells of the Panther and Ferdinand.

The evaluation of precision was done by observing the explosions from HE shells and examining damage to armour plates from AP shells.

The rate of fire was recorded by groups of 5 shots, timed from the "fire" command to the last shell.

A lack of 75 mm shells limited the amount of possible armament trials.

Results of mobility trials

Maximum speed

The maximum speed of the tank was determined on a straight stretch of road between the 42nd and 43rd kilometer of the Moscow-Minsk highway by two trials in opposite directions. The maximum speed attained was 50 kph. The tank drove in 7th gear.

Agility

Trials determined that the planetary mechanism lets the tank turn well. Due to a hydraulic servo, the tank is easy to control. 

The Panther's turning mechanism does not have the properties of a differential mechanism, which increases the tank's stability on straightaways and increases its off-road performance. This gives the tank an advantage over the Mk-IV Churchill and PzVI Tiger. In practice, it was impossible to turn the tank in place. Due to the difference of resistance on either side, the tank could only turn by locking one track and letting the track from the opposite side of the turn go forward or backward. Turning in place can only be done with equivalent resistance on both tracks, which in practice can be done very rarely.

Conclusions

1. The Panther tank, widely used by the German army since summer of 1943, is a new type of heavy tank, vastly different from other heavy tanks in tactical purpose. The difference is in the use of Panther tanks as tank destroyers, and not as breakthrough tanks. This is indicated by thick front armour and a powerful gun, but poor side, rear, and turret armour.

The following are tactical characteristics of the Panther tank compared to the IS-122 tank, which has a more powerful gun than the Panther.

Characteristic	Panther tank (Germany)	IS-122 tank (USSR)
Combat mass (tons)	45	Up to 46
Crew	5	4
Dimensions
Length (with gun)	8850	9830
Length (without gun)	6900	6770
Width	3430	3070
Height	2910	2730
Clearance	480	470
Turret ring diameter (mm)	1650	1800
Ground pressure (kg/cm^2)	0.84	0.81
Armour thickness (mm)
Front	85-65	120
Side	40	90
Rear	40	60
Turret	100-45	100 (cast)
Roof and bottom	27	30-20
Amount of guns and caliber	1 75 mm	1 122 mm
Gun length in calibers	67.25	47
Muzzle velocity (m/sec)	1000	790
Machineguns	2 7.92 mm	3 7.62 mm
Ammunition	80 rounds	28 rounds
Observation devices
Periscopic sights	0	1
Telescopic sights	1	0
Periscopes	4	4
Observation slits with armoured glass	7	7
Observation slits with armoured cover	1	0
Engine	Gasoline	Diesel
hp/ton	14.4-15.55	11.3

2. The Panther tank has a powerful 75 mm long barreled gun. Its shells have high penetration, achieved through increasing the propellant, higher muzzle velocity (1000 m/s) and good shell toughness.

The new model 1942 subcaliber shell allows for aimed fire at up to 2000 m, unlike the old subcaliber shell that was only effective at 500-600 meters.

The convenient position of aiming mechanisms, an electric firing mechanism, and a high quality binocular (refracting) sight, high accuracy and rate of fire (6-8 RPM) are achieved. 

The ammunition rack is positioned inconveniently. Only a part of the ammunition is stored in the turret, and the rest requires aid from other crew members to load. 

The IS-122 tank possesses a more powerful D-25 122 mm gun. The two-piece shell and screw breech lower the rate of fire to 1.5-2 RPM. The higher caliber reduces the ammunition capacity to 28 rounds.

3. The armour of the Panther tank is much thicker in the front than on the sides. This is achieved by a high slope of the front plates and a 2:1 ratio of thickness between the front and side plates. The Panther has a new hull shape for heavy tanks, inspired by the domestic T-34 medium tank. The sloped armour allows for the use of thinner armour while increasing the hull's resistance to shells. 60-80 mm is not a lot of armour for a heavy tank, but penetrating it is difficult due to the chance of ricochet.

The IS-122 is significantly superior to the Panther tank in its side, rear, and turret armour. The side armour of the IS-122 tank is only slightly less than its front armour, unlike the Panther, which makes the IS-122 tank more tactically adaptable. The Panther uses advantages of sloped armour more fully in the front than the IS-122.

4. The Panther no longer has a large amount of observation hatches like on the PzIII and PzIV, in order to increase protection. The Panther is equivalent to the IS-122 in observation quality. The commander and driver can see well. The visibility of the radio operator is satisfactory. The lack of observation devices for the gunner and loader reduce the observation quality of the Panther compared to the PzIII and PzIV.

5. The use of a gasoline engine on the Panther tank reduces its usage characteristics compared to the IS-122 tank, which has a diesel engine. Despite the higher hp/ton, the Panther has little advantage over the IS-122 in speed. The fuel economy of the Panther tank is greatly inferior to the IS-122 tank. The Panther has identical operational range as the IS-122 when using internal gas tanks, and 50-60% less if external fuel tanks are used.

The trials established that KB-70 aircraft gasoline works in Panther tanks.

6. The reliability, overall design and technological level of the components and assemblies of the Panther is less than that of the PzIII and PzIV. 

The least reliable component is the HL 230 engine that is not finished in either design or implementation. This was confirmed by constant breakdowns during trials (tearing of the valve pins, etc). The fan drive is another unreliable component, due to rapid wear on the drive's gears. The tank's suspension and transmission worked well during trials and did not break down.

Evaluation of the design

Armour

1. The Panther tank is armoured with rolled homogeneous chrome-nickel-molybdenum steel, cast chrome-molybdenum steel. The armour screens are made from low carbon (less than 0.1%) pot metal. Compared to Tiger, PzIII and PzIV tanks, the Panther's armour contains more nickel up to 0.6%-1.7%
   The armour is harder on the outside than the inside, which indicates surface hardening or cementing. 
2. The use of interlocking plates increases the toughness of the welding seams.
3. The Panther's size is a disadvantage. It is longer than the IS-122 by 130 mm, wider by 360 mm, and higher by 180 mm.

Engine

1. The use of a gasoline engine can only be explained by the specifics of the German fuel economy, which relies on synthetic gasoline.
2. The Maybach HL 230 engine is a special tank engine designed with the requirements of a tank in mind.
3. The engine is compact in design. Its installation gives good access to components that require periodic maintenance or can break down.
4. The installation or removal of the tank's engine is relatively simple, which is achieved by:
1. The drive shaft connection with the transmission, which removes the necessity for precise adjustments.
2. Two rubber pads suspending the engine.
3. All oil system components (including the tank and radiator) are mounted on the engine.
4. The accessibility of most pipes and controls is satisfactory.
5. The high power of the engine is achieved through high filling coefficient, compression, RPM, and compact combustion chamber.
   The high filling coefficient is achieved through a very large exhaust valve,  aerodynamic head, short and gradual exhaust channels, lack of preliminary heating of the fuel mix, and a separate carburettor for each of the 3 cylinders, with a separate power section which is enabled only when maximum power is close to being reached.
6. The engine has good starting properties due to special starting sections of the carburettors and  magneto acceleration clutches. In low temperatures, the engine is easier to start due to:
1. Injection of startup fuel into sucking collectors from a separate tank.
2. Pumping hot water through the coolant system from an external heater or by heating up the coolant system with a blow torch along with the external heater, which simultaneously heats up the oil due to the oil-water radiator.
7. The engine compartment fire safety is increased by:
1. Isolation of the engine compartment from coolant system airflow.
2. Screening of the exhaust pipes, special airflow, and increased tightness of all connections.
3. Positioning of air filters directly above the carburettors, which reduces the possibility of a back-fire.
4. Secure insulation of all electrical elements.
5. Careful design of all oil reservoirs and connectors to prevent oil and fuel from leaking out onto the compartment floor.
6. Automatic fire extinguishers in the engine compartment.

Transmission

1. The planetary mechanism is of interest. It is a continuation of the planetary mechanism used on the Tiger tank, which is evidence that the Panther tank was produced after.
2. The layout and design of the turning mechanism are simpler than that found on the Tiger tank, retaining all the advantages of this design over other mechanisms.
3. The turning mechanism of the Panther and Tiger tanks provides a stiff connection with the tank's tracks when the tank turns. This allows the use of power from the drive wheel of the lagging track, and passing it on to the leading track (power regeneration effect).
   Combined with the reduced loss of power from the turning mechanism, this significantly reduces the engine power needed to turn and allows the tank to turn well.
4. Advantages of the Panther's turning mechanism over the Tiger's turning mechanism include the lack of a differential mechanism, which leads to more stable straight line movement and higher off-road performance. 
5. The turning mechanism of the Panther tank only exhibits differential properties when turning in place, with the gearbox in neutral position. Turning the tank in place can only be done when the resistance on both tracks is identical. Due to the differences in resistance, turning is usually achieved around the track with the higher resistance.
6. The hydraulic servo makes steering the tank easy. It is necessary to evaluate the servo's performance in the winter.
7. The main friction clutch, gearbox, and turning mechanism are very compact. The assembly takes up relatively little space in the hull.
8. The method of lubrication of the gearbox, turning mechanism and final drive gears with a stream of oil aimed at the contact point deserves investigation.

Suspension

1. The most interesting component of the suspension is the design of the torsion bar suspension, with two parallel torsion bars for each road wheel. This design allowed the Germans to achieve a soft suspension, while retaining robustness of the torsion bars.
2. All suspension elements are well designed.
3. The suspension requires little maintenance. The use of a central lubrication through oilers grouped in two places deserves attention.

Electrical equipment

1. The Panther's electric network contains a simple and reliable automatic fire extinguisher, as well as a simple and reliable electric firing mechanism for the gun.
2. A disadvantage of the electric network is the large and complicated rotary connection."

CAMD RF 38-11355-2638

AT-1 Development

"The AT-1 hull differs from the hull of the T-26, it is slightly lengthened. The added length allows moving back the gun system back, along with the sight. It is possible to place the sight further back for indirect fire. 

Leave the PTK on the left and the simplified PTK on the right in the prototype and the trial batch. If it is not possible to satisfactorily position the dials and sight in such a way that it does not impede the driver, it is acceptable to move the driver to the right. Complete the revision of mechanisms and check them by June 1st.

In order for mass production to begin in 1939, the commission considers that the prototype with the production L-10 gun should be produced in metal no later than July 15th. The gun mount for the L-10 should be provided by the Kirov factory no later than July 1st.

Overall, the commission notes the lack of a rotating turret, which lowers the value of the vehicle as an artillery tank. In parallel with development of the AT-1, work on equipping the T-26 with the 76 mm gun in the BT fully rotating turret.

Allow factory #174 to produce blueprints with the driver on the right and use them for the trial batch of 3 vehicles."

RGVA 31811-2-880

"A trial installation of the L-10 gun in the AT-1 vehicle shows that, without a radical hull redesign, it is not possible to achieve adequate placement of the driver and gun crew. 

Taking into account that, due to its limited gun traverse, the AT-1 is unsuitable for cooperation with tank units, and can mainly only be used for fire from closed positions, I ask for your permission to cease work on the AT-1 vehicle.

Further effort should be directed to mount the 76 mm gun on the T-26 in a fully rotating turret from the BT-7, which, perhaps, will allow for less changes to the stock T-26 vehicle."

RGVA 31811-2-880

The Problem of Claims

I have written a number of articles exposing inaccurate kill claims, so it's always nice when someone points out that their own claims may be just a little bit overestimated.

Harsh Words

Communication is a difficult task. You have to balance secrecy with convenience, and, when that doesn't work out, professionalism with harsh language. Let's watch.

"Malinin here.

Malandin here.
We just received a resolution from the commander, familiarize yourself with it. Honestly, how did you managed to think of such a damned stupid thing and send a ciphertext instead of a flash about tanks? The commander ordered me to swear at you profusely for this disgrace. So you do not do this again, report concisely where the enemy tanks are, so a decision can be made with this information, such as help with aircraft and the 21 tanks from the 22nd Tank Brigade that the commander temporarily assigned to combat breakthroughs. I await the sitrep, briefly, where are enemy tanks?

Colonel Ryzhikov here. Malinin has strep throat and the doctors recommend that he should not go outside.

Closer to current matters, you can tell Malinin what happened later.

Yes sir.

Report immediately.

Up to 80-100 tanks advanced on Fedosino

Where are the tanks? I don't need the full history, where are the tanks right now?

The tanks are in Ostashino. Everyone stationed there is fighting them.
Lieutenant-General Rokossovskiy here. Who asked for me?

Comrade Rokosovskiy, Malandin here. The commander is very displeased that Malinin sent a ciphertext about the breakthrough, and this caused the message to be late by 3 hours. He ordered me to swear profusely at him. Tell him that. The commander wants to know where the tanks are so that they can be attacked with aviation and our tanks. Second, what did you counter the tanks with?

Hello, comrade Malandin. The battle is at Ostashevo. I threw in what I had. I gathered a battalion of infantry from various units, and two batteries from our AT gun Guards regiment. That is all I could transfer there. There is nothing else I can move from the front, as the Lithuanian group is displaying activity, which is likely to develop into an offensive in the morning. We are doing what we can and will not leave without fierce battle.
I would ask for my HQ to be moved to the Teryaeva Sloboda monastery north of Volokolamsk, and the second echelon moved to Pokrovskoye to ensure that I have communication with my forces for as long as possible, as the communication line and supply line will go through the center of the army. I received reports from my left flank that they are fighting well, and retreated only when all of their artillery was destroyed by the enemy. That is all.

The commander allowed for the 21 delayed tanks to enter your command for combat with the breakthrough. The aircraft have orders to bomb tanks at night. Mark your region with hidden fires. I will go report to the commander and pass on his decision.

No tanks were delayed here. Everything the brigade had moved on to Volokolamsk, without leaving individual tanks. We did not halt any tanks for subsequent movements. This is all. I will wait."
CAMD RF 208-2511-140

KV-9 Production

"To the deputy People's Commissar of Tank Production of the USSR, Major-General of Technical Forces, comrade Kotin
Chair of the Technical Council of the Council of People's Commissars, comrade Satel
Director of the Kirov factory, comrade Mahonin
Director of Kalinin factory #8, comrade Fratkin
Regional GAU KA engineer at factory #8, Engineer-Colonel comrade Kasheyev
Regional GABTU BTU engineer at the Kirov factory, Engineer-Lieutenant-Colonel comrade Kozyrev

On the issue of a trial production run of KV-9 tanks.

Trials of the KV-9 tank armed with a 122 mm U-11 howitzer ended in March of this year.

In August of this year, continuing this work, factory #8 produced two U-11 howitzers with corrections according to proving grounds trials, and Kirov factory (#100) made corrections to the KV-9 tank according to the conclusions of the commission.

I ask for your orders to assemble a trial run of KV-9 tanks with U-11 howitzers for battlefield trials. For this, the following is necessary:

• Factory #8: produce a lightened pipe guard for all howitzers according to the blueprints provided to the Artkom and send them to the Kirov factory (Chelyabinsk).
• Factory #69: develop blueprints for scope markings for the TMFD and PT-4 sights for a gun with the ballistics of the U-11 122 mm howitzer, produce three of each, and immediately send them to the military representative at the Kirov factory (Chelyabinsk).
• Kirov factory: equip the fighting compartment in the old type of turret with a fighting compartment, ammunition rack, a commander's cupola of the KV-1S type (forward and to the right). In order to lighten the tank to 45 tons, mount the turret on a lighter KV-1S hull.

I ask you to inform me of your orders and estimated completion times.

Deputy GAU KA Chief and Artkom Chair, Major-General of Artillery, Hohlov

Deputy GABTU KA Chief, Major-General of Tank Forces, Korobkov

October 23rd, 1942"

CAMD RF 81-12038-32

Upgrade

"To the Chief of the Red Army GBTU TU, Engineer-Colonel comrade Blagonravov

I report on the status of the Object 701 as of September 17th, 1944.

Vehicle #1 (previously examined  by the government commission) is completely disassembled. The hull was used to mount new components, which implement suggestions from the commission.

The aforementioned vehicle has the following mounted: suspension, side reductors, engine, fan motor. The planetary transmission is currently being assembled at mechanical plant #2.

After the end of assembly, the vehicle will be subjected to factory trials with the goal of determining the reliability of components and the possibility of their installation on further objects that will be examined by the government commission.

Senior military representative of the Red Army GBTU TU, Engineer-Major Lelyakov"
CAMD RF 38-11355-2511

You What, Mate?

Sometimes, people make mistakes. Thankfully, there are people there to catch them. For example, in this report on the ISU-152-1. See if you can find it.

In this case, the explanation is easy. You can see the dried glue around the photograph. Evidently, a number of pictures fell out, and were replaced by someone in a little too much of a hurry.

Firewall

"P.G. Solovyev's proposal is for a method of protecting a car when it is surrounded by enemy infantry. Solovyev proposes putting a thin metallic pipe around the vehicle, with small holes, and connect it with the car's gas tank. When compressed air is pumped into the tank, the gasoline will spray out of the holes. If ignited, it will form a fire wall around the car, protecting it from capture.

The technical committee of my Directorate considered this proposal and its conclusions written by the Chief of the Automotive Military School from September 19th of this year #5591, recorded in the journal on September 21st under #909, and came to the conclusion that, due to a small gasoline tank, and small size of the ignited gasoline streams, Solovyev's method of protecting the vehicle has no practical applications.

Signed, acting Chief of the Main Military-Technical Directorate, Engineer-General Aleksandrov
TK Matters Director, Military Engineer, Major-General Svizdinskiy
September 22nd, 1915."

And, the ever so polite response to the creator:

"...The method you propose does not deserve practical application. It is dangerous to the vehicle itself. The effect from sprinkling gasoline will be negligible. Additionally, the vehicle may be left without gasoline to run on."
RGVIA 803-1-1828