Re. JS-2 and JS/3
During testing, JS-2 broke through the frontal armor of a Panther from the distance of 1500 meters but then the shell having excess of energy pierced the transmission, combat compartment, engine, and even after that the shell energy was so strong that it tore off rear hull armor plate along the line of welding joints (seams) and threw it away for few meters. But JS-2 (weight 46 tons) was in the same weight category as a Panther (45 tons). But Panther’s shell didn’t penetrate JS-2’s frontal armor from 1500 meters. Shells of a Tiger (weight 56 tons) and Tiger-II (weight 67 tons) didn’t penetrate JS-2 from 1500 meters distance as well. But JS-2 penetrated their (Tiger and Tiger II) frontal armor from 1500 meters. Apart from JS-2, Soviet Army placed in service JS-3. JS-3 was shown to the Allies during a parade in Berlin in 1945. JS-3 served for a long time as a golden sample for numerous foreign replications/imitations. JS-3 was even esthetically beautiful. Even after 50 years, no tank in the world could be compared with JS-3 in elegance of shapes.
Let’s remember the main thing: while comparing Soviet and German tanks of the World War II, a heavier German tanks were not a more powerful ones compared to less heavy Soviet tanks. Not at all. Soviet tanks had a rational layout (engine and transmission in the rear and no cardan shaft). German, US, British and Japanese tanks had irrational tank layout (transmission in the front and engine in the rear). If one man has a weight of 150 kg it does not mean that he is stronger than a man whose weight is 80 kg. A man with greater weight can simply carry excessive fat, like German, British, US and Japanese tanks carried excessive additional armor protecting unnecessary volumes.
First German heavy panzers were tested only in the end of August of 1942. These were good and powerful tanks. By some parameters German designers managed to catch up and even outrun Russian KV and T-34. But not by all parameters. According to Sun-Tsi, Chingis-Khan, Napoleon, Rokossovsky, Guderian, Brussilov, Vatutin and others only movement, speed and agility brings a victory. By all parameters that measured agility of tank such as speed, ability of a tank to move cross-country, mobility, maneuverability, range German tank designers failed to catch up with T-34 and KV.
Besides it, Russian tanks had a powerful, economic and less fire prone diesel engine, which worked equally well in frosty winter and hot summer. In Germany, country of Rudolf Diesel, such tank engines didn’t exist and tank designers had to install gasoline ones. Soviet tank designers also didn’t rest on their laurels. They were modernizing KV & T-34 and were preparing for production JS (Joseph Stalin) tanks, which almost by all parameters remain a dream for designers and generals of other countries till the end of the war.
German tank designers having at their disposal captured KV and T-34 failed to understand the main “secret” of Russian tank designers. German designers, even having in front of them samples, did not understand the most important thing and repeated the same mistake: an engine in the rear and transmission and power unit in the front. The result: Army ordered a tank of 45 tons weight as a KV but got a Tiger of 57 tons weight. New problem was how to move such a weight in the cross-country terrain?
Larger diameter of supporting wheels easier a tank goes through obstacles. Therefore it is in the interest of a designer to make supporting wheels with the bigger diameter. On the other hand, in order to improve cross-country ability and mobility of a tank, a designer is interested to increase number of footholds and in other words to increase the number of supporting wheels. And in order to be able to achieve that, to make the wheels with lesser diameter. Designer has to search the Golden Middle between these two opposite intentions.
From each side it was possible to place 4-5 supporting wheels with big diameter. If Tiger’s weight was normal that would be enough. But weight was abnormal. Bigger number of supporting wheels was required. And then German designers decided to have three rows of wheels from each side… They made wheels thin as a plate and put a tank on the rows of “plates” placed in the “chess order”: three rows from one side and three rows from the other side. It seemed to be a good decision. Supporting wheels had a big diameter and while moving cross-country strikes were taken by eight footholds of “plates” from each side… But everything has its price. “Plates” were crushing (squeezing) after two hours of movement in cross-country terrain. A Panther was also put on “plates”. And they were also crushing (squeezing). Let’s close our eyes and imagine: a Panzer Abteilung carried out two hours marsh and stop to change tracks and change supporting wheels… What a hassle! It’s good to do in the training but how to do that in a tank battle at Prokhorovka? Tiger’s tracks were damn wide and heavy. Designers didn’t hold a tank weight and that’s why very wide tracks were required. Another trouble was that very rare bridge could sustain a tank of such a weight. Floating bridges were collapsing under Tigers. A Tiger could make a forced crossing of a river only under Railroad bridges. First they had to capture a railroad bridge and on the other side (bank) to capture (beat off) a station with the high platform. Then to find on their side a station with a high platform, move there Tigers, load them in railroad cars, transport them across the river and unload them on the other station with a high platform… Simple exercise? Not really. The problem was that a Tiger on the wide tracks could not be placed on the railroad platform. That’s why a solution: “wide” and “narrow” tracks were designed for Tigers. It was moving on wide tracks and narrow ones were carried after him. These panzers were crossing rivers in a combat in the following way: a tank was driven to a station with a high railroad platform. A heavy truck carrying a “narrow” Tiger’s track was driven to the same station as well. And one more truck with another “narrow” Tiger’s track. These tracks even being “narrow” ones could not be taken by one truck. A third truck with a crane: even being “narrow” Tiger’s tracks could not be loaded/unloaded manually. Then simple. “Wide” tracks and one row of “plates” were removed from a Tiger and “narrow” tracks were put on. Then carefully, a tank was driven on a platform trying not to move on a soft ground to avoid getting stuck. Then loaded “wide” tracks on trucks, moved them onto platforms, crossed a river, transported a railroad car to the next station, which German infantry was able to beat off without tank support. Then tanks had to be unloaded and change “narrow” tracks for “wide” ones. Again, a Tiger was fighting and three trucks with a crane were nearby. If there would be a river of ten meters width how to cross it? Once again, they had to have two stations, a railroad bridge and repeat everything from the very beginning. In 1941 Hitler did not have these wonder-machines. All these existed only in mind of German designers. Tests of first German heavy tanks completed by the fall of 1942 and in December 1942 the first Abteilung showed up in the front.
And re. "just" 28 round of shells of 122mm D-25 gun. I want to remind you not ot forget about HE ability of D-25 gun. JS-2, for example, was created as a heavy breakthrough tank, intended to break through the enemy's lines of defense. In other words, the main targets of this tank were infantry and artillery. History showed that the JS-2 used about 70% of its HE ammunition and only 30% of its AP ammunition.
And re. Tiger II "better reliability from the report I have already posted in this thread:
"...In the end, both captured vehicles were delivered to the NIIBT proving ground, where vehicle #102 underwent further maneuverability tests. This testing encountered severe obstacles connected with the extremely low reliability of the chassis elements, engine, and transmission. It was determined that 860 liters of fuel was sufficient for 90 km of movement over an dirt road, even though the vehicle's manual indicated that this amount of fuel should have been sufficient for 120 km. Fuel consumption per 100 km was 970 liters instead of the 700 liters according to this same (captured) manual. Average rate of movement along the highway was 25-30 km/h, 13.4-15 km/h along an dirt road. The average speed when moving over rough terrain was even worse: 6-7 km/h. The maximum speed, given as 41.5 km/h in the tank's technical documentation, was never even once achieved in the maneuverability tests..."
And some more photos for my friends.
Source:
http://www.battlefield.ru
Best Regards from Russia,