How wheeled-tracked tanks died out

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How wheeled-tracked tanks died out
Experienced wheeled-tracked tank T-29. Source: t34inform.ru


Tanks quickly acquired powerful guns and good armor, but their mobility for a long time left much to be desired. Engineers did not immediately find the best technical solutions, so different approaches developed in different countries. The French, for example, used Kegresse rubber tracks, while the Germans struggled with complex transmissions and tracks with rubber shoes on bearings.



Meanwhile, in the Soviet Union, the military became interested in wheeled-tracked tanks. Under the influence of BT tanks, the idea arose to convert other vehicles to wheeled-tracked vehicles, from a floating wedge to a medium multi-turret tank. Engineers developed designs in different weight classes, but soon the fashion for wheeled travel became a thing of the past as quickly as it arose.

In this article we will look at the idea of ​​​​a wheeled-tracked vehicle and trace how its development reached a dead end.

Walter Christie's legacy


At the beginning of the 150th century, tracked vehicles suffered from extremely low track life. For example, Renault FT tracks lasted only 200–3000 km, and this despite the fact that the tank crawled at walking speed. It is not surprising that in those years small tanks like the FIAT 1 or MS-XNUMX, which fit entirely into the back of a truck, were popular.

A caterpillar drive was needed only in difficult conditions, and on good roads it was possible to move on wheels. Naturally, the idea arose to combine wheeled and tracked travel. Engineers proposed several options with lowering wheels or tracks, but the best solution was invented by the American Walter Christie. Before getting into military technology, Christie built unique front-wheel drive race cars and raced himself. And later he decided to create the fastest tank.


Walter Christie in his front-wheel drive race car, with typical cars of that era to his right.


Demonstration of the Christie tank in America on wheels and tracks.

To achieve high speeds, it was necessary to solve three main issues:

  1. Early tracks and small-diameter road wheels had a low service life. Christie proposed a chassis with very large diameter road wheels. If necessary, the tracks were removed and the tank turned into a wheeled armored vehicle. Larger rollers have lower rolling resistance and their rubber tires last longer.

  2. Typical locked suspensions of the time were not suitable for high speeds. Christie created a custom suspension with large coil springs that provided plenty of travel and a smooth ride at high speeds. True, the coil springs themselves did not dampen longitudinal vibrations well. Later, Christie introduced shock absorbers to reduce sway.

  3. The primitive turning mechanisms of tracked vehicles did not provide adequate controllability. Christie proposed making the first pair of rollers steerable, that is, on wheels, the driver steered like a car. Before the invention of dual-flow transmissions, there were, in fact, no other alternatives.

Christie's M1931 tanks were a spectacular technology demonstrator and addressed all three issues. At the beginning of 1931, two improved M1940 chassis entered the Soviet Union and served as the basis for the BT tanks, and at the same time “infected” the Soviet military with the idea of ​​a wheeled-tracked drive.

Appetite comes with eating


Walter Christie created the fastest tanks of his time by solving basic problems. But just as important, his approach was simple and technically sound. Christie's tanks had simple onboard clutches and primitive gearboxes with moving gears. The fan was mounted on the same shaft as the clutch, so a separate drive was not required for it. Individual spring suspension cannot be called complex either.






From top to bottom: T-46, PT-1 amphibious tank and T-43-1 wedge on wheels. Source: t34inform.ru

Christie's technical solutions greatly influenced Soviet tank building and were retained even on the T-34-85. And then, in 1934, the Soviet Union was experiencing a real wheeled-tracked epidemic. To replace the T-26 with its weak chassis, the T-46 was designed with a spring suspension and two pairs of drive road wheels. Dissatisfaction with the fragile and complex chassis of the T-28 led to the creation of the wheeled-tracked three-turret tank T-29. At the same time, the PT-1 wheeled-tracked amphibious tank was designed, in which all the road wheels were driven. The T-43 floating wedge was tested, also, of course, wheeled and tracked.

In addition to creating new wheeled-tracked tanks, engineers also developed the wheeled-tracked propulsion system itself. A group led by inventor Nikolai Tsyganov created the BT-IS tank with a drive of six road wheels instead of two. Cross-country ability on wheels has increased, and the turning radius has decreased. Thanks to the synchronizer, the tank could drive steadily with one track and even retain mobility without a pair of rollers. True, the drive complicated the design and suffered from breakdowns.


BT-IS with a drive for six rollers without external armor. They tried not to touch the basic design of the tank, so the implementation was far from ideal.

The appropriate question here is: how necessary was all this activity?

Apart from the Soviet Union, no one was engaged in wheeled-tracked tanks on such a scale; the rest did without it. British cruiser tanks were initially purely tracked, and Christie himself refused to have wheels. This is because the possibility of moving on wheels, which was initially very attractive, began to bring more problems than benefits. And further story Soviet tanks show this well.

From wheels to tracks


The Christie tank chassis shipped to the Soviet Union weighed about 10 tons without the turret. Production tanks gradually became heavier and heavier. The diesel BT-7M already weighed almost 15 tons, while the dimensions of its road wheels were similar to Christie’s original design. As a result of overload, the rubber tires could collapse in just 50–100 kilometers without tracks. For comparison: on caterpillar tracks their service life was about 2 kilometers.

In July 1938, the head of ABTU Pavlov and military commissar Alliluyev reported disappointingly:

It should be noted that the extremely short service life of tires on wheels is explained by the fact that:
a) the resistance to movement increases compared to rolling wheels along the caterpillar track, which increases the temperature of the rubber;
b) dynamic effects on rubber increase due to the unevenness of the track, which also increases the temperature of the rubber;
c) the profile of the track has a greater effect on wheeled travel than on tracked ones, and leads to faster destruction of the internal tires of the wheel;
d) the cooling conditions for rubber on wheels are less favorable than on tracks - heat is transferred better through the caterpillar.
However, you need to keep in mind that even on caterpillar tracks, the tires are at their limit. It is enough to overload the second supporting wheels of the BT-8 [another designation BT-7M] with 2 kg. up to 200 kg, so that the service life of the rubber is reduced from 2 kg. up to 500.

(From the report to the People's Commissar of Defense Marshal Voroshilov).

It turns out that the BT-7M was called a wheeled-tracked tank very conditionally. Problems with wear of the rollers were also observed in the T-29 with a two-man turret, but the military wanted a heavier three-man turret.

What happens? Early tracks had a low resource, so wheel travel was required to cover a significant distance at high speed. Now everything depended on the survivability of the rubber bands, so in order to go far and quickly a caterpillar drive was required. Fortunately, new wear-resistant grades have significantly increased the service life of the tracks.

Wheel deadlock


Soviet engineers tried to adapt the wheeled-tracked propulsion system to increasingly greater loads. To do this, they had three options: make the rollers wider, increase their number, and provide a drive for all rollers except the steerable ones. The latter way does not specifically concern the survivability of rubber bands, but creating a tank weighing 20–30 tons with one pair of drive road wheels, you will agree, is a strange idea. In this form, it will have too low cross-country ability on wheels.


A-20 on wheels during joint tests with the A-32. Source: t34inform.ru

The new A-20 tank received a drive for six road wheels with wider tires. Tests showed that engineers were able to increase the resource:

Rubber on wheels at an ambient temperature of 25–30˚ at an average speed of pure movement of 40 km/h with continuous movement from 25 to 100 km worked until it was destroyed for 700 km on a crushed stone highway and 400 km on a dirt road, while A- 7 [BT-7] under the same conditions costs 50–100 km. On caterpillar tracks, the tires lasted 3 km.

(From a report on field testing of A-20 and A-32 tanks, July 18 - August 23, 1939.).

And let us repeat the question again, now rhetorically: was all this really necessary?

On tracks, the A-20 achieved average net speeds of 44,4 km/h on the highway and 31,7 km/h on the ground, and its estimated maximum speed was 75 km/h. It's a sin to complain! And the caterpillar resource was quite decent:

After 1–000 km. They rebuilt the caterpillar and replaced all the pins. Caterpillar service life on machine. "A-1" about 200 km.

(From the appendix to the report on field tests of the A-20 and A-32 tanks, July - October 1939.).

The tracks were rebuilt after 1–000 km, and rubber tires on wheels under the same conditions lasted for 1–200 km. And again, the resource is limited by rubber.

In addition, six-wheel drive complicated the design, and replacing it required removing the engine, radiators and transmission. Maintenance was also more complicated, and this is with eight rollers versus ten:

The A-20 is more difficult to maintain than the vehicle. A-32, thanks to additional lubrication points.
In mash. A-20 – 65 points.
In mash. A-32 – 21 points.

(From the appendix to the report on field tests of the A-20 and A-32 tanks, July - October 1939.).

From the point of view of repair and maintenance, the wheeled-tracked A-20 with eight road wheels is more complex than the tracked A-32 with ten rollers. It is not surprising that Soviet engineers were in no hurry to add a fifth pair of rollers on wheeled-tracked tanks.




On top is an A-20 on tracks, on the bottom is an A-32. Source: t34inform.ru

In general, the history of the A-20 perfectly shows how and why wheeled-tracked tanks reached a dead end. Christie proposed the idea of ​​a high-speed tank weighing about 10 tons with a simple design. Subsequently, the tanks became increasingly heavier, so in order to maintain wheel travel with adequate cross-country ability, the transmission had to be complicated.

Refusal of the “sharp” nose of the hull forced the rotation of the steered wheels to be limited and controllability worsened.

Finally, the rubber tires began to barely cope, so the life of the undercarriage on tracks made of stronger steel turned out to be higher than on wheels.

Thus, wheeled-tracked tanks lost their advantages, exacerbating their disadvantages.
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  1. +1
    21 December 2023 04: 10
    Yes, in fact, the failure of the summer of 41... there was no organization of armies, they were considered separate, with almost no support from motorized infantry or anti-tank artillery. the vast majority of tanks died on marches and not in battle, sometimes hundreds of kilometers away. They rushed about with one idea, then with another.... when they already had A-32s, etc.
    1. +3
      21 December 2023 04: 47
      Quote from Enceladus
      Yes, in fact, the failure of the summer of 41... there was no organization of armies, they were considered separate, with almost no support from motorized infantry or anti-tank artillery. the vast majority of tanks died on marches and not in battle, sometimes hundreds of kilometers away. They rushed about with one idea, then with another.... when they already had A-32s, etc.

      Replace the year with 39-40 and we can talk about Poland and France...
      And the throwing, of course, took up money and time, but it stopped almost on time.
  2. +10
    21 December 2023 05: 43
    Honestly. Recently, VO has been irritated by Zen- and Tik-Tok-level works.
    Reading the “arguments” in the article, I am afraid to surprise the Author that the topic of wheeled-tracked vehicles was repeatedly returned to in the USSR and the USA, both during the war years and after. Moreover, the speed or resource of the psaltery was not always put at the edge of the corner.
    For example, our ZIS-41 and fence M3. Kubinka also has two prototypes of mixed-propulsion infantry fighting vehicles.
    The bottom line is that the topic has not been covered by the Author!
    1. +14
      21 December 2023 06: 20
      Half-gears that simultaneously use wheels and tracks should not be interfered with and confused with wheeled-tracked vehicles that use both propulsion systems alternately. There were many more tank projects that had wheeled and tracked propulsion at the same time and even with the ability to change propulsion on the move. For example, the Czechoslovak KH series, the Swedish Landswerk, the latter was even in service. I can imagine how complex the mechanisms were and how reliable they were, because this was the interwar period, and the tank was not an excavator, barely crawling along the face a few meters on tracks with a chain drive. Moreover, the wheeled-tracked theme was returned to after the war.
      It is interesting that this idea still found limited application in construction equipment; there are photographs of an excavator with a wheeled-tracked drive; fortunately, hydraulics made it possible to significantly simplify this mechanism and make it more reliable.
      1. +6
        21 December 2023 08: 04
        Quote: Corvair
        The wheeled-tracked theme was also returned to after the war.
        1. +1
          21 December 2023 23: 21
          Who can tell me why the tank's road wheel (object 187) has a tread:
    2. +11
      21 December 2023 08: 43
      Honestly. Recently, VO has been irritated by Zen- and Tik-Tok-level works

      It’s hard to disagree with you on this.
      For example, our ZIS-41 and fence M3.

      These are still not wheeled-tracked vehicles, but half-tracked ones. These are different types of transmission.
      1. +11
        21 December 2023 10: 44
        I agree with you that the “intelligence” of VO has decreased significantly in recent years! But this is a “double-sided” phenomenon! The “intelligence” of VO subscribers has also become significantly lower! The “intelligent” “bison” that previously “grazed” on VO have become extinct!
        1. +13
          21 December 2023 10: 55
          The “intelligent” “bison” that previously “grazed” on VO have become extinct!

          Here it is worth deciding what is primary and what is secondary.
          “Bison” “died out” from “lack of food.” And those who tried to protest were finished off with administrative resources. What do they “graze” on? “Mitrofanovshchina,” you know, is not the best “fodder,” just like guessing whether Elizabeth I was a virgin.
          Now the “bison” have been replaced by omnivorous hamsters. Clickbait doesn’t care who clicks. And there are an order of magnitude less worries.
          1. +3
            22 December 2023 15: 19
            Oh how right you are...(((((((((((
    3. +4
      21 December 2023 14: 53
      What does half-tracked vehicles have to do with it if we are talking about wheeled-tracked tanks? Moreover, a specific type, without lowered tracks.

      The bottom line is that the topic has not been covered by the Author!

      I didn't intend to write about half-tracks.
  3. +1
    21 December 2023 06: 16
    Renault FT tracks lasted only 150–200 km, and this despite the fact that the tank crawled at walking speed. It is not surprising that in those years small tanks like the FIAT 3000 or MS-1, which fit entirely into the back of a truck, were popular.

    1. MS-1 is a modernized Soviet-made Renault.
    2. What kind of truck from the 20s of the 6th century could carry 1 tons of cargo (MS-18, while the T-5.9 weighed XNUMX tons)?
    1. +10
      21 December 2023 06: 41
      Quote: Amateur
      2. What kind of truck from the 20s of the 6th century could carry 1 tons of cargo (MS-18, while the T-5.9 weighed XNUMX tons)?

      375-pound Büssing Typ VI of the Moscow City Government on an advertisement for Rostov. 1908
      375 pounds is exactly 6 tons.
      1. -5
        21 December 2023 07: 08
        All Moscow Bussings had 30 hp engines. and could transport 5–6 tons of cargo.
        (https://gruzovikpress.ru/article/18194-istoriya-avtomobilnoy-marki-buessing-motornye-gruzovozy-i-omnibusy-byussing-ch-1/)

        30 hp for 6 tons of cargo + the car itself? Perhaps only on a horizontal, absolutely flat platform...
        1. +2
          21 December 2023 07: 15
          [quote=Amateur][quote]
          30 hp for 6 tons of cargo + the car itself? Isn’t 1908 confusing if it’s only on a horizontal, absolutely flat platform...[/quote]?
        2. +3
          21 December 2023 09: 12
          they drove normally, plus don’t forget about the heavy steam trucks
        3. +6
          21 December 2023 09: 27
          With a good reduction in the transmission it will pull, albeit slowly. And they tried to make the slopes on the first highways as small as possible, so that the trucks of that time, albeit slowly, would roll uphill.
    2. +8
      21 December 2023 08: 54
      What kind of truck from the 20s of the 6th century could carry XNUMX tons of cargo?

      For example, the Renault FU transporter, manufactured in 1917, specially designed for transporting tanks.
    3. +5
      21 December 2023 14: 57
      1. MS-1 is a modernized Soviet-made Renault.

      This is a completely new tank, with a single block of engine and transmission mounted transversely. Don't confuse it with Renault-Russian. You've already been answered for the trucks.
  4. +4
    21 December 2023 06: 22
    Christie proposed the idea of ​​a high-speed tank weighing about 10 tons with a simple design.

    In the modern world, the equivalent is various MRAPs that have a high mileage on the roads. Perhaps, if you do them with a mixed stroke, then the rubber must be forcibly cooled.
    1. 0
      22 December 2023 14: 25
      Not the same at all. Christie made tanks. And without a tower. And not armored trucks
  5. -4
    21 December 2023 06: 40
    Wheeled-tracked tanks lost their advantages, exacerbating their disadvantages.
    Everything has its time. When they planned to fight on enemy territory and quickly advance along European roads, the idea of ​​a wheeled-tracked tank was in demand. But when using such a scheme, “suddenly” (?) we encountered a number of practical problems that should have arisen during the design. And gradually this scheme came to naught.
    1. +6
      21 December 2023 10: 57
      Quote: rotmistr60
      Everything has its time. When they planned to fight on enemy territory and quickly advance along European roads, the idea of ​​a wheeled-tracked tank was in demand.

      The problem is that wheel travel on paved roads is of little use due to the too rapid destruction of tires.
      BTs on wheels felt best somewhere in Mongolia.
      1. +2
        22 December 2023 14: 29
        Quote: Alexey RA

        The problem is that wheel travel on paved roads is of little use due to the too rapid destruction of tires.

        ... And on soft-surface roads it has a physical weight limit of approximately 20 tons. If the tank exceeds 20 tons, the wheels tear off the top layer of soil.
    2. +5
      21 December 2023 11: 35
      Quote: rotmistr60
      planned to fight on enemy territory and quickly advance along European roads

      Did anyone actually plan to “advance quickly along European roads”? Does this idea come from Rezun and his famous “highway tanks”?
      1. +1
        21 December 2023 11: 39
        Does this idea come from Rezun?
        No. In the Soviet military doctrine of the 30s it was written that the Red Army, having repelled the attack of the enemy (aggressor), would inflict a crushing defeat on him and, having driven him back, would conduct military operations on his territory.
        1. +4
          21 December 2023 11: 44
          Quote: rotmistr60
          In the Soviet military doctrine of the 30s it was written

          This is not the same thing.
        2. +6
          21 December 2023 17: 10
          Quote: rotmistr60
          In the Soviet military doctrine of the 30s it was written that the Red Army, having repelled the attack of the enemy (aggressor), would inflict a crushing defeat on him and, having driven him back, would conduct military operations on his territory.

          Yeah... at the same time, the country was preparing throughout the 30s to wage a war of attrition, constantly increasing the size of the areas evacuated at the beginning of the war. smile
          It should be noted that the propaganda speeches of political and military leaders contained somewhat different tasks than the military plans developed under their leadership. So, in 1936, K. Ye. Voroshilov proclaimed the slogan that the Red Army would wage war "with little blood and on foreign territory." But this statement did not prevent the approval of the next year’s plan of evacuation from areas that may be occupied by the enemy, and the next norms of losses for the year of the war, which had very little in common with the mentioned slogan. Therefore, when analyzing preparations for war, it is very important to separate political propaganda from the real direction of military planning.
          © Melia A.A. Mobilization training of the national economy of the USSR.
          ...the active, offensive nature of the operational-tactical doctrine of the Red Army does not at all exclude the possibility and expediency of both defense and even temporary retreat - in cases where the latter is necessary and appropriate. We must take into account the specific situation, and when necessary, be able to retreat, and when to advance. Lenin repeatedly pointed out that even our party experienced temporary defeats and was forced to retreat and, while retreating, to maneuver. “You cannot win,” said Lenin, “without learning the correct attack and the correct retreat” (Lenin, volume XXV, p. 177).
          Forgetting this rule leads to neglect of the laws of the offensive, which can be successful only when “... when people do not limit themselves to indiscriminate advance forward, but at the same time try to consolidate captured positions, regroup their forces in accordance with the changed situation, tighten up their rear, bring in reserves "(Stalin. Questions of Leninism. 10th edition, p. 336). Only this helps to avoid surprises and individual breakthroughs “... from which no offensive is guaranteed” (Stalin, ibid.).
          These laws of strategy and tactics are actually neglected. Organized withdrawal, organized retreat in certain areas began to be considered a disgrace. The infantry combat manual directly directs commanders towards meaningless sacrifices, indicating that “no losses can force a company to stop performing a combat mission, even if only a few people remain in it” (BUP-40, part II, p. 7).
          Obviously, the the theory of an indiscriminate offensive must be decisively and quickly put an end to, because it leads to arrogance, mischief and one-sidedness in army preparation.

          © Speech by L. 3. Mehlis at a meeting on ideological work in the army and navy on May 13, 1940
      2. PPD
        0
        21 December 2023 23: 20
        In this case, Rezun will only reprint other people’s articles.
        And it’s wrong.
        How is it, as the veterans said...
        Yeah, the veterans told him...
        There was an article in the newspaper, and in more than one newspaper, where all this was stated - about highways.
        It's a small newspaper, what's from veterans and what's from the wild fantasies of correspondents is a mystery.
        But it was stated on paper.
        In principle - why not?
        You never know what ideas arose from the beginning.
        Practice has made adjustments.
  6. +7
    21 December 2023 07: 25
    Why be surprised, tanks were at the beginning of their development, they tried different directions, and that’s how evolution goes! In the famous game, by the way, you can ride all these tanks, it’s very interesting :))
  7. +6
    21 December 2023 10: 05
    The author decided to talk about “Christie’s legacy,” but, unfortunately, “he didn’t learn his lesson well,” so the story turned out to be very mediocre. In addition, the author “started” for some reason in 1931, while Christie began creating wheeled-tracked tanks in 1918 and by 1921 produced, as the article says, a “technology demonstrator” - the M1921 wheeled-tracked tank (first photo ).
    Early in 1931, two improved M1940 chassis

    Such chassis did not exist in nature. The USSR bought the M1931. M1940 is the unofficial name of the M1928, which Christie used for advertising purposes, declaring that his design was 12 years ahead of its time.
    In addition to the USSR, in the thirties the Poles worked hard on a wheeled-tracked tank with a Christie transmission. They were unable to buy the tank, but from Christie they received several sketches of its improved suspension with horizontal movement, which made it possible to significantly increase the suspension travel.
    In total, the Poles spent seven years and after testing the 1939TR tank in 10 (second photo) they came to the conclusion that the wheeled-tracked propulsion system was simply excess weight and a complication of the design.
    1. 0
      21 December 2023 15: 04
      In addition, the author “started” for some reason in 1931, while Christie began creating wheeled-tracked tanks in 1918

      I'm aware of Christie's early work, but this is an article about how and why Soviet wheeled-tracked tanks ended, not about how American ones began. A brief description of Christie's ideas at the beginning is necessary in order to compare them with the resulting result of evolution.

      Such chassis did not exist in nature. The USSR bought the M1931.

      Pasholok wrote about the M1940 more than once, I repeated it without hesitation. Let me clarify this point.
      1. +2
        21 December 2023 15: 15
        the result of evolution.

        What was evolution expressed in? What fundamental changes did the USSR make to the suspension design so that we could talk about evolution?
        1. -2
          21 December 2023 15: 36
          Why the suspension design? We are talking about the tank chassis as a whole. The evolution is as follows: the front part of the body has been widened, limiting the angle of rotation of the front rollers; added a drive for several pairs of rollers; provided a synchronizer for movement on one track; Wheels with camber were installed. With the exception of the last one, everything else is mentioned in the article.

          Compare this with Christie's own approach, which added shock absorbers to dampen vibrations, set the suspension springs at a higher angle and abandoned the wheel travel.
          1. +3
            21 December 2023 18: 58
            The evolution is as follows: the front part of the body has been widened, limiting the angle of rotation of the front rollers; added a drive for several pairs of rollers; provided a synchronizer for movement on one track; Wheels with camber were installed.

            None of these “evolutionary changes” were used on production tanks.
            Compare this with Christie's own approach, which added shock absorbers to dampen vibrations, set the suspension springs at a higher angle and abandoned the wheel travel.

            The USSR eventually followed this path - they abandoned the wheel drive and installed springs at an angle. The result was the T-34.
            But why in the USSR they tried to produce a wheeled-tracked tank when everyone had already abandoned it, even the Poles, due to its futility, you never answered.
            1. 0
              22 December 2023 05: 03
              None of these “evolutionary changes” were used on production tanks.

              So what? Examples from the article show what difficulties engineers faced and why the development of wheeled-tracked tanks led to unsuccessful compromises. It doesn’t matter on which machines this was achieved, serial or experimental, the laws of physics are the same for everyone.

              But why in the USSR they tried to produce a wheeled-tracked tank when everyone had already abandoned it, even the Poles, due to its futility, you never answered.

              You are asking the question incorrectly. There was no single wheeled-tracked tank; we are talking about different developments with different fates, and each of them needs to be written separately. The T-46, for example, turned out to be unreasonably complex; the very idea of ​​​​crossing Christie with the T-26 layout was unsuccessful. Christie had both the gearbox and the drive of the drive rollers at the rear. On the T-46, the gearbox was placed in the center under the turret and the shafts were pulled from it forward and backward, because on a wheeled vehicle the drive wheels were at the rear, and on a tracked vehicle the sprockets were in front. The T-29 has its own sad history, and so on.

              But they have common points, this is the complication of the design and the struggle for the survivability of the rubber. This is described in the article using the A-20 as an example.
              1. +1
                22 December 2023 10: 21
                Quote from: geraet4501
                The T-29 has its own sad history, and so on.

                The saddest thing in the history of the T-29 is its price. However, nothing surprising - this is LKZ. wink
                And so... everything is standard for wheeled-tracked tanks. The T-29 was simply too late to be born - when the decision was made on it, the T-28 had already gotten rid of most childhood illnesses and was no longer inferior to its wheeled “replacer” in terms of track life and speed.
                1. 0
                  22 December 2023 10: 43
                  The T-28 had already gotten rid of most childhood diseases and was no longer inferior to its wheeled “changer” in terms of track life and speed.

                  You are mistaken in associating the transition to a wheel-tracked system only with the service life of the tracks. The T-28 had a too weak and fragile suspension, which provided excellent smoothness and very uniform load transfer to the tracks, but was not at all suitable for high-speed vehicles. The T-29 had a simpler suspension that was suitable for high speeds.

                  Pasholok, in an article about the T-29, provided the following data:
                  “The car turned out to be much faster than the serial T-28, and its chassis was more reliable. For comparison, trouble-free driving of the T-29 off-road was possible at a speed of 20-25 km/h, while the car overcame bumps up to 0,5- 0,6 meters. On the T-28, the destruction of the chassis began when driving off-road at a speed of 15-18 km/h, while the height of vertical obstacles to be overcome was only 0,2-0,3 meters."

                  At the beginning of the article, I specifically gave a whole list of problems that Christie solved on his tanks, and it’s not just the issue of track life. And I also mentioned the fragility of the T-28 chassis.
            2. -2
              22 December 2023 14: 52
              Quote: Dekabrist
              But why in the USSR they tried to produce a wheeled-tracked tank when everyone had already abandoned it, even the Poles, due to its futility, you never answered.

              Firstly, they did not try, but produced.
              Secondly, no one refused the “already”, because no one tried. Christie failed to interest the US military not because of the suspension, but because of the eccentric overall design of the tanks. But there was a problem of increasing the speed of tanks and they tried to solve it.
              Thirdly, the answer to your question, in my opinion, is simple: because the existing tanks were not satisfactory in terms of speed characteristics.
              1. +4
                22 December 2023 15: 00
                Secondly, no one refused the “already”, because no one tried.

                The story there is actually more complex and interesting than it is presented. In the 30s, Christie abandoned wheels and showed purely tracked models. The British immediately made their cruising tanks purely tracked. But looking at this, the French concocted the AMX 1940 project in 40 under the obvious influence of Christie. Pasholok described this tank as purely tracked, but this is not so. The drawing shows gearboxes for the last two pairs of rollers for wheel travel, and the driver had a steering wheel. That is, AMX seriously proposed a wheeled-tracked tank with a specific power of 10 hp/t, 60 mm armor and a two-stroke diesel engine.

                but because of the eccentric overall design of the tanks.

                I don't quite agree. The M1931 was quite good in overall design, compare with the lightweight T1 of the time, where the driver hugs the engine with his legs and the commander sits on the gearbox. The problem is that Christie stubbornly refused to listen to what exactly the military needed, and used good chassis for strange purposes.
              2. +2
                22 December 2023 15: 18
                no one tried it.

                Exactly. What about the British A13E2?
                1. +3
                  22 December 2023 17: 16
                  Christie sold the British an old car, essentially a prototype of the tanks that went to the USSR and gave birth to the BT-2. But what is characteristic is that the British, having redesigned the design, immediately abandoned the wheel drive. And Christie, having received the money, built the M1937, also without wheels.
        2. -2
          22 December 2023 14: 43
          First of all, BT tanks showed that a tank with decent armament and armor can be fast. For example, the BT-7A with a 76-mm cannon reached a speed of 70+ km/h. Comparable in armor to the 45-mm T-26 cannon - 30 km/h. Therefore, when the T-34 was designed, it was immediately given high speed parameters of more than 50 km/h (highway speed). And given that the T-34 already had shell-proof armor, this made tank formations a different kind of tool than in the case of cruising and infantry tanks of the 30s.
          1. +1
            22 December 2023 15: 11
            First of all, BT tanks showed that a tank with decent armament and armor can be fast.

            Christie proved with his T3E2 and the British with their Cruiser Tank Mk IV that a tank with decent armament and bulletproof armor can be fast. BT tanks did not contribute anything revolutionary.
            But the question was not about “what was shown,” but about what fundamental changes, compared to Christie’s design, were made in the USSR. It turns out - none.
            1. -2
              22 December 2023 17: 18
              But the question was not about “what was shown,” but about what fundamental changes, compared to Christie’s design, were made in the USSR. It turns out - none.

              You are playing with words. On serial BTs they did not. On other tanks, a small but important list is being collected. Why they didn’t go into the series is another question, and some reasons have nothing to do with Christie’s ideas at all.
            2. -2
              22 December 2023 19: 54
              Quote: Dekabrist
              Christie proved that a tank with decent armament and bulletproof armor can be fast with his T3E2

              This is the one that was released in as many as three pieces? And I didn’t go further than the training ground. Dashingly proved what to say :)
              This is not proof - it is failure.
              The British T3E2 in 1938 just STARTED designing. By this time, the USSR already had more than 3000 BT-2, BT-5 and BT-7 in its army.
              Here, objectively speaking, the British rather followed the USSR.

              Have you seen what kind of tanks Christie actually designed? There in the picture is the 1928 model, which is actually a clear example of the “Christie tank”.
              Moreover, I note that in 1930, when the “Christie tanks” arrived in the USSR, they did not have any turrets. There wasn't at all. Christie installed the turret on his chassis only in 1931, although, as evil tongues claim, he received an order for 7 vehicles from the US Department of Defense precisely under the influence of a contract with the USSR.
              So the first fundamental change was that a gun turret was installed on the Christie chassis in the USSR. And almost AT THE SAME TIME in the USA, Christie himself receives an order from the Ministry of Defense for the M1931, which was actually the M1928, but with a turret, and in the USSR they are launching the BT-2 into production. And the first tanks more or less similar to the Soviet BT-2 went to a training ground in the USA in 1932. This year, 396 BT-2s were already produced in the USSR
              First, you need to restore the chronology of events correctly.
              1. +2
                22 December 2023 21: 15
                You have an argument like Anselm of Canterbury, when a fact is considered proven by the very fact of its existence. All the best.
                1. -1
                  25 December 2023 01: 37
                  Chronology, my friend, it’s like a concrete wall. You could even kill yourself about it, but it’s like that...
              2. +1
                23 December 2023 05: 32
                Here, objectively speaking, the British rather followed the USSR.

                This is true. The British saw the maneuvers of Soviet tanks and were impressed by the BT. Here the Soviet example is obvious.

                Have you seen what kind of tanks Christie actually designed? There in the picture is the 1928 model, which is actually a clear example of the “Christie tank”.
                Moreover, I note that in 1930, when the “Christie tanks” arrived in the USSR, they did not have any turrets.

                But I don’t agree here. Yes, the M1928 did not have a turret. But then Christie sold the American military the M1931 with turrets. And the Soviet Union received a chassis for the turret. Yes, there was no tower there, but there was a shoulder strap for it, it is visible in the photographs. And there is a drawing of the Christie tank with a turret, the same one that Soviet specialists saw.
                1. 0
                  25 December 2023 02: 49
                  Let's try to restore the chronology...
                  On August 22, 1929, the US Cavalry “purchases” the M-1928 as is, without a turret. BUT the "infantry" demands changes.
                  In January 1930, Christie submitted the updated vehicle with a turret for new tests.
                  On December 24, 1930, two “tractors” were sent to the USSR, without towers.
                  On March 14, 1931, the tank was already rolled out in Kubinka and shown to representatives of the Red Army command.
                  Yes, it turns out that you are right, Christy installed the turret on the chassis before ours.

                  As I understand it, Christie had no towers at all; because of this, he incurred penalties under the agreement with the USSR. And whether there was a shoulder strap in the buildings or just an opening left - I don’t know. Tests of the “Original 1” and “Original 2” samples of 1931 revealed a number of shortcomings and shortcomings. This led to the conclusion that it was impossible to directly copy samples at a serial enterprise. And a special one was created. Toskin Design Bureau and it, as they write, “began refining the samples.” I searched at the time, but did not find a list of what exactly was modified, and judging by the available photos of the BT-2 and the M1931 itself with a turret, the turrets there are completely different and the location of the weapons does not match. But whether in the USSR the tower was made to fit the existing shoulder strap or the shoulder strap was designed along with the tower - I don’t know.

                  Well, Christy didn’t like tanks with turrets :)
  8. +7
    21 December 2023 11: 11
    And the caterpillar resource was quite decent:
    After 1–000 km. They rebuilt the caterpillar and replaced all the pins. Caterpillar service life on machine. "A-1" about 200 km.

    It should be noted that this is the track resource of an experienced tank.
    The difference between the experimental and production vehicle is clearly visible in the example of the A-34 / T-34.
    16/XI this year At the direction of the NKSM and the GABTU of the Red Army, at plant No. 183, sea trials of 3 A-34 vehicles were carried out for 3000 kilometers.
    During the run, significant design flaws were identified in the tested vehicles, which caused the tanks to fail.
    (...)
    Cast tracks of caterpillars quickly failed, broke off. During the run, 3 sets of tracks were replaced.
    It should be noted that on the tanks tested by the state commission, the tracks were made up of stamped tracks that could withstand 3000 kilometers, however, after the launch into series, on the initiative of plant No. 183 and with the consent of the NKSM and the GABTU of the Red Army, the stamped tracks were replaced by cast ones, which did not pass the warranty mileage tests .
    Rubber on all wheels collapsed and broke off. For the tanks tested by the State Commission, the Yaroslavl Rubber-Asbestos Plant has manufactured high-quality heavy-duty tires that can withstand 6000 kilometers of run, and for mass production, heavy-duty tires are manufactured that can withstand only 2000 kilometers.
    © Deputy People's Commissar of Internal Affairs of the Ukrainian SSR, State Security Major Tkachenko. REPORT. On the state of production of A-34 tanks at plant No. 183 in the city. Kharkov.

    In the GABTU mileage report, the picture of the tracks appears in an even more unsightly form:
    2. Breakdowns and malfunctions:
    a) The tank tracks are completely unusable due to cracks in the tracks and stretching. The cotter pins that hold the fingers in the track eyes are cut off after 100 - 150 km. - on all machines.

    3. Condition of the tanks after the march.
    All tanks require immediate replacement of tracks - further movement without this is impossible.
    © Results of the run of T-34 tanks along the Kharkov-Kubinka route. (5-day march - 4 walking days, 1 day - technical inspection). November 1940
    4. Chassis.
    The caterpillar belt can withstand an average mileage of 500 km. Reason: incorrectly chosen geometric shape of the tracks and insufficient mechanical strength.
    Rubber support wheel tires from N.K. are destroyed after 1,5 - 2 hours of continuous movement on the highway at a speed of 30-35 km/h. Reason: high specific pressure on the support wheels. Tensioning a track with a sloth using a worm tensioning device is inconvenient, difficult and time-consuming (1,5 - 2 hours).
    © Results of the run of T-34 tanks along the route Kharkov-Kubinka-Smolensk-Orsha-Mogilev-Gomel-Kyiv-Poltava-Kharkov. December 1940
    1. -1
      21 December 2023 15: 05
      Well, you yourself cited the test results of a specific unsuccessful design of a cast track. It does not put an end to the caterpillar track at all. And it cannot be said that serial designs were the same all the time.
  9. +2
    21 December 2023 11: 50
    The author certainly tried. But there is nothing new in the article. All the fuss was due to the low resource of the caterpillar. As soon as they more or less mastered the technology with tracks, they abandoned wheel travel. As for the wheeled-tracked infantry fighting vehicle developed by MSTU, it showed itself well in tests, of course it’s difficult. And for hard soils it’s a very good idea.
    https://drawingstanks.blogspot.com/2014/06/20-20.html
    1. -1
      22 December 2023 04: 53
      But there is nothing new in the article.

      Rather, the point is that you couldn’t see anything new in it.

      All the boron cheese was due to the low caterpillar resource

      I have cited three main points that Christie decided; this is not only a question of the survivability of the caterpillars. And subsequently, it was Christie’s complex of decisions that influenced Soviet tanks, and not the wheeled-tracked drive itself separately. For example, the T-26 had a weak chassis with leaf springs. Such springs dampen rocking well, but at the cost of friction in the metal, hence the requirements for its quality. On early T-26s, the springs wore out very quickly, but here is an alternative in the form of a BT tank with a spring suspension, where there is simply no such problem.

      As for the wheeled-tracked infantry fighting vehicle developed by MSTU, it showed itself well in tests

      At least one commentator remembered that it weighed 13 tons. And here we are talking about tanks weighing 18-25 tons and above. In addition, that BMP on wheels carried the dead weight of the tracked chassis, and for Christie all the rollers always worked.
  10. +1
    21 December 2023 15: 44
    This looks like graphomania, the German-philic author retells what has been known for a long time from the works of other authors
    At the same time, he makes ambiguous conclusions, to put it mildly, adapting them to his point of view of the inferiority of wheeled-tracked tanks
    Let's turn to the T-34 Inform website
    II. Comparative assessment of A-20 and A-32.
    The wheeled-tracked tank A-20 has the following advantages compared to the tracked A-32:
    1. It has 80 shells and 17 machine-gun discs in its combat kit, more than the A-32.
    2. It has the ability to move on one track on dry dirt roads, terrain and overcome obstacles.
    3. After 1 - 2 wheels on one side are disabled, it can move on highways and hard ground.
    4. In emergency condition and with a damaged propulsion unit, it can be towed on wheels.
    5. Can travel on wheels on the highway at any time of the year and on dry dirt roads in a column.
    6. The A-20 tank is 1 ton lighter than the A-32.
    Along with these advantages, it has the following disadvantages compared to the A-32:
    1. Armed with a less powerful gun.
    2. Side armor 5 mm. thinner.
    3. The engine is more loaded, because has 2 fewer supporting wheels (more specific pressure).
    In tanks, with the exception of final drives and wheels, everything is the same and interchangeable. The A-20, as a wheeled-tracked tank, has more advantages in comparison with the presented A-32 model.

    It turns out, according to the commission’s conclusions, the A-20 has more advantages than the A-32, wow, but there is not a word about the disadvantages about the wear of rubber bands when driving on wheels, the necessary “consumables” so to speak, while the resource is significantly longer than that of the same BT-7, it turns out that the testers and the Red Army were more than happy with everything.
    It must be taken into account that the rubber tires of the road wheels have worked in the most extreme operating conditions, with continuous movement from 20km to 100km.
    The funny thing is that the steered wheels on the A-20 lasted 4200 km, that is, without transmitting torque to the roller, the rubber tire “lives” much longer.
    It should be taken into account that the limiting indicator is the temperature of the water (no antifreeze in summer) and oil, and not the temperature of the rubber tires of the road wheels.
    “On highways and dirt roads, it was not possible to determine the duration of movement at minimum stable speeds until the water and oil temperature rises to 100 °C. Average temperatures did not rise above 86 °C. Therefore, in 3rd and 4th gear at 500 - 600 rpm. at a speed of 10 – 18 km/h, the tank can move along dirt roads and highways for a long time.”

    What can we say as a result, wheeled-tracked tanks had the right to life, especially if you look at such capabilities
    “The fuel range varies depending on road conditions:
    BT-7 on tracks from 300 km. up to 350 km.
    BT-7 on wheels – from 480 km. up to 510 km.
    BT-7M on tracks 520 – 630 km.
    BT-7M on wheels 1070 – 1250 km.
    A-20 on tracks 350 - 400 km.
    A-20 on wheels 900 – 1000 km.
    A-32 on tracks 300 - 440 km.

    Yes, if the A-20 had been in service with the Red Army in the border districts of the summer of 1941, they would have been traveling for a long time on their supply of fuel, so it is not surprising that the tests of the A-20 dragged on until 1940, or 1941, " machine" turned out to be interesting.
    Why did they abandon wheeled-tracked tanks? Because the Red Army needed medium and light tanks with shell-proof armor from 37mm caliber, and the weight of such armor protection “cannot be lifted” on wheels.
    Wheeled-tracked tanks like the A-20 could have been an excellent replacement for various armored vehicles like the BA-10, or Sd.Kfz.234/2 Puma, but it didn’t work out.
    1. -2
      21 December 2023 16: 20
      It turns out, according to the commission’s findings, the A-20 has more advantages than the A-32, wow

      It's stupid to judge a tank by the number of items on the list. The 45-mm cannon was useless against the frontal armor of German tanks of 50-60 mm; this point alone seriously weakens the A-20.

      The funny thing is that the steered wheels on the A-20 lasted 4200 km, that is, without transmitting torque to the roller, the rubber tire “lives” much longer.

      For A-20, the load on the steering wheels is around 1600 kg, and for others it is 2500-2600 kg. The center of gravity is simply shifted and the load is distributed unevenly.

      What can we say as a result, wheeled-tracked tanks had the right to life, especially if you look at such capabilities

      What are the possibilities? They're just numbers on paper. To drive a BT-7M that far without tracks, you will have to follow it in a truck with spare rollers. This is not to mention the oil supply, replacement of pins, and tightening of bolts.

      Wheeled-tracked tanks like the A-20 could be an excellent replacement for various armored vehicles

      For the price of a medium tank, yeah.

      Why did they abandon wheeled-tracked tanks? Because the Red Army needed medium and light tanks with shell-proof armor from 37mm caliber, and the weight of such armor protection “cannot be lifted” on wheels.

      It was possible to lift it; the T-29 weighed more than the A-20. But on the A-20 it would be necessary to add a fifth pair of rollers and pull the drive to them with all that it entails.
      1. -1
        21 December 2023 20: 28
        Moreover, here is the number of items on the list; the commission members emphasized the advantages that they considered absolutely important for operation in the Red Army. And the wear of the rubber tires of the road wheels was not considered a disadvantage.
        A 45mm gun for a light tank in the Red Army was considered sufficient until the middle of the war. Nazi tanks with 50-60mm frontal armor in 1938, where???
        If you feel the need, you can put a 20mm cannon in the A-76 turret, like on the A-32, this is not the 3rd “groove”.

        I forgot about the load on the steered wheels.
        The center of gravity of the tank is where it should be for a given tank design.
        The same steered wheels can be “loaded” with additional armor or weapons.
        But the very fact is that with a load on the support roller of 1600 kg, the rubber band “lives” 4200 km, therefore, you can scale various indicators, such as the width and diameter of the support roller, the weight of the tank, the distribution of the load on the rollers, the composition of the rubber, in order to obtain acceptable survivability.

        These are just numbers on paper, these are tests in which samples of armored vehicles were “raped” in real time, on various road and other surfaces.
        Well, if you can drive a BT-7M in a day without stopping for 50-100 km to no one knows where and no one knows why, well then you will change the road wheels, and if you move normally, up to 25 km, and then stop for 20-30 minutes, like for a tank , and for the crew, then everything will be fine.

        The A-20 is not a medium tank and I very much doubt that the Sd.Kfz.234/2 Puma, which is about 5 tons lighter, costs significantly less, only because it is an armored car with its 8x8.
        And so we take any armored car and “screw” a wheeled-tracked propulsion device to it.
        You can also install pneumatic tires, Lorraine 40t will help.
        And then Kniepkamp with his staggered suspension, needle bearings and rubber boots can be safely sent to the forest, the wheeled-tracked tractor will make his half-track “crafts” like a bull does a sheep.

        Why make 3-4 driving pairs of road wheels, if you can limit yourself to even two, this is not an armored car, in which all-wheel drive is very, very desirable.
        Nowadays, there are truck tractors that pull semi-trailers weighing 20 tons.
        But what am I talking about, in the 30-40s there already existed truck tractors that hauled tanks from light to heavy on special semi-trailers and without any drive on them.
        1. -1
          22 December 2023 04: 40
          A 45mm gun for a light tank in the Red Army was considered sufficient until the middle of the war.

          It was not considered, and the T-70 was not produced because of a good life, in which something more could not be installed.

          Nazi tanks with 50-60mm frontal armor in 1938, where???

          In 1938, the A-20 looked adequate, but you yourself mentioned 1940-41. And this was the desire of the Soviet military to strengthen the armor, and later tests by shelling of the StuG III, where the 45-mm cannon did not hit its forehead at point-blank range.

          The center of gravity of the tank is where it should be for a given tank design.

          It’s amazing.

          therefore, it is possible to scale various indicators, such as the width and diameter of the road wheel, the weight of the tank, load distribution across the rollers, and rubber composition, in order to obtain acceptable survivability.

          What are you going to scale? The A-20 already has very wide bandages, you can’t gain much there. The diameter of the road wheels is limited by the fenders and the suspension travel. The load distribution is poor, because four pairs for a tank weighing almost 20 tons is in any case small. Adjusting the entire tank as a whole for the sake of one single detail - the survivability of the rubber - is complete nonsense. This design is tailored to the concept that provides the required characteristics, and not vice versa.

          What are just numbers on paper, these are tests

          Show tests where BT-7Ms travel on wheels at one gas station without repair for a thousand kilometers.

          The A-20 is not a medium tank and I very much doubt that the Sd.Kfz.234/2 Puma, which is about 5 tons lighter, costs significantly less

          The 18-ton A-20 almost reached the level of French medium tanks and was close to the German “threes” and “fours”, which we like to call medium.

          The eight-wheeled Sd.Kfz.231 weighed 8,5 tons, the Sd.Kfz.232 - 9 tons, half the weight of the A-20. The Sd.Kfz.234 in its heaviest version was 6 tons lighter than the A-20. And these were 8x8 versus 6x8 vehicles.

          Why make 3-4 driving pairs of road wheels if you can limit yourself to even two?

          Because a tank on wheels is not an asphalt vehicle. Without adequate cross-country ability, all these delights with synchronizers and the ability to continue moving on one track do not make much sense.

          Nowadays, there are truck tractors that pull semi-trailers weighing 20 tons.

          Yeah, on asphalt. Look at the photo in what conditions the A-20 on wheels was tested and think about what will happen to these tractors.
          1. -1
            22 December 2023 12: 32
            It was not because of a good life that they produced the T-60 and T-70, since they could not establish production of the T-50, which was armed with a 45mm cannon, American and British light tanks with 37-40mm cannons fought and nothing, these were the requirements for light tanks. What is much more interesting is that in the USSR they immediately installed a 76mm universal cannon on a medium tank, and the 4th “groove” until the 42nd existed with a 75mm “cigarette butt”, which seems to hint that everything was not easy with the “witness” in the Third Reich.

            Put a 20mm cannon on the A-76, like on the A-32, what’s the problem, it’s not the 3rd “groove”.

            The A-20 has a much higher service life of rubber tires than the BT-7, and since the BT series tanks were actively used throughout the 30s and early 40s, for some reason they noticed breaking gearboxes on BT series tanks, and with road wheels suddenly no apocalypse happened. This probably means that the people of that time knew how to operate it, but you cannot be trusted with a tank; it will break down the next day.

            I don’t know where to listen, but I clearly and clearly wrote, even highlighted, that according to the test results, accelerated wear of rubber tires occurs with CONTINUOUS movement FROM 25 km TO 100 km.

            The A-20 is a replacement for the BT series tanks, with improved armor and the same 45mm cannon, and is clearly not a competitor to the A-32 for the title of medium tank. In the future, most likely, it would have been converted to use the V-4 engine, making it more compact and lighter.
            On one A-20, that the world has come together like a wedge, there are no other armored vehicles?
            I told you, we’ll take an armored car, even an Sd.Kfz. 231 and instead of 8x8 we make a wheeled-tracked propulsion system, that’s all.
            You can take for example the Mk.VII “Tetrarch” tank, chassis of 8 road wheels, weight 7,62 tons.
            It is even lighter than the Christie tank, we are converting it into a wheeled and tracked propulsion unit.

            I very, very, very strongly doubt that in the 30s there was more asphalt pavement in the USSR than there is now. As we know, the whole idea with the BT series tanks was due to the low service life of the tracks, that is, we must assume that the tanks mostly moved on wheels. Starting from 11th. tank BT-2 and up to 14t. tank BT-7, the tanks had ONE LEADING PAIR of road wheels, with the help of which they “wheeled” across all the expanses of our vast homeland.
            Again the same situation, in the USSR tanks “drive”, but you should not, there are assumptions, consider that you are completely incompetent in this matter.

            Well, re-read the conditions under which they were tested
            After returning to the factory, the results of the run were summed up: during the day the A-20 tank on wheels covered exactly 300 km, of which 188 km were on a crushed stone-asphalt highway, 81 km on dirt roads, 26 km on a cobblestone highway and 5 km on on sand and sandy roads. The net movement time was 7 hours 18 minutes, the time for troubleshooting was 57 minutes, the time for rest, eating and other operational stops was 43 minutes, the average speed of net movement was 41,2 km/h, the average technical speed was 36,3 km/h, average operational speed – 33,4 km/h.
            1. 0
              22 December 2023 13: 48
              were unable to establish production of the T-50, which was armed with a 45mm cannon

              Back then they didn’t know how quickly these weapons would become obsolete, and it was impossible to strengthen them within the framework of a three-man turret.

              American and British light tanks with 37-40mm guns fought and nothing happened, these were the requirements for light tanks

              Stuarts were much lighter and cheaper than Shermans, so they were suitable for the role of budget mass vehicles. And the 37-mm American gun was better than the forty-five. And you are seriously suggesting the A-20 for the role of a light tank a la T-50, despite the fact that in terms of chassis design it is at the level of the T-34. It's like Stuart cutting off the armor from a Sherman.

              Put a 20mm cannon on the A-76, like on the A-32, what’s the problem, it’s not the 3rd “groove”.

              Why is it needed if there is a normal medium tank with a 76 mm cannon on a similar chassis?

              This probably means that the people of that time knew how to operate

              We open Zheltov and Pavlov and read about the wonders of exploitation:

              “The only defect of all BT series machines, which could not be eliminated over all the years of their production, was the short service life of the rubber tires of the road wheels, but this was a purely technological defect. The Yaroslavl Rubber Products Plant could not provide the necessary rubber service life due to its "double" use with a given wheeled-tracked propulsion system of the vehicle. Therefore, with a further increase in the weight of the vehicle during mass production, and subsequently when installing a diesel engine, it was recommended to operate BT-7 tanks in the army only on a tracked propulsion system."
              http://militera.lib.ru/tw/pavlov_zheltov_pavlov/12.html

              Accelerated wear of rubber bands occurs during CONTINUOUS movement from 25 km to 100 km.

              Once again, tracked rollers will ALWAYS last longer than wheeled ones. And if on tracks the running life is longer and the speed is high enough, then there is NO point in using wheels. Therefore, instead of the A-20, a purely tracked tank went into production.

              In the future, most likely, it would have been converted to use the V-4 engine, making it more compact and lighter.

              I spread my hands. And how do you imagine this?

              we make a wheeled-tracked propulsion system, that’s all.

              we are converting it into a wheeled-tracked propulsion unit.

              And why, having the example of BT before our eyes, was not remade? Are there fools all around whom you haven’t had time to open your eyes?

              that is, we must assume that the tanks mostly moved on wheels

              We must rely not on fantasies, but on sources. Where can I see this?
              1. -1
                22 December 2023 16: 50
                Why will the 45mm gun become obsolete? The T-50 is a development of the infantry support tank, with which it moves in the second echelon, and in the first echelon the T-34 and KV are supposed to “thin out” the enemy’s defenses. The missions for the T-60, T-70, T-80, SU-76, Mk.III “Valentine” and Mk.II “Matilda II” were virtually unchanged during the war years.

                The A-20 is not a replacement for the T-50, it is a replacement for BT tanks, that is, long-range tanks, that is, T-34 and KV tanks break through enemy defenses and then BT or A-20 are introduced into the breakthrough to develop success, since from A- 20 refused, and the T-34 took over its functions.

                The A-20 is needed for quick maneuvers over long distances; the main task of a medium tank is to break through defenses, for this purpose it has 45mm armor plates and a 76mm cannon. This is actually why the T-34s were lost in border battles due to lack of fuel; range and long crossings were not a priority.

                So what, as can be seen from the tests of the A-20, the chassis of the BT tanks, which was generally inherited from the Christie tank, was in fact incorrectly designed with gross miscalculations. But that’s not the point, the short service life of rubber bands is mentioned in the A-20 tests. So where is this apocalypse during the entire combat service of BT tanks, so that entire units “stopped” because their rubber bands “crumbled”? Where is this problem of such a small resource that it directly reduces the combat readiness of tanks, so that the military directly shouts and issues technical specifications, immediately solve the problem of a small resource!!! Before the A-20, no one really bothered.
                strange isn't it?

                Why always? The steered wheels on the A-20 traveled 4200 km without replacement, and on the A-32 3000 km were recorded. Which seems to say, the main thing is to maintain a balance of uniform load on the road wheels and not exceed the load limit for a specific rubber composition. The point of wheel travel is to double the fuel supply, preserve the service life of the tracks and abandon tank tractors with semi-trailers. The tracked tank went into production because the mass of the tank had increased sharply, which the wheel-tracked propulsion system of that time “could not bear”; for this it was necessary to install pneumatic tires, like on the Lorraine 40t. But they didn’t “go far” with purely tracked tanks. On the T-34-85 there was overheating of the front rollers due to the heavy turret, on the Sherman too, there’s no need to talk about “grooves” at all, they encountered this even earlier, so the Nazis “slipped” to chess “plates”.

                Imagine, instead of the A-20, the Mk.VII “Tetrarch” at maximum speed.

                Well, firstly, since the chassis of the BT tanks was initially poorly designed, during operation the wheeled-tracked propulsion unit did not impress the military, so there was no technical specification to “shove” this propulsion unit everywhere. And yes, there are fools around, armored vehicles, either with or without all-wheel drive, will still be inferior to a caterpillar in cross-country ability, the design of all-wheel drive is more complicated, the BT tank on wheels does not have all-wheel drive.
                There are half-track tractors, you get all the hemorrhoids with the cost and maintenance of the tracked propulsion system, especially the Natsiks, they also don’t have a double fuel supply.

                Look at the logic, if the cost of operating on tracks was lower than the short service life of rubber bands, the military would have abandoned the wheeled-tracked propulsion system a long time ago.
                1. 0
                  23 December 2023 06: 02
                  The missions for the T-60, T-70, T-80, SU-76, Mk.III “Valentine” and Mk.II “Matilda II” were virtually unchanged during the war years.

                  Only on the Valentines they installed 57-mm and 75-mm cannons for some reason, and on the T-80 they tested the more powerful VT-43 gun. In reality, for some reason they didn’t know that forty-five was enough.

                  Since the A-20 was abandoned, the T-34 took over its functions.

                  This is what I’ve been writing about from the very beginning: if you have a tracked tank with good speed, the A-20 is not needed.

                  This is actually why the T-34s were lost in border battles due to lack of fuel; range and long crossings were not a priority.

                  They were lost just like the BT-7M with a huge range.

                  So where is this apocalypse during the entire combat service of BT tanks, so that entire units “stopped” because their rubber bands “crumbled”?

                  Nowhere. We just barely rode on wheels.

                  The point of wheel travel is to double the fuel supply, preserve the service life of the tracks and abandon tank tractors with semi-trailers.

                  If you save the life of the tracks, but wear out the rollers, then you won’t get far. When you put on tracks, your roller resource is not magically reset to zero. The resource of the chassis is determined by the shortest service life of its parts. On the BT-7 you will kill the rollers before you run out of fuel.

                  Look at the logic, if the cost of operating on tracks was lower than the short service life of rubber bands, the military would have abandoned the wheeled-tracked propulsion system a long time ago.

                  So they refused, just not right away. Inertia of thinking is common.

                  Why always?

                  Read the article, it says.

                  The steered wheels on the A-20 traveled 4200 km without replacement

                  That's right, these are the lightest rollers. And the rest are on wheels and have not traveled thousands of kilometers. On the tracks, the rubber lasted 3000 km. You stubbornly do not want to understand that on wheels the service life of the tires is much lower, therefore the service life of the chassis is also lower. With the introduction of the synchronizer, the speeds on the tracks and wheels became equal, but you do not realize the increased power reserve on the wheels due to wear on the rollers.

                  The chassis of the BT tanks, which was generally inherited from the Christie tank, was in fact incorrectly designed with gross miscalculations.

                  Oh, so it's Christie's fault? And what did he do wrong? Just in case, I’ll explain that the American-made M1931 is not the same as the BT-2, which was Soviet-made and of Soviet quality. Their skating rinks are different.
                  1. 0
                    23 December 2023 13: 08
                    So again we are engaged in verbiage, the 57mm and 75mm guns on the Valentine were installed by the British to suit their needs, and the USSR bought what was offered to it for sale.
                    Well, closer to the middle of the war, they planned to install a slightly more powerful gun on the T-80 to support infantry and slightly better self-defense from armored vehicles.

                    SOLUTION
                    ABTU R.K.K.A. on TANK A-20.

                    The A-20 tank has great advantages over existing BT tanks in terms of its armor, engine, operational and combat qualities.
                    Plant No. 183 needs to produce a pilot batch of 15 pieces. by January 1.1.1940, XNUMX
                    Before launching the installation batch, eliminate all defects found during testing and strengthen the frontal plate to 25 mm, and the bottom in the bow to 15 mm.

                    I repeat once again, for those who are especially attentive, the main task of a medium tank is to break through the defense, which was done before by the T-28, and then by the T-34. A medium tank can also perform other tasks, but worse; the A-20 was most likely abandoned in order to produce more T-34s. By the end of the war, this led to the formation of reconnaissance platoons on T-34s or Pz.Kpfw. V Panther, because nothing more suitable was found.

                    There are statistics on how many BT-7Ms were lost precisely from the consumption of all the fuel, where is it?
                    If you have nothing, purely logically your opinion can be neglected.

                    Nowhere. We just barely rode on wheels.

                    That is, in the USSR they specially created a more expensive wheeled-tracked tank in order to save the life of the tracks, but did not use it on wheels, and after the BT-7M they still ordered to design a new wheeled-tracked tank from scratch!
                    Here, either the Soviet military were fools, which is not confirmed by the documents, or someone else, and I am inclined to the second option.

                    Instead of blah blah blah, the resource of the skating rinks is not magically reset to zero and other assumptions and theories, an example in the studio like here.
                    Tanker Dmitry Loza, in his book “Tankman on a Foreign Car,” told how during the Iasi-Kishinev operation, the Soviet tank corps stopped near Bucharest due to the fact that the Sherman tires could not withstand long marches during the heat and collapsed. It took the tank crews three days to replace and install new rollers.

                    BT tanks were not only in use from the beginning of the 30s and until the end of World War II, if the Far East is taken into account, but they also took an active part in hostilities. Here, instead of idle talk, the real fact is that the short life of rubber bands prevented some unit from using BT tanks.

                    The inertia of thinking of the Soviet military is impressive; since the early 30s, not only have they not abandoned the wheeled-tracked propulsion system, but they have also built a bunch of prototypes and ordered a new wheeled-tracked tank from scratch. Obviously in the USSR, with the operation of a wheeled-tracked propulsion system, everything was much better than with the competence of the author of this article in this matter.

                    The A-32 has five pairs of road wheels, and the A-20 has four pairs of road wheels, despite the fact that the latter is only 1t. easier. No one cared about the wear and tear of the rubber bands, it didn’t pose any problem, it’s just you running around shouting: low resource, low resource.
                    The tank passed 4200 km in factory and field tests.
                    During testing the following was revealed:
                    1. It is necessary to strengthen the onboard clutches and brakes.
                    2. Change the sloth mounting design.
                    3. Strengthen the wheel drive bearing.
                    4. Improve visibility from the tank by installing additional viewing devices.
                    The factory eliminates these shortcomings.

                    The tank passed 3000 km in factory and field tests.

                    That is, the A-32 traveled only 3000 km, and the A-20 covered 4200 km. At the same time, it can be noted that the A-20 spent most of its run both on tracks and on wheels on hard surfaces, but not on virgin soil at all, and the A-32 spent a smaller part on hard surfaces, and still on virgin soil. In addition, the A-20 was constantly setting all sorts of speed records, not paying attention to the wear and tear of the chassis.
                    So your theory, to put it mildly, requires additional testing.

                    In the second half of May and the first half of June 1931, numerous tests were carried out on the “Original I” and “Original II” tanks, which were indicated in the documentation as BT-1. They showed that the tank required serious modifications - its gearbox overheated, the chassis could not withstand the loads, and the front double-leaf hatch of a complex configuration was inconvenient. In addition, it was necessary to re-create the turret, which was never delivered from the United States, and equip it with sufficiently powerful artillery weapons.

                    The American quality was also not impressive, and what about the fact that the road wheels are different? Couldn’t you measure the diameter and width of the rollers with a tape measure?
                    1. 0
                      23 December 2023 16: 14
                      and that the support rollers are different, were you unable to measure the diameter and width of the rollers with a tape measure?

                      The Original's rollers covered 1000 km without serious problems. On BT-2 they quickly fell. Soviet rubber was of lower quality, and the inability to repeat Christie's design led to the fact that Soviet rollers made the tank 800 kg heavier. The chassis really couldn't stand it - the sloth broke. It has nothing to do with what we are discussing.

                      There are statistics on how many BT-7Ms were lost precisely from the consumption of all the fuel, where is it?

                      You didn't understand what I wrote at all.

                      The A-20 was most likely abandoned in order to produce more T-34s.

                      What kind of fortune telling is this? The A-20 was abandoned even before the T-34 appeared based on test results. The A-20 was initially created in two versions, wheeled-tracked and purely tracked, in order to choose the best one based on test results. Then the tracked A-20 was converted into an A-32 and built in this form.

                      That is, in the USSR they specially created a more expensive wheeled-tracked tank

                      They did not create, but took an almost ready-made, raw chassis, which was created under the leadership of a purely civilian engineer, who more than once waved his hand at the wishes of the military. And then they produced it without radical changes, even when the wheel drive became completely useless.

                      General Pavlov said directly: “If you need a point of view for the army - which tank is better, wheeled-tracked or tracked, I will answer this way - all over Europe they abandoned wheeled-tracked vehicles for two reasons - they are difficult to manufacture, difficult to repair and restore, and not provides special benefits."

                      He also: “There must be one tank intended for operations with infantry (cavalry) and as part of independent tank formations.
                      To achieve this goal, it is necessary to develop two types of tank, one purely tracked and the other wheeled and tracked. Comprehensively test them during 1939 and then put them into service, replacing the BT and T-26 tanks with the one that meets all the requirements."

                      And one more thing: “Upon receiving the chassis (including the caterpillar) of a purely tracked tank, operating for at least 3000 km, it will be possible to abandon the wheeled-tracked type of tank.”

                      Hence the same 3000 km that the A-32 traveled, and its rollers could continue to work. A-20 traveled more because 1). it was built before 2). tested not only tracked, but also wheeled travel and 3). on the A-32 there were two serious fan failures, once it flew apart, breaking radiators, rods, tanks, etc. During this time, the A-20 has covered hundreds of kilometers.

                      Instead of blah blah blah, the resource of the skating rinks is not magically reset to zero and other assumptions and theories, an example in the studio like here.

                      And what does this example show, besides the fact that Sherman had a mediocre chassis?
                      1. 0
                        24 December 2023 19: 20
                        How did the “Original” travel 1000 km on tracks or on wheels? Then there are questions about this tank, whose outer road wheels have rubber tires with perforations, but the inner ones do not.
                        Very often, rubber bands fell off the guide and drive wheels of the caterpillar tracks; due to poor fit and welding, the ill-fated brackets of the guide wheels broke and the welds of the exhaust manifolds came apart.

                        So the rubber bands on the BT-2 did not collapse due to wear, but simply “flew off”, and then this problem was eliminated.
                        Two types of rollers were used on the vehicle: cast disks with holes and “spoked” ones, as well as solid stamped disks, which were installed on BT-2 tanks after mass production of the BT-5 tank was organized during repairs.

                        KhPZ could not immediately install stamped wheels, like on Christie, so they had to install cast ones, which made the tank heavier by 800 kg.
                        We are trying to twist the facts to prove our failed theory about wheeled-tracked tanks, but something went wrong, right?)))

                        What else do I need to understand, you stated here that the BT-7Ms, with their huge supply of fuel on wheels, were just as lost as the T-34s with their small supply of fuel. The question arises, why such loud statements, there was no answer, therefore, are you deliberately lying?

                        Regarding the production of the A-20 tank, the draft resolution provided for the following:

                        "1. Organize a production base for the manufacture of the A-20 tank and hulls for them at plant No. 183 NKSM, setting the following production dates:
                        A. 10 samples of the serial standard for 1.V.1940.
                        B. Prepare serial production of A-20 tanks by 1.VIII by releasing 1940 serial tanks in 300.
                        The production capacity of A-20 tanks for plant No. 183 should be set at 1500 units. for 1941 and 2500 pcs. for 1942
                        2. NKSP comrade. TEVOSYAN organizes the production of armor (hulls, turrets and armored parts) for A-20 vehicles at the Mariupol plant.
                        3. Oblige the NKSP for the A-20 tank to ensure the supply of armor to plant No. 183 NKSM within the following time frames:
                        by January 1.1.1940, 3 in the amount of XNUMX sets,
                        by March 1.3.1940, 7 in the amount of XNUMX sets and the rest according to the schedule of the NKSM and NKSP.
                        NKSP comrade TEVOSYAN to prepare the production of armor for the A-20 from 1.VIII.1940 with the supply of 1940 sets in 350, 1941 sets of hulls in 1600, 1942 sets of hulls in 2750.”

                        Lies, lies, lies.
                        Of course, I understand that we should extol the “crafts” of the Third Reich in every possible way, and try to belittle what was Soviet, but maybe we shouldn’t work so rudely.
                        The A-20 was not sent into production, but not based on the results of field tests, but in May 1940. after Poland and the Soviet-Finnish.
                        "1. Clause 5 §§ a, b, c, d of the Resolution of the Defense Committee No. 191ss of May 4 this year - cancel.
                        2. Manufactured by industry, but not meeting all the latest tactical and technical requirements: for example, the A-20 is wheeled and tracked with a B-2 diesel engine and three pairs of drive wheels; breakthrough tanks T-100 and SMK; LB-23 armored vehicle, not put into production.
                        3. In order to study and generalize the experience of tank building by plant designers and improve tank equipment, prototypes with all the drawings and technical specifications should be transferred to the ABTU Red Army Scientific Research Polygon.”


                        This is all very interesting, of course, but I will quote from Pavlov’s report to Voroshilov
                        While maintaining the interchangeability of the BT-8 chassis with the existing BT-7 tank, strengthen the BT-8 chassis so that it is not inferior in strength to the BT-7. This can be solved most simply and quickly, and does not require fundamental alterations in the tank, but with this solution to the issue, wheeled-tracked tanks, due to the weakness of the rubber, essentially turn into tracked tanks. This situation is clearly not tolerable and can only be tolerated as a temporary measure in anticipation of the transition to a new type, currently being developed at Plant No. 183, the BT-20 tank.

                        I will once again repeat Pavlov’s decision on September 15, 1939.
                        SOLUTION
                        ABTU R.K.K.A. on TANK A-20.

                        The A-20 tank has great advantages over existing BT tanks in terms of its armor, engine, operational and combat qualities.
                        Plant No. 183 needs to produce a pilot batch of 15 pieces. by January 1.1.1940, XNUMX
                        Before launching the installation batch, eliminate all defects found during testing and strengthen the frontal plate to 25 mm, and the bottom in the bow to 15 mm.
                        HEAD OF ABTU RKKA KOMCOR signature (PAVLOV)

                        MILITARY COMMISSIONER ABTU RKKA BRIGADE COMMISSIONER signature (KULIKOV)

                        "15" September 1939

                        On the A-20, the steered wheels traveled 4200 km and could also be used further.
                        What pathetic excuses were there, the A-20 and A-32 were undergoing field tests at the same time. The A-20 was tested on tracks and wheels, so it traveled more, but this is discrimination against the A-32, this cannot be tolerated))))

                        This example shows that you cannot write articles about armored vehicles, since your knowledge “floats” at the level of a schoolchild sitting on Wikipedia, or thematic forums and retelling old myths.
                        For some reason I easily found an example of the real combat use of BT-2 tanks
                        During numerous marches, only one engine and three gearboxes failed. The personnel of the regiment, led by Colonel Starkov, were taken prisoner: one general, 68 colonels and lieutenant colonels, over 600 officers and 2866 soldiers. Captured: 2 tanks, 4 guns, 950 pistols and 168 horses with saddles.
                        During the voyage, the tank engines worked from 125 to 225 engine hours. To restore the material part, the regiment received seven engines, three gearboxes, and ten drive and guide wheels. In addition, 3000 tracks required replacement.

                        In total, the tanks are not the first freshness, due to the short service life of the tracks and the equally short service life of the rubber bands, according to you, in theory they should have left their chassis in Poland, but this did not happen.
                        If the Sherman has a mediocre chassis, then what can we say about the chassis of the 3rd and 4th “grooves”.

                        1. To have in the Red Army, instead of the existing tank corps and separate tank brigades, the same type of organization of separate tank brigades, the same type of organization of separate BT and T-26 tank brigades consisting of four tank battalions, armed with T-26 and BT tanks with further rearmament with tanks T-34. Tank brigades T-28 and T-35, with further rearmament with KV tanks, will have a three-battal composition.

                        We couldn’t achieve the same type, we still had to create the T-34 and other “riffraff” in addition to the T-50
                      2. 0
                        24 December 2023 20: 24
                        You are a very boring conversationalist, because every year you mirror me every year. I initially started from the documents on T34inform and you started throwing quotes from there. I brought Pavlov and you posted Pavlov in response. And so every discussion.

                        That is, you simply follow the target of criticism and at every step try to show that you are able to work with sources better, that your logic and understanding are more correct. If you have such complexes, why not start writing articles? And why were you laughed at on LiveJournal, and dozens of comments were deleted and banned on Warspot?

                        You started this criticism without even understanding that without tracks, rollers last less and why this happens. And now “Lies, lies, lies”, you are still lying (c). In general, I leave you alone with your psycho-emotional state.
                      3. 0
                        25 December 2023 17: 17
                        Imagine, I do your work for you, and oddly enough, better, despite the fact that I did not specifically study this topic at all. You simply limited yourself to the slogan “short service life of rubber tires on wheels, so they abandoned wheeled-tracked tanks”, the case is closed, we all part ways.
                        If we begin to study this issue more closely, it turns out that the short life of rubber bands did not bother anyone in principle, right up to the BT-7M.

                        When the A-20 and A-32 successfully passed field tests, Pavlov, as the head of the ABTU, personally recommended the A-20 for mass production as a replacement for BT tanks. This is the Pavlov who “beat himself in the chest with his heel”, saying: yes, wheeled-tracked tanks are being abandoned, but we only need one type of tank based on the results of tests.
                        I consider it possible from the T-26 class of vehicles from 1941, i.e. from the moment of mass serial production of the T-32 at the STZ plant - to abandon, stopping further development of the production of T-26, replacing completely existing brands of vehicles with new brands: T-20 replaces BT, T-32 - T-26 and T-28, and heavy vehicles of the KV type with a diesel engine, and if the SMK and 100 are adopted, the Red Army will be in service as a new class of vehicles.”


                        As a result, the A-20 was not put into mass production due to “undercover squabbling” between the factories and the government.
                        Plant No. 174 and Ginzburg did not want to produce the A-34, instead of their “darling” T-26. Plant No. 183 abandoned the A-20 in favor of the “simpler” A-34. The result of the “war” of the factories was that in November the main military council of the Red Army decided to replace the 26-ton BT-34M and the 28-ton T-14 with the 7-ton T-10 (the same weight as the T-26).

                        Then, after the capture of the “Polish” 3rd groove, it suddenly turns out that there is no new type of light tank in the USSR!!! And then Ginzburg, after the closure of production of the T-26 and numerous unsuccessful attempts to replace it, “gives birth” to the T-50. Which, as a replacement for the T-26, is not bad, but it does not “fit” as a high-speed tank, with its small rollers with internal shock absorption, a modest power reserve and without any prospects for modernization. Not to mention the fact that this type of mass-produced light tank actually has no unification with other tanks, which means it will not cost like a “cast iron bridge”, but cheaper.

                        This is what should have been “written” in the article, and not indulged in graphomania, like some schoolboy who publishes his “hat” on all sorts of Internet resources.
                        I don’t have any complexes, but when someone with a smart look “rubs the game” into me, I don’t like it and it’s very upsetting. And you, as I see it, “put on the crown”, you consider yourself an expert in armored vehicles, I have sad news for you - this is not so. Let's call you the Great Compiler)))
                        I don’t sit on LiveJournal, but Warspot has moderators with “watchman syndrome”.

                        By the way, everything is fine with you, otherwise I’m worried about your mental health, you constantly talk about rollers without tracks, repeating the same thing over and over again, it’s unclear in the hope of what...
            2. 0
              22 December 2023 15: 14
              Quote: bushmaster
              The A-20 has a much higher service life of rubber tires than the BT-7, and since the BT series tanks were actively used throughout the 30s and early 40s, for some reason they noticed breaking gearboxes on BT series tanks, and with road wheels suddenly no apocalypse happened.


              Where did you get the idea that “The A-20 has a much higher service life of rubber bands than the BT-7.” It's not a matter of design, but the quality of the rubber. The USSR had problems with the production of high-quality rubber. Synthetic rubber has lower mechanical strength, while natural rubber is “afraid” of petroleum products. To produce rubber for cars and tanks, it was necessary to mix synthetic and natural rubber. But the USSR had problems with natural products. The low quality of rubber was a problem for vehicles and even for aviation.
              That is why tanks of the BT series have practically not moved on wheels since the late 30s.
              1. +1
                23 December 2023 13: 16
                Read tests A-20 and A-32
                Rubber on wheels at an ambient temperature of 25 - 30˚ with an average pure speed of 40 km/h with continuous movement from 25 to 100 km. worked for 700 km until it was destroyed. along a crushed stone highway and 400 km. on a dirt road, whereas the A-7 [BT-7] under the same conditions costs 50 - 100 km. On caterpillar tracks, the tires lasted 3000 km.
                The increase in rubber durability of the A-20 tank was achieved due to a more uniform load on the wheels, 1,5˚ wheel camber and widening of the rubber band. The relationship between the increase in rubber resistance between wheel camber and tire widening could not be established due to the lack of rubber. The camber justified its purpose and its use on wheeled-tracked models is mandatory.”

                https://t34inform.ru/publication/p01-9.html
  11. +2
    21 December 2023 16: 50
    Quote: Amateur
    2. What kind of truck from the 20s of the 6th century could carry 1 tons of cargo (MS-18, while the T-5.9 weighed XNUMX tons)?


    Berlie NVA
    Bernard DI6C
    Chenard-Walker FAR
    Dewald K3
    Delae-80
    Latil TAR (all-wheel drive)
    Pierce-Arrow R8
    Renault EG
    Renault FU
    Saurer B
    Schneider CD

    This does not take into account Britain, Italians and other small creatures.
  12. 0
    21 December 2023 19: 55
    So what? For the concept of that war, the transmission was quite enough: 1) to quickly reach a European country on wheels 2) to die heroically on tracks (how long does a tank live on the battlefield?) in the very first attacks, ensuring advancement, success and victory.
    1. +1
      21 December 2023 21: 41
      Quote: STUG III
      For the concept of that war, the transmission was quite enough: 1

      Rather, the peak of his career would have been in Africa, in operations on German communications in the desert and in service with the cavalry of the Red Army and China. Even now, wheeled tanks and self-propelled guns are being built for the African region.
      On the other hand, with the intensification of counter-battery warfare, many modern self-propelled guns may return to wheels and a complex transmission.
    2. -1
      22 December 2023 04: 45
      quickly reach a European country on wheels

      You will wear out the rubber bands, and then get up to inspect and service the chassis. If the rollers need to be replaced, you won't get very far with tracks.

      This misconception about wheels arose because not everyone understood: the life of the chassis is determined by the shortest life of its weakest elements. When you raced on wheels and spent the resource of the tires, you cannot put on the tracks by magically “resetting” the resource of the rollers.
      1. 0
        23 December 2023 16: 30
        Quote from: geraet4501
        When you raced on wheels and spent the resource of the tires, you cannot put on the tracks by magically “resetting” the resource of the rollers.

        If the rollers have double shock absorption, external and internal, the service life will be unchanged, only the noise will be stronger.
        A very simple all-metal roller has a speed limit, although it is not afraid of wear.
        1. 0
          23 December 2023 16: 37
          An all-metal roller will kill the tracks faster. A steel rim with internal shock absorption won't be much better.
          1. 0
            23 December 2023 18: 27
            A bare roller on a caterpillar will move less overall and at slower speeds, so there will be an overall favorable balance of timing of different modes of movement. On slow tractors, non-rubber rollers are quite common.
  13. +2
    22 December 2023 12: 35
    It’s interesting that the review doesn’t say a word about reliability in combat, maintainability of complex mechanisms after damage, or repairs in the field. But tanks must not only ride, but also fight...
  14. 0
    23 December 2023 02: 53
    You should not confuse the Christie suspension with the wheel-tracked drive, although both crossed paths on BT tanks. The Christie suspension was mass-produced on the BT, T-34 and English “cruisers”, and almost everyone from the Americans to the Japanese tried it. By the way, the founders themselves, the Americans, considered the Christie pendant unsuccessful and outdated, they never used it in series and were surprised at its popularity in Britain and the USSR.
    1. 0
      23 December 2023 05: 39
      And who is confused?

      the founders themselves, the Americans, considered the Christie pendant unsuccessful and outdated, they never used it in series and were surprised at its popularity in Britain and the USSR

      Not everything was all right with them either. The rubber bands on the Shermans quickly flew, the tracks with rubber cushions had lousy grip, and overcoming vertical obstacles was not very good. In terms of cross-country ability, the Panther was much better than the Shermans; comparative tests in Germany and Sweden proved this.

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