Having completed the description of the battleships "Pennsylvania", "Rivendzh" and "Baden", as well as having considered the capabilities of their main caliber, we finally got the opportunity to move on to comparing these ships. Let's start, of course, with the "big guns".
Main artillery
In the last article on armor penetration, we came to a rather unexpected conclusion: despite the smaller caliber, the American 356-mm / 45 artillery system, which armed the battleships "Pennsylvania", was in no way inferior to the 381-mm / 42 and 380- mm / 45 guns of the English and German battleships. Apparently, the ballistic qualities of the American projectile turned out to be higher, also due to the smaller caliber - the American projectile had a cross-sectional area about 15% less than the ammunition of the British and German superdreadnoughts, and it is clear that the larger the caliber of the projectile, the greater the resistance the projectile is forced to overcome.
According to the calculations of the author of this article, the American 356-mm projectile weighing 635 kg with an initial speed of 792 m / s had better flatness in comparison with the German and British fifteen-inch projectiles. This had its advantages … but also very significant disadvantages. However, let's talk about the good first.
Obviously, a projectile fired into a vertically located armor plate from a certain distance will hit it at a certain angle to the surface of the plate. Still, the force of gravity has not been canceled, so that the projectile does not fly in a straight line, but in a parabola. And it is clear that the greater the angle of incidence of the projectile, the more difficult it is for him to penetrate the armor, since he has to "pave" a larger path in this armor. Therefore, any formula for armor penetration necessarily takes into account the angle at which the projectile hit the armor plate.
However, the angle at which the projectile hits the target, of course, depends not only on the angle of fall of the projectile, but also on the position of the armor plate in space - after all, it, for example, can be deployed obliquely with respect to the trajectory of the projectile.
Thus, in addition to the angle of incidence (angle A, vertical plane), it is also necessary to take into account the position of the armor plate itself (angle B, horizontal plane). Obviously, the angle at which the projectile hits the armor will be affected by both angle A and angle B.
So, taking into account all of the above, the weakest predictably turned out to be the 330 mm Rivendz belt. In a duel against Bayern, Rivenge will penetrate the opponent's 350 mm armor belt from a distance of 75 cables at a course angle of no more than 18 degrees. At the same time, at the same distance, the Bayern is capable of penetrating the Rivendzha's main armor belt at a heading angle of up to 22.3 degrees. Belt "Pennsylvania" 343 mm thick "Rivenge" breaks through at a course angle of 20, 4 degrees., Itself "breaks through" at 25 degrees.
The second place is occupied by Bayern - it, as we saw above, is slightly superior to Rivenge (22, 4 deg. Versus 18 deg.), But, in turn, is also inferior to Pennsylvania. "The brainchild of a gloomy Teutonic genius" pierces the 343 mm belt of the American battleship at heading angles up to 18, 2 degrees, and itself breaks through at 19, 3 degrees.
So, the first place belongs to the American battleship "Pennsylvania", but … you need to understand that in battle such an advantage (1-5 degrees) will not have any practical value. Simply put, it is impossible to find the tactics to take advantage of such a slight advantage.
Thus, although, in theory, we should give the palm to the American battleship, the practical conclusion will be as follows - at a distance of 75 cables when conducting a classic battle in parallel wake columns, "everyone penetrates everyone," that is, the armored belts of Pennsylvania, Bayern and Rivendzha”do not protect against shells from other battleships.
But the armor belt is not the only protection of the battleship. So, for example, the Rivendzha's 330 mm belt was followed by a 50.8 mm bevel located at an angle of 45 degrees. mm anti-torpedo bulkhead. At Bayern, everything was also very thorough - behind the 350 mm belt there was a 30 mm bevel located at an angle of 20 degrees. to the surface of the sea, and behind it - also a vertical 50 mm bulkhead. Actually, the same could "boast" and "Pennsylvania" - for the 343 mm armor belt there was a bevel, representing the armor plate on the deck flooring of ordinary steel, their total thickness was 49, 8 mm. And behind it there was still a powerful anti-torpedo bulkhead with a thickness of 74, 7 mm!
Nevertheless, the calculation according to the corresponding formula for uncemented armor up to 75 mm (which was given in the previous article) shows that all this protection will be penetrated if the shell hits the ship at an angle close to ideal (that is, approximately equal to the angle of incidence of the projectile). In this case, for example, the British 381-mm projectile, after overcoming the 343 m of the Pennsylvania armor belt, will still maintain a speed of about 167 m / s, which in theory was quite enough for two thin sheets of homogeneous armor.
Just do not forget that such ideal conditions in a real battle can develop only by accident. Even if both sides want a correct battle, and this does not always happen, often as a result of maneuvering it turns out that the enemy appears to be on a parallel course, but behind or ahead of the traverse. And the courses themselves are rarely absolutely parallel: it is not so easy to determine the exact direction of an enemy ship at a long distance, and besides, ships also maneuver, periodically changing course, and moving like a broken line in order to knock down the enemy's sight.
And therefore, rather, the conclusion should be made as follows: despite the fact that under certain ideal conditions, 356-381-mm shells are indeed capable of penetrating cellars, engine rooms or boiler rooms of Rivenge, Bayern and Pennsylvania, in reality there are it is almost not. It is to be expected that British, American and German shells will penetrate the main armor belts at the limit of their capabilities, almost completely wasting their energy. As you know, the armor-piercing action of the projectile (which has overcome the armor as a whole) is made up of its "manpower", since a heavy ammunition flying at a speed of tens, or even hundreds of meters per second, has a great destructive ability, and in addition - the force of its rupture … So, we should assume that after the breakdown of the armor belt, the first damaging factor will be insignificant, and it is the shell burst that will cause the main damage to the ship.
This, in turn, leads us to the fact that the damage behind the armored belt of battleships will depend primarily on the bursting force of the shell, and on the number of shells hitting the target. And here, it would seem, the palm should again be given to "Pennsylvania" - well, of course, because she has 12 guns, while the rest of the battleships have only 8, therefore, it is the American battleship that has the most chances to provide the greatest number of hits in enemy. However, this is not at all the case.
First, too good ballistics starts to make itself felt here. It is generally believed that high flatness provides the best accuracy, but this is still true only up to certain limits. The fact is that at a distance of 75 cables, a vertical guidance error of only 0.1 degree leads to a change in the height of the trajectory by 24 m, while the American projectile will fly 133 m further than necessary. For the English 381-mm gun, this figure is 103 m.
The second is the placement of the guns of American turret installations in one cradle, which is why the shells were strongly affected by gases escaping from neighboring barrels. There were even cases of collisions of shells in flight.
All this led to the fact that, despite the presence of 12 guns in the salvo, the accuracy of the hits did not boggle the imagination at all. As we saw on the example of the shooting of the "Nevada" and "New York", after covering the target, American battleships achieved 1-2 hits in a volley, more often two than one. Of course, "Pennsylvania" had 12 guns, not 10, but this could hardly give a big gain in comparison with the 10-gun American battleships listed above. Still, the "Nevada" had 4 guns, and the "New York" all 10 were located in quite adequate turrets, with guns in different cradles and a relatively large distance between the barrels. Perhaps one can even assume that the 12-gun salvo of the Pennsylvania could be less accurate than the 10-gun salvo of the Nevada, although, of course, there is no evidence of this.
Upon completion of the zeroing, European battleships usually achieved one, rarely two hits in a salvo (and not in training, but in battle), but - firing four-gun salvoes, which they could fire about twice as fast as the Americans - their 12-gun ones. Thus, the greater number of barrels in the salvo was leveled out by less accuracy, and it turned out that the American battleship per unit of time brought in about the same number of shells into the target as the 8-gun European. And maybe even less.
But that would be half the trouble, and the real problem was that we are talking about the results of the post-war shooting. The fact is that after the joint service of American and British battleships at the end of the First World War, and according to the results of joint exercises conducted during this service, the American admirals found that the dispersion of shells in the salvoes of their ships was excessively large compared to the British ones. As a result, work was immediately initiated to reduce the scattering, and it was halved in the early 1920s. That is, their own, and I must say, not amazing accuracy, "Nevada" and "New York" showed only after a significant reduction in dispersion. And the Americans achieved this, including by reducing the muzzle velocity of the projectile.
Unfortunately, the author of this article could not find information on how exactly the Americans reduced the muzzle velocity of their 356-mm projectiles. But it is obvious that, no matter how much they reduced, this measure made it possible to improve accuracy at the expense of armor penetration.
And so it turns out that the American 356-mm cannon, housed in the "proprietary" American three-gun mount, at a distance of 75 cables and with a passport muzzle velocity of 792 m / s, fully matched the armor penetration of the German and British fifteen-inch artillery systems. But at the same time, she was greatly inferior to them in accuracy, and so much so that even the "12-gun" battleship of the United States could not bring into the target as many shells per unit of time as the 8-cannon European ones could.
And the increase in accuracy led to the loss of armor penetration. Unfortunately, we don't know how much. The calculations made by the author show that with a decrease in the initial speed of a 635-kg American projectile by 50 m / s, its angle of incidence by 75 cables will be 12.51 degrees, and thereby approaching the same indicator of the British 381-mm / 42 artillery system (13.05 deg). But at the same time, the armor penetration drops from 380 to 340 mm - in other words, in order to ensure acceptable accuracy in only one factor (the angle of incidence), the Pennsylvania should “say goodbye” to the ability to penetrate the 350 mm armor belt of the Bayern at a distance of 75 cables. She will be able to pierce the 330 mm armor belt of the Rivendzha only “on big holidays”, when conditions are close to ideal.
And if we add to this the small mechanization of American towers, in which, for example, heavy gunpowder caps, the crews had to turn over and send them by hand?
But that's not all. Let's now compare the power of the 356 mm, 380 mm and 381 mm shells of the American, German and British battleships. The pre-Utland British projectile could boast of the highest explosive content - it contained 27.4 kg of liddite. But alas, he showed completely insufficient armor penetration, which is why such ammunition gave way to armor-piercing shells created under the Greenboy program in the cellars of British battleships. And for those, the content of explosives in armor-piercing shells was much more modest - 20, 5 kg, however, not liddite, but shellite.
Thus, the undoubted leader in terms of the power of an armor-piercing projectile is the German Bayern, whose ammunition contained 23 kg (according to other sources - 25 kg) TNT. True, it would be nice to compare the power of trinitrotoluene and shellite here, but alas, this is much more difficult than a simple comparison of blasting rates taken from reference books. Without claiming the absolute accuracy of his estimate, the author would venture to assert that if shellite exceeded trinitrotoluene, then by no more than 10%, but rather still somewhat less, about 8%. Thus, the "excess" power of the British shellite ammunition still did not compensate for the increased content of explosives in the German projectile.
The honorable second place is taken by the British 381-mm "greenboy" with the already mentioned 20, 5 kg of explosives. But in third place, predictably, there were 356-mm armor-piercing shells "Pennsylvania" with their 13, 4 kg of explosives. At the same time, he draws attention to the fact that the Americans used, apparently, the weakest explosives: Explosive D, with which they equipped their ammunition, had a TNT equivalent of 0.95. at 55, 3% of the power of the German 380-mm and probably 57, 5% of the power of the English 381-mm projectile.
I would like to note that the indicator of the mass of explosives, which the ship is able to "bring" to its rival for the armor belt, looks quite important when comparing the combat capabilities of ships. So, according to this indicator, the American battleship, in comparison with the European ones, looks like a uniform outsider. By reducing the initial velocity of the projectiles, it is possible to provide Pennsylvania with an equal number of hits on the target with European battleships. But the penetration of American shells will be lower, which means that with an equal number of hits for armor, fewer of them will pass. And given that the power of the 356-mm projectile of the United States is only 55-57% of the British and German, we can say that even with the best assumptions, the artillery of "Pennsylvania" in a duel situation will be able to make no more than 40-45 % of the mass of explosives received "in response" from their European "opponent".
Thus, in terms of the aggregate combat qualities, the artillery of the German battleship Bayern should be considered the best.
This does not mean, of course, that the 380-mm / 45 German artillery system was superior in all respects to the 381-mm / 42 gun of the British. They, by and large, had quite comparable capabilities. But we are not comparing the artillery system itself, but the "cannon on the ship" and taking into account the somewhat better protection of the "Bayern", its quite comparable, in general, guns gave, nevertheless, some advantage to the German battleship.
Second place, of course, goes to the guns of the British battleship Rivenge. And in last place we have "Pennsylvania" - despite the 1.5 superiority in the number of barrels and high armor penetration of 356-mm guns.
Here, however, the dear reader may have two questions, and the first of them is this: why, in fact, when analyzing the armor penetration of battleships, we looked only at the armor belt, while ignoring the horizontal protection? The answer is very simple - as follows from the previous article, the author does not have any reliable mathematical apparatus in order to calculate the armor penetration of horizontal armor at a distance of 75 cables for the compared guns. Consequently, it is impossible to make calculations, and, alas, there are no detailed statistics on the actual shooting either.
Only theoretical considerations of the most general nature remain. In general, all other things being equal, the projectile penetrates the armored deck the better, the greater the angle of its incidence and the greater the mass of the projectile itself. From this point of view, the best of all, of course, looks like the British 381-mm gun with its angle of incidence of 13.05 degrees for 75 cables, the German one almost does not lag behind it (12.42 degrees) and in third place is the American artillery system with 10, 82 hail. But then the nuances begin.
The position of the American cannon begins to improve markedly with a decrease in the muzzle velocity. In this case, we can say that the Americans, by reducing this speed, and thereby sacrificing the armor penetration of vertical barriers, not only achieved an advantage in accuracy, but also received a gain in the armor penetration of the decks of their targets. Nevertheless, from the above example, we see that even with a speed reduced by 50 m / s, the American projectile, calculated, had practically the same angle of incidence as the German 380-mm / 45 gun - 12.51 degrees, but however, he still had a smaller mass. Thus, it can be stated that the American gun was in any case inferior to the German, and, moreover, the British artillery system, in terms of the effectiveness of penetrating the horizontal protection. Of course, we cannot exclude the fact that the muzzle velocity of 356-mm American projectiles was reduced by more than 50 m / s, and in this case, we should expect that its effectiveness when exposed to horizontal armor will increase, reaching, otherwise and slightly exceeding the capabilities of the English and German guns. But then its armor penetration of the vertical protection will finally "slide down", and the "Pennsylvania" will no longer be able to penetrate the armor belt of not only the Bayern, but also the Rivenge at a distance of 75 cables.
In other words, for any conceivable change in initial speeds, in terms of the aggregate combat qualities, the American gun still firmly takes the last place.
At the same time, the slight superiority of the British artillery system is largely offset by such a very interesting physical process as the normalization of the projectile trajectory when overcoming armor protection. In other words, the projectile, striking the armor plate at a certain angle, tends to "turn around" in the direction of least resistance when it passes, that is, to approach the normal and pass the plate perpendicular to its surface.
At the same time, as mentioned earlier, we are still not comparing the guns themselves, but the guns as part of a warship. So, both Bayern and Rivenge have armor protection arranged in such a way that in order to get to the armored deck, it is necessary to break through the armor protection of the ship's side. Obviously, in this case, both the 380-mm German and 381-mm British shells will undergo normalization and hit the armored deck at a significantly lower angle than the angle of incidence before "interaction" with the side armor.
In such conditions, most likely, it is no longer necessary to count on armor penetration, and even if a projectile hits the deck, it will not pierce it, but will explode directly on it or above it (in the event of a ricochet). Then the main damaging factor again becomes the explosion of the projectile, that is, the content of explosives in it, and here the German projectile is in the lead.
In other words, although we cannot say this for sure, but still theoretical reasoning leads us to the fact that in a hypothetical duel of the battleships we have chosen for comparison, from the point of view of the impact on the horizontal defense, the German and British guns are approximately equal, perhaps for a small the advantage of the German, and the American is an outsider. Consequently, the main caliber of the Bayern still remains in the first place, the Rivenge is in the second and the Pennsylvania, alas, takes the third place of little honor.
The second question of a respected reader will probably sound like this: “Why, when comparing the capabilities of artillery systems, only the main belts of battleships were taken? But what about their towers, barbets, conning towers and others? " The answer will be as follows: in the opinion of the author of this article, these questions are still more related to the protection systems of "Pennsylvania", "Rivenge" and "Bayern", and we will consider them in the corresponding article.
