Many English-speaking, and after them domestic experts, call the Iowa-class battleships the most advanced ships that were created in the era of armor and artillery. American designers and engineers managed to achieve a harmonious combination of the main combat characteristics - protection, travel speed and weapons. Let's try to figure out if this is so.
A lot of all sorts of tales have been written about the booking system for Iowa-class battleships. Which, in general, is not surprising: the ships were designed after the outbreak of World War II, and the Americans did not seek to reveal their true characteristics. And the information that leaked into the press was often clear misinformation. Moreover, if the Japanese had a tendency to diminish the combat capabilities of their ships (they say, let their power be a surprise to the enemy), then the Americans did the opposite ("so they were afraid!"). Therefore, according to many reputable reference books and monographs, the absolutely fantastic thickness of the Iowa's armor belt of 457 mm “walked” for a long time - one and a half times more than in reality. According to data declassified after 60 years, the Iowa's armor protection was almost exactly the same as that used on its predecessors, the South Dakota-class battleships. The main armor belt with a thickness of 307 mm (!) Was located inside the hull between the second and third decks and had a slope of 19 ° outward.
It was made of "Class A" armor (cemented, with a hard outer surface and a viscous inner). The height of the belt was 3.2 m. Theoretically, when meeting with a projectile flying strictly horizontally, the inclined armor belt was equivalent to a vertical thickness of 343 mm. At large angles of incidence of shells, the effectiveness of the Iowa's belt armor increased sharply, but the probability of hitting the belt became low. An inclined armor belt increases the armor resistance in proportion to the decrease in the area of protection. The greater the deviation of the trajectory of the projectile from the normal, the more protection the inclined armor belt gives, but the smaller the area (!) This same armor belt covers.
But this is not the only drawback of the inclined armor belt. The fact is that already at a distance of 100 cab. the deviation of the projectile from the normal (ie the angle of the projectile relative to the water surface) of the main guns of the WWII battleships is from 12 to 17.8 degrees (Kofman has a wonderful tablet in the book "Japanese battleships Yamato, Musashi" on page 124). At a distance of 150 cables, these angles increase to 23, 5-34, 9 degrees. Add to this another 19 degrees of inclination of the armor belt (South Dakota) - we get 31-36, 8 degrees for 100 cables and 42, 5-53, 9 degrees for 150 cables. It turns out that the inclined armor belt, located at an angle of 19 degrees, practically guaranteed that the projectile would split or ricochet at a distance of 100 cables (18.5 km). If it suddenly breaks, good, but if there is a ricochet? The fuse may well be charged from a strong glancing blow. Then the projectile will "slide" along the armor belt and go straight down through the PTZ, where it will fully explode under the bottom of the ship.
There are a lot of publications that say that the internal arrangement of the armor on the Iowas served to destroy (“remove”) the armor-piercing (“Makarov”) projectile tip, which increases the armor resistance of the protection. However, in the well-known documents on the design of aircraft types "South Dakota" and "Iowa" there is nothing to assert that the designers deliberately used the spaced reservation scheme and took into account the destruction of the armor-piercing tip of the enemy shell by the outer skin of the side.
The design of the Iowa-class battleships was carried out in the absence of contractual restrictions, however, the head of the General Council of the US Navy, Admiral Thomas Hart, for internal political reasons, obliged the designers of the new ship to try not to overestimate the displacement, which, given the very high requirements for weapons and speed, clearly meant savings on booking. So the American shipbuilders simply repeated the existing technical solution and reproduced the South Dakota booking scheme on Iowa with minor modifications. And the same S. A. Balakin in the monograph "Battleships of the" Iowa "type does not in any way note the special role of the outer side plating.
It turns out that the internal location of the side armor belt was used on these two types of ships for reasons of reducing the weight of armor and, as a result, displacement, and there was no question of "removing the armor-piercing caps" of the shells. By the way, the Italians, who were the first to use spaced booking, having familiarized themselves with the vertical booking of the Iowa, sarcastically remarked that “you have to write off skillfully”.
And most importantly, the thickness of the outer layer, equal to 37 mm, does not give any guarantee of destruction of the tips. According to experts, to fulfill this role, a thickness of at least 50 mm is required, and for guaranteed destruction - about 75 mm. In addition, none of the publications indicate what steel this outer skin is made of. Of course, most likely the steel there is armor, but … the question remains.
And the last thing. If the system of onboard armor protection for battleships of the South Dakota and Iowa types is so effective, why then did the American shipbuilders abandon the internal armor belt in the project of the battleship Montana? In the end, it was not for nothing that American designers of those times, who in no case could be suspected of a sudden "softening of the brain" or of other similar diseases, immediately after the abolition of displacement restrictions (when designing battleships "Montana") abandoned the internal armor belt in favor of the external one.
After all, the booking scheme of the battleship "Montana" in general terms repeats the booking scheme of the battleship "North Carolina". There is another example - the large cruisers of the Alaska class, laid down almost two and a half years later than the South Dakota, also had an outer armor belt. Thus, the merit of the 37mm cocking armor is highly questionable. In addition, it has negative aspects. Any ships of the destroyer class and higher, with any type of ammunition, at any distance, can successfully shoot at vertical armor "Iowa", because the outer layer is only 37 mm. Even in the smallest case, time-consuming repairs are guaranteed (possibly dock). There is no access to the outer armor from the internal premises, even the installation of a plaster is problematic, and there is nothing to say about a better sealing of the hole outside the base. This means that water intake, a roll, an increase in draft, a decrease in speed and maneuverability are ensured in battle. So that is a win-win option, hit her with a land mine - there will be a hefty hole - extensive flooding - a decrease in speed. Hit with armor-piercing - the cap is intact after sheathing - breaking through - hello to boiler houses and machines. At long distances, it is also good - a projectile, hitting the waist armor, can slide down, explode and pierce both the outer side and the anti-torpedo protection, which is not designed for such explosions at all, and this is already serious.
So, on "the best battleships in the world" we have a thin inclined belt (307) and side plating (37). (For comparison: Bismarck - 360 mm, King George V - 374 mm, Rodney - 406 mm, Vittorio Veneto - 350 + 36 - this is a more reasonable scheme, Richelieu - 328 + 18). Moreover, with not the most rational placement.
In front, the armored belt was closed by a high traverse bulkhead, which went from the second (armored) deck to the third bottom; the stern traverse covered only the space between the second and third decks (the armored "box" of the steering gear began below). Armor "class A" was traverse, but its thickness on ships of the series was different. Iowa and New Jersey had nasal plates 287 mm thick at the top and 216 mm thick at the bottom; aft transverse - 287 mm. Such protection can hardly be called satisfactory, especially since during longitudinal fire, a projectile that pierced the traverse can most likely end up in the gun magazines of the first and third turrets of the main caliber with all the ensuing consequences. The horizontal armor of the Iowa (37 mm + 121 mm) is generally at the level of other modern battleships (for comparison: King George V - 31 + 124, Richelieu - 150 + 40, Vittorio Veneto - 36 + 100, the Germans have a different scheme - the deck is thinner (Bismarck - 80), but the projectile must first pierce the upper Bismarck belt - 145 + 30). As you can see, although on the level, only the Italian is worse armored. In addition, as further experiments showed, greater protection is provided by a scheme in which a thicker armored deck is located on top. Those. the defense of the same “Reshelie” is not just better, but much better. I deliberately do not make comparisons between Iowa and Yamato bookings anywhere. In my opinion, it makes no sense to compare these battleships, since the advantage of the Yamato is too obvious.
This is clear even to Americans. That is why they everywhere mention that, they say, Japanese armor was inferior to American and British ones. True, no one has ever conducted research on armor with the Yamato. This is an old and very persistent myth about the quality of armor of different powers, launched into circulation by the Americans and supported by the British. In favor of the fact that this is a myth, in addition to what has been said above, the following can be added.
First: as the best armor of the period of the First World War, in various books by serious authors they call English, Austro-Hungarian, Italian … We can choose any one according to our taste.
Second: Raven and Roberts in British Battleships of World War Two write that "the results of experiments carried out with the new armor plates have not been published and are still UNKNOWN." This is the same English armor that is almost universally called the best in the world. No comments.
Third: the post-war shooting in the United States of a trophy plate made of VH-type armor with a thickness of 660 mm (intended for the unfinished Shinano, but not installed on it; it was conditioned or rejected, it is not known). Only 2 (!) Shots of 16-inch shells were made. According to the test results, the protective effectiveness of Japanese armor was estimated at 0.86 of the American type A. But at the same time and there, the Americans tested another armor plate of the same type VH of a smaller thickness (183 mm), which was recognized as the best plate of all plates. ever tested by the American Navy. And now, based on all of the above, is it possible to assert that Japanese armor is significantly worse than American armor? And can it even be argued that the "best in the world" battleships had the best booking in the world? And do not forget that the American battleships had a displacement, on average, a quarter higher than that of the European ones.
(Further - about speed, seaworthiness and weapons.)
