Myths of the United States. Battleships "Iowa". Part one
Many English-speaking, and after them, and domestic experts called the Iowa type 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, speed and weapons. Let's try to figure out whether this is so.
On the booking system of battleships like "Iowa" a lot of all kinds of fiction have been written. That, in general, is not surprising: the ships were designed after the start of the Second World War, and the Americans did not seek to disclose their true characteristics. And the information that leaked to the press, often was a clear misinformation. And 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 that they were afraid!”). Therefore, in many respectable reference books and monographs, the absolutely fantastic thickness of the armor belt “Iowa” in 457 mm has long been “walking” - one and a half times more than in reality. According to declassified data after 60 years, the Iowa’s armor protection was almost exactly the same as that used on its predecessors, the South Dakota type of battleships. The main armor belt with a thickness of 307 mm (!) Was located inside the hull between the second and third decks and had an inclination of 19 ° outwards.
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 a projectile flying horizontally, the inclined armor belt was equivalent to the vertical thickness 343 mm. At high angles of incidence of shells, the effectiveness of the Iowa belt armor increased sharply, but the probability of hitting the belt became low. Inclined armor belt increases armor resistance in proportion to the reduction in protection area. The greater the deviation of the projectile's trajectory from the normal, the greater the protection the oblique armor belt gives, but the smaller the area (!) This armor belt covers.
But this is not the only drawback of oblique armor. The fact is that already at a distance in 100 cab. the projectile deviation from the normal (i.e., the projectile angle relative to the water surface) of the WWII battleships GH guns ranges from 12 to 17,8 hail (Kofman has a remarkable sign in the book of Japanese Yamato battleships, Musashi) on page 124). At a distance in 150 cable, these angles increase to 23,5-34,9 degrees. Add to this another 19 hail of tilting of the armored belt (South Dakota) - we get 31-36,8 hail on 100 cable and 42,5-53,9 hail on 150 cable. It turns out that the oblique armor belt, located at an angle of 19 hail, practically guaranteed that the projectile would crack or ricochet at a distance in the 100 cable (18,5 km). If it suddenly cracks - well, but if there is a rebound? The fuse may well be arrested from a strong sliding blow. Then the projectile will “slide” along the armor belt and go through the PTZ straight down, where it will jerk fully under the bottom of the ship.
A lot of publications that say that the internal location of armor on the "Iowa" served to destroy ("remove") the armor-piercing ("Makarovsky") tip of the projectile, which increases the armor resistance. However, in the well-known design documents of the “South Dakota” and “Iowa” types, there is nothing to say that the designers deliberately used a spaced booking scheme and took into account the destruction of the armor-piercing tip of the enemy shell by the outer skin of the board.
The design of the battleship type "Iowa" was carried out in the absence of contractual restrictions, however, the head of the General Council fleet US Admiral Thomas Hart, for domestic political reasons, ordered the designers of the new ship to try not to overestimate the displacement, which, given the very high requirements for armament and speed, clearly meant saving on booking. So the American shipbuilders simply repeated the existing technical solution and reproduced the South Dakota reservation scheme with minor modifications on Iowa. And the same S.A. Balakin in the monograph “battleships of the type“ Iowa ”does not at all note the special role of the outer skin of the side.
It turns out that the internal arrangement of the onboard armor belt was used on these two types of ships for reasons of reducing the weight of the armor and, as a result, the displacement, and there was no talk of "removing armor-piercing caps" of projectiles. By the way, the Italians, the first to apply the spaced booking, having familiarized themselves with the vertical booking of “Iowa”, sarcastically noticed that “you must 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, a minimum thickness of 50 mm is required to fulfill this role, and for guaranteed destruction it is of the order of 75 mm. In addition, no publication indicates what steel this outer skin is made of. Of course, the steel is most likely armored there, but ... the question remains.
And the last. If the system of on-board armor protection of battleships of the “South Dakota” and “Iowa” types is so effective, why then did the American shipbuilders in the design of the battleship “Montana” abandon the internal armor belt? In the end, it’s not for nothing that American designers of those times, who in no case can be suspected of either a sudden “softening of the brain” or other similar diseases, immediately after lifting the restrictions on displacement (when designing the “Montana” battleships), refused internal armor in favor of external.
After all, the booking scheme of the battleship Montana in general repeats the scheme of booking the battleship North Carolina. There is one more example - the big cruisers of the “Alaska” type, laid down almost two and a half years later than the “South Dakota”, also had an outer armor belt. Thus, the dignity of the 37-mm cocking armor is extremely doubtful. In addition, it has negative sides. Vertical armor "Iow" can successfully shoot any class ships from the destroyer and above, any type of ammunition, at any distances, because the outer layer of the entire 37 mm. Even in the most minimal case, time-consuming repairs are guaranteed (perhaps, dock). From the interior there is no access to external armor, even the establishment of a plaster is problematic, and there is nothing to say about a better seal of the holes outside the base. This means that in battle, water intake, roll, increased precipitation, reduced speed and maneuverability are provided. So the safe option, hit it with a bomb, there will be a hefty hole - extensive flooding - a reduction in speed. Beat armor-piercing - the cap after plating is intact - breaking through - hello to boiler houses and cars. At long distances, it is also good - a projectile, hitting the belt armor, can slide down, break and pierce both the outer side and the anti-torpedo protection, which is not designed for such explosions at all, and this is serious.
So, on the “best battleships in the world” we have a thin inclined belt (307) and bead lining (37). (For comparison: "Bismarck" - 360 mm, "King George V" - 374 mm, "Rodney" - 406 mm, "Vittorio Veneto" - 350 + 36 is a more reasonable scheme, "Richelieu" - 328 + 18). And with its not the most rational placement.
The front armor belt closed high traverse bulkhead, which went from the second (armored) deck to the third bottom; aft traverses covered only the space between the second and third decks (below began the armored "box" of the steering gear). On the traverse went armor "class A", but its thickness on the ships of the series was different. In Iowa and New Jersey, the nose plates were 287 mm thick at the top and 216 mm at the bottom; feed cross - 287 mm. Such protection can also hardly be called satisfactory, especially since with a longitudinal fire the projectile which pierced the beam could most likely end up in the cellars of the first and third towers of the main caliber with all the ensuing consequences. Horizontal armor "Iow" (37 mm + 121 mm) in general at the level of other modern battleships (for comparison: "King George V" - 31 + 124, "Richelieu" - 150 + 40, "Vittorio Veneto" - 36 + 100, the Germans have another scheme - the deck is thinner (Bismarck - 80), but the projectile needs to break through the upper belt of the Bismarck - 145 + 30). As you can see, even at the level, only the Italian is worse booked. In addition, as shown by further experiments, greater protection is provided by the scheme, in which a thicker armored deck is located on top. Those. protection of the same "Reshele" is not just better, but much better. I deliberately nowhere compare comparisons of the Iowa and Yamato bookings. In my opinion, it does not make sense to compare these battleships, since the advantage of Yamato is too obvious.
This is clear even to the Americans. That is why they are alluded to the fact that, say, Japanese armor was inferior to American and British. True, no one has ever conducted research on armor with Yamato. This is an old and very persistent myth about the quality of armor of various powers, launched by the Americans and supported by the British. In favor of the fact that this myth, in addition to the above, you can add the following.
First, as the best armor of the First World War in various books, serious authors call English, Austro-Hungarian, Italian ... We can choose any one to your taste.
Second: Ravens and Roberts in the "British Battleships of World War Two" write that "the results of the experiments conducted with the new armor plates have not been published and so far UNKNOWN." This is the very English armor, which is almost universally called the best in the world. No comments.
Third: the post-war shooting in the USA of a trophy plate of armor of type VH, 660 mm thick (intended for unfinished Shinano, but not installed on it; it was conditional or rejected, this is not known). Made all 2 (!) Shot 16-dm shells. According to the test results, the protective effectiveness of Japanese armor was estimated at 0,86 from the American type A. But then, and there, the Americans tested another plate of armor of the same type VH of smaller thickness (183 mm), which was recognized as the best plate of all the plates either tested by the US Navy. And now, on the basis of the foregoing, can it be argued that Japanese armor is significantly worse than American? And is it even possible to say 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 of, on average, a quarter higher than that of the European.
(Further - about speed, seaworthiness and armament.)
Sources:
http://wunderwafe.ru/Magazine/MK/2003_N1/
http://modelizmspb.temza.ru/temas/rkka/statia/23vs.html
http://korabley.net/news/linkori_tipa_aiova_vsem_linkoram_linkori/2008-11-22-62
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