Recently, a highly specialized discussion on the problems of shipbuilding has flared up on topwar. Accumulated thoughts forced to write an article, because it is already impossible to fit them into the comment format. It will again be about ship's armor, so those who have developed an allergy to this subject may not continue to read.
"Cruiser of the destroyer"
Shipboard armor became one of the main disputed objects. The phenomenon of its disappearance, it would seem, has already been discussed from all sides. But, despite the stormy debate, the key points were not voiced.
One of the main arguments: the articles of the load, reserved for booking, were released and it was not clear what. As a result, modern ships do not have a reservation at all, and there is no sharp increase in the saturation of weapons or equipment close in mass to the missing armor. The error of the entire logic of such an assertion is inherent in the very formulation of the question. The fact is that the armor did not disappear. It did not disappear, because it was not there.
Indeed, what ships carried serious booking during the years of WWII? It was at least "light cruisers", but "light" only in the classification of that era. In reality, these were ships with a full displacement of more than 12000 tons. That is comparable in size to the modern RKR Ave 1164. Smaller ships did not have armor, or the booking was purely symbolic: with the thickness of the 25-50 mm plates.
The modern subclass "missile cruiser" did not appear through the evolution of artillery cruisers, but grew out of a destroyer who had never had a reservation. That is how the first in the world RKR project 58 appeared, which received the serial number of the project from the "miner" series. Reclassified into a cruiser, he was by the will of Khrushchev and the leadership of the Navy, in view of the seriousness of the tasks facing him. Especially since he could not be a “squadron” at all, for it was supposed to act purely cruising alone.
Therefore, the most massive oceanic warships are descendants and the development of destroyers of the WWII period. They never carried any armor, and they never had the corresponding loads. There is no need to talk about frigates - ships of such size and displacement have never been booked. Therefore, the possible experiences of the Stark frigate are not from this opera - there was no armor on a ship of similar size even during the WWII period.
“What did the armor go to?”
Nevertheless, the modern destroyer, although it had grown from a destroyer of WWII, was already almost mature enough in size and displacement to a light cruiser of the period of WWII, but never received any armor. Nor do missile cruisers without a mineric origin — Ticonderoga and Glory — and Peter the Great have only local booking of individual systems. Constructed immediately like cruisers, they could get a reservation. Where did the designers put those displacement stocks, which were assigned to armor?
The answer is the same - they did not go anywhere. Modern RKR was designed from scratch, without regard to the armored ancestors. Therefore, it is impossible to imagine them as a structure in which supposedly a certain weight could be laid under the armor, but which was dullly dragged away to “fitness centers”, half-empty interior rooms, exhaust pipe mines, and so on. All these "excesses" exist by themselves, and they did not appear at the price of giving up the reservation. The converse is also true - if armor is required, it is not necessary to cut down the areas of antenna posts and cabins in order to carve out the weight. Just when equipping with an armor of a modern cruiser, its displacement will increase while maintaining its dimensions. For example, “Arly Burke” from series to series is heavy and has grown from 8 448 tons of full displacement to 9 648 tons, extending the hull by just 1,5 meters. Increase 1200 tons could well be spent on armor.
The version that the weight reserved for armor on WWII cruisers could increase the height of reinforcements of the radar antenna posts does not hold water. The KDP of WWII cruisers were located, as a rule, at the same altitudes, or slightly lower - just a few meters. For example, the KDP of the 68-bis cruiser was located at an altitude of 27 meters from the waterline, and the radar antenna post on the 1164 cruiser was located at an altitude of 32 meters. It is hard to believe that 2 910 tons of armor of the cruiser 68-bis went on to raise 5 radar meters on a similar-sized cruiser "Slava". Another example - the battle cruiser Alaska has a KDP at an altitude of 30 meters, and a radar station on 37 meters. The 1144 cruiser of similar size has a radar at the height of the 42 meter. Not observed a sharp increase in the height of antenna posts in other cases.
Perhaps, superstructures began to weigh more? Is it really on 2900 tons? Let's try to imagine the dimensions of the superstructure weighing 2900 tons, made of steel with a thickness of 8 mm. Having made simple calculations, we will find out that it will weigh so much a five-story house with a length of 95 meters and a width of 20 meters. Are such structures visible on the deck of the RKR Ave 1164? Not. Even the “dwelling house” of the Ticonderoga cruiser is three times less.
And nevertheless on what could the weight of armor of light cruisers of WWW on rocket cruisers of similar in size go? No matter what. There is simply no reservation, that's all. If desired, it can be delivered to existing cruisers without any problems and overloads. Modern cruisers just became lighter with the same dimensions.
This is easily seen in the 1164 cruiser. He just has a perfect counterpart in the face of the cruiser "Cleveland". The length is the same - 186 meters, the width of the 1164 - 20,8 m, the "Cleveland" - 20,2 m. Draft 6,28 and 7,5 meters, respectively. But the total displacement of 1164 is 11280 tons, and the Cleveland 14131 ton. With the same dimensions, "Cleveland" weighs 25% more! But in light cruisers armor weight just fluctuated within 20-30% of the standard displacement. What will happen if “Glory” is loaded with armor to the Cleveland’s 14131 ton? That's right, "Glory" will acquire armor, very similar to that of "Cleveland." For example: an armored belt with a height of 6 meters, a length of 130 meters and a thickness of 127 mm, as well as solid armored formwork within the same 130 meters with a thickness of 51 mm. And it will weigh just 2797 tons, i.e. the difference in total displacement between the "Cleveland" and "Glory." Will “Glory”, having received an additional load in 2797 tons, go to sea? Of course he can, because “Cleveland” somehow did it.
The same analogy can be drawn with the 1144 cruiser, which has an analogue in the form of the Alaska battle cruiser. The length of the hulls is 250,1 and 246,4, the width is 28,5 and 27,8, the draft is 7,8 and 9,7 meters. The sizes are very close. The total displacement of the 1144 Ave. - 25 860 tons, "Alaska" - 34 253 tons. Alaska has 4 720 tons of armor. With such a booking weight, 1144 can get an armor belt with a length of 150 meters, a height of 6 meters and a thickness of 150 mm, as well as an armored deck with a thickness of 70 mm. Of course, weaker than Alaska, but also looks solid. At the same time, it is quite obvious that “Peter the Great”, having accepted ballast (or armor) in 4720 tons, will not go to the bottom at all, but will only slightly settle with the hull, and will calmly plow the ocean. The huge difference in displacement between the ships of almost identical dimensions clearly shows that the much more developed and high superstructures of the 1144 project actually weigh just a little, and whether they are twice as bulky and taller - Peter the Great did not weigh heavier than armored Alaska ".
And here is an example of an analogue not in size, but in displacement. Our BOD 1134B is one-on-one similar in displacement to the Japanese light cruisers Agano. At the same time, “Agano” is noticeably already our BOD (15,2 meter versus 18,5) with almost the same length and draft. Here, the reader will say! The ships are the same, and the armor on the BNC 1134B is not! Where did talentless designers get armor-free tons on our BOD? No need to rush to conclusions, you first need to enjoy information about booking "Agano". It had the thickness of the side armor of the whole 50 mm, the deck in 20 and the tower 25 mm. In principle, almost the same today armored carriers of the ground forces. In short, the displacement and size of unarmored rocket ships and their armored artillery ancestors begin to converge when the booking of the latter tends to zero.
"Specific density of the ship"
To verify the above arguments, you can use the simplest, even primitive, but clear way to estimate the density of a ship’s layout. The underwater part of any vessel has a complex shape, and in order not to engage in the calculation of integrals, we simply take the volume bounded by the length, width and draft of the hull. This is a very rough method, but oddly enough, with respect to a multitude of ships gives a pronounced regularity.
Artillery armored ships have a density at full displacement within 0,5 - 0,61 tons / м3. Modern rocket ships to such indicators do not reach. The characteristic numbers for them are: 0,4 — 0,47 tons / m3.
For the pairs of cruisers mentioned by me, these values will be: “Glory” - 0,46 tons / m3, “Cleveland” - 0,5 tons / m3. "Peter the Great" - 0,47 tons / m3, "Alaska" - 0,52 tons / m3. "Nikolaev" - 0,46 tons / m3, "Agano" - 0,58 tons / m3.
There are exceptions confirming the rule. There are armored ships, the conditional density of which is close to that of rocket ships. True, the very booking of such ships can be considered tending to zero. This is a project 26-bis cruiser - 0,46 tons / m3 (like 1164). At the same time, the thickness of armor of 26-bis cruisers does not exceed 70 mm and it is difficult to consider them as “seriously” armored ships.
The second example is the battleships of the “Deutschland” type, Germany’s famous diesel raiders - 0,42 tons / m3. But their booking does not reach even that of the “light” Cleveland: 80 mm board and 45 mm deck.
It is clear that the armored ships are heavier. Nevertheless, this did not prevent them from plying the oceans as well as modern rocket descendants. From modern rocket ships, the armor was simply removed, without in any way using the released constructive stocks of the masses. Therefore, rocket ships have simply become lighter, and nothing more.
"If not armor, then why not weapon?»
Of course, the statement that a modern missile cruiser can freely hang armor, equal in weight and thickness to the respective ships of WWII, is a simplification. But it clearly shows that modern ships are in fact underused and, if desired, they can be booked to one degree or another. And without radically changing the composition of the weapons, the ammunition, and without reducing the payload as a whole.
There is one more question. If modern ships are so underloaded and have impressive reserves for the masses, why not put on them at times more weapons? If not for armor, then at least you can spend this supply on a weapon!
And here already other laws come into force. Armor is compact, because steel has a density of 7800 kg / m3. Missiles, computers, radars and other things with such a density is not. It means that volumes and areas are required. And this is an increase in size, followed by displacement.
The proposal described above for the possible equipping of the Slava cruiser has a lot of “unused load” in 2 797 tons. This weight easily fits more than 12 sets of the “Fort” air defense missile system, as part of 12 radar of illumination-guidance and 768 of missiles in drum starters. That is, the stock in weight is huge, but can someone, looking at the RKR drawings of 1164 Ave. find the free space or volume to accommodate additional TPC missiles of the “Fort” complex? No, those are not found. Increase ammunition does not work, and not because of congestion, but because of the lack of free spaces. Even if the habitability is reduced to the level of “everyone is sleeping along in one common barracks”, to cut off the masts and superstructures, there will not be room for such a number of missiles. And this situation will be on any modern ship, be it Ticonderoga, Glory, or Peter the Great.
Finally, no one argues that modern ships are ideal, maybe soon there will be a ship with a better layout, more saturated with weapons.
“Why is there no armor?”
If it is possible to put armor, why does nobody put it on? Everyone knows why armor disappeared from ships in the era of nuclear weapons, but that’s why it has not yet appeared again is not entirely clear.
And the answer lies in the armor penetration of modern warheads of anti-ship missiles. The presence of an armor belt with a thickness of 150-200 mm does not fundamentally solve the task of protecting the ship. It only reduces the likelihood of damage from warheads with low armor-piercing (X-35 missiles, Garpun, Tomahawk, Exocet), but it doesn’t save “big” missiles from the warhead. The armor penetration data is still not advertised, but there is one exception. It is known that the cumulative high-explosive warhead BCR PKR "Basalt", which is in service with the cruisers of the project 1164, breaks through the 400 mm of armored steel. It seems that the numbers for Granite are not particularly smaller, but rather, even more. It is possible that the armor penetration of Bramos non-cumulative warheads or Mosquito missiles is smaller, but not many times.
Under these conditions, the presence of 200-300 mm thick, but negligibly small in terms of area, armor does not play any role. If even a rocket hits him, she punches him without any problems. Even for light RCCs that do not have high kinetic energy (low flight speed and mass of the warhead), a compact cumulative warhead can be built that can cope with at least an 100-mm barrier. A thicker armor on ships dimensions of the modern destroyer will not appear. The Super Cruisers like Peter the Great may not be stoked by the Harpoons or the X-35, but by the Granit and the Basalt. Even if the target is a battleship from the time of WWII, for example, “Iowa” - its armor in 330 mm is not a problem.
It turns out that those who want to build modern battleships propose to create target ships for an already existing means of destruction. That is why the armor is not being revived in full even nowadays. Shoot down missiles on approach in any case more effective. Active protection prevents problems, passive - only allows to reduce their consequences with a certain luck.
In this case, the presence of splinterproof booking on modern ships no one disputes. Armor on rocket ships should appear, and its area and weight will only grow with time. But the purpose and role of such a booking is completely different than that of the WWII cruisers. Prevent any penetration of armor from the warhead of the PCR PKR today is capable of, but to reduce the effects of this penetration completely. Do not approach such armor to the parameters of the time of WWII and by weight.