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BattleshipOfDestruction

Designing Warships: A Historically Driven Practical Guide

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Hi, I am BattleshipofDestruction and welcome to this guide on historical ship design. I have been fascinated with Naval Technology since my grandfather told me the stories from his WWII service in the US Navy. This will be a general guide and thus will not be specific to any particular era of ship design. It is simply a primer to introduce you to how ships were historically designed and also pros and cons of each design decision so you can make more informed decisions with your own fleets when the campaign releases. This information comes from years of obsessive research into the subject and lots of reading on the subject which may have some inconsistencies. This may not represent how the mechanics are in the actual game yet or by release.

First off, let us talk about the general characteristics of the existing ship classes available to design in the current version of Ultimate Admiral Dreadnoughts. This will cycle from the smallest ship to the largest of them all.

The Torpedo Boat:

Beginning with the humble torpedo boat we see it is a very small maneuverable craft with no armor to speak of. In early technology this little boat can knife through the water faster than a destroyer while still delivering a fairly devastating payload of torpedoes to even the largest ships. The general design schematics of torpedo boats is that they are armed primarily with torpedoes and their auxiliary weapons are guns of a caliber of 5 inch or less. These auxiliary armaments are sparse, usually only a few turrets, because the main job of a torpedo boat is to deliver large spreads of torpedoes to the target while under fire. Early technology will let you access single center-line torpedoes, but later technology will allow you to mount more intimidating numbers of torpedoes. The main advantage of such a craft is its speed and maneuverability to stay out of trouble and its strong torpedo armament and also they can be made very cheaply in a relative sense. The disadvantage is being that they are not armored and have minimal bulkheads, any larger ship that has accurate cannons should be able to send a torpedo boat to the bottom in only one or two hits due to the over-penetration and flooding that occurs because of it. The modern torpedo boat is often armed with depth charges for anti-submarine duty.

The Destroyer:

The Destroyer is a very effective tool to attack larger surface ships and raid convoys. They were also used historically for anti-submarine warfare (commonly abbreviated ASW). They are more armored than a torpedo boat and are also a direct descendant from the previous ship class. They are typically armed with large numbers of 5 inch guns in up to dual mounts. They are slightly less maneuverable and fast than a torpedo boat, but they still inherit a strong torpedo armament from the torpedo boat, both as a center-line design and like cruisers, sometimes port and starboard mounted. Destroyers have much more bulkheads than the Torpedo boat, due to its larger size and added armor, however a destroyer's armor is inadequate against even some light cruisers sporting 6 inch guns. Like the torpedo boat, a destroyer's speed and maneuverability, in addition to being able to smokescreen a battleship or larger fleet unit makes it a very versatile ship class, built to adapt to most situations. Although a support craft by designation, it can do combat against light cruisers and larger units as long as a tactical maneuver is used called "chasing splashes". This classic defensive tactic is used to follow the columns of water from impacting enemy shells; gambling that the enemy gunners do not shoot in the same place twice and instead adjust their rangefinders which impedes their accuracy. Such a tactic was used to great effect in the WWII Battle Off Samar by Destroyer USS Johnston. Never underestimate the destroyer as it can surprise you and your fleet as it can the enemy with your own destroyers. Common designs include the Fletcher and Allen M. Summer Class by the US Navy and the Fubuki Class of the IJN.

The Protected Cruiser:

This version of the cruiser is before the designations of cruisers varied between "light" and "heavy" cruisers which were popularized by the Washington naval treaty set forth after World War I. They were typically medium to heavily armored for their time and could hunt destroyers and rain down high explosive fire on larger fleet units to cause fires. Most protected cruisers had a main armament of 5 inch guns or 6 inch guns primarily in casemates, but sometimes located in dual mounted turrets (one bow, one stern) on the ship. This cruiser typically wasn't fast enough to catch a destroyer, however it could effectively deal with destroyers in self-defense and provide fire support against larger surface targets. Although their speed by mid 20th century standards were quite poor (most achieved only 20 knots) they did have high broadside capability for those smaller guns and were decently well armored despite their size.

The Modern Light Cruiser:

The Light Cruiser was borne out of the idea of a faster cruiser with 5-6 inch guns that would be able to effectively hunt down destroyers while still having high amounts of fire support available during large fleet engagements and also shore bombardment. Their main armament is mainly found in dual or triple mounted turrets, though single turrets were common in the early years. Some were built with armor that could stop destroyer caliber weaponry, other than the torpedo, while others could still combat against heavier cruisers with their armor being thicker than the other common light cruiser role. Some cruisers, both light and heavy were armed with "wing" mounted torpedoes. These were useful for impeding an enemy advance and in single combat against a superior enemy fleet unit such as a battlecruiser or battleship of any kind. Most Japanese cruisers were fitted with torpedoes, while US cruisers tended to favor all-gun concepts for fire support and destroyer hunting roles. They have decent speed and maneuverability, some even matching destroyers, and they do have increased armor, though not often as protected as a heavy cruiser. They do have a normal amount of bulkheads to prevent flooding from being a bigger threat, though they still succumb to torpedoes just as much as destroyers do as they lack torpedo protection. Light cruisers are also purpose built commerce raiders so they can in-essence, be very well suited to destroying armed convoys of supplies that are only protected by destroyers. During WWII, most light cruisers in US service used Dual purpose main batteries to fire Anti-Aircraft shells to combat enemy pilots. As such light cruisers are also historically useful for such a role when purpose built for it. Examples of this class include the Atlanta and Cleveland class of the US Navy and the Mogami Washington Treaty "Light Cruiser" of the IJN.

The Modern Heavy Cruiser:

The heavy cruiser was born out of the necessity to diversify the design of a cruiser after the protected cruiser design became obsolete. They are usually armed with 8 inch guns in dual or triple turrets, though single turrets were indeed common in the early years. These are the most likely cruisers to be able to combat larger fleet units effectively while still being a light cruiser killer of sorts. They are typically slightly slower and less maneuverable than a typical light cruiser, but that trade-off is in favor of increased armor to defend against other 8 inch armed warships. The 8 inch HE shells were particularly nasty to the superstructures of enemy battlecruisers and battleships, and also their less protected deck on the bow. These cruisers are able to set fires more easily due to the increase in caliber. They also frequently come armed with torpedoes, but that design decision is not set in stone, unlike a destroyer which survives on lots of small guns and torpedoes. Again the US and Japanese viewpoints on a Heavy cruiser's role differs from that of an all gun fire supporter or a balanced large fleet unit. They also typically had more secondary batteries of 5 inch caliber compared to light cruisers. Armor is still an issue against battlecruisers and battleships, but although it can be a problem against heavy cruisers with the same armor layout, it is otherwise unsinkable against other smaller fleet units unless it is hit by a torpedo. Examples of this class include the Tone-Class of the Imperial Japanese Navy and the Pensicola Class of the US Navy.

The Battlecruiser:

The Battlecruiser is kind of a stepchild of a heavy cruiser and a battleship. It is a heavy cruiser killer that has the same speed and maneuverability as a heavy cruiser and slightly higher armor to combat those units, while having the big guns typically found on full battleships. This means that the caliber of the big guns can vary greatly from ship to ship and era to era. The most general range for this class is from 11 inch guns if you count the Deutchesland Class of Battleships as part of that group (commonly referred by British news of the time as Pocket Battleships) to the 15 inch guns of HMS Hood. Other notable examples include the 14 inch armed Kongou-class battlecruiser of the IJN. This design comes with the firepower advantage of a battleship and mostly a secondary suite to match along with comparable speed and maneuverability to a heavy cruiser, but lacks armor to combat larger battleships especially due to the danger of plunging fire at longer ranges.

The Pre-Dreadnought:

This is the earliest type of battleship and was popular in the 1890s and early 1900s. The engagement distance at the time was rather short due to the inaccuracy of the guns of that period and the lack of sophisticated aiming systems technology. The armor was relatively high enough to deflect rounds of the same general largest caliber that the ship had mounted and because it was a flat trajectory, armor schemes became more focused on protecting the hull instead of the deck as plunging fire was less common. Sporting two to three turrets in dual mounts of 11-13 inch, they were the mainstay of early-modern military fleets. Although armor quality varied between the nations, the thickness of the armor wasn't enough to cause some ships to sink. Just because of the lack of armor quality in some nations, their ships were easier to sink compared to those who were more advanced in steel production.  Thus, this battleship-type spurred an arms race began between the nations to find a better way to build battleships. These ships also had ridiculous amounts of casemate mounted secondary armaments of various calibers which was not surprising compared to the relative engagement distance. Also, because not many battleships of that era had torpedo protection, most were mounted with underwater launchers on the broadsides to compensate for not having the guns to penetrate each other. Against any dreadnought or higher, it doesn't stand a chance unless retrofitted with more armor and better weapons. Pre-dreadnoughts are also slow warships, most not exceeding 20 knots, so they cannot hope to compete with more modern ships. Battleships are generally cost prohibitive to smaller navies which is why you need lots of money and raw materials to produce one well-equipped to go toe to toe with another navy's battleship.

The Dreadnought/Super Dreadnought:

So named after the original semi-dreadnought named HMS Dreadnought, it was also what made the battleship arms race heat up for other nations. Although this achievement was groundbreaking, it did strain military budgets for other nations including the British and lead to the eventual signing of the Washington naval treaty. This was the beginning of the All-Big-Gun concept of battleships that continued into the mid 20th century. The concept was for a battleship to have as many of the same caliber of main armament as possible. This translates to two center-line turrets and up to 4 side mounted turrets of dual mounted 12-14 inch guns. The term-semi-dreadnought was for the early version of a standard dreadnought which had less armor than it's predecessor in exchange for more turrets of it's main armament. The amount of casemates on these ships were reduced to make way for more big guns to be placed on deck. This also allowed for turreted secondaries which came later on in the development of battleships. In the meantime, the ships had minimal secondaries, but instead were bristling with big guns from bow to stern. Later dreadnoughts had center-line mounted turrets and even superfiring ones to increase the effectiveness of the main battery. Some dreadnoughts of Russian design even did away with the superfiring concept to allow for 360 degree turning center-line turrets to increase the number that can fire when angling toward and away from an enemy. The Japanese navy had a large number of dreadnoughts at their disposal at the beginning of World War II and frequently used them in combat to varying effect. The later dreadnoughts are somewhat on par with modern battleships, but even when modernized can be less effective at what they were designed for due to inferior guns and armor. Also their "Turtleback" Armor Scheme, which was popular for late-era dreadnoughts, were vulnerable to engagements at long distances. The super dreadnought is like a dreanought, but were a more stable platform to receive much needed upgrades in caliber (up to 16 inch) and armor against these guns. Examples of the Super dreanoughts were the Battleships of the Standard-Type Program of the US Navy which comprised the Nevada Class, Pennsylvania Class, New Mexico Class, Tennessee Class, and Colorado Class and also the Nagato Class of the IJN. By the time the Super dreadnought came along, the US had pioneered a new more cost effective battleship armor scheme called "all-or-nothing." This type of scheme only protected the most vital parts of the ship in order to not only reduce weight, but increase the amount of armor available to the parts that needed it while reducing armor in non-essential areas. This new scheme became the most effective armor in battleship design for all ranges as it solves the plunging fire problem prevalent with the Turtleback armor scheme. The early semi-dreadnoughts and mid-era dreadnoughts tend to be very slow, most not breaking 22 knots and thus are not effective in a chase with other ships. The cost of these warships was relatively high because of the technology and armor involved, but still command a worthy upgrade to the pre-dreadnoughts. Late-era dreadnoughts and super dreadnoughts featured the first experimentation with torpedo bulges which continued to evolve with the inclusion of multi-bottomed hulls throughout the rest of the age of the battleship. They also sometimes had speed increases that make them also designated Fast Battleships.

The Fast/Modern Battleship:

This design is essentially a cross between a super dreadnought and a battlecruiser. While partially inheriting a higher speed from the battlecruiser, it still has equal or greater armor and also much higher caliber weaponry than a super dreadnought battleship. They typically are armed with 14-16 inch guns and have slightly less armor than their super dreadnought cousins, but must have armor that can still hold its own against other battleships. This made the design of these ships very difficult to balance firepower, protection and speed while maximizing the capacity for combat with other battleships. Examples of this class are the Iowa-class from the US Navy and Both the Kongou and Nagato Classes (post 1930s refit) of the IJN. Although some of these classes are super dreadnought or battlecruiser in design, their speed is comparatively more than late-era dreadnoughts. The speed was usually ranging from 26-33 knots. The All-Or-Nothing Armor Scheme became standard for most navies implementing modern battleships, however Germany and Japan did evolve the Turtleback armor scheme to include angled underdeck armor that would help deflect any debris from an incoming shell to protect from plunging fire which made them more survivable than existing super dreadnought designs. This design included a plethora of 5 inch secondaries, where the US Iowa Class had the most of these caliber on board. Overall this design is the best battleship design to go for if you are looking for a well balanced battleship navy. These are possibly one of the most cost effective battleships if you choose an all or nothing scheme with a cost effective armor quality.

The Super-Battleship:

The term Super-battleship was for a warship based on a modern battleship design, which was supersized to even impracticality. They were typically armed or designed with 16-18 inch guns, but some that were never built came with plans for 20 inch guns, specifically the later H-Class proposals for Germany's Plan Z and the Super Yamato which was essentially a Yamato with 20 inch dual mount turrets. Although the Bismarck class was sometimes referred to a super battleship due to its reputation for being very well protected, its fully loaded displacement of 50,300 long tons doesn't make any sense to use the designation compared to the likes of Yamato and the Planned H-Class of Germany's Plan Z. The Yamato was the only Superbattleship built, but other classes that were proposed suggest that this class started at 72,000 long tons fully loaded to exceed well over 120,000 long tons. They also had the deck space for a lot of secondary batteries of 6 or 8 inch caliber and also multiple 5 inch guns with other assorted small arms. The speed of these mammoth ships varied from 20 knots to well over 30 knots for blueprint designs. They also had the best versions of their respective armor schemes in the world. Whereas the Yamato had an enhanced Turtleback armor Scheme to protect against plunging fire, the Montana Class of US design which had an extra 3 gun turret of 16 inch guns and higher protection in an all-or-nothing scheme made it the Yamato's hypothetical equal. The only reason to consider building a battleship of this size is if you wish to have a more qualitative navy because you do not have the industrial capacity to build higher numbers. While on paper, these ships can out-range potentially every ship in other navies and out class their armor, they are still lumbering beasts with very cumbersome maneuverability compared. In addition, the rate of fire of these large caliber naval rifles are so low that even 16 inch guns on lesser ships could outpace them in a gunfight assuming rangefinders and accuracy are equal. In addition, such ships are very costly and take a much longer time to build than smaller battleships. Finally, they are still not invulnerable to torpedoes, although they can take much more of a beating and may be able to survive multiple torpedo hits unscathed due to enhanced damage control, better torpedo bulges, higher number of bulkheads with higher tolerances and multi-bottomed hulls.

 

Now that you have learned about the general ship types and their roles, we can focus on a few design decisions that assist in the process.

Design Decisions:

General:

Number of Bulkheads: The greater number of bulkheads in the ship, the better a ship can be sealed off from out of control fires and preventing flooding of the rest of the ship.

Reinforcement of Bulkheads: The greater the reinforcement of the bulkheads, the greater chance your ship will not founder against enemy shells (due to spaced armor) and the resistance in water pressure they can take from flooding.

Armor Composition: The higher quality the armor plating, the lighter the armor is; allowing for more of it and increasing the overall strength, allowing for less armor to block the same caliber shell as more armor of an inferior quality.

Anti-Flood: The higher the value, the faster it is to recover from flooding and to pump out water from affected sections.

Torpedo Bulge:  The higher the value, the better protected your belt armor is from torpedo attack.

Number of Hull Bottoms: The higher number of bottoms to the hull, the more resistance the ship has to torpedoes and flooding caused by shell damage.

Citadel Armor Scheme: Usually the higher, the better. Go for all or nothing as soon as it is unlocked. It provides the best protection for a warship.

Superfiring Turrets: On cruisers onward, when technology is available, you will have the option to mount super firing arrangement of turrets. This allows the turrets to be on different elevations and thus increase the angles at which you can get more turrets to fire. This design decision is at the cost of a less stable ship in the long run.

Side mounts and casemate guns: These are best used on older dreadnought battleships which allow more big guns and casemate mounted secondary guns to be aboard ship. The cost is limited angles of fire for those side mounts and casemates. Note that center firing ships along with sometimes super firing placement is a much better way to get more guns on target.

Main Gun Turret Placement Schemes:

Practical Turret Configuration Legend:

A-D: Forward Turrets

L-O: Amidships Turrets

W-Z: Aft Turrets

- : Funnel, Tower or Obstacle

Balanced Gun Scheme(A-X, AB-XY or ABC-XYZ): These ships have an equal number of primary turrets on the forward and afterward end of the ship. This has the advantage of being on par with a standard comparable enemy compliment of primary weapons bringing their armament to bear as they are advancing, chasing or retreating. The disadvantage is that unless you expose at least a bit of your broadside, which is safer for angling or go completely broadside on to your enemy (where your armor is at its weakest point) you can end up limiting the amount of turrets able to fire at them by up to half. To make sure you only expose a small broadside and thus retaining an advantage to angling your armor, make sure all primary turrets have the best firing angles that you can design into it. This design decision is best for any Modern Battleship and Pre-Dreadnoughts. It is also ideal for Battlecruisers and Non-aggressive Cruisers. Time for aiming for the turrets on the opposite end of the ship takes slightly more time than Centerline mounted 360 degree Turrets.

All Forward Gun Scheme(ABC or ABCD): These ships are best used when advancing at an angle as it can get its super firing guns on target and not have to turn broadside on which lowers the effective thickness of the armor. Effectiveness is reduced when kiting away from the enemy as not all primary guns can get on target. It is a better idea than the afterward scheme only if at least one gun can fire back when retreating. To maximize efficiency and survivability of this design, place the primary armament in such a way that the turrets have the best firing angles. It is Best for Pure Aggressive Modern Battleship with good enough armor. This configuration is also okay for aggressive Battlecruisers, but not recommended. It presents a severe handicap to Firepower when retreating directly away.

All Afterward Gun Scheme(XYZ or WXYZ): These ships are best used when retreating at an angle as it can get its super firing guns on target and not have to turn broadside on which lowers the effective thickness of the armor. Effectiveness is reduced when advancing toward the enemy as not all primary guns can get on target. It is the worst battleship gun arrangement idea and defeats the purpose of such ships to have such a thing as a “fire when retreating battleship.” No historical Battleship design or any capital ship has this arrangement.

Majority Forward Gun Scheme(ABC-XY or AB-X): These ships have most of their primary armament towards the bow, allowing for fights advancing towards the enemy with greater firepower advantage than comparable balanced turret layouts, though when turning away it can turn away with only the standard amount of turrets able to fire back. To maximize efficiency and survivability of this design, place the primary armament in such a way that the turrets have the best firing angles. It is an okay Configuration for BBs if wanting to be aggressive, while still being able to fire back while retreating directly away. It is better than All Forward scheme for retreating BBs who angle while retreating to get more than average guns to bear. Configuration is also ideal for maneuverable Battlecruisers and Aggressive Cruisers.

Majority Afterward Obstructed Gun Scheme(AB-XY-Z, or AB-WX-YZ): These are used mostly on older ships of a Japanese or British variety and contain the majority of superfiring guns placed amidships or further aft with a secondary tower in between a superfiring pair on the stern. This design has the advantage of being able to fire a large broadside while kiting away, but comes with the disadvantage that you have to expose a lot of broadside to get all the guns firing and when you are advancing you could be at a slight disadvantage. To maximize efficiency and survivability of this design, place the primary armament in such a way that the turrets have the best firing angles.  It is the second best  configuration for Dreadnoughts and Super Dreadnoughts. Though, it is not recommended for Modern Battleships, Battlecruisers or Cruisers.

Broken Non-Super firing Centerline Gun Scheme(A-L-O-X, A-L-M-O-X or A-L-M-N-O-X): This gun scheme is used by the Russian Empire and the Soviet Union in their early to mid 1940s battleship designs. It consists of at least four primary turrets being put in a centerline row between towers, funnels or other obstacles and at least one turret at the bow and the stern. The guns are arranged in such a way that nearly all of the guns have 360 degrees of rotation and/or the highest angles of fire possible. The turrets can sometimes be grouped in two turret centerline arrangements between obstacles, but it is a rarity for this design. This design also implements the mandatory use of triple turrets, allowing more firepower in a smaller package. This design has caveats in the form of needing to expose some broadside for the most afterward gun house to fire which can cause partial penetrations on the deck and that advancing straight on has the least effectiveness of the ship in a chase using this configuration. This configuration is best for Dreadnoughts and Super Dreadnoughts. It is not recommended for Battlecruisers or Cruisers. The configuration could do well on a modern Battleship if you make sure all turrets can rotate 360 degrees for maximum field of fire. A good modification is to implement super firing turrets on the bow and stern so you can get more guns on target as long as you have room to turn them 360 degrees. Getting guns on target is easier with this battleship configuration than any other.

Design Tenets:

The Importance of Torpedoes:

Any ship can use torpedoes; however the most valuable assets to your fleets for torpedoes are the destroyers. Although cruisers can be armed with a strong torpedo armament, it is ill advised as they are considered capital ships. Although torpedo boats can be designed in greater numbers with more torpedoes, it is a poor investment for an otherwise poorly armed and armored ship which only has a speed advantage over the destroyer. Most heavy cruisers have medium sized torpedo armament of up to two ranks of triple tubes per side of the ship so that it can fire. The importance of torpedoes for destroyers is that it needs to be able to fire a spread from as many angles as possible and thus, the torpedoes must be accommodated for the best angles of fire and be centerline mounted. Cruisers use torpedoes as situational firepower to impede the advancing of enemy forces while retreating from the fight, to increase its damage output against bigger surface vessels and to make targets easier to hit with their guns by forcing them to sail to avoid the torpedoes. Pre-Dreadnoughts, Dreadnoughts and even some modern battleships had torpedoes; however only on pre-dreadnoughts and some dreadnoughts does this make sense. The modern battleship engages at ranges where torpedoes are only effective at melee self-defense ranges if destroyers get through the other defenses of a battleship. Dreadnoughts and Pre-Dreadnoughts engaged at comparatively short ranges to make it easier to hit each other with lower technology driving their gun directors. Also, if one of those ships couldn’t harm another, an underwater torpedo launcher would be the best way to hurt more protected enemy ships as most from that era had minimal torpedo protection. Only some super-dreadnoughts implemented torpedo protection by the end of World War I.

The Importance of Secondary Guns on Capital Ships:

It may be less accurate than your main guns to engage surface targets with smaller secondary guns, but it can actually help damage larger ships and help deter smaller ones from coming in range. Secondary guns can be as small as destroyer caliber or sometimes smaller depending on your technology. They can also be as big as light or even heavy cruiser strength if you are fully decked out as a top of the line super battleship. The more consistent you are with secondary guns in your design, or having more of the same gun on the ship, the easier it will be for you to target smaller enemies that might threaten your capital ships. It also helps for accuracy in the long run. The German Strategy for getting the main guns to hit the target is simple: Put shells on the target. By rapid firing the secondary armament, it can assist the main armament in dialing in their rangefinders to cause devastating results on the target ship. It also provides a way to target the smaller ships when your main guns would rather be busy on another target. Think of a single cruiser or battleship without secondary armament having to fight a small fleet of destroyers screening for a battleship or cruiser. You do not want to split targets with your primary armament for accuracy reasons and since you have no secondary armament you cannot target those smaller ships while focusing on the bigger threat. Thus you will have to prioritize the most immediate threat first. In this case, the destroyers would get the pounding while the enemy battleship idles away lobbing high caliber shells at your battleship with no ability to fire back without a drop in accuracy. If you focused the battleship though, which is the poor choice, the destroyers would launch torpedoes while trying their best to set fires and cripple your chance to fight back at the battleship or even sink you outright if you do not maneuver to avoid the torpedoes, which also hurts your fire rate. One could understand the lack of secondary armament if you were screened by destroyers or cruisers to focus the small fry, but without those, you need to be your own destroyer or cruiser while still being able to engage the battleship at long range. This is the reason why the secondary armament of capital ships is there when you need to focus on two targets of different priorities with no accuracy penalty.

Armor Schemes Matter – The Two Major Camps:

The armor scheme of your warship really matters. Especially with low technology, it matters to maximize armor while minimizing weight to use for other weapons or other fittings which could help you achieve victory. There are two camps due to both a World War I view and a World War II view. These armor schemes are called: Turtleback and All-or-Nothing. With the British Pioneered doctrine, turtleback armor gets you increasing hull armor from bow or stern to amidships where the armor is at its thickest, however since it is with the design philosophies of World War I where engagement distances were much closer, Turtleback has an Achilles heel – This is that the hull while strong has a weakness to plunging fire from the deck which can punch through and explode in the vital parts of a ship. The Turtleback scheme, no matter your hull material, will always weigh more because you end up sacrificing a lot for increased hull armor protection. Turret and conning tower protection is also sacrificed except for the largest and most expensive battleships. All-Or-Nothing schemes are pioneered by the World War II thinking of American Designers, by sacrificing bow and stern armor and only boxing in and internally up-armoring the essential areas that need protection from enemy fire all around. It can provide a higher level of survivability in combat with the same armor thickness than a comparable turtleback design. As such the overall weight of the armor is lighter, but still thick enough to deflect shells and protect against plunging fire. They also highly protect the fire control systems in the superstructure and all primary turrets to make sure that they are not easily knocked out. More advanced All-Or-Nothing schemes pioneered a triple deck armor layout that gave the enemy shell an arming point at the deck, while letting it bounce off the armored underdeck and explode in the non-essential part of the ship. By doing this, it prevented causing citadel damage or an ammo detonation. This design also comes with a caveat. Because the armor is focused only in the vital areas of the ship, other armor piecing shells hitting the bow or stern at a flat angle will over penetrate and cause flooding and without enough compartments to contain the flooding and efficient damage control precautions, the ship will still be sinkable. Torpedo protection and hull bottoms are also external belts of armor that is added to the existing citadel or to the keel which can assist in protecting the ship from torpedoes and provide more adequate protection from gun hits as well. All battleships and battlecruisers should have torpedo protection as torpedoes are a high threat to these capital ships.

Well, that about wraps up my blurb about ship design. However this is no definitive guide to how to design your ships in the game. I am simply providing a historical background to how in real life, naval architects designed such ships to fight for their respective navies to achieve supremacy. Good Luck and Happy Building!

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"Strategy should govern the type of ship to be designed. Ship design, as dictated by strategy, should govern tactics. Tactics should govern details of armaments."

J. A. Fisher,  1904

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Ok, your last line claims that you're giving historical background - I'll make some historical corrections (which also are valuable for in-game designs). Please don't read this as an attempt to undermine your post, only a means to correct it slightly where it isn't really right, and maybe complete it in places :)

 

On 1/23/2020 at 1:52 AM, BattleshipOfDestruction said:

The general design schematics of torpedo boats is that they are armed primarily with torpedoes and their auxiliary weapons are guns of a caliber of 5 inch or less. These auxiliary armaments are sparse, usually only a few turrets, because the main job of a torpedo boat is to deliver large spreads of torpedoes to the target while under fire.


True torpedo boats rarely carried guns bigger than 3'', and in numerous times not even that. I know that Germany produced some WW2 "Torpedo boats" with 105mm guns but those were the size of a normal destroyer of any other navy - they weren't torpedo boats in anything but name.

Torpedo boats stop being a thing more or less in the 1910s, a time by which destroyers completely take over all their "torpedo-bearing" roles for the remainder of the era. Most nations don't even have a torpedo boat hull after  1915 or so in the custom battle designer. So, they stop being a thing before they can truly "deliver large spreads of torpedoes" because for most of their existance they'll be restricted to single torpedo mounts - they may carry twins by the end of their viable life, but even then packing a lot of those is not really viable in hulls of historical displacement.

 

On 1/23/2020 at 1:52 AM, BattleshipOfDestruction said:

(Destroyers) They are more armored than a torpedo boat and are also a direct descendant from the previous ship class.


Both are incorrect. Destroyers barely carried any armor, even splinter protection out of gunhouses was rare, so they're equally armored to a torpedo boat. They aren't descendants from torpedo boats either, the "Torpedo boat destroyer", as they were born as, clearly implies their true origins: they were designed to chase off and destroy Torpedo Boats...not to replace them.

They ended up replacing them anyway but that was more of an evolutionary thing than an intentional one.

 

On 1/23/2020 at 1:52 AM, BattleshipOfDestruction said:

(protected crruisers) They were typically medium to heavily armored for their time and could hunt destroyers and rain down high explosive fire on larger fleet units to cause fires. Most protected cruisers had a main armament of 5 inch guns or 6 inch guns primarily in casemates

In what regards to armor, it's far more nuanced than that. Protected cruisers did not have any external armored belt - instead their side protection depended on a "turtle" configuration for the deck, where it's sides would be inclined down on the extremes to provide angled armor protection against side penetrations. Other than that, and coal bunkerage on the side compartments to slow down shells, they had no side protection at all.

Hence, it can barely be argued that this ships were "heavily armored" at all, when the other significant armor was put on the deck- which wasn't that thick either (2in in the flat areas and 4-5in on the sloped ones was more or less common).

Also protected cruisers carried far larger weapons than just 5 or 6 inches. guns in the 7-10in ranges could be regularily found aboard them. British protected cruisers had weapons up to 9.2'', for instance. The most extreme cases (japanese Matsushimas) saw a 13'' canet gun on a single mount. Largely impractical, but still goes on to prove that the kind of weapons used on those ships wasn't just a handful of light-to-medium caliber rifles.

 

On 1/23/2020 at 1:52 AM, BattleshipOfDestruction said:

(light cruisers) Some were built with armor that could stop destroyer caliber weaponry, other than the torpedo, while others could still combat against heavier cruisers with their armor being thicker than the other common light cruiser role. Some cruisers, both light and heavy were armed with "wing" mounted torpedoes.

Most light cruisers were built with armor to keep off 6'' guns (6'' being more or less the natural top-end weapon caliber for this class). Of course there were lighter ones with armor that even barely qualified for that (in particular the italian scout cruisers), but those were the exception, not the norm.

Also, most cruisers had torpedoes, not "some". The only nation that gave up on them as a matter of course were the americans, and it can be argued that their "light" and "Heavy" cruiser distinction was more nominal than anything else, because when it came down to displacement alone, all the non-torpedo bearing american cruisers displacements would put them in the "heavy" cathegory. The only real american "light" cruisers were the Omahas and Atlantas. Both carried  torpedoes.

 

 

On 1/23/2020 at 1:52 AM, BattleshipOfDestruction said:

The heavy cruiser was born out of the necessity to diversify the design of a cruiser after the protected cruiser design became obsolete. They are usually armed with 8 inch guns in dual or triple turrets, though single turrets were indeed common in the early years. These are the most likely cruisers to be able to combat larger fleet units effectively while still being a light cruiser killer of sorts. They are typically slightly slower and less maneuverable than a typical light cruiser, but that trade-off is in favor of increased armor to defend against other 8 inch armed warships. The 8 inch HE shells were particularly nasty to the superstructures of enemy battlecruisers and battleships, and also their less protected deck on the bow. These cruisers are able to set fires more easily due to the increase in caliber. They also frequently come armed with torpedoes, but that design decision is not set in stone, unlike a destroyer which survives on lots of small guns and torpedoes.


This is probably the entry with the most corrections needed. Let's see.

- the heavy cruiser was born out of a Naval Treaty. It was an artificial class born from established artificial self-imposed limits. Had no naval treaty happened this class would've never existed, certainly not as it did. One has to be very careful when talking about this class. With no treaties in place the light cruisers of the 1930s would've carried 8'' guns or bigger (The Pensacola class was classified as a light cruiser initially, with 10x8'' guns), and the heavy cruisers would've probably ended being lightweight versions of the WW1 battecruisers with 9, 10, 11 or even 12 in guns.

-There were very few heavy cruisers with single mounts. Top of my head the british Hawkins class only (the first two furutakas had 8'' in single mounts but were rebuilt with dual turrets pretty soon).

- Heavy cruiser armor was highly variable and increased through the years, but in no way we can say as a general statement tha they were "better protected than light cruisers". One only has to take a look at the comparative armor of a british Town class cruiser with that of a Pensacola - the "light" one has far better protection than the "heavy" one. Again, heavy cruiser protection was highly dependant on the displacement limit, and the fact that it had  to carry 8'' guns while light cruisers were limited to 6''. Carrying heavier weapons meant less displacement free for armor. Most heavy cruisers of the Treaty Era ended up being woefuly protected as a result, while light cruisers of the era almost always had balanced protection.

-and finally all heavy cruisers in all nations had torpedoes - except for the americans. They were the exception. A notable one, but the norm was to always mount torpedoes on cruisers, heavy or not.

 

On 1/23/2020 at 1:52 AM, BattleshipOfDestruction said:

The Battlecruiser is kind of a stepchild of a heavy cruiser and a battleship. It is a heavy cruiser killer that has the same speed and maneuverability as a heavy cruiser and slightly higher armor to combat those units, while having the big guns typically found on full battleships. T


No. Just no. The Battlecruiser is a very fast capital ship, faster than the normal battleline by an order of 4 to 7 knots, depending on the era. They were designed to act in the van of the battlefleet to wipe out enemy scouting forces and *THEN* either form a fast flanking force or form up in the van and rear of the main battleline, to duke it out against the enemy battleline in both cases. Fighting cruisers was part of their role, but wasn't their only role. Those ships were designed to fight capital ship actions too.

This could be achieved by reducing armor to cruiser level, but by no means it means it had to be done that way. Reducing the main caliber of guns and their numbers vs what was standard in battleships while keeping capital levels of protection was perfectly viable.

Those ships tended to be much larger than battleships too.

For instance, German Battlecruisers of WW1 had equivalent (and in some cases, superior) armor than contemporary british BattleSHIPS, let alone battlecruisers. Amagi class battlecruisers (as designed) had armor layouts at least comparable to those of most battleships of the era, if somewhat thinner, while sporting speeds of almost 30 knots (4 knots faster than their nagato counterparts, 9knots faster than the whole american battleline).

HMS Hood as completed was 7 knots faster than their battleship equivalent (the Queen Elizabeth class), yet had better armor and weapons. The catch?, she displaced 15000 tons more at full load. In fact she was arguably the first (can be debated the first were the german Derrflinger) "fast battleship". Battleships with cruiser speed.

Hence, to design a battlecruiser you don't have to underarmor it. Battleship armor thickness is perfectly valid. What makes a battlecruiser a battlecruiser is it's speed, far superior to that of same era battleships. The means through which you achieve that speed (sacrificing armor, weapons, both, or neither and going for a much larger displacement) is completely irrelevant.


 

 

On 1/23/2020 at 1:52 AM, BattleshipOfDestruction said:

Some dreadnoughts of Russian design even did away with the superfiring concept to allow for 360 degree turning center-line turrets to increase the number that can fire when angling toward and away from an enemy. The Japanese navy had a large number of dreadnoughts at their disposal at the beginning of World War II and frequently used them in combat to varying effect. The later dreadnoughts are somewhat on par with modern battleships, but even when modernized can be less effective at what they were designed for due to inferior guns and armor. Also their "Turtleback" Armor Scheme, which was popular for late-era dreadnoughts, were vulnerable to engagements at long distances. The super dreadnought is like a dreanought, but were a more stable platform to receive much needed upgrades in caliber (up to 16 inch) and armor against these guns.


The "russian" model wasn't russian. It was pioneered by the italians before them. And neither had 360 degree turning center line turrets, that's just incorrect.

The japanese had a large number of dreadnoughts at the beginning of World War II - compared with any other navy than the USN or RN, but they rarely used them in combat. The only japanese ships that saw regular combat were the Kongos, rebuilt WW1 battlecruisers. The rest of the japanese battleline rarely fired their guns in anger until the Phillipines campaign, 3 years into the pacific war.

Super-dreadnoughts were never a class. They were just dreadnoughts, just bigger than the original generation. Nothing special about that classification.

 

On 1/23/2020 at 1:52 AM, BattleshipOfDestruction said:

The All-Or-Nothing Armor Scheme became standard for most navies implementing modern battleships, however Germany and Japan did evolve the Turtleback armor scheme to include angled underdeck armor that would help deflect any debris from an incoming shell to protect from plunging fire which made them more survivable than existing super dreadnought designs

Uh. No. Japan gave up the inclined belt concept after their Nagatos (Yamato was a full AoN design). And the yamatos were the only "modern" japanese battleship design that got built.

And Germany stood with pretty much the same armor layout that was common in WW1 - incremental layouts and low laying main armored decks with sloped extremes to back the side armor. Those ships were terribly vulnerable against plunging fire, I don't know exactly what part about plunging fire comes from, but is incorrect. Scharnhorst, Bismarck and H classes were all ships with serious weaknesses to long range plunging fire and specially vulnerable to soft killing (due to the low laying deck and how large of a volume of the hull was out of the main protected area).

 

 

On 1/23/2020 at 1:52 AM, BattleshipOfDestruction said:

Whereas the Yamato had an enhanced Turtleback armor Scheme to protect against plunging fire


No. Yamato had AoN armor layout. I don't know where the idea comes from that she had a turtleback - but she did not.



This is getting quite long. Making a stop. Will go on later :).

 

Edited by RAMJB
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On 1/23/2020 at 1:52 AM, BattleshipOfDestruction said:

which is safer for angling or go completely broadside on to your enemy (where your armor is at its weakest point) you can end up limiting the amount of turrets able to fire at them by up to half. To make sure you only expose a small broadside and thus retaining an advantage to angling your armor, make sure all primary turrets have the best firing angles that you can design into it. This design decision is best for any Modern Battleship and Pre-Dreadnoughts. It is also ideal for Battlecruisers and Non-aggressive Cruisers. Time for aiming for the turrets on the opposite end of the ship takes slightly more time than Centerline mounted 360 degree Turrets.

Angling is not a thing. Just get it out of your head. REpeat with me: "Angling is not a thing. I should not give a damn about angling, because it will make me create wasteful designs."

It's true that at certain cases of end-on-firing ricochets tend to happen more. It's a current limitation of the game due to how the armor layout is currently modelled (something with at some stage will have to be corrected) and due to the gunnery hit chance modifiers still not accounting for bearing rates and range rates.

To put it in simple term: the bigger the bearing rate ,the harder finding a valid solution on you it is. If you're going nose in towards the enemy ,or at a high "angle" your bearing rate is reduced to almost 0. Meaning, the more broadside you give to the enemy, the more "lateral" displacement you'll achieve from his point of view, the far harder it will be for him to hit you. But if you come nose in your bearing rate is 0, and the enemy will have a solution in no time.

A second consideration is range rates. On an end on scenario (be it nose in, be it rear-out) your range changes quickly. Early analytic FCS had problems accounting for that. The problem is that most fleets went with synthetic FCS, which didn't give much of a damn about range rates. 

This is compounded by the fact that guns tended to spread more in distance than in bearning. Meaning, a full salvo landing pattern was an ellipse longer in range than in bearing. If you're nose-in, you're fitting your ship nicely and squarely into the dispersion pattern of the enemy salvo, guaranteeing more hits.

So in general terms - going nose in or rear out towards an enemy was pretty much giving away your solution for the enemy to drop shells on you, and makes their salvoes more likely to hit you. NOT GOOD. NOT GOOD AT ALL.

To top it off, this becomes even more relevant the longer the range. Deck hits don't give a damn about your relative "angling". Deck hits are deck hits - if your deck is enough to bounce shells off all fine and dandy (as long as your main armor deck is high enough on the ship - turtlebacks are going to get trounced). If it is not enough, you're going to eat a shell into your vitals, no matter if you're nose-in, rear out, full broadside, or dancing a polka.

Finally the nail in the coffin is that armors thick enough to cause ricochets were only present in the waterline area (something currently not modelled in game). The rest of the hull was less protected with far thinner armor, which would not be enough to bounce off big caliber shells no matter the angle. By going in you're asking to get a shot through your nose and directly into the guts of your ships (Where your transversal bulkhead -again still not modelled in game) might, or might not be enough to stop it. But even if it does stop it that means a shell going off inside your ship. NOT GOOD.


So repeat with me once again: "Angling is not a thing. Angling will get me killed. When engaging with an enemy I want to give them the hardest shot possible, because if I get hit it's not going to be good, which means maxing out my bearing rate, which means going broadside on. Angling is not a thing". 


Now, I know most of what makes that true is not yet in the game. End-on firing is unrealistically represented at the moment and "angling" kind of works atm. Keyword is *YET*. Developers are on record stating the armor model needs a rehash, and gunnery modifiers at some point will have to be included to properly represent FCS guided gunnery (meaning modifiers for bearing and range rate vs the kind of FCS used, analytic or synthetic). Once those are in the game, you can forget about angling because it's going to get your ships killed.


Also, and I'll have to insist on it, 360º turrets were not a thing in capital ship construction. At all.

 

 

On 1/23/2020 at 1:52 AM, BattleshipOfDestruction said:

Although cruisers can be armed with a strong torpedo armament, it is ill advised as they are considered capital ships.

Uh, no. Cruisers are cruisers and capital ships are capital ships. There's a lot of merit in putting torpedoes on cruisers. It's a tradeoff because if hit, those torpedos will tend to explode (not yet modelled in the game, will be in the future). There's nothing incorrect in NOT putting torpedoes in your CAs... but it's not "ill advised" to put them on either.

 

 

On 1/23/2020 at 1:52 AM, BattleshipOfDestruction said:

One could understand the lack of secondary armament if you were screened by destroyers or cruisers to focus the small fry, but without those, you need to be your own destroyer or cruiser while still being able to engage the battleship at long range. This is the reason why the secondary armament of capital ships is there when you need to focus on two targets of different priorities with no accuracy penalty.


One would not understand the lack of secondary armament even if screened by friendly forces. Main batteries in ships of the time had a quite limited ammount of shells in the magazines. Usually ranging from 80 to 100 rounds per gun. Assuming a rate of fire of one round per minute that means that in little more than hour and a half of sustained fire, you'll be out of rounds for good. If you shoot at small buggers, those shots are not fired at the big buggers. Meaning: you're wasting your main caliber shots.

To compound it magazines had a limited ammount of shells per tipe. To simplify it let's say you had 80% AP, 20%HE (it's a VASTLY and GROSS simplification of both the distribution and the kind of shells involved, btw). Meaning, once you expend your HE shells (in this case assuming a magazine size of 100 rounds per gun, it'll be 20 rpg), you'll be firing AP to destroyers. Not that destroyers take either HE or AP well (overpens from large caliber guns were massively damaging anyway), but once again - a huge waste.

On the other hand, Big caliber guns have a barrel life that (depending on caliber, shell weight, and muzzle velocity) would range from as low as 100 shots to up to maybe 300-ish. At any rate each time you fire your main guns that's one more shot into your barrel life, and one less shot until the next barrel replacement or relining. Otherwise the barrel would degrade up to the point where you might end up shooting blanks all across the place with no accuracy whatsoever.

Barrel wear treatment was simple in theoretical terms: either the barrel was relined or replaced. Relining a barrel could range from expedient and not very expensive to a nightmare: depending on the guns, some were FAR more complicated to reline than others to the point that relining was not worth it. Rebarelling meant a whole new barrel. Expensive by default.

Both needed time in a port with the appropiate installations, equipment, and workshops. Might not be a problem for some nations, might be a huge handicap for others.


In the meantime secondary guns had barrel lifes that went from hundreds to thousands of shots before new barrels were needed (it usually wasn't worth it to reline a 5'' gun, for instance). Replacing barrels was far easier because of them being far smaller and lighter, which could be done in places not as well equipped.


All this translates into: if you're forced to shoot at small DDs with your main guns because you have no secondaries, you're doing something seriously, SERIOUSLY, wrong in your design. 

 

 

On 1/23/2020 at 1:52 AM, BattleshipOfDestruction said:

These armor schemes are called: Turtleback and All-or-Nothing.


No. It's incremental vs All or Nothing.

Turtleback is simply a design layout where the main armored deck has sloped extremes. It can happen in All-or-nothing layouts. And in fact some DID happen in AoN layouts - the Nevada class had a turtleback, for instance. But it's counterintuitive because turtlebacks are terribly vulnerable at long ranges while AoN designs are, naturally, designed to fight at long ranges. So in the end turtlebacks in AoN designs dissapeared.

Incremental armor means putting different thicknesses of armor across different areas of the ship. All or nothing meant that nothing out of the main armor area would receive any armor, other than splinter protection. Implied was the need of the AoN layout to provide for a large enough citadel as to support the whole ship and allow it to float even if all the other areas were flooded as long as the citadel was not breached, and hence, flooded (what's called the "citadel raft" concept), which is a very big point central to AoN designs wich incremental designs never had to worry about.
 

 

On 1/23/2020 at 1:52 AM, BattleshipOfDestruction said:

More advanced All-Or-Nothing schemes pioneered a triple deck armor layout that gave the enemy shell an arming point at the deck, while letting it bounce off the armored underdeck and explode in the non-essential part of the ship. By doing this, it prevented causing citadel damage or an ammo detonation.

This was not new, and was't exactly pioneered by AoN designs, even while it's true that AoN designs exploited it to the best, because the incremental&turtleback layout natural vulnerability to soft killing due to the protected areas being very low on the hull.

 

 

On 1/23/2020 at 1:52 AM, BattleshipOfDestruction said:

They also highly protect the fire control systems in the superstructure and all primary turrets to make sure that they are not easily knocked out.


Fire control systems weren't located in the superstructure. Or rather, properly designed FCS weren't. Rangefinders were on the superstructure of the ships (and on turrets too). Directors for gunlaying were both in superstructures and in turrets aswell. Neither were fire control systems - they were gun laying and rangefinding equipment.

The Fire Control Systems was the main center of the system where all the plotting equipment vital for accurate centralized fire was placed. That center was placed well within the hull (sometimes even below the waterline), behind the solid protection of the citadel.

It was called the "Trasnmitting station". Inputs would come from the rangefinders and directors on the ship to the transmitting station, there solutions would be calculated and sent to the turrets for central fire. If you wanted to knock the FCS of a ship you had to go through it's citadel armor. Or, alternativelly, completely severe the connection between the transmitting station and the guns (which is the most likely reason why Bismarck's FCS went off, the vital cabling going to and from the transmitting station had to go through areas of the hull out of the main citadel - even while those links ran through armored paths themselves, they were rather exposed to enemy fire. And Bismarck's turtleback layout meant those paths had to go through a far longer unprotected area than in AoN designs with armored decks being much higher and covering far larger volumes of the hull as a result)

Knocking out rangefinders and directors would be damaging, but would not KO centralized fire. Specially because some of those directors and rangefinders were placed on turrets themselves (behind very heavy armor themselves) and were very hard to knock out.
 

On 1/23/2020 at 1:52 AM, BattleshipOfDestruction said:

Because the armor is focused only in the vital areas of the ship, other armor piecing shells hitting the bow or stern at a flat angle will over penetrate and cause flooding and without enough compartments to contain the flooding and efficient damage control precautions, the ship will still be sinkable.


No. If a ship had an AoN scheme, it was using, by default, the citadel raft approach. Even with all out-of-citadel floodable areas flooded, the ship would have still a very large flotability reserve to keep the ship afloat. Barring capsizing, It was impossible to sink an AoN design without breaching it's main citadel area and flooding it too.


Phwew...that was long. I left some things out because of being debatable in a given context, but I have just so many time :). Hope that helps to complete the OP's exposition :).

Edited by RAMJB
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Yamato, Tone, and Mogami all had "turtlebacks," in the sense that their armored decks curved down at the sides. This was not comparable to the turtleback on, say, Bismarck, in that the curve connected to the top of the heavy belt armor.

Here is the layout on Tone, per Japanese Cruisers of the Pacific War. There was no curved deck over the magazines (the right-hand image).

xlGKPGx.jpg

Mogami's layout was essentially the same, though with a thinner deck slope (60mm) and thicker flat deck (35mm). Yamato's deck had less slope angle.

 

I am unsure why this layout was adopted. References do not say the reason. Some simplistic calculations show this layout saved some weight on Mogami and probably Yamato, but it was likely about weight neutral on Tone. It likely reduced topweight, although I haven't done the math. It may have also made the connection with the sloped belt simpler. The effects on overall armor protection are complicated.

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Well that's kind of the thing, right?. If it isn't a turtleback, well then...it isn't a turtleback and should not be qualified as such ;).

As for the reasoning behind why it was done, I think that the designers realized that the only way to form an armored enclosed "box" with the main armore deck at that height, was to slightly slope down the deck in order for it to meet the top of the armored belt. Had the deck been "straight" all the way instead, the deck immediately below the armor deck would've been lower than usual, while the deck level of the armored deck itself would've been higher. It also would've meant a slightly lower volume of the ship within armored protection when for almost no weight cost, you could raise the deck a bit and get a higher volume of the hull under citadel protection. Which is not a bad idea on itself. 

A picture of Yamato's layout can help so I'll attach one. At any rate, no, that's not a turtleback at all. At least it's not what it's commonly known as such so let's not call things for what they're not, to stave off confusion ;).

as for why was done in Tone, you only have to see your first illustration. Without that "sloping out", the top of the machinery would've been left out of the armored deck level. The japanese had to

a) accept an unarmored gap between the armored belt and the main armored deck, and place that deck higher to cover the machinery (unnaceptable)

b) accept part of the machinery left out of the main armored area (unnaceptable)

c) raise the belt to the same level of the armored deck (needing a lot more weight for the armored belt, or reducing it's thickness for the same weight, both unnaceptable)

Or, finally:
d.)  do what they did: emplace the exterior parts of deck in a slope down for it to meet the main belt and produce a fully enclosed armored "box" that covered the whole machinery areas, resulting on a slightly larger vulnerability at longer ranges, but guaranteeing protection for the machinery. It's the sensible choice through and through, so it's normal they did it that way.

 

qkfXNHB.gif

Edited by RAMJB

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Let us not quibble about the definition of "turtleback." It is a curved deck, I suppose we can agree. I guess I was thinking of the curved decks on the original destroyers, which are usually termed "turtlebacks" in references. The best technical description would be a deck with heavily cambered outboard strakes.

HMS_Fame_(1896)_IWM_Q_021241.jpg

 

 

2 hours ago, RAMJB said:

c) raise the belt to the same level of the armored deck (needing a lot more weight for the armored belt, or reducing it's thickness for the same weight, both unnaceptable)

This the approach I used in comparing weights. Unfortunately it seems I did the math wrong on Tone. Here it is, corrected:

For Tone, with a slope of 2.9m at 15 degrees, a slope thickness of 65mm, a flat deck of 31mm, and a 100mm belt at 20 degrees, and assuming a steel density of 8g/cm^3, the following calculations can be made:

  1. The weight of the angled deck section is about (290cm*6.5cm*8g/cm^3) = 15.08kg/cm (of length) per side.
  2. Additionally, there is 18mm structural plating extending 0.751m up to the level of the flat deck, adding (75.1cm*1.8cm*8g/cm^3) = 1.08144kg/cm.
  3. The total weight is thus 16.16144kg/cm per side.

If the ship had a more conventional design, with the flat deck extending outward more (without camber), and the belt extending up to the level of the flat deck:

  1. The flat deck would extend (2.801m+0.273m) = 3.074m further out. It would weigh (307.4cm*3.1cm*8g/cm^3) = 7.62352kg/cm more.
  2. The armor deck (edit: belt) would extend 0.751m farther up, replacing the structural plating; along its own axis (as it has a 20 degree slope), it would extend 0.799m. It would weigh (79.9cm*10cm*8g/cm^3) = 6.392kg/cm more.
  3. The total weight would thus be 14.01552kg/cm per side.

So on Tone, the curved deck adds 2.14592kg/cm per side. Given that Tone's machinery deck extended about 76.8m, the angled deck (vs a conventional design without camber) with the same 20 degree 100mm homogeneous belt cost approximately (2*7680cm*2.14592kg/cm) = 33 tonnes. Why was this preferable? Can structural weight savings explain this away...?

Edited by disc
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11 minutes ago, disc said:

and the belt extending up to the level of the flat deck

that's the thing. If you want the belt extending up to the level of the flat deck you're going to need a lot more weight of belt armor to extend it upwards with it's nominal thickness, to thin it down so with the same total weight you cover that extra area, or a mix of both, adding a bit of extra weight while giving up a bit of protection simultaneously.

Your calculations show that the sloping of the deck meant it ended up being heavier than a flat one. No suprise there - but you're not calculating how much weight you save in belt armor you don't need to add...or the extra protection you're retaining by not thinning it down to keep the weight the same :).

Edited by RAMJB

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16 minutes ago, RAMJB said:

No suprise there - but you're not calculating how much weight you save in belt armor you don't need to add

Yes, I did.

28 minutes ago, disc said:

The armor deck would extend 0.751m farther up, replacing the structural plating; along its own axis (as it has a 20 degree slope), it would extend 0.799m. It would weigh (79.9cm*10cm*8g/cm^3) = 6.392kg/cm more.

This is the amount of armor required to cover the same vertical space as the sloped deck, at the same 100mm thickness and same 20 degree slope, meeting our new flat deck at its outboard extremity.

 

So I think there must have been another reason for the cambered deck. Possibly it was desired to strengthen the outermost deck strake. To get the same weight, the conventional layout could have an outermost strake of ~39.7mm. It may also have been more difficult to penetrate at the expected engagement distance of the ship; possibly there are structural reasons, as I have alluded. I'll have to check if Ducol steel, CNC, and NVNC differed in densities, but I don't think they did by very much.

Edited by disc
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uhhh I totally misread that paragraph you quoted, but that's because you labelled it wrong. You're mentioning armored DECK...you're extending the armored BELT there ;). I somehow thought you were substracting the angled portion of the deck from the total. I didn't check the calculations, only the final number. My mistake.

It would read like this:
 

28 minutes ago, disc said:
  • The flat deck would extend (2.801m+0.273m) = 3.074m further out. It would weigh (307.4cm*3.1cm*8g/cm^3) = 7.62352kg/cm more.
  • The armor BELT would extend 0.751m farther up, replacing the structural plating; along its own axis (as it has a 20 degree slope), it would extend 0.799m. It would weigh (79.9cm*10cm*8g/cm^3) = 6.392kg/cm more.
  • The total weight would thus be 14.01552kg/cm per side.

The caveat is that in this, then, you're not substracting the sloped deck weight?. You're adding a straight extension to the deck, you're adding up extra belt height, but you're not taking away the inclined portion of the deck you are substituting with the straight deck extension?.

Sorry if I'm missing things here, I'm doing seven times simultaneously atm and is hard to focus on one alone ;).

Edited by RAMJB
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Ah, OK I see now what you mean. You say that with the "straight deck, extended belt" you'd save weight. I COMPLETELY misread your post. Again, my apologies, I should really focus on doing one thing at a time.

I'll come back to this post later on and read it properly. This is a good proof that after a long day having half a dozen internet tabs open simultaneously is not really good for your brain XDDDDD.

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Oh yeah, sorry. My mistake. Poor labeling is the bane of many things, yes?

Anyway, there must have been a good reason for this armor layout....

 

 

 

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17 minutes ago, disc said:

Oh yeah, sorry. My mistake. Poor labeling is the bane of many things, yes?

 

You tell me, lol. Been victim of miswording things so many times by now, I know the feeling very very well hehehe.

Anyway back on topic.

The reason why the "straight deck" calculation ends up being lighter is easy - because the inclined deck is 65mm thick. The straight extension would keep the same thickness as the straight deck, 31mm, ending up being much lighter as a result even with the cost of adding extra belt.

So why was this done?. I think it's because in order to extend the belt upwards you'd also have to either reduce the angle of the belt to keep the same beam, or increase the beam of the ship (as, being inclined any extension would add beam).

I think the japanese didn't want to do that because the first option (reducing the belt angle) would end up in weaker protection by the vertical armor. And the second option would mean all the upper decks (up to the weather deck) would've had to be beamier too, and probably the whole cost of the extra structures for a beamier ship would've heavily outweighed any weight saved in that particular area with a thinner straight deck.

Also adding beam over the waterline tends to make ships more unstable - and after the 1935 typhoon disaster the japanese were very self-aware about topheaviness and stability in their designs.

So I just suspect the japanese wanted to extend the vertical protection of the ship without adding any belt that would've caused the ship's beam increase avobe the waterline, while keeping that vertical protection in that area similar (actually is better when you account the very sharp angle) to that provided by the belt itself, but get it done by the angled deck instead. Basically retaining vertical protection without extending the belt armor. So they went with a "protected cruiser" layout inside, if you get what I mean.

I don't think it really has too much to do with structural strenght. A layout not that different from this one was used in Mogami and that one really didn't care about structural strenght at all (at least not until the refits).

Edited by RAMJB
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Yeah, too much special magic being assigned to the term “turtleback” in the OP.  Just look to contemporary writing:

Quote

It is perhaps proper to add that the armour deck beneath the lower deck had the turtleback form then common to all protected cruisers.

https://books.google.com/books?id=wTU8AQAAMAAJ&pg=PA942&lpg=PA942&dq="turtleback"+AND+protected+cruiser&source=bl&ots=ceLIGIYOoX&sig=ACfU3U2gaJ3zsbEvEIZx-EVuuU6agrQ6Xg&hl=en&sa=X&ved=2ahUKEwit-6et_J3nAhXCZs0KHU_5CFkQ6AEwF3oECAsQAQ#v=onepage&q="turtleback" AND protected cruiser&f=false

 

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You forgot about Large/Unrestricted/Super cruiser

Alaska class -  the only class of ships of this type to be built (which was not a battlecruiser as some wrongly try to label it). Gives you a good idea how a "heavy" cruiser could look like if there were no treaties.

Deutschland was pretty much an unrestricted cruiser altough by treaty terms it was considered a (extremly restricted) capital ship. It can be also seen as the last armored cruiser ever built as it shared pretty much all its characteristics and weaknesses. 

You actually forgot about Armored Cruiser too which i realized now. 

Anyway i smell a world of warships ##$!@$$ ehm player.

 

Edited by Microscop

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What does being a "World of" Player got to do with anything relevant here. I was a WoWs player at one time or another and yes the implementation of historical warships was no where near the way it should be which is part of the reason I quit that game; that fact combined with the terrible business practices of the Wargaming devs which I hated with a burning passion. Again, this is besides the point.

Mainly what I am saying is that a lot of the information I have about warships is old and fragmentary considering a lot of the books I have are out of print from the 1950s and 60s and what my grandfather who served on USS Kimbery (DD-521) knew about naval ship design from what he told me about the pacific war. Some historians of that period weren't as accurate as they could of been and that is partially what is at fault here.

Thank you to everyone for your feedback on the points I got wrong and I hope I will do better next time.

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Now, I do have to point out a couple of things which may be relevant here:

- The Conti di Cavour and Andrea Doria classes of Italian Regia Marina did, in fact, have the ability to train their midships triple 305-mm turret through 360 degrees. This is if memory serves me correctly, which I think it does.

- It would be interesting for you to note that the deck slope present in Mogami's layout forms a perfect 90-degree angle with the 20-degree sloped belt.

- And finally: angling, funnily enough, is a thing. This is probably the kicker for some of you, but it's true. It's not World of Warships-style angling ("Turn 30 degrees in and I'm immune!") - but it is angling. Increasing the relevant thickness of your protection in relation to incoming fire has always been a thing. Otherwise, you should ask the Germans why they designed Scharnhorst and Bismarck's armour and gave her expected battle ranges based on a 30-degree target angle, or why the Americans built their protection for their Washington cruisers with an eye towards immunity to 203mm gunfire at a 60-degree target angle (later a 90-degree target angle, which is in fact a flat broadside presented to the target). In each case, it's based on the fact that you will almost never have a parallel course with the enemy surface combatants - you will be fairly always be moving away from or towards the target, so you can choose to protect your ship on a more reasonable weight than it otherwise might be.

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On 1/22/2020 at 5:52 PM, BattleshipOfDestruction said:

 

The Dreadnought/Super Dreadnought:

So named after the original semi-dreadnought named HMS Dreadnought,

Uh, what?

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