Realistic Ship Classification

This guide will help you determine what classification your vessel falls under, based on both historical and modern warships as it applies to From the Depths. Also, some usage and design recommendations.

Preface

Welcome to the finally revamped Realistic Classification Guide! Note that I am not a historian of any kind and am largely compiling information from online, so inaccuracies are likely, but I do try to generalize to minimize their effect. Metrics are given in FtD terms.

Additional Notes
Concerning Torpedoes: Torpedoes are a very multipurpose weapon in FtD. Throughout this guide references are made to both anti-ship and anti-submarine torpedoes. You can choose to ignore realism and make both the same way, but here’s a good way to differentiate the two if you wish to:
Anti-ship or traditional torpedoes should have their ballast tanks set to a static, fairly shallow depth between 3 and 10 metres. This will make them capable of targeting enemy surface vessels, but incapable of targeting the usually deeper submarines. Anti-submarine torpedoes can have neutral ballast tanks so that they are able to hit a submarine at any depth.

Concerning Speed: The speed a given vessel is capable of in FtD can easily be far faster than their real life counterparts. Rough estimates are given throughout this guide, and relate almost solely to FtD rather than real life metrics, except for where relative speeds are concerned; i.e.: battleships are slower than destroyers, but may still travel faster than most real life destroyers.

Concerning Size: Any size estimates given should be considered as a minor factor in classification. If your light cruiser is larger than your heavy cruiser, so be it; its intended purpose, speed, and armament are more important. However if you have a particularly well armed destroyer and a smallish light cruiser that are similar in armament and speed, the larger one is more likely to be considered a cruiser rather than a destroyer.

Concerning Cost: Any cost estimates are very rough and are almost always going to be relative. The cost of your vehicle is not nearly as important as its intended role. You can easily have a highly advanced destroyer that costs more than your heavy cruisers, if probably a tad inefficient.

Terms

These are a few terms that may not be totally clear to someone that isn't me, or may need a little extra explanation when referenced.

Depth Charge - A missile with no active guidance or maneuvering capability, using ballast tanks and magnets to target underwater vessels.
Mine/Bomb - A missile with no active guidance or maneuvering capability, using magnets to target surface vessels
Drone Craft - A vessel that is small, cheap, and mass producible, with little onboard material storage or detection, usually relying on a carrier or flagship to provide these instead.
Low-caliber gun - APS that is <~300mm short shells or <~200mm long shells, or CRAM cannons <~1500mm.
High-caliber gun - APS that is >200mm with long shells or >300mm, or CRAM cannons >1500mm.
Anti-air weapons - Weapons specifically designed to target smaller, more evasive aircraft. These usually have fast shells, use HE, flak, or frag warheads, and often make use of timed or altitude fuses.
Light anti-air - Anti-air simple weapons or low-caliber APS, generally firing fairly rapidly and usually trending towards using HE, frag, or HEAT to score damage with direct or near hits.
Heavy anti-air - Larger low-caliber or smaller high-caliber APS usually using HE, flak, and/or frag to deal good damage even without direct hits. These tend to fire slower than but can still have comparable fire rates to light AA.
Dual-purpose gun - A gun capable of effectively firing at both surface threats and aircraft. Usually these guns are not as effective against armored targets, but with the benefit that they can serve in multiple roles without taking up extra space. They will often use dual-purpose shells effective against both target types or use ammo intake management using ACBs to switch between ammo types depending on the target.
AMS - Anti-Munition System; generally referring to missiles or torpedoes using anti-munition guidance designed to destroy enemy missiles and torpedoes.
CIWS - Close-In Weapon System; an APS designed to deal with incoming missiles and/or CRAM shells, and sometimes also able to serve as anti-air.

Torpedo Boat

Any ship designed to carry only torpedoes as anti-ship armament.

These will generally not perform well alone against large warships, and are often used in groups or with larger ships that can draw fire. They should be fairly cheap so as to not be a huge loss should one be destroyed, while still being effective for their size against larger ships. They may posses one or several light AA guns for basic protection from aircraft or other small, lightly armored ships, and potentially a single low-caliber gun for additional firepower and utility.

Estimated Volume: 1,000-5,000

Frigate / Destroyer Escort

A small, cheap vessel carrying both anti-submarine weapons (depth charges and/or torpedoes), and no more than two low-caliber guns, with the intended purpose of acting as submarine protection to their larger destroyer cousins, and sometimes convoys or other warships.

A frigate is a powerful starting unit, as one equipped with torpedoes can damage larger warships plenty, with the help of its guns.

Note: Frigates, Destroyer Escorts, and Sloops serve the same role, however the term Sloop is anachronistic in a WWII setting, as this classification stopped being used for Anti-Submarine vessels starting during WWII. Frigates are generally considered to be cheaper to build and maintain than Destroyer Escorts, but perform their role just as well.

Estimated Volume: 2,000 - 5,000

Corvette

A small, fast, cheap vessel designed primarily to target underwater targets using either depth charges or torpedoes, and is otherwise very lightly or unarmed.

Real life corvettes would have used exclusively depth charges, but as torpedoes are far more viable in FtD, there is little separating a corvette from a torpedo boat in-game. If you are unsure what your vessel classifies as, ask yourself if it’d be a significant loss of materials to lose one. If so, it’s more than likely closer to a corvette than the far more expendable torpedo boats.

Estimated Volume: 2,000 - 5,000

Submarines

Any vessel capable of and primarily operating while submerged. A few subclasses of submarine exist:

Ballistic Missile Submarine - Submarine armed primarily with either custom nuclear missiles, or large/huge missiles. They often operate at very long range and primarily attack large surface targets.
Estimated Volume: 5,000 - 30,000

Cruise Missile Submarine - Submarine armed primarily with small/medium missiles to attack surface/air targets from long range.
Estimated Volume: 2,000 - 25,000

Attack Submarine - Armed primarily with torpedoes or specifically designed underwater turrets employing supercavitation bases on their shells. These may also include a number of missiles, and should primarily attack surface-level naval vessels or occasionally enemy submarines at relatively short range.
Estimated Cost: 1,000 - 20,000

Submarines have the benefit of being difficult to target for many types of vessels, making them perfect for use against more powerful enemy forces while minimizing damage.

Monitor

A small ship with a single high-caliber turret and heavy armor meant to engage much larger ships. The most important distinction from other ships with single main-caliber guns is that fitting the gun onto the cheapest, smallest ship feasible is the main design focus. These are most often used for shore bombardment in real life, but translate well to long-range artillery in FtD.

A monitor in FtD will often have a massively oversized turret, often using 300mm+ APS or large CRAM cannons/DoomCRAMs that cost more than half of the overall vessel. By cutting out the excess size costs seen in the usual large warships that employ turrets of this caliber, a monitor can be a powerful early-game vessel.

Estimated Volume: 5,000 - 10,000

Destroyer

A fast vessel with several low-caliber turrets, torpedoes, and light anti-air weapons, or occasionally a couple of heavy anti-air, depending on its intended fleet role. Often equipped with anti-submarine armament such as torpedoes or depth charges, minesweeping equipment, and rarely with mine-laying equipment. A large number of destroyers also featured dual-purpose main batteries, vastly increasing their anti-aircraft capabilities.

Destroyers are generally useful as the main workhorse of an early-game fleet, as their varied and numerous armament makes them useful against a variety of targets. In the late game destroyers may be useful as “minesweepers”, ships with sonar decoys and a wealth of torpedo AMS to protect larger ships from the often devastating torpedoes that late-game ships employ, or as anti-aircraft screening vessels to swat down aircraft so that your capital ships don't need as much of their own.

A more modern style destroyer may feature only one or two rapid-firing low-caliber turrets, and focus more heavily on torpedoes and guided missiles.

Estimated Volume: 5,000 - 12,000

Gunboat

A gunboat is any sort of vessel which has the main role of bombarding land targets rather than naval combat.

A gunboat would have larger turrets that may fire at a lower muzzle velocity, making it more effective against surface targets but less effective when hitting a moving vessel. A gunboat would likely have less armor than most larger combat vessels, and wouldn't need to be particularly fast.

Estimated Volume: 5,000 - 10,000

Artillery Ship

Often referred to as "Frontsiders" in FtD, no particularly good comparison exists in real life. These are ships with weapons mounted without turrets that must bring their nose to bear on the target to fire. These ships usually have a small number of powerful guns, and are usually able to turn on the spot.

Artillery ships can be incredibly effective, as their armor can be concentrated on the front of the ship and save costs on armoring the rest. They are generally weak to very fast ships that can change their bearing faster than the vessel can turn, but they excel against much larger targets than themselves, often benefitting from a small front profile that reduces the hits they take.

Since no good examples exist, naming conventions may include DDA (Artillery Destroyer), CAA/CLA (Heavy Artillery Cruiser/Light Artillery Cruiser), BBA (Artillery Battleship), etc.

Estimated Volume: 5,000+

Cruisers

Large, relatively expensive ships able to take on most opponents, or run from those they can't, with powerful guns and anti-air weaponry. Light cruisers in particular may also mount torpedoes to increase their effectiveness versus heavy armor. Cruisers may even be used to field one or two smaller aircraft, although usually without a means of re-boarding without the help of a crane. These ships are often divided into two categories:

Light Cruiser - A cruiser equipped with low-caliber guns, a mix of light/heavy anti-air, and often some amount of torpedoes.
Estimated Volume: 12,000 - 25,000

Heavy Cruiser - A cruiser equipped with high-caliber guns, and medium/large/huge missiles.
Estimated Volume: 20,000 - 40,000

Cruisers are the main workhorse of mid-late game fleets, being able to take on most targets and serve many roles from attack to defense. They should be balanced in their performance, having a speed of at least 15-20 m/s, fairly heavy armor (especially in the case of heavy cruisers), and plenty of firepower both against ships and aircraft. They can also be a huge help to a fleet that is otherwise lacking in anti-air firepower.

Modern Guided Missile Cruisers see less differentiation between light and heavy, since more powerful anti-ship missiles make even fairly heavy armor largely obsolete. With both types mounting only one or two main turrets, the main difference would be the size/amount of missiles mounted, with light cruisers preferring mostly small/medium missiles and a very small amount of larger missiles, while heavy cruisers see far more large/huge missiles while smaller missiles are used primarily against aircraft.

Carriers

Any large vessel designed to field and/or support smaller vessels.

While real-life carriers are characterized by the ability to take-off and land aircraft, a few extra roles exist for them in FtD since aircraft do not actually need to do these things specifically, although many people like to simulate these actions using tractor beams.

Escort Carrier - A smaller, lightly or unarmed carrier primarily serving as a transport for resources that a fleet of aircraft or drone ships need to operate. Escort carriers historically were as cheap, small, and fast as they needed to be to protect and keep up with convoys.
Estimated Volume: 8,000-30,000

Fleet/Fast Carrier - A large ship designed to support its aircraft or drone ships using offensive turrets and/or defensive CIWS, LAMS, and AMS. They are fast enough to keep up with fleets of battleships or cruisers, and can field a much larger number/more powerful selection of aircraft than smaller escort carriers. They may also include landing pads for helicopters.
Estimated Volume: 15,000-50,000

Amphibious Assault Ship

A vessel designed to transport land vehicles, and provide some amount of support near the coast.

While mostly useless in FtD with land vehicles being pretty pointless on Neter, if you want to try something different you might experiment with combined arms. Such a ship should have some excess material storage, as well as perhaps being equipped with anti-air or shore-bombardment weaponry. For realism, you’ll want to have any land vehicles that such a vessel transports docked via tractor beams, otherwise you can simply designate the land vehicles as amphibious so that the game will allow them to move across the ocean with the transport.
Estimated Volume: 10,000-30,000 (Not including drones/transported vehicle)

Fleet Protector

A vessel made specifically to protect other ships from missiles, torpedoes, and CRAM shells, with little to no offensive armament, and may be equipped with repair equipment.

While real modern warships often come equipped with some form of CIWS, it’s not always practical to have an effective one on every ship in FtD. Fleet protectors can often also serve as effective anti-air for a fleet that otherwise lacks this ability, employing dual-purpose lasers or APS in a CIWS role. They may otherwise be equipped with long-range LAMS or powerful AMS, as well as often toting powerful decoys to draw enemy missiles towards the craft, which is much more capable of handling them.

Once again "Fleet Protectors" do not necessarily exist in real life, but frigates or converted civilian ships may be fitted with various forms of air defense equipment or CIWS to provide cheap methods of covering friendly troops and vessels. Some designations may include FFD (Defense Frigate), DE (Destroyer Escort, another term for some modern guided missile frigates), or FFG (For guided missile frigates, especially in an air defense role). Larger, cruiser sized guided missile or CIWS vessels may be CG or CD.

Estimated Volume: 5,000 - 20,000

Pocket Battleship

A vessel mixing the strengths of heavy cruisers and battleships. They are heavily armored, with 3 or more high-caliber gun turrets, and low-caliber secondaries often mounted to the sides of the superstructure. They are big, expensive, and often somewhat slower than a cruiser, but tote more firepower and armor to make up for it.

Given that only three ships were ever classified as pocket battleships, the real life definition is very vague, making classifying it in FtD an even greater challenge. A pocket battleship can be considered a battleship with a higher than usual speed, slightly less armor, and a small tradeoff in the weapons department. It usually won’t have an incredible amount of anti-air, but should be expected to be able to take on any surface vessel smaller or less expensive than itself.

Some experts say there is no notable distinction between a Pocket Battleship and a Battlecruiser (see next section).

Estimated Volume: 20,000-40,000

Battlecruiser / Fast Battleship

A heavily armed, fast, and lightly armored vessel. It should be able to keep pace with a cruiser, and rely on speed and maneuverability to last against enemy vessels.

The viability of real life battlecruisers was and is heavily debated, as the tradeoff in armor for speed meant that they were vulnerable to enemy battleships, a vulnerability that was only slightly compensated for by its speed. In FtD it’s easier to provide a vessel with both adequate armor and speed, so a battlecruiser should be seen as a vessel with armament rivaling a battleship, and speed similar to a cruiser, around 15-20m/s, but likely not as heavily armored as a battleship.

The main goal of battlecruisers was to exploit the slow speed of enemy battleships in order to avoid the enemy's more powerful modern warships while chasing down weaker and older interwar or WWI era warships, that had little hope of damaging the battlecruiser's armor.

Estimated Volume: 20,000-40,000

Battleship

Pre-Dreadnought
WW1 era battleships had just one focus: get as many big guns as possible floating. Pre-dreadnoughts featured gun layouts that are considered "silly" and "horrible" by modern standards, with main-caliber turrets positioned to the sides of the superstructure, in the middle of the ship, behind other turrets, and generally having terrible firing arcs.

Estimated Volume: 25,000-50,000

Post-Dreadnought
Once the HMS Dreadnought set the standard of "sensible" gun layouts, almost all battleships designed after it would feature superfiring main turrets on the centerline of the ship, where they could fire both over each other and to both sides. Many late-WW2 designs also had a large amount of both light and heavy anti-air, with older ships being modified to have as many guns as weight would allow put in every open deck position to protect against the increasingly prevalent air threat.

Estimated Volume: 30,000-60,000

Super Battleship
The biggest guns on the biggest ship. With armor that can stand up to immense punishment and guns that can put a cruiser on the bottom in a single shot, super battleships are an immense investment that can take on anything smaller than itself without concern. If you really need an example, simply look at the IJN Yamato.

Estimated Volume: 40,000+

Fortress Ship

A huge ship with excessively high armor and firepower that usually moves incredibly slowly, and costs a small fortune.

These types of vessels serve a niche role and are rarely used for their high investment costs and lack of maneuverability. They are nevertheless unmatched in their ability to take on enemy fleets single handedly, and can be useful as a mobile frontline, supplying materials to nearby fleets.

Estimated Volume: 50,000+

Extra Notes

On Extraneous Weapons and Designs:
A ship using mainly non-projectile weapons such as lasers and PACs can be classified in much the same way as ones that use APS and CRAM, but some amount of discretion may be necessary to determine if these weapons should be considered high or low-caliber. For a more immersive classification, you may want to designate these as laser-cruisers or particle-battleships, for example.

As for airborne versions of these vessels, the same classifications can still apply, although some things such as destroyers, frigates, and torpedo boats may be fundamentally different thanks to their airborne nature. Again, for immersive classification these may be referenced as air-destroyers, air-dreadnoughts or float-cruisers, etc.

Closing

If there’s interest, I may update this guide to include air and/or weapon-specific classifications. Also, if there’s anything you think I missed or got wrong, feel free to let me know in the comments, I’ll try to keep this updated with any suggestions!

Todo:
Add pictures/examples

[nimbalo400]

Dommer Raisei had said "its a misconception through media that dreadnoughts are above battleships, seeing as how they (dreadnoughts) came first." implying that battleships came after dreadnoughts when they were just a form of one.

[inkyboi]

I don't think anyone was necessarily trying to say that a dreadnought wasn't a sort of battleship, just that how i'd delineated the two was inaccurate. However the factor of pre-dreadnoughts having more and/or larger secondary guns instead of focusing on main guns is accurate.

[nimbalo400]

So doomer is right but also wrong, the first battleship was made in the 1800s the dreadnought was a revolutionary redesign of battleships that, in contrast of older designs that had a more mixed caliber secondary armament, had a focus on the main guns. Later after ww1 however the idea of a fast battleship took hold in many navies and thats where you get ships like the Iowa.
TL;DR a dreadnought is a form of a battleship

[Rene12188]

I would love to see more content like this for air and weapon classifications

[inkyboi]

@flori1994
Noted and amended. I figure I leaned a bit too hard into the "submarines should be stealthy" approach, forgetting that this is in fact FtD we're talking about, not even mentioning real life.

[flori1994]

Not bad. But i have to note that the estimated volume of a submarine might be kinda low. As modern nuclear rea life submarine can easily reach and surpass the size of a cruiser (Belgorod, Typhoon (red October), ohio class)

[inkyboi]

Also, any continued dreadnought vs battleship discourse is going to be largely ignored as I've already indicated that my understanding was flawed and this will be amended in the future. (I have no ill will towards those that are trying to correct the misconceptions though, I fell for it after all.)
To make it abundantly clear: Battleships began as the ships with the biggest guns and heaviest armor, but frequently stuck turrets wherever they felt like it. Then the HMS Dreadnought came along with its all guns center layout and standardized this since it allowed optimal salvo weight on either side, and later battleships with this layout are considered dreadnoughts while still most commonly being called battleships.

[inkyboi]

Njordr:
It's hard to tell what this should be without details like top speed, specific armament, and armor scheme. Based on how the main guns appear I'll assume they are rapid firing mid-high caliber APS. The missiles in the rear appear to be mines as I don't see fins, and it has a limited AA compliment. As such, I'd initially lean towards a minelaying light cruiser or destroyer, although the gun caliber would (traditionally) be rather large for a destroyer.

[inkyboi]

Took me a bit to notice the comments, but while I continue to not have a rewrite done I might as well use my (limited) knowledge to help classify things lol.

Eternal Engineers Of Aegis:
I'd personally lean towards classifying that as a battlecruiser/fast battleship, or whatever else it's been called. The extremely heavy armament and high top speed with respectable but not overwhelming armor is pretty much textbook for a battlecruiser, but plenty of people say that they're no different from heavy cruisers anyway, so either one works.

[Eternal Engineers Of Aegis]

what if my Heavy cruiser costs 400k something mats and has 6 500mm guns but can top 45 m/s with a very solid yet not too thick armor belt and never sinks?