Educate me on naval warships and fleet formation

There’s something I don’t fully get (and have no idea where to look up myself) is why do we need so many classes of ships, and what are their roles? Why do battleships need destroyers, cruisers and frigates? Is it more practical to build several smaller ships than one massive ship that can do everything those smaller ships could?

Or why can’t we just build one massive ship and use drones (manned or otherwise) for everything else?

Just my initial thoughts: We have big ass ships located all around the world so we have bases to take off and land on increasing the scale of our efforts. One big boat would just be one big target and would not give us any advantage of being close to a certain location, and having a bunch of small ships aren’t as effective as having a bunch of planes and rockets since we aren’t typically fighting naval battles but instead bombing people from the sky.

You will get lots of learned answers I’m sure. But here is my take on it.

Ships have had different roles for a long part of naval history. Right back to ships of the line.

One critical thing is that in the past in confrontations a bigger ship can take on an amarda of smaller ships and take every single one out without suffering any damage. This was the day of the battleship. The ship with 10 inch guns facing one with 12 inch guns would find itself in range of the bigger guns before its guns could reach the enemy. Thus the arms race for bigger and bigger guns an ships capable of managing them. Of course the guided missile pretty much brought that game to an end. But for half a century plus that was the equation.

The terminology for ships has arisen over time and still roughly matches their role. A frigate is primarily a defensive ship. Its role is to protect other ships - including merchant vessels. So its ability and fit out will reflect the need to detect and neutralise enemy threats. A modern frigate will need to worry about submarines, naval vessels and aircraft, not to mention missile threats from potentially all of these. Expect lots of defensive weapons, decoys, lots of ability to detect and track threats. But not so much on the heavy hitting armaments. A destroyer on the other hand is intended to actively go out find and destroy threats. Its fit out and armament will tend to reflect that. There will be overlap.
Littoral ships are designed for coastal work, they tend to be smaller, more agile, more general purpose. The ability to move and land large numbers of troops is another role. Carry say a thousand troops and the landing craft to deploy them in an hour. That is a big capability.
Aircraft carriers are all about force projection. With a small air force aboard they can engage in conflict half a planet away. And not just on the sea. But they are vulnerable, and insanely valuable assets. So they get a small navy of their own to tend and protect them.
Then you get the support vessels, oilers, supply ships etc. Little armament beyond enough to fend off casual engagement, but still fitted with sensors and other capabilities to allow them to work in a fleet. Then you get interesting hybrid ships, mini aircraft carriers, ships that carry a significant fleet of helicopters only. Expect drones deployed from ships to be the next big thing, bringing about another change to the balance, especially the ability to project force.

Submarines come in different flavours. Nuclear missile submarines have a major strategic role in keeping the nuclear peace. Their job is to vanish into the oceans and never be seen by your enemy. Its main armament is never intended to be used. An attack submarine is intended to go hunting ships. It needs to be dead quiet, fast, and armed.

A clear thing that is occurring is that the peacetime role for naval vessels is becoming more apparent. Ships that have the ability to carry troops can be invaluable in times of natural disaster. Your 1000 troop carrying ship can house 1000 homeless victims of a tropical cylone that wipes out a community, and it will have the medical facilities to cope as well.

I’m over sixty and the debate over the value of certain types of ships and their worth has been going on since I was a child. And before that too. I’ll throw out some pros and cons:

Aircraft Carriers: Multi-billion dollar aircraft platform that MAYBE(?) knocked out by a few missiles neutralizing it and all the expensive aircraft and munitions aboard. Is it worth it? Debate has been hot on that for years.

Battleships: Delivers a massive accurate super-deadly long range artillery fire on the enemy. Sure, but same as aircraft carrier can be neutralized by a few missiles. And can only hit enemies near the oceans you control. Can our missiles and drones do same thing better? You bet. We stopped keeping these a good number of years ago.

Cruisers: Smaller version of battleship. The guns don’t get used much. Now our newer ones launch guided missiles and maybe drones. Are they a good value compared to our long range drones and missiles? Not so sure on that.

Destroyers and Frigates: Relatively small and fast ships that can get solid firepower anyplace there are oceans. These can do a lot of jobs and are still valuable.

Submarines: Depend on stealth. I’ve been thinking on starting a thread asking can they really be stealthy in this modern hi-tech age? I don’t know and I think that is a key question. They are very powerful.

Can we build a massive ship and not need a bunch of ships? I’ll answer that question with a question. Can we keep that massive trillion dollar ship from being knocked out by (???) type of attack at the start of a war and lose it all in a day? I don’t know if anything like that can be protected from modern missiles and drones and other types of attacks like maybe an EMP.


Question that needs to be answered is who is our opponents going to be? Make your best guess. When you are fighting ISIS, terrorists, and small nations like Libya or Argentina do you really need all these expensive to purchase and maintain ships? Or do you expect to fight a major nation like China or Russia or some coalition like NATO or the Warsaw Pact, someone who might field an arsenal of their own guided missiles and drones? Closest thing I can remember to a real naval conflict since WWII was the Falklands War and back then the large ships were effective but warfare technology has changes tons since then.

Can’t say more gotta run to work.

I’ve read the following; is it correct? An aircraft carrier “needs” destroyers and other ships to protect it from submarines and other attackers. BUT, the carrier is faster than other ships so, in time of urgent crisis, is sent ALONE across the ocean to prepare for battle. This may be cause for some concern since destruction of an unprotected $13 billion carrier would be displeasing. (Or is the lack of protecting ships irrelevant since our top enemies have a way to kill our carriers even when protected?)
I’ve exchanged e-mails with a math professor about interesting Rock-Paper-Scissors variants. He has a navy example, which I will not show here because I’m not sure if it’s true-to-life or contrived. (Are destroyers faster than cruisers?)

I’m not a naval strategy expert, but I don’t think so. The aircraft carrier may be on its own if it needs to launch and recover aircraft in an emergency, but wouldn’t travel huge distances without the fleet. In dire emergency it is possible to do so, but I would guess it’s pretty unlikely.

To return to OP: The very definite answer is that all of these ships are needed. The idea of putting all your eggs in one basket is foolish. We invest huge amounts of money in our carriers because nobody has yet conceived of a better way to move an airport, and they are valuable assets that must be protected. We also have any number of more minor tasks that do not require such a large ship. Recall that the bigger you make something, the greater it’s maintenace and supply requirements. So if every ship was a giant multirole behemoth, you would have a hard time finding resupply and maintenance at smaller ports. The current assessment - based on the Falklands and Iranian naval exercises - is that individual ships can be overwhelmed by large numbers of small opponents. Therefore, it is likely better to use a variety of ships acting in concert.

Historically, every time someone has tried to invest all of the resources in a small number of mega-ships, it has not worked out so well. Just off the top of my head…

  1. During the Napoleonic Wars, most action was done by frigates and brigs. The top-rated ships with dozens and dozens of guns were big, slow, valuable, and supply-hungry. They tended to stay in port because (a) they were too slow and expensive for any other duty and (b) they were such an investment that nobody wanted to risk losing them. So they mostly sat around and waited until the leaders were ready to commit to a really big battle.

  2. In 1906 a new class of gigantic battleship called the “Dreadnought” was introduced. It was intended to be the most formidable ship of all, and it accomplished practically nothing. Mostly, the Dreadnought fleets just stared at each other because nobody wanted to risk their valuable ships unless they were certain of victory. The only major battle between Dreadnoughts happened in 1916, at the Battle of Jutland. WW1 also saw several large vessels sunk due to asymmetric threats such as submarines and naval divers. This just reinforced how fragile the ships were.

  3. In WW2, Germany’s Dreadnought Bismarck accomplished practically nothing. She conducted only one operation before being sunk by the British. Her sister ship, the Tirpitz, hung out in port in Norway. Her presence was threatening, but she actually accomplished nothing and was sunk in 1944.

  4. The Japanese battleship Yamato was the heaviest and most powerfully armed battleship ever constructed. She fired her guns exactly once, in the Philippines. At the end of the war, the Japanese wanted to deliberately beach her on Okinawa so that she could be turned into a sort of permanent pillbox, but she was sunk before this could happen. Her sister ship, the Musashi, made several sorties and transported supplies, but I am not aware of her ever actually engaging in surface warfare. Musashi was sunk in 1944.

Another point: in the past, the bigger the ship, the bigger its guns. Now, though, corvettes, frigates, destroyers and cruisers all carry basically the same missiles. This hugely changes the balance of power, and discourages navies from investing too much in large ships due to diminishing returns.

Well, no. A bigger ship can carry more and better sensors, more weapons and also for frigates and destroyers, they can carry bigger and more capable A/C.

You are right of course. Modern day small ships can in theory sink large capital ships. Unlike earlier. But then some would say it’s been the case since the Torpedo* was introduced. And ship dimensions have only grown larger since.

*I mean modern torpedos, not the one Farragaut said “damn” to.

So it will seem that the armaments of a ship defines its role and capacity, will I be right to assume that?

Am I also right to say that there is a point of diminishing return in terms of cost effectiveness as ship size gets larger? There is the point about maintenance, resupplying, speed and I assume fuel cost.

How correct am I say, in summary, that Battleships went out of fashion because a group of smaller ships are much effective than one large ship?

ISTM that in the WW2 era it was indeed more practical to build several smaller ships since you can build and staff several destroyers for the price of one battleship and the destroyers will usually be more than a match for the battleship. That said, for shore bombardment the battleship was still useful. I think slow battleships - battleships that couldn’t keep up with the rest of the fleet - were indeed pretty useless.

I’m not sure if there was a place for cruisers versus destroyers or if the surface fleet should have ideally been a lot of destroyers and merchant escorts and carriers with a smattering of battleships or if a few fast cruisers would have been useful as well.

Not really. Usually it is the size and shape of the hull. Also, some ships are specifically designed for things like transporting amphibious forces or launching aircraft. Things like missiles and guns can be swapped.

Back in the day, there was a direct correlation between the size of the ship, the number of guns, and the necessary crew to man those guns.

I would think so, yes. I don’t know much about naval logistics so someone might have a better answer than me, but the size and diversity of the fleet should depend on the missions and the resources available. The US has global security commitments and a mammoth budget, so we get a lot of use out of our carrier groups. There is a persistent problem in that even our enormous navy is too small and spread too thin for the missions we perform.

At the same time, check out Russia. They have one aircraft carrier that is generally regarded as having poor maintenance. But they also have no real reason to employ it. Russia doesn’t have global expeditionary missions like the US does, and the Syrian War is the first time it has been used in years. It would be fair to say that their investment in big ships probably isn’t worth the expense.

I don’t know if there is ever an “upper limit” beyond which our ships should never be built. It appears that the current aircraft carriers do the job well enough. Do we really need a 500-meter giganto-carrier* that can land 747s? Probably not.

*Not a real thing.

Pretty much. What really doomed the Battleship was the rise of missiles. The point of a battleship was to carry really big guns. As missiles became better and more precise, we stopped needing those guns. They just became obsolete. Missile-carrying destroyers and aircraft can do the same job. Any time you can do the same job with a smaller ship, it makes sense to buy the smaller one.

You’ll need to define “smaller” and “large”. 50 000 ton battleships aren’t coming back. Battleships of any tonnage aren’t coming back. Alessan, with characteristic Israeli humility, didn’t mention the fact that the Israelis were at the forefront of a revolution in naval technology and tactics during the 6-day war; The Israelis and Egyptians virtually reenacted the story of David and Goliath when a 67-ton ship crippled a 1700-ton ship which was later easily sunk: HMS Zealous (R39) - Wikipedia

So, yeah, battleships are not coming back. Aircraft, smaller ships with missiles and shore launchers will prevent that. You’re not going to see 50 000 ships with a dozen 16’ guns.

But destroyers today are heavier than destroyers of the past. Carriers are getting heavier than those of the past. The general tendency is for the weight of a ship type to go up.

If you want a blue water ship, you need to be big enough to be stable on the ocean. But if you’re interested in coastal waters, you may want to go small since you’ll be less likely to get stuck.

You also want as much size, weight and power capacity as you need for your particular role(s). If you’re big enough, you can get hangars for helicopters which are like very small, very fast ships that can change their height. That’s handy. If you go bigger than that, you might get small, likely rocket-launched, fixed-wing UAVs. Bigger still and you get mid-sized aircraft like the E-2 or the F-18.

With the advent of networked warfare, it might be that more, smaller ships will become common. Or fewer bigger ships that act as motherships for sea/air manned and unmanned platforms might become prevalent. Or maybe having a huge radar array will become importantl and we’ll end up with ships that are the equivalent of an E-3. We don’t know yet and can at best provide educated guesses. My guess is that the breakdown will largely be: aircraft as spotters and light kinetic work, 10 000 ton ships as shooters and motherships, small unmanned ships for coastal work and decoying/jamming.

No. Battleships went out of fashion when Billy Mitchell showed they could be sunk by aircraft, and pretty rickity aircraft at that. Then the Japanese sank the Repulse and Prince of Wales and that was it for the battleship as a main fleet weapon.But they are still very useful, even today. Nothing better for parking enormous firepower off an enemy beach.

Unless you are fighting a more sophisticated foe (and we aren’t likely to be) modern battleships and carriers are pretty much invulnerable. It would take waves of ship-killers like Exocets to take out the USS Carl Vinson, for example. The only easy way to kill a carrier is with modern torpedoes or nukes. Neither of which is likely to be had by our adversaries.

Another factor is the increasing difficulty that all the naval powers except the Chinese have of manning all those ships.

The newer ships like HMS Elizabeth only have a crew of 679 sailors, compared to the Nimitz Class carriers which need six times as many.

On the drone issue, the reason is that if you build a drone with capabilities close to modern fighters then it’s going to basically cost what a modern fighter does. The only up side to that is that risking one merely risks the price of the plane and loss of combat capability to the task force instead of a life, but the trade off isn’t there to do this as yet. We can and do make vertically specialized drones that also have some other capabilities…such as recon drones that are also armed. But in all cases the drones aren’t anything close to as capable as a manned aircraft.

As to why we can’t just build one ship to rule them all, you basically can’t build one ship that does everything. And you wouldn’t want to if you could, because all an enemy would have to do is throw everything at that one ship…take it out and battle is over. Instead, you have ships that are very specialized. You can have ships operating in squadrons or even independently…we do that all the time (see examples in our freedom of navigation exercises in the South China Sea). But for a fight you need a fleet…a task group or carrier group or battle group. In that group in modern times you’ll have a screen of destroyers of various kinds…that gives you screening capabilities for ASW (anti-submarine warfare), air defense and an outer defense envelop for missile defense. Then you’ll have an inner defense screen for the larger surface ships. You also might have a screen of fast attack subs as well. Then you have the carrier itself with it’s CAP and air screen, that often includes ASW assets as well. It’s all designed to do different things and focus on different threats or different attack capabilities. We have missile ships for launching surface to air, surface to surface and cruise missile capabilities. You have ships designed to hunt and prosecute submarine threats. Most of the ships also have some cross over capabilities as well, so they can do surface to air AND close final protection if it comes to that.

No mention of the death star? Come on man…

W/regard to the demise of battleships, it’s interesting to note that both the U. S. and Japan realized this at almost the same moment. Early in WW2, April and June of 1942 to be exact, the U. S. And Japan met in the Coral Sea and at Midway. These were the first naval battles during which the opposing ships never came within sight of each other. All the combat was via aircraft. This doomed the battleship. As effective as they were, their influence was limited by the range of their largest guns, 20 miles or so.

Following these battles the U. S. stopped construction of a new class of battleships (Montana Class). What was going to be a new BB was transformed into a new CV, the USS Midway. At the same time the Japanese began work to transform what was going to be a BB “sister ship” to the Yamato and the Musashi. Destined to be the carrier Shinano, it was sunk 11 days after it was commissioned by a U. S. submarine, never to participate in combat.

Back to the Midway, there were 3 Midway Class ships, the Midway, the Coral Sea and the Franklin Roosevelt. The Midway, however, is unique in that it’s built on a BB hull.

Yes, they can. One worry about aircraft carriers’ vulnerability is that during the last 15 years or so they have been repeatedly “sunk” during wargames by a lone attack submarine infiltrating their fleet. If modern subs can go through what is probably the densest ensemble of detection devices undetected, they have to be incredibly stealthy.

Most ship types are historical, and date from the Age of Sail, if not before.

Ships back in those days were rated by the number of guns they carried - a first-rate carried upwards of 100 guns, a second-rate 99-98 guns, a third rate between 64-80 guns, and fourth-rates 46-60 guns. These were all considered suitable for serving in the line-of-battle, meaning that in those days (and up through 1942 really) the tactics revolved around sailing in line-astern formation (basically single-file), and shooting at each other, and/or trying to get across the enemy formation’s bow or stern (crossing the “T”).

So first through fourth rate ships were called “line-of-battle ships”, which got contracted to “battleships”. The vast, vast majority of these were the 74 gun third rates.

Meanwhile, fifth rate ships (40 guns early, 30-32 later) were used as scouts or for independent action- as “cruisers”, meaning that they were fast enough to evade bigger ships and strong enough to run down smaller ones. These ships were typically called “frigates”.

Sixth rates were typically from 20-30 guns, and were typically used for blockade duty, convoy escorts and dispatch carrying, as they were fast and lightly armed.

Even smaller ships were used- typically sloops of war, which were classified as having up to 18 guns, but weren’t “rated”, meaning that their commanders weren’t proper captains, but merely masters & commanders. The French term was corvette for these small ships

So you basically had battleships, frigates, sixth rates and sloops of war/corvettes in terms of ship types, all of which were well-defined in terms of how many guns they carried- a 74 gun ship was a 3rd rate, and was a ship of the line. (incidentally, the US frigates that included “Constitution” were 44 gun frigates, but actually carried upwards of 50 guns- more like a fourth rate)

Eventually with the advent of steam and breech loading guns, the number of guns ceased to be a relevant indicator of a ship’s capability, so they were categorized by what they did, rather than by the number of guns- battleship, cruiser, and corvette were the main categories at first.

With the advent of reliable torpedoes, motorized torpedo boats became popular, and a type of ship was developed to deal with them - the “torpedo boat destroyer”, which got shortened to today’s “destroyer”.

In WWII, the Royal Navy brought back the term “frigate” to describe smaller ships than destroyers, but larger than corvettes, that were used for anti submarine work and convoy escort- what the US Navy called “Destroyer Escorts” at the time.

So with that in mind, during WWII we had the four main categories of ships - battleships, cruisers, destroyers and frigates/destroyer escorts and corvettes.

Aircraft carriers were added as their own type not too long before World War II. Once this happened, battleships were functionally obsolete. The last major surface actions were off the Phillipines between the US and Japan in 1944. Battleships were too vulnerable to air attack, and too short-ranged to remain useful- battles were fought at airplane range, not at gun range for the most part. Missiles only extended that range.

So after the war with the advent of missiles it got murky; ships are mostly distinguished by their roles again- cruisers (Ticonderoga class) are primarily for air-defence, frigates were typically for anti-submarine warfare, and destroyers were all-around ships. Nowadays, it’s mostly cruisers and destroyers, with little functional difference between the two- the Ticonderoga cruisers were actually built on Spruance class destroyer hulls and displace roughly the same tonnage as Arleigh Burke class destroyers (which is very similar to early WWII heavy cruisers!)

In a sense the OP’s got it right- the US Navy(not including support ships) is composed of destroyers (68), cruisers (22) and aircraft carriers (11), with the cruisers performing a specialized air defense role for carrier battle groups, and destroyers doing most everything else.