Wednesday, April 28, 2010

History Nerdiness Takes No Vacations, Part 3

At the tail-end of the Civil War there was talk in the United States of sending its fleet of monitors across the Atlantic Ocean to shell Britain while the huge Union Army invaded Canada to punish the Brits for supporting the Confederacy.  These things never happened.[1]  The Canada thing wouldn’t have been particularly popular.  And all the monitors would have sunk right around the first time they were hit by a reasonably sized wave.

So the United States decided to do the only sensible thing: they sold their most modern warship to the Japanese and settled down to live la vida isolationist.  The US Navy was basically limited to a few monitors, which were fit only for coastal defense, if that.[2]

At the tail-end of 1883 the Brazilian Navy took delivery of a British-built battleship called Riachuelo.  This ship, along with the Aquidaba, a smaller ironclad, made the Brazilian Navy the most powerful in the Americas.  The United States knew it had to respond.

Riachuelo and Aquidaba were turret ironclads from the awkward, experimental phase between the monitor-style turret ships and the finalized pre-dreadnought ships such as the British Majestics.  Oddly, the British Devastation, laid down in 1869 and launched in 1871, basically pre-figured the finest of the pre-dreadnoughts.  But it took a really long time for the idea to catch on.

The Brazilian ships, and the two American vessels designed to counter them, had an awkward arrangement of monitor-style turrets mounted en echelon amidships.  This design meant, in theory, that the full weight of fire could be brought to bear fore, aft, or broadside.  In reality it meant that the ship’s structure got in the way and the ships looked really stupid.[3]

Those first two American battleships were the USS Texas and the USS Maine.  The Texas served a relatively uninspired career.  The Maine, though, probably ended up as the most famous pre-dreadnought battleship, since there really aren’t any other battleships in the world that can claim that they started a war due to an accidental ammunition explosion compounded by yellow journalism.

By the time of the Maine’s unfortunate demise the ship had already been replaced by the first generation of true American battleships: the three ships of the Indiana-class pre-dreadnoughts.  These were relatively small, relatively short-ranged ships that would probably not have been able to stand up to the British Royal Sovereigns, much less the follow-on Majestics.  Still, they were more than enough to cow the decrepit Spanish navy.

That conflict also saw the first deployment of USS Iowa (BB-4, not BB-61…)[4], the first American ocean-going battleship.  Too late to join in the fun were the two ships of the Kearsarge-class,[5] however.

The American Navy was behind the rest of the world (y’know, except for Spain and, finally, Brazil) in terms of developing a blue-water fighting force.  But the war scares with Spain, the whole, “Holy crap, the Brazilians could kick our asses,” thing, the actual war with Spain, and the sudden possession of a Pacific Empire after the Spanish-American War[6] meant that the United States had to change.

The sleeping giant, to borrow a phrase from Admiral Yamamoto, had awakened.  Between 1893 and 1908 the United States commissioned 24 pre-dreadnought battleships.  This was the country that had previously managed to take more than two decades to build five monitors that were completely obsolete when they were laid down.[7]  Among them, the six Connecticut-class battleships were a match for any pre-dreadnought in the world and the five Virginia-class ships would probably have been if they hadn’t repeated the Kearsarge-class’s design folly of installing the secondary 8” guns on top of the main turret.

I choose 1908 because of a single event of great significance that occurred that year: the launch of the USS South Carolina, America’s first dreadnought.  The two South Carolinas were smaller and slower than the Dreadnought, owing to tonnage restrictions and the British adoption of the steam turbine engine.  The three following classes, the Delawares, Floridas, and Wyomings, sought to fix various shortcomings in the initial South Carolina design.  The Delawares jumped four thousand tons and two and a half knots top speed (Delaware herself also served as a test bed for the steam turbine, with North Dakota retaining the old triple-expansion system.  Both had the same performance characteristics, but Delaware had 30% greater endurance.  This figured heavily in to future planning, as the US was already looking at the need for a fleet capable of crossing the Pacific and engaging the Japanese).  The Floridas were an intermediate step, but the Wyomings added another seven thousand tons so they could mount a sixth double 12” turret and more armor.

This actually brings us to a point where we can look at battleship design philosophy.  There are many ways of mounting a gun on a ship.  The broadside was, of course, the original way, with bow and stern “chasers” to offer some tiny amount of fire fore or aft.  When you start mounting turrets, however, things change.  Weapons and superstructure get in the way.  That’s why the original Monitor was a single turret sticking up of a raft.  For any following monitors with multiple turrets the centerline mount remained, as stability was an issue.  But as ships got bigger and had more freeboard, stability became something less of an issue and other considerations came in to play.  As I mentioned with the original Texas and the Maine there was an amidships, offset arrangement.  When the pre-dreadnought designs were finalized they incorporated a fore and aft main turret with the secondary battery in so-called wing turrets (save the aforementioned Kearsarges and Virginias, which attempted to solve one set of problems by creating a bigger problem).

In order to understand why turret gunships had several different designs we need to understand the solutions they provided in light of the problems the designers faced.  In order to understand the problems we need to understand the geometry of the ship.  More importantly, we need to understand the geometry of the ship in the context of the larger geometry of the naval battle.

Imagine for a moment I’ve given you a job.  I’ve supplied you with ten cannon and told you to build a ship capable of sinking another ship.  So you take those ten cannon and put them all on one side of the ship and attempt to go after your opponent.  But he gets to the other side you and blows you out of the water.  So you try again.  This time you build a round ship and place guns all around it.

This time, though, you find that your ship is barely stable and hardly maneuverable.  Worse, although your opponent cannot approach you without being fired on, you cannot hit him with more than one or two guns at a time.  So you, again, lose.

This time, however, you’ve figured out what you need to do.  I, for some reason, am willing to give you a third shot and give you not ten, but twenty guns.  This time you put eight down each side, plus a couple in the front and rear, just in case.  Now, no matter how your opponent approaches you, you can turn your ship and bring a devastating blow to bear.  This time you win.  Congratulations, you’ve just invented the man of war.

Now, the strengths and limitations of the man of war are fairly obvious.  The ships can bring a lot of firepower to bear, but only if their sides are pointed at the target.  As long as wind was the primary form of propulsion, this made the ships exceptionally hard to deal with.  They turned slowly and took a long time both getting in to and out of range.  Moreover, the range of combat was limited ranges between “close” and “extremely close,” due to the fact that the sides of the ships are constantly moving up and down with wave motion.  The only way to get a hit is by matching the timing of the firing with the point where the deck is relatively level.  Fancy shooting it’s not.

The one obvious strength of such a battleship, though, is to the side.  The obvious weakness is the front and back.  There’s simply far less weight of fire that can be brought to bear.  Combatants, then, endlessly attempted to get their broadside against the other ships bow or stern in a maneuver known as “Crossing the T.”  Otherwise the two ships would simply batter each other until one side gave up.

The limitations of technology being what they are, eventually an equilibrium will be reached.  There will be differences in philosophy, but, generally, if all sides are equally capable of building ships the battle will come down to ingenuity, training, discipline, and who make the best use of what’s available.

Nowhere was this more obvious than the Battle of Trafalgar.  Nelson had 27 British ships to the 33 French and Spanish ships.  Among the Spanish ships were the two biggest First Rates in history.  Nelson even sacrificed the initial position by forming in to two battle lines that allowed the Combined Fleet to cross his T.  But Nelson knew his crews were better disciplined, his gunners better trained, and his ships in better shape than his opponents.  He also knew his unorthodox tactics would throw his opponents off.  And he knew that the Spanish and French didn’t get along and his counterpart didn’t really want a fight.  These are the insights that bring glory.

In learning to fight with battleships, though, the captain and admiral had to realize things had changed.  Go back to that perfectly round ship.  When it gets right down to it, by building a turret with two guns in the middle of your ship and removing all obstructions from the deck you have effectively built that round ship, but with the added benefit of better stability and maneuverability.  But there are limits to the number of guns you can put in a single turret, so you’re sacrificing weight of fire to get versatility.  Let’s say a situation arises where you need more firepower or the ability to engage multiple targets at once.  What do you do?

Add another turret.  There are three ways you can do this.  You can put the turrets next to each other, so you’ll get the full weight of fire to the fore and aft, but only half to the sides.  This makes the ship quite wide, though, and wider = more resistance in water = slower.  You can mount the two turrets in an offset pattern, so you can get a full-weight broadside and full fire to the front and back.  This combination, however, severely limits your ability to build a superstructure.  It also doesn’t really help with stability and the turret firing across the deck is limited in its ability to target.  Finally, you can line the turrets up on the centerline.  You’ll limit your firepower to the fore and aft, but be able to bring a full weight broadside.

In a steam powered warship this is the most overall desirable system.  Ships are most stable firing to the sides and without the need to worry about wind direction it’s much easier to change direction to keep the enemy under fire.  Crossing the T, meanwhile, remains an important tactic, as a force that’s already deployed in line of battle can fire broadside after broadside at an enemy formation that may well be infinitely larger and only have to face the forward guns of the first ship.  Togo took advantage of this at the Battle of the Yellow Sea and then again at Tsushima, where he defeated a force that had 8 battleships to his 4.[8]

With the finalized pre-dreadnoughts, the idealized arrangement then involved fore and aft main turrets, meaning that the ships could bring the full weight of their armament in to either broadside.  The secondary battery, then, was split in half and only capable of engaging one side or the other aside from the lead and trailing guns.

The question then becomes, though, what do you do when you want to move from a main/secondary arrangement to an all big gun arrangement?  You can’t plop an infinite number of turrets along the centerline, as the ship will eventually become too long.  Six turrets is, in fact, pretty much the maximum number.[9]  The armor belt gets too long and the turrets start restricting the firing arcs of the other turrets.

The first solution to this issue is the creation of the superfiring turret.  To superfire you basically create a terraced design, placing one turret behind and above another.  This allows you to stack guns and effectively double the weight of fire in to the same arc.  The other option is to incorporate wing turrets, which effectively replace the old secondary battery with an extra main battery turret on each side.

The British dreadnoughts incorporated a pair of superfiring turrets in the forward arc, while placing a single turret supported by two wing turrets in the rear of the vessel.  This meant that there were always two turrets that could fire in to the forward arc, while the wing turrets could add a third once the engagement got a little past end on.  The wing turrets could then similarly offer fire to the rear, while the rear turret, the two forward turrets, and one of the wing turrets could fire in to each broadside.  The Germans and, eventually, the French followed suit for most of their dreadnoughts.  Although the Germans did switch to a centerline battery for the Konigs and the Bayerns.

America, however, adopted a centerline battery with the South Carolinas.  The goal was to try to counter the weight of fire provided by Dreadnought with a smaller ship, so instead of wing turrets they were designed with two superfiring centerline turrets fore and two aft.  As such, the South Carolinas could offer the exact same weight of broadside as the Dreadnought with one less turret.  And, when it gets right down to it, the design didn’t really lose much in the non-broadside arcs, especially directly aft.  There is a reason that the wing turret was phased out.

This brings us to the next innovation in American battleship design.  The Wyomings represented the peak firepower possible in a two 12” gun turret design.  The extra length needed for the sixth turret meant far more weight in armor needed to be added to the ship, while the two central turrets were useless to both the front and rear.  So the next American design was shortened and a single turret was removed, but it still managed to increase firepower due to a single change, the switch to the 14” main gun.

Enter the two ships of the New York-class, BB-34 New York and BB-35 Texas.






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[1]Although I dream of one day building a time machine, going back to 1865, and convincing Andrew Johnson that Celine Dion and Alanis Morissette are a clear and present danger and need to be stopped at all costs…

[2]The US Navy did engage in a bit of sleight of hand, however.  In 1873 after a war scare with Spain it was decided to update five Civil War-era monitors.  The ships were in such bad shape that Secretary of the Navy George Robeson actually had the five ships scrapped and started building five new ones.  This maneuver was somewhat less than legal and ended up costing quite a bit of money, which the Hayes Administration decided it didn’t want to be a party to.  The five ships were eventually built, however, but they were launched between 1891 and 1896. Again, consider that it took five months to build HMS Dreadnought.

One of the monitors, USS Amphitrite, did serve through WWI, however, after getting refitted as a submarine tender.

[3]At least in my humble opinion.

[4]One of the biggest problems in discussing the evolution of American and British battleships is that they keep using the same names over and over and over again.  The US named all their battleships after states, save one notable exception.  The British apparently only had about a dozen ship names going forward from the Age of Sail to the end of World War II.  Therefore, there are about a hundred Revenges, and a hundred Royal Sovereigns.  There are also no less than nine Dreadnoughts, stretching from the 16th Century until the decommissioning of the nuclear sub with that name in 1980.  Among those were both the Dreadnought and an 1870s pre-dreadnought named Dreadnought.  Of course at the time of the construction of the pre-dreadnought Dreadnought no one knew the Dreadnought was actually a pre-dreadnought.  I think that might be one of my favorite sentences of all time, by the by…

[5]Kearsarge being the only non-state named US battleship.  She was named for the Civil War sloop that took down the CSS Alabama.  In an extremely interesting sidenote to that, at least if you’re me, the commanding officer of Kearsarge was one John Winslow.  The commander of CSS Alabama was Raphael Semmes.  The two had been cabin mates during the Mexican-American War.  Also, lest you think that Kearsarge didn’t get used too much, there were two different Essex-class carriers that received the name and the US currently has a Wasp-class amphibious carrier in active service with the name.  One of the Essexes was re-named Hornet before commissioning, however.  In honor of, well, CV-8 Hornet.  Of which there have been eight.  Also the F/A-18 Hornet is the primary Navy warplane…

[6]You know, they got the Philippines and Guam.  But there weren’t any battleships involved.

[7]Meanwhile, between 1908 and the end of the Great War the United States built no less than 15 dreadnoughts.

[8]Scheer, the German commander at Jutland, tried to Cross the T against the British.  Admiral Jellicoe, the British commander, was able to very smartly counter it.  We’ll explore that later, though.  Like Nelson at Trafalgar, Jellicoe knew how to look for the small advantages and make use of the better disciplined British Navy.  Really, it was the discipline and intelligence of the RN that made all the difference.

[9]To the best of my knowledge, only four ships ever had six turrets in line: the two Wyomings and the two Japanese Fuso-class battleships.

[10]Of course the French barely got involved in the arms race in the first place.

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