Battleship, cruiser and destroyer ; what is the difference?

Battleships signified capital ships.

In the pre-dreadnought era, battleships were rather small (7,500 tons to 10,000) tons with a mixed armament of large calibre guns (it varied according to the era) from 10" to 12" guns. Some earlier ships had 18" guns but these were muzzle loaders that required their guns to b e depressed for loading the powder and the the shell. In addition to the main armament, there was a secondary armament which varied in numbers. These could be 8" down to 6" or so, depending on the nation and the era. Finally, there were tertiary guns (like 6 pdr QFR) for defense against smallere vessels.

There had been papers from the Italians who proposed an all big gun battleships. This theory was verified by the Japanese experience in the Russo-Japanese war of 1905. It was hard to distinguish betweene the shell splashes of teh medium and heavier guns. At about that time, the British adopted an all big gun, turbine geared ship that was both better armed, armored and faster than the pre-dreadnoughts (generally 18kts). The HMS Dreadnought had 10 12" guns in five turrets, could do an amazing 21 kts and rendered all previous battleships oboslete. The Americans actually launched the first ships (South Carolina class) with 8 12" guns in the A-B-C-D configuration but were slower to complete them. Additionally they were only 18kts.

Soon all major naval powers followed suit and buit all big gun ships. However, while the secondary armament was deleted, the smaller lighter caliber guns (6" or smaller) were retained for defense against smaller craft (needed because they were faster and a higher rate of fire was required for defense). Most of these ships had 12'" guns with the Germans having the superior 11" (more accurate) guns. Eventually as WW I progressed the desire for firepower spurned the development of larger guns and 14"guns were adopted by the Royal Naval which later superceded it with the 15" guns found on the Queen Elisabeth and Royal Sovreign class battleships. Similarly the German Imperial Navy adopted the 15" guns in the Baden class battleships. These later bigger guns ships were called super dreadnoughts. In America the 12" gun of the South Carolina and later Arkansas classes were replaced with the 14" guns first introduced on the New Yoirk and Texas. !4" guns remained the mainstay of the USN until the 16" was adopted with the last three battleships constructed (West Virginia, Colorado, Maryland).

WW I Admiral Jackie Fisher conceived of a fast cruiser armed with battleship caliber guns. He thought these would make excellent raiders in the Baltic Seae and thus the battlecruiser was born. Faster than a battleship (26 - 30 kts), they were armed with 12" guns like a battleship. The tradeoff was they were lightly armored. The Germans built their own too but armored them very well (as seen at the Battle of Skagerrat/Jutland) where British battlecruisers blew up and German battlecruisers took a lot of punishment (with most still getting home).

Cruisers were smaller ships design for scouting for the battlefleet and for trade protection. They were faster, carried lighter armor and had longer range than the battleships. The size of the cruiser varied on time and navy. Early cruisers were small affairs which were about 2k tons and armed with 4.1 in (105 mm) guns). Larger cruisres had 5-6" guns. Standards change and by WW 2, it was decided to classify cruisers by their gun calibers and not their size. Cruisers armed with 6" guns were light cruisers and those with 8" were heavy cruisers. Before the dreadnought the "armored" or "protect cruisers" were built by most navies. They had medium caliber guns (8-9.2" guns), could do about 18-21 knots and some protection. However, the advent of the battlecruisers made that entire genre of ship obosolte. Still they saw some serivce in WW I. Cruisers in WW II became more specialized. For example, both the USN, IJN and RN had cruisers built or converted into AA defense ships. For a while the IJN also had torpedo cruisers (most of the armament was torpedo tubes).

The Germans in the antebellum years were under the restrictions of the Versailles Treaty. They could only replace their pre-dreadnought ships with a ship under 10k tons and armament no bigger than 11". It was figured that the Germans would use that tonnage to build either a 8" cruiser or a coastal defense battleship (slow, 12" guns or so). The Germans did neither. Instead they designed a cruiser sized ship armed with WW I caliber 11" guns (of course, new 11" guns which were longer ranged than the WW I counterparts). Dubbed by the British pocket battleships, they were known to the Germans as Panzerschiffs (armored ships) better armed than any cruisere and faster than most battleships. Hencee their motto, Faster than Stronger, Stornger than Faster. The only ships they need fear were the British battlecruiers (and the French ones). When WW II broke out the Kriegsmarine reclassed them as heavy cruisers. The Graf Spee was the most famous of the trio (Admiral Scheeer and Lutzow/formerly Deustchland).

Destroyers were small ships that often served as scouts or screeners for the fleet. They were dubbed destroyers because their mission was to destroy the fear torpedo boat. I'm not talking about McHale's Navy size PT boats but small, bast ships armed with torpeodo tubes (some of them were a little larger than the WW I destroyer). Torpedo boats were thought to be able to evade the defensive fire of the battleship and with a cheap well placed torpedo could sink a battleship. To protect the battleships destoyers were created. They were larger, carried torpedoes and more guns than a torpedo boat. Starting in WW I destroyers were just a bit larger than a torpedo boat but by WW 2 some destroyers weere larger than early WW I cruiser!

In the day of sail, frigates were supposed to be escort ships and scout ships. In the modern era they were escort ships armed with smaller guns than a destroyer and meant to protect convoys from wolf-packs. Corvettes were even smaller and could be built cheaply but were very useful for convoy escort work. Neither of these ships were armed with torpedo tubes.

 

As you further look into it there are even more sub categories you will come up on.

Battleships:
Pre Dreadnoughts Late 19th-early 20th century battleships
Coastal Battleships shallow draft ships with heavy gun but cruiser sized
Monitors slow moving, shallow draft ships with one heavy gun turret
Hybrid Battleships Front half Battleship, back half Aircraft Carrier

Cruisers:
Air Defense Cruiser a light cruiser with many Destroyer sized guns
Scout Cruiser a heavy or light equipped with many float planes
Axillary Cruiser usually a passenger ship with lots of Destroyer/Cruiser guns and no armor
Q ships disguised merchant ship with Destroyer/Cruiser size guns

Destroyers:
Fast attack Transports old destroyers used to carry troops/cargo
DDM's destroyer configured to sweep mines

 

SniperSquad - suggest you go to the library and check out Jane's Fighting Ships or better yet, Conway Warships of the World 1920-1945, Warships of the World 1865-1898 and Warships of the World 1899-1919. I might have the years wrong but they've plenty of information on ships. If you're really interested, you might want to look into the International Naval Research Organization. Lotsa big name (authors/researchers) belong to it.

 

Sloop, corvette, and frigate all originated in the days of sail. They were similar in design and function, varying mainly in size, with frigates the largest. They often patrolled the seas independently or in small groups and when doing so were referred to as "cruisers", but that denoted the mission rather than a specific ship type. If you read something like "Lord Nelson awaited word from his cruisers" it refers to frigates sent in search of the enemy.

In the 1800s sloops, corvettes, and frigates came to have steam engines, modern guns, and iron or steel hulls, but the basic design remained similar to their wooden predecessors. In time corvettes and frigates were replaced by ships which dispensed with sail, and these came to be referred to simply as cruisers. Navies continues to operate small numbers of sloops - the Royal Navy was still building them in the early 1900s - mainly for patrolling the far reaches of empire where both coal supplies and modern opponents were few and far between.

By WWI the RN still had a dozen or so sloops, although they had had their sailing rigs removed by then. The war created a need for warships smaller than destroyers for a variety of duties including moving supplies and personnel, minesweeping, and antisubmarine work. The new ships were similar in size and characteristics to sloops, although they had never had sails, so the name was retained and large numbers were built - many of the "Flower" class, named for flowers, although it seems rather unmilitary.

Sloops continued to be built between the wars, becoming progressively larger and more sophisticated, with heavier armament, turbine engines, and other warship-like features, no longer the cheap ships which could be built in numbers in commercial shipyards. So the RN developed a new "economy" escort and resurrected the sail-era name corvette for something similar to the WWI sloop. Incidentally the first corvettes were also the Flower class. Before long there once again came to be a need for a larger, improved version, originally termed "twin-screw corvette" but soon called frigates. The British WWII frigate was similar to the US Navy destroyer escort (DE).

Postwar the term "sloop" died out, but frigate and corvette were retained by many navies. A rough rule of thumb is that corvettes are mainly for coastal waters or seas like the Baltic or Mediterranean, while frigates are larger and operate on the open ocean.

The USN (and a few of our allies like Japan) retained DE (DEG for ships with surface-to-air missiles) for what most navies were calling frigates until 1975; then we changed them to FF/FFG. A common myth is that FF stood for "Fast Frigate" although they were not notably faster than their contemporaries. The simple truth is that our type designations are always at least two letters, like BB for battleship or DD for destroyer.

Speaking of the USN, from the 1950s through 1975 we used "frigate" for a type of large destroyer, which we designated DL/DLG ("destroyer leader"). In the 1975 rationalization these became DDGs or CGs (guided-missile cruisers). Part of the rationale for this may have been that the Russians were building ships about the same size which Western media called cruisers. The Russians called most of them BPKs ("large antisubmarine ship") but it gave the impression that they had more cruisers than we did!

 

Wow! I am impressed by the number of ships that were there at the moment.

Was Pearl Harbour the biggest U.S. navy port during world war 2? What about the east coast? Were there lots of ships there too?

 

The Pacfic Fleet not at Pearl Harbor
US Pacific Fleet NOT at Pearl Harbor

The Atlantic Fleet on October 1, 1941, but not there locations.
US Fleet - Atlantic Fleet, October 1, 1941

 

M33 monitor. 10 knots max speed.

 

I wonder if any Soviet monitors with T-34/76 turrets have been presereved.
I know as late as the Cold War the Soviets made monitors with T-55 turrets too.

 

A little more on cruisers: The task of the cruiser was just about anything that wasn't being handled by small escort ships, destroyers, battleships and later, carriers. Some specific tasks were:

1. "Show the flag". These were often gunboat-sized ships used to keep colonies pacified.

2. scouting

3. Denying the enemy the ability to scout. (Sinking the enemy's scouts.)

4. commerce raiding

5. Intercepting and destroying the enemy's commerce raiders.

6. Defending the fleet against enemy destroyers and cruisers.

7. AA defense. Both as light AA cruisers and heavy cruisers packed with AA guns.

8. Participate in big unit battles, adding their gunfire into the mix. These are heavy cruisers and super heavy cruisers such as the Alaska's.

There's probably more, but I've hit the main ones.

The German Deutchlands were designed specifically for commerce raiding. Their K-class light cruisers were designed for both raiding and scouting by having a mix of both turbine and diesel engines.

Since no one ship could do all these things there was a lot of debate in most navies about getting cruisers that would do more than one thing. Great debates were ongoing about the the right mix of firepower, protection, range, speed, etc. More of one attribute meant that other attributes were going to suffer. Of course the interwar naval treaties really made the planner's and engineer's job fun!