Cruisers are medium-large warships that have the firepower of a small battleship but the speed and armor of a large destroyer. These ships typically have a high degree of firepower and disproportionately high speed and maneuverability at the expense of armor. There are four classes of cruisers: Light Cruiser, Heavy Cruiser, Battlecruisers, and Guided Missile Cruisers. Light cruisers tend to be scaled up destroyers, mounting bigger guns and slightly better armor and torpedoes. Light and heavy cruisers should both be built with the ability to fight off everything in mind. Light cruisers focus more on fighting destroyers. Heavy cruisers are better for supporting battleships and engaging other cruisers, along with having a very good AA armament. Battlecruisers are not necessarily a well-defined class. The simple definition is: Take a speedy cruiser hull and put big battleship guns on it. Lastly, guided missile cruisers tend to have guns on one side, and a missile launcher pad. However, despite all their differences, cruiser should all be designed with the ability to engage all foes, have a reckonable AA armament, and be fast.
Light cruisers typically have small guns like destroyers, for example the Mk. 45 5 Inch gun. They may also carry The 30.5cm gun family. Heavy cruisers typically carry the 4x5x2 gun family, aside from the 38cm guns and above. Battlecruiser will have the 38cm and larger guns. Guided missile cruisers are more modernly armed, with the Mk. 45 5 Inch gun, Phalanx CIWS, and VLS. All will have batteries of lighter weapons such as the 30.5cm Gun family. One or two Mk45 5 inch guns are carried for use against fast boats or similar vessels. Anti-aircraft weapons will be carried in quantity, as they make great Aircraft Carrier killers, as well as ASW weaponry. Cruisers are the general kill everything ship, being useful in many, if not all situations.
These are the two main types of cruiser, characterized by their armament and protection.
This is the raiding cruiser whose speed, firepower and maneuverability enable it to keep up with destroyers and fast boats and circle larger warships. They are faster and more maneuverable than heavy cruisers. They are about the size of a large destroyer, though with much heavier armaments. Some so-called destroyers may fall into this category.
This is the general-purpose cruiser which can deal with battleships and carriers alike. With the guns equivalent to battleship secondaries, or in the example, the same guns on a battleship, they use long-distance battles and flanking to bring down heavier warships. Their speed usually is slower than a light cruiser, but is better than a battleship. These are ideal carrier-killing surface ships, since its size enables it to carry large batteries of AAA and enough anti-ship weapons to sink it many times over. Ironically, the hull of a heavy cruiser is adept to conversion into a carrier - anything smaller than a cruiser is simply too small to be effective and anything much bigger would be too vulnerable without rare metal. The existing armor would greatly bolster the durability of the ship.
Roles and Usage
Cruisers will typically be utilized for long-range patrol and are an ideal warship against an aircraft carrier, given its economy and effectiveness. Cruisers have the firepower to deal with the lighter-armed carrier while possessing the size to take in the damage and mount necessary AAA to bring down the carrier air arm. They are decent against lighter vessels and if taken in the best of all circumstances, deal with a battleship. However, the superior protection of a battleship may outlast the cruiser.
See Battle Tactics
As these vessels are middle-ground between battleships and destroyers, tactics will vary. When fighting destroyers, treat it like a battleship. When fighting battleships, treat it like a destroyer. The same goes for the opponents. Rely on flanking to bring the big guns to bear on weak points.
New antiaircraft weaponry such as the Phalanx bolster this vessel's defense against aircraft, making its job as aircraft carrier hunter easier. Long-range weaponry like the VLS that came in can further menace carriers with ease. Overall, these are powerful weapons in the right hands, and whose future is tied to that of the battleship.