Warship designation?

Modeling Subjects Ships
1

With all of this “Heavy Cruiser” discussion, I got to thinking—what do all of the nomenclatures really mean, specifically, in calling a ship a certain class? What makes a light cruiser, “light”, for example? What makes a ship a dreadnaught or battlescruisr instead of a battleship?

In WW2 there were light cruisers, crusiers, heavy cruisers—even AA cruisers! Then there were “battle” cruisers…??? Of course, it doesn’t get any less complicated with other classes…you have “pocket” battleships vs battleships, and then “fast” battleships???

And today, there seems to be only two types of US surface warships (maybe three): destroyers, frigates (I thought frigates went out in the War orf 1812!?!) and carriers…[%-)]

2

The US Navy still has cruisers, designated CG for “cruiser, guided missile”. There is talk of bringing the nuke cruisers back, then we’ll have the old CGN designations again.

Frigates were once designated as destroyer escorts, DE, but were redesignated FF for some reason or another. They are useful for littoral, or inshore, missions because of their shallow drafts.

Cruisers are classified according to their armor and armament. I’m sure that one of the members can give a better explanation than me.

3

Actually, today, it’s even simpler than that. There are only two kinds of ships. Submarines and Targets.

Mike K.

4

Yeah, I hear that a lot around here, it keeps up the morale for the crews of boats that are already sunk. Too bad that a sub’s main target is another sub. I’ve also heard that anti-sub helicopters make submariners pretty nervous.

5

Right! Probably the best overall categorization that can be done with ship classes is based on armor and guns, with the idea that any particular genre of ships (light cruiser, etc) should be able to fight on an equal basis its peers, defeat those of inferior class, and escape those of superior class. Of course, this meant that there was a constant effort to increase the capabilities of the chips of any particular class so that it could either catch those of inferior class, or improve armament so that a lighter unit could destroy a superior unit.

A ‘battlecruiser’ was originally called a ‘dreadnought cruiser,’ meaning it has a uniform heavy battery of guns (not mixed armament as previously) of battleship caliber (11" and up), the armor of an armored cruiser, and the speed of a cruiser. The result is a ship that made all armored cruisers obsolete, but which could not really stand up to a battleship (though it was intended that it could escape one).

The old armored cruisers (and pre-dreadnought battleships too) had a mixed armament of a variety of different calibers for engaging surface targets, such as 8", 6", 4" and a bunch of smaller quick firing guns. The problem with this is that it became difficult to hit a target, as the different calibers had different characteristics, so spotting the fall of shot and adjusting fire was tricky, to say the least! Armored cruisers were used as distant station flagships, and ‘ships of the line’ to flesh out the numbers of battleships if necessary, and were also used to hunt down the various forms of light cruiser (and in pre-dreadnought days, there were a lot of different types of cruiser, such as ‘belted,’ ‘protected’, ‘first class,’ etc, etc).

Heavy cruisers really didn’t develop until after WW1, though they have some relationship with the old armored cruisers. The big difference involves armament (which is essentially uniform, like the battlecruisers, but of ‘cruiser’ caliber), which was limited by the various post WW1 treaties to no more than 8", and tonnage, which was also supposed to be limited to 10,000 tons. Their mission was to operate as screening and scouting units, with enough power to push aside or drive off the scouting and screening elements of opposing forces, and have enough speed to escape battleships. A few ships managed to dodge the restrictions of the treaties, either because they were developed/built before the treaty rules were finalised, or in one way or another could not really be classified under the existing rules (‘pocket battleships’).

Light cruisers more closely embodied the ideal of a ship designed for scouting missions for the main fleet, with light armor and guns (no more than 6") and high speed. It could defeat a destroyer, and was often used by many navies as a ‘destroyer leader,’ or destroyer squadron flagship. As these ships were often as large as a heavy cruiser (though not as well armed or armored), they often worked in concert with heavy cruisers, and were also ideal platforms for AA defensive systems, leading eventually to the ‘AA cruiser.’ These were often used as escorts for carriers, etc…

6

Battlecruisers 101:

Admiral Jackie Fisher came up with the idea of the battlecruiser, a ship the size of a battleship with the speed of a cruiser. The trade-off, of course, was the removal of the armor. The mission of the battlecruiser was to be able to hunt down enemy cruisers by using the big guns to demolish them and the speed to prevent them from running away. In this role they performed superbly, including British victories at the battles of Heligoland Bight and Falkland Islands, both involving British battlecruisers that decimated German cruiser squadrons. But the “problem” with battlecruisers was the fact that they had battleship-caliber guns, and the temptation was too great to place them in a battle line alongside battleships with proper armor. At the battle of Jutland, the Invincible, Queen Mary, and Indefatigable were all lost with nearly all hands (all three exploded). The Germans (who chose to sacrifice gun calibe instead of armor for speed) lost one battlecruiser and the remaining four all suffered heavy damage.

Battlecruiser development was halted by all countries after the Washington naval treaty, with many battlecruisers and other large cruisers such as the (Glorious and Lexington) that were under construction being converted to carriers. The Japanese retrofitted the Kongo class battlecruisers to fast battleship standards. After 1930, with the development of “fast battleships”, only the Royal Navy continued to use the term “battlecruiser.” It should be noted that the Scharnhorst and Gneisenau were classified by the British as battlecruisers, due to the fact that they followed Germany’s pre-WWI idea of having battlecruisers with smaller guns and heavier armor.

The Alaska-class “super cruisers” had the same role as battlecruisers but instead of sacrificing something for speed, they were much more balanced, having armor, speed, and guns somewhere between battleships and heavy cruisers. But by the time the Alaska was completed, the aircraft carriers had pretty much done the job for them. The Japanese and Germans also had plans to build similar ships (the Japanese ships were to directly counter the Alaskas, the German design was meant to raid convoys). In the first years of the Cold War, despite their design being obsolete due to aircraft carriers as well as advances in missile technology, Joseph Stalin ordered several Stalingrad class battlecruisers to counter the Alaskas. These were never completed. The Kirovs are designated in the west as battlecruisers, most likely due to their size and firepower being between an Aegis cruiser and an Iowa battleship. The Russians have never used this term however, prefering to classify them as “large missile cruisers.”

7

Well, that’s the standard analysis. However, it’s not really convincing when you examine the facts. The Royal Navy continued to use the term ‘battlecruisers,’ because that’s what they were, and even though the ‘Kongo’ class was modernized by the Japanese, they did not upgrade their armor to anything like battleship standards (and paid for it at Guadalcanal), nor was the armor on the British battlecruisers on the same scale either (‘Hood’ had a heavy armor belt, but it didn’t help her against ‘Bismarck,’ nor was the ship designed for such missions). The ‘Alaska’’ class was designed to hunt down Japanese cruisers of the ‘Takao’ class and others, which by every measure were significantly better armed and faster than American heavy cruisers built, or building. And surely this is a classic mission for a battlecruiser!

Looking at German battlecruisers in WW1, they sacrificed very little in the way of speed, or armor, were able to survive enormous punishment at Jutland, and performed the role for which they were designed (screening the main fleet, engaging their opposite numbers, and brushing aside inferior opposition) magnificently. They did not ‘stand in the line’ with the battleships. The German battlecruisers of WW2 had a very different mission for that originially envisioned for the class, which was commerce-destroying, and the French built two battlecruisers of their own to address this threat (‘Dunkerque’ and ‘Strasbourg’). Really, a battlecruiser (or battleship) used for commerce-destroying is a very poor use of a very powerful and valuable asset, and is a role far better suited to auxilliary cruisers and submarines. This soon became clear to the Germans with the loss of ‘Bismarck,’ ‘Graf Spee,’ and the failure of ‘Scharnhorst’ and ‘Gneisenau’ to significantly destroy merchant ships.

British battlecruisers at Jutland were also used in the role for which they were designed (see above), but unfortunately, they just weren’t designed very well, nor did they take advantage of lessons learned in earlier battles (which the Germans did). They also did not ‘stand in the line’ with battleships either. In WW2, because of the enormous reduction in the size of the British capital ship fleet, battlecruiser WERE largely used as battleships, and paid the price for that misuse.

All that said, the vast reduction of capital ship fleets world-wide as a result of the Washington Conference and London Treaties meant that the original role of the battlecruiser was effectively redundant (no more large squadrons of battleships to screen, scouting missions taken over by aircraft, and battlecruiser tonnage was counted the same as battleship tonnage by the treaties), and that role was then essentially taken over by heavy cruisers. With the renewed increase in the sizes of fleets (particularly the US Navy) and the expiration of the treaties because of war, the limitations of the heavy cruiser soon became clear, and the same old requirements for the battlecruiser were recognized, and thus new battlecruisers were either planned, or built (Alaska and Guam), and this should tell you that the battlecruiser and its role was considered neither obsolete, nor ineffective by the world’s navies, but the opportunity to build them to fulfill the role for which they were designed simply hadn’t existed previously.

8

The distinction between heavy and light cruiser is purely a legal one. Washington Treaty and subsequent Lonon Treaty set limits on cruiser main gun caliber at 8" and 6.1" respectively. Forever afterwards cruisers whose main guns are 6.1" or less is called “light cruiser”, and those whose guns are between 6.1 and 8.0" are called “heavy cruiser”. There is no clear distinction in the intended role, in the weight, or in the effective firepower between light and heavy cruisers. Many of the light cruisers, such as US Cleveland, IJN Mogami and RN Colony classes, were substantially heavier and more powerful than many heavy cruisers.

The distinction between dreadnought battleship and battlecruiser started out clear, and gradually grew murky. At the beginning, dreadnought battleships were heavily armored, relatively slow beasts intended to stand in line of battle, and dish out and absorb punishment in a great slugfest with enemy battleships. Battlecruisers were lightly armored, fast ships meant to operate independently or semi-independently as an advanced scouting force for the fleet or as detached flying squadrons to protect colonies and trade lanes. Later battleship and battlecruiser roles merged into the “fast battleship”.

“Pocket” battleship is a propaganda name. It refers to a special class of German cruisers and was coined in British press to make these ships sound more omnious.

US Navy still has cruisers (CG), destroyers (DDG), frigates (FFG) and littorial combat ships besides carriers and submarines.

9

However, I do believe the “pocket” battleships were armed to the same high degree as the Bismarck, correct? And then there are “destroyer escorts”—wft?

10

No. ‘Graf Spee’ and her sisters had 6 x 11" guns, while ‘Bismarck’ had 8 x 15" guns, extremely heavy armor, and was quite fast. ‘Graf Spee’ could only make 26 Knots…

11

Well, this is not really true either. The London conference of 1930 was intended to limit the number of heavy cruisers built. In the case of the US and Japan, this initially meant going to a cruiser that was as large as a heavy cruiser, but armed with light cruiser guns (Uss Brooklyn and the Mogami classes). However, the Japanese had no intention of this being in any way a permanent situation, and specifically designed their ships for replacement turrets with 8" guns which could be quickly switched out, and thus become heavy cruisers in short order. Strangely and by coincidence, the hull and machinery of a ‘Brooklyn’ class light cruiser was eventually used to produce a heavy cruiser as well, USS Wichita.

All that said, you are right in that the US never really wanted to build light cruisers per se, as it was felt the heavy cruiser was better for the job envisioned and the subsequent ‘Cleveland’ and other classes that were built after the London Treaties were abrogated by the war in Europe were just as big as heavy cruisers. However, the light cruiser performed very specific functions in other navies, particularly the Japanese, and thus really were a very different ship. In the Japanese navy, the light cruiser was used as a destroyer squadron leader, was armed with torpedoes like a destroyer, and was intended to provide protecting gunfire for the destroyers of its squadron while being able to match the speed and maneuver with the destroyers. Thus, Japanese light cruisers were significantly smaller and weaker than American light cruisers (most Japanese light cruisers were in the 5,500 ton range, while US light cruisers were mostly in the 10,000 ton range).

The ‘fast battleship’ actually took on a new role, which was neither that of the battlecruiser, nor in keeping with the more traditional battleship (and didn’t do either particularly well)

12

Destroyer escorts are destroyers that are designed and armed primarily for anti-submarine operations and used for escorting convoys.

13

Not entirely. In USN service the DEs were almost literally half a destroyer… one fire room, one power plant, instead of two. No directors for the main guns, which themselves were smaller. While initially designed for largely the ASW role, DEs were later changed into variants such as DERs or APDs.