German Battlecruiser Concept

[Kentucky-roughrider]

What was the concept of the German Battlecruiser design? There was several different ideas posted on the other thread but I never saw one hammer down as the real concept.

[Tony Williams]

I suspect that the principal reason for their development was that the Royal Navy was building BCs, and the Kaiser wanted to match whatever capabilities the RN had...

 

They were, of course, somewhat more balanced designs than the British BCs, sacrificing some hitting power for better protection.

[FlyingCanOpener]

What was the concept of the German Battlecruiser design? There was several different ideas posted on the other thread but I never saw one hammer down as the real concept.

 

I know I'm going to essentially repeat what Tony said, but...

 

Essentially the German concept of the battlecruiser was the same as the British battlecruiser: Be faster than whatever can outshoot it and outshoot whatever it can't outrun. However, the German capital ship design rested on the idea that survivability trumped all other concerns, including firepower, so you had ships that were far more heavily armoured than their British counterparts, at the main expense of armament. For example, HMS Invincible sported 12" guns as opposed to SMS Von der Tann's 11" guns. Then whenever you look at armour, you see SMS Von der Tann had 2.5'' deck and 10" belt, whereas HMS Invincible had 2" deck and 6" belt armour. Where it gets interesting is that SMS Von der Tann was a full knot faster than HMS Invincible.

 

Things get interesting at the end of World War I, when the Mackensens and the Ersatz Yorcks sit on the drawing board with 14" and 15" guns, respectively, but with similar armour to British ships like HMS Renown and Hood (Designed to counter these ships).

Edited January 4, 2012 by FlyingCanOpener

[Ken Estes]

Well, nothing has similarly weak armor as the Renowns, except the later US Lexingtons. I think the Germans were just continuing their annual shipbuilding programs with names replacing wartime losses in several cases. They were further evolutions of Derfflinger, going to the 15-inch with erz. Yorck as you say, because of the new UK construction.

 

We also need to recognize the position of the armored cruiser vs. predreadnought ships in the major navies, and the example taught by Togo in using Kamimura's cruisers as the fast van of his battle line, helping to cross the T if possible in fleet engagements, also capable of chasing down raiders such as Rurik.

[AdmiralB]

the German capital ship design rested on the idea that survivability trumped all other concerns, including firepower, so you had ships that were far more heavily armoured than their British counterparts, at the main expense of armament.

 

German ships of the era were also designed with the understanding that they'd not be operating too far from home, were they not? You can build a better-protected ship for a given external envelope when you don't have to allow for berthing accomodations for around-the-world cruises.

[FlyingCanOpener]

Well, nothing has similarly weak armor as the Renowns, except the later US Lexingtons. I think the Germans were just continuing their annual shipbuilding programs with names replacing wartime losses in several cases. They were further evolutions of Derfflinger, going to the 15-inch with erz. Yorck as you say, because of the new UK construction.

 

Nice catch. It was after 1 this morning and I was tired. But what's interesting about the Mackensens is that it was essentially an upgunning of the Derfflingers with better powerplants rather than the German tradition of uparmouring even slightly as the ships developed. As a result, when you look at the Ersatz Yorcks (They never came up with a true class name, didn't they.) and compare them to HMS Hood, their armour layouts are similar or even deficient in some respects (12" belt 12" turret 1" deck as compared to Hood's 12" belt 15" turret 3" deck), and with Hood's higher top speed, they would have been in deep trouble.

 

For the Germans, was this a wartime decision of allocation of resources, a change in design philosophy, or even just that the limit of battlecruiser design was hit with these ships?

[AdmiralB]

compare them to HMS Hood, their armour layouts are similar or even deficient in some respects (12" belt 12" turret 1" deck as compared to Hood's 12" belt 15" turret 3" deck), and with Hood's higher top speed, they would have been in deep trouble.

 

 

Did Hood come off the drawing board with that arrangement? Seems like it was revised at some point and up-armored, but I don't recall at what point in her life.

[FlyingCanOpener]

Did Hood come off the drawing board with that arrangement? Seems like it was revised at some point and up-armored, but I don't recall at what point in her life.

 

Off the drawing board? No. She essentially was designed with Lion's armour layout but with improved belt (the 12" belt as opposed to 9"), and the deck armour was strengthened as she was being built through laminate armour. I want to say though that the turret armour was 15" from the beginning as thumbing through Jane's and a couple other books and piddling about online came up with no upgrades to the turret armour.

Edited January 4, 2012 by FlyingCanOpener

[Olof Larsson]

It would seem to me that the Royal Navy started out with BC's designed to outfight ACR's,

and to fight BB's under favourable circumstances,

while the germans started out with BC's designed to fight BC's,

and to fight BB's under favourable circumstances.

 

As far as the german 11" vs. brittish 12",

the germans initially had (pre Jutland AFAIK) superiour AP-shells.

[Detonable]

I think the idea was the same as the British - fight through the cruiser screen of the enemy fleet, report the size and course of the enemy fleet, and escape. Perhaps the Germans recognized that due to their smaller fleet the British would eventually secure the battle area, and any ship that couldn't get home under its own power was lost. So their ships were better armored.

 

I get the impression that German guns were frequently quite accurate, and so they could put smaller guns on their ships and still hit at long ranges. Is this correct?

[CT96]

...

I get the impression that German guns were frequently quite accurate, and so they could put smaller guns on their ships and still hit at long ranges. Is this correct?

 

The Germans had very high quality Zeiss Optics for their fire-direction (I recall reading of the brits acquiring Zeiss Optics through neutral Switzerland during the war) - which I understand to have given the Germans superb aiming ability vs. the RN fire direction system (lots of complicated explanation of the competing systems omitted due to lack of timely recall).

[DB]

German range finding equipment was stereoscopic, British was coincidence.

 

There is much thought that stereoscopic is superior providing that operators are properly trained and well rested and that coincidence is easier and may be more useful as operator limitations are reached through tiredness, etc.

 

At Jutland, the sun position (by which I mean a light horizon) and wind direction seem have been more significant factors in determining the effectiveness of spotting range finding, rather than equipment design differences.

[Mobius]

As far as the german 11" vs. brittish 12",

the germans initially had (pre Jutland AFAIK) superiour AP-shells.

It appears the British got a better AP around 1912. Then the 12" was about equal out to 7,000 yds and at 15,000 penetrated about 1" better.

[Tony Williams]

I recall reading that the German guns were optimised for short to medium ranges, which is what was expected in typical North Sea conditions. They fired relatively light shells at a high muzzle velocity, giving them a flat trajectory, a better hit probability and better penetration of vertical armour at such ranges. The British guns tended to fire heavier shells at a lower velocity which carried their velocity better out to long range, where they plunged downwards at a steeper angle making them more effective against horizontal armour.

[Getz]

I remember reading that the Germans designed their Battlecruisers to be able to fight in the "line of battle" if required (rather like Togo's ACRs at Tushima) and that meant they had to be armoured against 12" gunfire. That said, I think the Germans also had a clearer eyed appreciation of what was required for a battlecruiser to do it's job and part of that was sufficient armour to stand up to a similar vessel - for all the fact that the Invincibles were the first battleruisers, it shouldn't have taken a great deal of imagination to realise that at some point they might have to fight something designed to fight them...

[Ken Estes]

North Sea conditions certainly affected German warship design. This is mentioned in the work of Constructor Hadeler in designing CV Graf Zeppelin. The broadside casemate 5.9 inch batteries were incorporated specifically because an enemy cruiser could come upon it in the fog and gloom, even when escorted properly.

[Tony Williams]

North Sea conditions certainly affected German warship design.

One thing I recall reading about the design of the early German dreadnoughts is that their natural roll period accidentally harmonised with the typical wave pattern in the North Sea, which meant that in a beam sea the ships rolled more and more until they were in danger of capsizing in quite moderate seas. They had to fit them with bilge keels rather quickly to slow the period of roll.

[glenn239]

Philbin in Inconvienient Hero goes into German doctrine (or lack thereof) on the role of battlecruisers in the German navy. Recommended for anyone here whose not read it.

[Arminius]

Its not only the Armour scheme ...

 

the German BCs were superior in the subdivision of their ships.

 

Something neglected in British ship design.

 

So they ( the German ships ) remained afloat ... not only the BCs of WW I, also the Bismarck, Scharnhorst ... ( Exception: Blücher ) ... until damage beyond any design considerations was done.

 

Any British and Japanese ship ( of WW I or WW II ) was going down with much less hits!

 

Hermann

 

P.S.: until WW II the German ships were especially superior in underwater protection. IIRC only the Nelsons ( above Treaty limits with this feature ) and improved QEs were comparable ( added Bulges or Torpedo Belts? ) ...

 

Hermann

[Tiornu]

for all the fact that the Invincibles were the first battleruisers, it shouldn't have taken a great deal of imagination to realise that at some point they might have to fight something designed to fight them...

Fisher was certainly a man of active imagination, but he doesn't appear to have wasted much time trying to form a coherent understanding of some issues.

[cjpaul]

The Derrflinger class was probably the best all-around capital ship design of WWI. Fast, well-armored and survivable with enough firepower. Speed is, as it turns out, the most important characteristic in regards to usefulness. In both WWI and II it was the faster capital ships that were always tasked with the more important duties. Even the Iowas were more battlecruiser than battleship.