Bismarck and her contemporaries

[Bgile]

Would she really? I'm not so sure. Several of the hits were at or below the waterline and would have let in considerable water all on one side.

me neither... I imagine Bismarck would be similarly crippled, except she wouldn't flood nearly as bad. at that close a range, her extra armor would mostly provide more big chunks of shrapnel for perforating her own interior. At 8K yards, nothing on Bismarck is resistant to a 16"/45 - I suspect her barbettes, turrets, magazines and powerplant are just as vulnerable as Kirishima's.

Well, according to Nathan Okun's calculations Bismarck's magazines were well protected against pretty much any shell hits and the same can be said for her power plant. The two exceptions are shells going under the belt and long range shells going through the deck. Neither of those would be a problem at 8,000 yds. Her turrets and barbettes were vulnerable, and of course everything above the main armor deck. The difference is that her guns were much more powerful than Kirishima's and her potentially high rate of fire might be significant at short range. The IJN were very good at night fighting, but the Germans had radar.

[lwd]

...Well, according to Nathan Okun's calculations Bismarck's magazines were well protected against pretty much any shell hits and the same can be said for her power plant. The two exceptions are shells going under the belt and long range shells going through the deck. Neither of those would be a problem at 8,000 yds.

Looking at the diagram at:
http://www.navweaps.com/index_lundgren/ ... alysis.pdf
I count 7 hits on or below the water line some fairly deep. Given Bismarck's greater length if you superimpose them the rudder hit is probably going to get hull as well. I'm not up enough to know if it's likely to hit below her belt but I suspect so.

...The difference is that her guns were much more powerful than Kirishima's and her potentially high rate of fire might be significant at short range. The IJN were very good at night fighting, but the Germans had radar.

SoDak has a good chance of being in worse shape but that's not what's being discussed right now.

[yellowtail3]

looking at that Navweaps page on the 16"/45, shooting AP shells as Washington was - and at the diagram of 16" hits on Kirishima, and replacing her with Bismarck? - I don't think it much matters where they hit, they're going to punch through at 8K yards.

[Bgile]

looking at that Navweaps page on the 16"/45, shooting AP shells as Washington was - and at the diagram of 16" hits on Kirishima, and replacing her with Bismarck? - I don't think it much matters where they hit, they're going to punch through at 8K yards.

That is where I believe you are mistaken. According to Nathan Okun's calculations, it was impossible for a shell to penetrate Bismarck's main armor belt, scarp, and then the holding bulkhead. At range = 0.

[lwd]

looking at that Navweaps page on the 16"/45, shooting AP shells as Washington was - and at the diagram of 16" hits on Kirishima, and replacing her with Bismarck? - I don't think it much matters where they hit, they're going to punch through at 8K yards.

That is where I believe you are mistaken. According to Nathan Okun's calculations, it was impossible for a shell to penetrate Bismarck's main armor belt, scarp, and then the holding bulkhead. At range = 0.

Indeed however the failure to benetrate the scarp may create a situation that's even worse in some ways for Bismarck. Unless I'm wrong it's below water level. If it rejects the round the round will then either fragment or rickochet violating the water tight integrity of that level. That means you have a water tight compartment below a flooded one. This is not a particularly good situation stability wise.

[Bgile]

looking at that Navweaps page on the 16"/45, shooting AP shells as Washington was - and at the diagram of 16" hits on Kirishima, and replacing her with Bismarck? - I don't think it much matters where they hit, they're going to punch through at 8K yards.

That is where I believe you are mistaken. According to Nathan Okun's calculations, it was impossible for a shell to penetrate Bismarck's main armor belt, scarp, and then the holding bulkhead. At range = 0.

Indeed however the failure to benetrate the scarp may create a situation that's even worse in some ways for Bismarck. Unless I'm wrong it's below water level. If it rejects the round the round will then either fragment or rickochet violating the water tight integrity of that level. That means you have a water tight compartment below a flooded one. This is not a particularly good situation stability wise.

I think that's correct and I've always felt that Bismarck would have eventually lost stability due to that effect and the many other compartments outside that system which were probably flooding.

[alecsandros]

Given the same situation - Bismarck firing at SoDak, Washington firing at Bismarck - I think the German high rate of fire, good grouping and very high AP power would at least deliver heavy damage to SoDak (if not actualy sinking her). However, the MKVII super-AP shell would severely maul the Bismarck, and, at the least, leave him with a 20 degrees list and a top speed of 15 kts.

As for the comparison between Bismarck's and Kirishima's armor, they are not that close... The Kirishima was an aging battlecruiser, with the thickest armor in the barbettes (9"), and a main belt of max 8". They were very weak by WW2 standards, both in terms of armor and guns.

All the best,

[Karl Heidenreich]

This thread was started in order to fight the generally spread notion that Bismarck was “just” a derivative of the Baden-Bayern design but, since a few months now, I have doing some research in several types of this great ship´s contemporaries. So far the Nelsons, KGVs Lions, Yamatos and Schanhorsts have been addressed with their strengths and weaknesses. By no way that means that I pretend to be an expert, but I can say that my knowledge on these regards have improved, indeed.

The intention was to address Bismarck at the last, and then expect the overwhelming response of it´s detractors, but it will not be so and will be addressed immediately because, so far I have not yet done any serious insights on the American BBs directly, only as necessary comparisons had been brought by the consulted authors. That is, basically, because I lack of the appropriate information on these ships - specially the Iowas and the never built Montanas - and the one that normally “flies” in the internet warship community is not the best, so far. Friedman, Raven, Garzke, Dullin, Roberts, Worth are those that, in contact with primary information, need to be consulted and studied. We may also need to measure the weight of the new “revisionist” tendencies. In some cases new information has been available which is good, but in other cases new interpretations, gratuitous ones, have come with no other purpose than to confuse things more.

So far this thread have helped me to understand better the dynamics of design and the politics of naval construction after WWII. A side effect have been the issue of the Treaties, which were far more important than originally considered by me. Both naval powers, the US and GB, seriously abided these treaties when other countries only abide them knowing that sooner or later they will ignore the limitations imposed.

On the other hand I must say that, even as a Bismarck fan, I must admit that it´s construction (and that of Tirpitz and likely the Twins also) do not seem as relevant when compared with other projects that could have helped more the German war effort. The resources integrated in these ships, quantified if wished in some 41,673 tons of Bismarck´s displacement plus some 42,343 tons of Tirpitz (mainly machinery, guns and armor) could have produced, by mid 1941 some 109 Type VII U-Boats. The German surface raiders never were as close as the U Boat arm to produce a catastrophic effect to the British. If, in a single stroke the Germans could have deployed, at least half these quantity (plus those finally and historically deployed), the course of History could have been another one. Of course we need not only address material resources but also training of 109 crews, officers, logistics, fuel and fueling, port facilities, etc. etc. It is as a tempting thought as that of getting those resources and build 1,339 Tiger I tanks (62,72 tons each) that could have been those necessary for Manstein to break the Stalingrad siege (as per an example. Most likely Bismarck and Tirpitz could have been able to produce some 3,307 units Panzer III units (25,4 tons each) that could have changed the Eastern Front as early as October-November 1941). I do regard the U Boats, the Mk III or many more Messerchmitts Bf 109 winner projects and moves. Bismarck and Tirpitz are glorious but unnecessary ones.

The US could build, whatever it´s end quality, some 10 Battleships near the start or during WWII plus a couple of battlecruisers of dubious worth. Also they were able to build a large quantity of the real predominant naval weapon, the aircraft carrier, in number superior to 24 plus many more smaller CV units. With those, plus the air superiority weapons, destroyers and cruisers, the USN was able to mount the most formidable navy that has ever dominate the seas (and it beats me why they let the Russians go their way after the war…). During that same period the Germans were able to produce zero battleships, zero aircraft carriers. Those resources were pretty valuable for the Germans and, in my humble opinion, they were misused.

Bismarck and Tirpitz became realities and legends. And it seems to me that being the only two real battleships the Germans had during WWII (Schanhorst and Gneisenau were under gunned and no match for even the lesser British BBs) these legendary status is what brought so much attention to them. Good and bad one.

According to James Cameron´s documentary the Bismarck was the “Death Star” of it´s age. Aside from the ridiculous claim made by Cameron it´s clear that she was not. According to it´s detractors Bismarck was just a lousy design lucky enough to blow a very weak Hood with a lucky hit. Luck that ran out when the Swordfish torpedo blew her rudders and jammed her. Of course this affirmation is as valid as the Death Start one. The reasons to support this mid way position are going to be explained in the following post. It is based in two main sources: this website information from José Rico and William Garzke and Robert Dullin book. There will be some ideas extracted from previous quotes from Friedman and Raven & Roberts, the Baron and Breyer.

[Karl Heidenreich]

The Bismarck Class


By the mid thirties the Germans were not considering to engage the British in a battle for the supremacy of the North Atlantic. Their main concerns were the French and the Italians and that´s the way the focus their design and naval construction efforts with the Deutschland Class and Schanhorst Class. Even the latter was armed with sub standard guns in order to gave the British a “token of good will” if that could be applied to Hitler.

The Germans were not signatories of the Washington and London Treaties because, in the twenties and thirties Germany was far away to be a naval power. Even France or Italy were more a power than Germany. But by 1935 they signed the Anglo German naval Treaty that bound them, indirectly, to the other treaties. The basic premise after the signature of the treaty was the Germany could build a 35,000 ton battleship with guns up to 355 mm. After the failure of Japan and Italy to sign the 1936 London Naval Treaty the escalator clause allowed the signatories to build a BB as big as 45,000 ton in displacement and 406 mm guns. For instance the USN announced that they will arm their originally 14” gun intender North Carolina Class with 16” armament. It was, legal, for Germany to build a ship as big as a 45,000 ton BB. The attempt of the British to bring a new limit of 40,000 tons in 1938 was rejected by the Germans. By then Japan was building their Yamatos, that would be the greatest BBs ever to be sail.

The Germans, by 1932, recognized the same design concept already reached by the British that a 35,000 ton standard displacement ship will serve well with 305 mm guns. The British were pushing for all European navies to limit themselves to such an arrangement but neither were willing to accept. The French were building their 330 mm battlecruisers and the Italians were using 381 mm guns. The German design protocols called for a 41,000 ton ship considering armament of 350 mm.

Hitler himself made clear that the armament could not be less than that of the French and Italians, so that the 380 mm was the chosen armament. The attempts and exercises the Germans did gave results that such a 380 mm armed ship would be of a 45,000 ton displacement. This process is very interesting if we study the approach the British did from 1921 to 1940 with their own designs going from Nelson to the Lions.

Aside from the gunnery approach, which was the controlling factor in the German effort, other elements were studied as the machinery. The Germans were pretty interested in turbo electric drive as the ones intended or used in Lexington, Saratoga or in the liner Normandie. Other naval engineers thought that the diesel approach would be more fuel efficient and even hybrid systems were considered.

The Germans had an important background experience from Jutland and they were monitoring the naval trends of other navies regarding gun size, armor, machinery and the self imposed limitations.

From these experiences and by the following of their contenders the Germans became convinced that the new BBs must not be a triple turret arrangement but return to what their (and British) gunnery experts regarded as the best arrangement: four twin turrets. According to Garzke and Dullin this arrangement allowed the Germans to:

“
• Ammunition supply in the gun chamber was considerably simpler than in triple turrets.
• Two twin turrets aft would have a larger number of rounds available than one triple turret. A triple turret forward made it difficult to stow powder and projectiles in the slender hull.
• Four twin turrets permitted better organization of firepower, either the two forward and two after turrets, or one of each, could form a battery.
• There was less chance of firepower loss as a result of turret damage.
• It was technical possible to fire one barrel from each turret in a salvo, and fire the other barrels in another salvo, but this was not provided for, as alternate firing, of the barrels in each turret would disrupt firing procedures and reduce the salvo rate.”

This statement echoes Friedman comments on the possible arrangements used by then:

1. French quadruples all concentrated in the front of the ship
2. British use of 16” triples in the Nelson´s
3. British use of two quadruples and one twin in the KGV
4. The US use of the triples turrets

It is obvious that the triple gun arrangement main advantage was that of reducing general displacement and shortening the citadel. That was the main reason the British used it in their Nelson´s with very bad results, bad enough for them to want never to use that system again. It was again considered, however, in their Lion´s design but with a much greater displacement.

From the point of view of the gunnery experts the twins represent a more formidable arrangement with the disadvantage that it gives a longer citadel and an increased overall displacement.

There is another reason, in addition, to the German rejection of triple or quadruple arrangements: they considered that these will produce a larger cut in the strength deck to accommodate the barbettes. “Such a concentrated battery, aside from the devastating blast effects on adjacent structures, would have increased the risk of losing more guns due to damage to any one turret” (G&D, page 278).

Returning to the design process the main battery arrangement resembled that of the Baden Bayern Class as it was it´s three propeller propulsion arrangement.

“This development has resulted in some speculation that the Bismarck Class battleships were mere copies of the these older ships. This is false: the new ships had to be faster and have more protection, range, and gunpower. The percentages allocated to armor protection, propulsion and armament were not the same.” (G&D, page 204)

Design work on Bismarck was finished on November 16th, 1935 (74 years and a day from the day I´m writing this) and Tirpitz on June 14, 1936.

Characteristics of Bismarck

Standard displacement: 41,673 tons
Design displacement: 45,202 tons
Full load displacement: 49,136 tons
Battle Load displacement: 50,129 tons
Waterline length: 241,55 mts
Waterline beam: 36 mts
Draft: 8,7 mts standard
9,30 mts design
9,99 mts full load
10,17 mts battle load
Depth: 15 mts.
Armament: 8 x 15”/47 4 x 2 (380 mm)
12 x 5,9”/55 twins
16 x 4,1/65 twins
12 x 0,79” single
Four Arado Boatplanes
Speed (normal): 29.0 knots
(maximum) 30,12 knots
Shaft horsepower: 136,200 normal maximum
147,900 overload
Endurance: 9,500 nautical miles at 19 knots
Fuel capacity: 8,167 tons


Armament specs:

15”/47 model 1934 main guns.
Shell weight: 800 kgs (1,764 pounds)
Muzzle velocity: 820 mps
Maximun range: 36,520 m
Elevation: 30 degrees.

“The armor piercing shells weighted 800 kilograms, lighter than those of most World War II 380-381 mm guns. However, improved ballistic qualities gave the German increased muzzle velocity and additional range. The increased muzzle velocity caused a rather flat trajectory, suitable for combat in the North Sea.” (G&D, page 275)

“The main battery guns held the same superiority over the British counterparts as had been the situation during World War I. What one navy can do, another can, but for some reason British gun development lagged behind that of Germany during the interwar period…” (G&D, page 299).


Protection:

The Germans emphasized the close in combats expected in the North Atlantic as well as provisions for adequate torpedo protection and subdivisions.

The German Krupp armor was of very good quality. With the adding of molybdenum to the original chrome-nickel alloys, the cemented and non cemented armor plates were of greater resistance, at least 25% stronger than those of WWI, against shells striking at all angles.

One controversial issue regarding Bismarck armor design is, still, that the Germans didn´t went along with the common procedure of the All or Nothing armor scheme but with the space arrayed one. The AoN scheme, which was of common practice in all the contemporary navies by then presented the advantage of being weight economic and helped to shorten the armored citadel. However the space arrayed presented some design paradoxes that made it, for the Germans, desirable over the AoN scheme. For the Germans it was this arrangement the so called turtle deck with the main side belt vertical, “with the bulge incorporated into the lower underwater hull structure and a thinner upper citadel belt superimposed between the two upper decks. The horizontal protection was provided by a two deck armor system with an intervening non ballistic deck” (G&D, page 283)

According to this comment from the legendary Baron Mullenheim Rechberg´s coment in his book “Bismarck, a survivor story” (page 35):

“the upper deck was reinforced by armor that ran almost it´s entire length. This armor was only 50 mm thick but it provided protection against splinters and would slow down an incoming projectile so that it would explode before striking the armored deck below, which protected the ship´s vital spaces.”

This echoes also the work edited by S. Breyer “Marine Arsenal: Special Volume 6: The Armor of German Warships 1945” where there is the following statement of a German engineer on the Bismarck Class armor on the Tirpitz test shots on the target ship Hessen:

“ The entire arrangement of armor aboard the target ship Hessen was such high quality, that in the year 1941 it tolerated 9 direct hits from 380 mm projectiles without failures and the following day 7 more hits. The heavy shells penetrated the forward section and the upper deck armor… however not the underlying panzer deck. Both shoots occurred at a distance of 25,000 meters”

This is also mentioned in G&D, page 285:

“Based upon proving ground tests, German naval constructors believed that the 50 mm upper armor deck would be thick enough to initiate fuze action and detonate bombs above or on the lower armor deck”

Side and underwater protection

One of the features that draw more attention to Bismarck, is her underwater protection, specially regarding her rudders. A lot of speculation has come from this.

Bismarck was designed to withstand to resist 250 kg of TNT. It´s broad beam permited a much better ATS sytem than that of slender hulls, as those subjected to the Panama Canal width limitations.

The bulkhead thickness at the main ships sections was of 2,09” plus the torpedo bulkhead thikness of 1,77”.

Bismarck was provided with a standard double bottom 1,7 meter deep.

The rudders were inclined at 8° from the vertical and were connected to the steering motors by transverse shaft and coupling. In agreement with Mr. Jurens assessment the torpedo hit vented into the ship, damaging the steering motors and their foundations.

According to Garzke and Dullin:

“ Rudders are the “Achilles heels” of all warships, and no effective means for their protection have yet to be found. Rudder vulnerability and it´s consequences were demonstrated in the loss of steering of Bismarck and the damage sustained by the Tirpitz during the X craft attack. After the loss of Bismarck, German naval constructors concluded that it was not possible to protect the rudders against weapons then available. Studies were more concerned with the separation of a jammed rudder from the ship´s hull by special explosive charges."


Even the USN recognized that the Bismarck´s armor scheme was very good.

“In general, the US Navy felt that the magazines and propulsion plant were well protected against this 406 mm gun…” (G&D, page 283).

What follows I regarded as very important, probably vital:

“The heavier lower belt 320 mm case hardened nickel steel in the Bismarck and 315 mm in the Tirpitz…
… Questions have been raised as to the wisdom of providing a vertical side belt of less than the traditional standard – thickness equal to the bore of the main battery. Gunnery tests of the new composition KC n/A 320 mm armor plate showed that it´s thickness and resistance capabilities equaled the optimum thickness of 360 mm, but as thickness increased, little was gained (to the point of diminishing return). Krupp considered the thickness of 320 mm to be optimum and 400 mm neared the limit of effective production” (G&D, page 283)

Admiral Karl Witzell, chief of German Navy´s bureau of Ordnance supported this criteria and wrote to Garzke and Dullin specifically on this regard.

About the deck armor was arranged as follows:

Bismarck over machinery
Upper 50 mm (as mentioned by Mullenheim and Breyer)
Armored 80 mm

Bismarck over magazines
Upper 50 mm
Armored 95 mm

In Tirpitz the armored over magazines increased in 5 mm more.

“The armor slopes considerably reinforced the moderately thick side armor belt. Such an arrangement was intended to increase the protection against high angle hits on the side armor belt, where a shell would be exploded, ricocheted, or rendered inert. It also provided increased protection against bombs for the wing fuel oil tanks and the side protection system. As a result, the Bismarck class ships were exceptionally well protected against close range shell fire.” (G&D, page 285).

Herein attached some information, available from this (José Rico´s) website, is presented in a comparative way:

Bismarck armor scheme:
Main belt armor 320 mm
Turrets 130-360 mm
Upper Deck 50 - 80 mm
Armor Deck 80 120 mm
Protected Length 70%
PC/TC 17/22
Armor weight. 17,540 tons

Richelieu armor scheme:
Main belt armor 330 mm
Turrets 170-430 mm
Upper Deck 24 mm
Armor Deck 150 mm
Protected Length 54%
PC/TC 10/21
Armor weight. 16,400 tons

Vittorio Venneto armor scheme:
Main belt armor 350 mm
Turrets 130-380 mm
Upper Deck 45 mm
Armor Deck 112 mm
Protected Length 55%
PC/TC 8/18
Armor weight 13,545 tons.


North Carolina armor scheme:
Main belt armor 305 mm
Turrets 178 – 406 mm
Upper Deck 37 mm
Armor Deck 104 mm
Protected Length 60%
PC/TC 9/18 ?
Armor weight 15, 087 tons

KGV armor scheme:
Main belt armor 348-374 mm
Turrets 150 – 324 mm
Upper Deck -
Armor Deck 124-150 mm
Protected Length 59%
PC/TC 10/21
Armor weight 12,612 tons

In order to finish this post it´s important to do it with G&D´s closing comment (page 303):

“The Bismarck and Tirpitz, while not the most powerfull battleships ever built, were good fighting ships, with many design innovations and well trained crews. Despite their deficiencies, the exploits and dramatic careers of the Bismarck and Tirpitz have made these ships near legends in modern naval history”.

Warmest regards,

Karl

[yellowtail3]

The Bismarck Class
• There was less chance of firepower loss as a result of turret damage.

if they were concerned with firepower loss from turret damage, you'd thinking the German designers would have been a little less niggardly with the turret/barbette armour

“The Bismarck and Tirpitz, while not the most powerfull battleships ever built, were good fighting ships, with many design innovations and well trained crews. Despite their deficiencies, the exploits and dramatic careers of the Bismarck and Tirpitz have made these ships near legends in modern naval history”.

I think that means, "they weren't useless" or something close to that. I'm not sure what was particularly innovative about them. I think the Bismarck's were pretty ships; just because they weren't quite at advanced as their competitors, doesn't mean they weren't good ships. And I agree: the resources that went into them would have been better put just about anywhere else. A hundred subs? I don't know if they had the shipyard capacity - and a hundred U-boats will require twice as many men as Bismarck - but they'd have done more good. I'm glad they built the Bismarcks, though.

[dunmunro]

Armour weight calculations are problematic. Direct comparisons are always difficult because each navy used different methods of weight calculation. For example some navies would include protective plating such as STS steel as armour, while others would include it as hull weight. Here's a comparison of KGV and NC done using the same methods of calculation:

http://en.wikipedia.org/wiki/Comparison ... h_Carolina

It is highly unlikely that Littorio carries more armour than KGV, for example, as Littorio's main belt is only about 4 metres deep versus 7 metres for KGV and while her turrets and barbettes are thicker, these are small in area compared to the main belt.

KGV's upper deck is 30mm and there is an additional 38mm splinter deck directly over the magazines.

[alecsandros]

@dunmuro
Though I think you're right about the various ways armor was accounted, there are some big differences, that clearly tell us an important story: for example, the difference between Bismarck and Littorio are of about 3000 tons. That's a lot of armor, and I think it unlikely that Littorio's armor would be so severely under-estimated.
Another think we should be taking in consideration (though very hard, at least for me, to analyze and understand properly) was not only armor quantity, but also armor quality.

All the best,

[Thorsten Wahl]

The Bismarck Class

Admiral Karl Witzell, chief of German Navy´s bureau of Ordnance supported this criteria and wrote to Garzke and Dullin specifically on this regard.

About the deck armor was arranged as follows:

Bismarck over machinery
Upper 50 mm (as mentioned by Mullenheim and Breyer)
Armored 80 mm

Bismarck over magazines
Upper 50 mm
Armored 95 mm

Bismarck armor scheme:
....
Armor weight. 17,540 tons
Warmest regards,

Karl

armor
Bismarck upper deck over magazines is 80 mm not 50 mm
armor weight of ~17.540 t (metric) does not include roughly 1600 t turretarmor(Drehpanzer)
for bismarck the 17.540 statement doesnt differenciates between armor relatet armormaterial and hull and superstructure related armormaterial
which i'd expect around 1000 t

recently I started to try a calculation on armor
here

http://forum-marinearchiv.de/smf/index. ... #msg113953

I would expect the US armormasses something higher as the comunicated values

some data may be incorrect due to roundings and estimates
more information welcome

[Herr Nilsson]

Bismarck upper deck over magazines is 80 mm not 50 mm

I don’t think so. The revised B.B.V. (special design specification) contains still no reference to it. There is just an 80 mm plating around the MA turrets II and III mentioned. In case of Bismarck the armour deck - at least around turret C and D - was definitely increased up to 100 mm.

[dunmunro]

recently I started to try a calculation on armor
here

http://forum-marinearchiv.de/smf/index. ... #msg113953

I would expect the US armormasses something higher as the comunicated values

some data may be incorrect due to roundings and estimates
more information welcome

KGV's main belt and deck is 126.5 metres long. There is an extension to the main belt and armoured deck forward and aft, which adds another 23.5 metres, with an average deck and belt thickness of about 100mm, and 2.9 metres deep. There is armoured deck forward and aft of the extension, of another 33 metres at an average thickness of about 75mm.