WesWorld

Don Juan D'Austria, Iberia BB laid down 1930

Displacement:
31,361 t light; 33,101 t standard; 35,939 t normal; 38,065 t full load
Loading submergence 1,541 tons/feet

Dimensions:
787.40 ft x 98.43 ft x 27.89 ft (normal load)
240.00 m x 30.00 m x 8.50 m

Armament:
8 - 13.78" / 350 mm guns (2 Main turrets x 4 guns)
24 - 5.12" / 130 mm guns (6 2nd turrets x 4 guns)
24 - 2.24" / 57 mm AA guns
32 - 1.38" / 35 mm guns
Weight of broadside 12,252 lbs / 5,557 kg

Armour:
Belt 15.75" / 400 mm, ends unarmoured
Belts cover 97 % of normal area
Main turrets 15.75" / 400 mm, 2nd turrets 3.94" / 100 mm
AA gun shields 1.57" / 40 mm, Light gun shields 0.79" / 20 mm
Armour deck 4.72" / 120 mm, Torpedo bulkhead 0.79" / 20 mm

Machinery:
Oil fired boilers, steam turbines plus diesel motors,
Electric cruising motors plus geared drives, 3 shafts, 138,043 shp / 102,980 Kw = 30.00 kts
Range 10,000nm at 15.00 kts

Complement:
1,305 - 1,696

Cost:
£12.419 million / $49.675 million

Distribution of weights at normal displacement:
Armament: 1,531 tons, 4.3 %
Armour: 11,839 tons, 32.9 %
Belts: 3,907 tons, 10.9 %, Armament: 2,802 tons, 7.8 %, Armour Deck: 4,713 tons, 13.1 %
Conning Tower: 0 tons, 0.0 %, Torpedo bulkhead: 416 tons, 1.2 %
Machinery: 4,183 tons, 11.6 %
Hull, fittings & equipment: 13,708 tons, 38.1 %
Fuel, ammunition & stores: 4,577 tons, 12.7 %
Miscellaneous weights: 100 tons, 0.3 %

Metacentric height 5.9

Remarks:
Hull space for machinery, storage & compartmentation is adequate
Room for accommodation & workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform

Estimated overall survivability and seakeeping ability:
Relative margin of stability: 1.11
Shellfire needed to sink: 39,395 lbs / 17,869 Kg = 30.1 x 13.8 " / 350 mm shells
(Approx weight of penetrating shell hits needed to sink ship excluding critical hits)
Torpedoes needed to sink: 4.9
(Approx number of typical torpedo hits needed to sink ship)
Relative steadiness as gun platform: 70 %
(Average = 50 %)
Relative rocking effect from firing to beam: 0.52
Relative quality as seaboat: 1.06

Hull form characteristics:
Block coefficient: 0.582
Sharpness coefficient: 0.38
Hull speed coefficient 'M': 7.30
'Natural speed' for length: 28.06 kts
Power going to wave formation at top speed: 51 %
Trim: 66
(Maximise stabilty/flotation = 0, Maximise steadiness/seakeeping = 100)

Estimated hull characteristics & strength:
Underwater volume absorbed by magazines and engineering spaces: 89.9 %
Relative accommodation and working space: 160.1 %
(Average = 100%)
Displacement factor: 110 %
(Displacement relative to loading factors)
Relative cross-sectional hull strength: 1.01
(Structure weight / hull surface area: 182 lbs / square foot or 890 Kg / square metre)
Relative longitudinal hull strength: 1.00
(for 20.34 ft / 6.20 m average freeboard, freeboard adjustment 0.78 ft)
Relative composite hull strength: 1.00

Belt is 18° angled

official version:

Don Juan D'Austria, Iberia BB laid down 1930

Displacement:
28,589 t light; 30,264 t standard; 32,704 t normal; 34,526 t full load
Loading submergence 1,482 tons/feet

Dimensions:
787.40 ft x 98.43 ft x 26.90 ft (normal load)
240.00 m x 30.00 m x 8.20 m

Armament:
8 - 13.78" / 350 mm guns (2 Main turrets x 4 guns)
24 - 5.12" / 130 mm guns (6 2nd turrets x 4 guns)
24 - 2.24" / 57 mm AA guns
32 - 1.38" / 35 mm guns
Weight of broadside 12,252 lbs / 5,557 kg

Armour:
Belt 12.99" / 330 mm, ends unarmoured
Belts cover 97 % of normal area
Main turrets 12.99" / 330 mm, 2nd turrets 3.94" / 100 mm
AA gun shields 1.57" / 40 mm, Light gun shields 0.79" / 20 mm
Armour deck 3.94" / 100 mm, Torpedo bulkhead 0.79" / 20 mm

Machinery:
Oil fired boilers, steam turbines plus diesel motors,
Electric cruising motors plus geared drives, 3 shafts, 128,678 shp / 95,994 Kw = 30.00 kts
Range 9,000nm at 15.00 kts

Complement:
1,215 - 1,580

Cost:
£11.847 million / $47.388 million

Distribution of weights at normal displacement:
Armament: 1,531 tons, 4.7 %
Armour: 9,816 tons, 30.0 %
Belts: 3,224 tons, 9.9 %, Armament: 2,415 tons, 7.4 %, Armour Deck: 3,777 tons, 11.5 %
Conning Tower: 0 tons, 0.0 %, Torpedo bulkhead: 401 tons, 1.2 %
Machinery: 3,899 tons, 11.9 %
Hull, fittings & equipment: 13,242 tons, 40.5 %
Fuel, ammunition & stores: 4,115 tons, 12.6 %
Miscellaneous weights: 100 tons, 0.3 %

Metacentric height 6.1

Remarks:
Hull space for machinery, storage & compartmentation is adequate
Room for accommodation & workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform

Estimated overall survivability and seakeeping ability:
Relative margin of stability: 1.13
Shellfire needed to sink: 35,118 lbs / 15,929 Kg = 26.8 x 13.8 " / 350 mm shells
(Approx weight of penetrating shell hits needed to sink ship excluding critical hits)
Torpedoes needed to sink: 4.4
(Approx number of typical torpedo hits needed to sink ship)
Relative steadiness as gun platform: 71 %
(Average = 50 %)
Relative rocking effect from firing to beam: 0.53
Relative quality as seaboat: 1.09

Hull form characteristics:
Block coefficient: 0.549
Sharpness coefficient: 0.37
Hull speed coefficient 'M': 7.53
'Natural speed' for length: 28.06 kts
Power going to wave formation at top speed: 50 %
Trim: 65
(Maximise stabilty/flotation = 0, Maximise steadiness/seakeeping = 100)

Estimated hull characteristics & strength:
Underwater volume absorbed by magazines and engineering spaces: 95.0 %
Relative accommodation and working space: 165.4 %
(Average = 100%)
Displacement factor: 109 %
(Displacement relative to loading factors)
Relative cross-sectional hull strength: 1.00
(Structure weight / hull surface area: 183 lbs / square foot or 891 Kg / square metre)
Relative longitudinal hull strength: 1.01
(for 20.34 ft / 6.20 m average freeboard, freeboard adjustment 1.15 ft)
Relative composite hull strength: 1.00

Belt is 18° angled

anybody going to spot the difference?

Those 5.1 Quads would be quite troblesome and if they are meant to be a DP mount thier turret ring size will make them useless for AA. If they are just surface guns I'd make them triple 6" turrets for more hitting power and less problems than a quad mount. Quads are good for guns above 11" but below that they don't make much sence at least in my opinion. Other than that you have a nice design there!

Don Juan D'Austria, Iberia BB laid down 1930

Displacement:
31,276 t light; 33,099 t standard; 35,939 t normal; 38,066 t full load
Loading submergence 1,541 tons/feet

Dimensions:
787.40 ft x 98.43 ft x 27.89 ft (normal load)
240.00 m x 30.00 m x 8.50 m

Armament:
8 - 14.37" / 365 mm guns (2 Main turrets x 4 guns)
18 - 5.12" / 130 mm guns (6 2nd turrets x 3 guns)
24 - 2.24" / 57 mm AA guns
32 - 1.38" / 35 mm guns
Weight of broadside 13,254 lbs / 6,012 kg

Armour:
Belt 15.75" / 400 mm, ends unarmoured
Belts cover 97 % of normal area
Main turrets 15.75" / 400 mm, 2nd turrets 3.94" / 100 mm
AA gun shields 1.57" / 40 mm, Light gun shields 0.79" / 20 mm
Armour deck 4.72" / 120 mm, Torpedo bulkhead 0.79" / 20 mm

Machinery:
Oil fired boilers, steam turbines plus diesel motors,
Electric cruising motors plus geared drives, 3 shafts, 120,888 shp / 90,182 Kw = 29.00 kts
Range 10,000nm at 15.00 kts

Complement:
1,305 - 1,696

Cost:
£12.542 million / $50.168 million

Distribution of weights at normal displacement:
Armament: 1,657 tons, 4.6 %
Armour: 11,922 tons, 33.2 %
Belts: 3,907 tons, 10.9 %, Armament: 2,886 tons, 8.0 %, Armour Deck: 4,713 tons, 13.1 %
Conning Tower: 0 tons, 0.0 %, Torpedo bulkhead: 416 tons, 1.2 %
Machinery: 3,663 tons, 10.2 %
Hull, fittings & equipment: 13,934 tons, 38.8 %
Fuel, ammunition & stores: 4,663 tons, 13.0 %
Miscellaneous weights: 100 tons, 0.3 %

Metacentric height 6.1

Remarks:
Hull space for machinery, storage & compartmentation is adequate
Room for accommodation & workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform

Estimated overall survivability and seakeeping ability:
Relative margin of stability: 1.13
Shellfire needed to sink: 40,861 lbs / 18,534 Kg = 27.5 x 14.4 " / 365 mm shells
(Approx weight of penetrating shell hits needed to sink ship excluding critical hits)
Torpedoes needed to sink: 5.1
(Approx number of typical torpedo hits needed to sink ship)
Relative steadiness as gun platform: 70 %
(Average = 50 %)
Relative rocking effect from firing to beam: 0.55
Relative quality as seaboat: 1.13

Hull form characteristics:
Block coefficient: 0.582
Sharpness coefficient: 0.38
Hull speed coefficient 'M': 7.30
'Natural speed' for length: 28.06 kts
Power going to wave formation at top speed: 49 %
Trim: 62
(Maximise stabilty/flotation = 0, Maximise steadiness/seakeeping = 100)

Estimated hull characteristics & strength:
Underwater volume absorbed by magazines and engineering spaces: 87.4 %
Relative accommodation and working space: 160.1 %
(Average = 100%)
Displacement factor: 110 %
(Displacement relative to loading factors)
Relative cross-sectional hull strength: 1.00
(Structure weight / hull surface area: 185 lbs / square foot or 905 Kg / square metre)
Relative longitudinal hull strength: 1.01
(for 20.34 ft / 6.20 m average freeboard, freeboard adjustment 0.78 ft)
Relative composite hull strength: 1.00

Belt is 18° angled

So your application of N^2 in this case is fielding a greater number of smaller vessels, rather than a lesser number of 40,000 ton ships?

which also are highly survivable. yes, that's what I figured. Before that I had thought about a "hi-lo" mix, some 40k BBs and some cruiser killers, but these seem to make more sense....

Bernhard

Quoted

Originally posted by The Rock Doctor
So your application of N^2 in this case is fielding a greater number of smaller vessels, rather than a lesser number of 40,000 ton ships?

bassically is what N-squared law says. That more ships of a lesser capability are a better choice than less ships of a better quality. However, I see a lot problems on the application of N-Squared to real world.


We'll start just by the bassic of n-squared regarding numerical advantage vs quality advantage...
a BB of 33000 tons means 7000 less than 40000. So for each 200.000 tons of battleships you get 5 40k ton ships, or 6 33k ton ships. N-Squared needs a bigger number to make a real difference. If I were to use N-squared as a tool to design my fleet, I won't go beyond 28k ships. That means that for each 200000 tons you get five 40k tonner BBs or 7 28k ships. You need at least 2 more ships to make a real difference, one won't make it.


The main problem of N^2 is that is pure theoretical work. It doesn't take in account fatalities (magazine explosions, crippling of ships with a critical hit, etc). Those Fatalities are way more probable in lesser protected and less armed ships than in better protected and armed ones. Is far more probable to get a hit that cripples, say, the machinery of a ship if you hit with a heavy shell and the target is not as well armored as you, than if you hit with a lighter shell.

Critical hits aside, N^2 works with an overly simplistic model to simulate the results. Thus, it's an useful tool to know to wether extent numerical advantages are better than quality advantages, but is NOT to predict real life battle results. N^2 doesn't take in account things as important as guns range, rate of fire, speeds, accuracy of guns, quality of damage control, design compromises, etc. All those variables are just too important in real life, so one can't place all his trust in N^2 model results

With a comparatively low number difference between the forces ,n^2 is probably not going to work in real life. If we are talking about, say, 10 vs 15 odds, it MAY (or may not) work. However, if we are talking about 2vs3, it most probably won't, because the lesser the numbers, the more important role quality plays. The smaller the numbers, the higher chance that real life issues not taken in account in the N^2 theory (the most prominent one being ,as I said, that N^2 doesn't work with critic hits) will mean your force's defeat.



In this game, treaty limits and building capability means that no nation is going to have a BIG advantage in numbers unless you start with a great lead in that department. And none of the playable nations own that advantage. So, to base a battlefleet on N^2 theories will probably won't work. In this particular case, I'm pretty sure it WON'T work for the reasons listed...the most important one being the small number advantage you win just by saving 7k tons per ship, but the rest also are taken in account. Weather, tactical situation, gun ranges, armor qualities, damage control, etc.


Just to put an example, based on N^2 law, the Jutland battle should've meant the definitive crippling of the HSF...yet we know the result was a completely different one.

Based on N^2, too, Denmark Straits should've been a resounding british victory...however we also see how this result wasn't by far the one predicted by the mathematical model. Same can be applied to the Scharnhorst&Gneisenau encounter vs Renown in 1940, or the Guadalcanal naval battles.

N^2 is a good mathematical model and helpful in discerning to which point you can trust in numbers over quality. However is not by far definitive, and not directly appliable to Real Life. Taking N^2 in mind as one of many factors involved in naval matters is good. But basing your battlefleet composition and theoric work on it, is rather not.

The big problem I notice with the N^2 rule is the uncertainties of war. For example you used the denmark straights action as an example. In theory the British should have won, but due to P.O.W. being new and having a poor go with her guns later in the action, Hood being on the recieving end of possibly the most unlucky hit of the war, and the fact that due to poor comunication the British cruisers could not join the battle in time the british lost. When the Bismarck was finally sunk I think the N^2 law worked as all the uncertainties of war worked in the Brits favor so in the hunt for the Bismark the N^2 law was 1 for 2. The battle of the river plate is another classic example. Three british cruisers of lesser quality tactically defeated 1 of far greater quality, allthough again the uncertainties of war had a slight hand in the outcome.

Hmm, but with the Treaty limitations the whole thing means that (theoretically and if I didn't have the Potugal class) I could build 12 30kton BBs or 9 40 kton ones. The ships I posted would be declared as 30 kton. Smaller and I will not get the advantages of "ships need to stay afloat" nor reasonably hard-hitting guns. I do not think that 34 cm is a good idea in a world of 400 mm armour.

cheers

Bernhard

I'd agree that N^2 may not work well for navies with limited numbers of capital ships at a gross scale. However, the guy with 7 - 30,000 t ships isn't going to go after all five of the other guy's 40,000 t ships. He's going to look for ways to acheive local superiority, which is what I Jutland started out as.

So 3 - 30kt ships will pre-occupy (not necessarily engage) 3 - 40 kt, and be at a slight disadvantage (90:120) in doing so. Meanwhile, the other 4 30 kt ships are ganging up on the 2 40kt ships (120:80). The guy with 30 kt ships wins even if ship losses are equal - because then it's 6 x 30 to 4 x 40.

And while it's true that a smaller ship may be more susceptible to catastrophic failures/events, the consequences aren't as severe as if it happens to the bigger ship. A larger force has more depth to it, and can afford the loss of a single unit.

Moving down to smaller ships, I think that N^2 could prove more applicable to cruiser and destroyers in our context. I think some of us have been applying N^2 without saying so. There are more of them, they aren't nearly as well protected, and the consequences of a catastrophic event - torpedo hit, aerial bomb hit - are far more devastating.

N^2 could also apply to our ongoing quadruple/twin turret debate. If firepower is equal, do four twins outlast two quads? If Warspite and Richelieu meet, Warspite has to hit two specific areas of Richelieu (her turrets) to achieve a soft kill. Richelieu has to hit four specific areas of Warspite to acheive a soft kill - and each of those areas is considerably smaller than what Warspite is shooting at. N^2 would suggest that Warspite is favored here.

Lord Arpad: bear in mind that 400 mm armor is starting to be a bit redundant against 15" and smaller shells, especially when inclined armor makes an appearance. A lot of 40 kt ships are, in my mind, over-protected.

J

Couple of things about N^2 and historical battles.


First, the battle of the River Plate. That is again a show that N^2 doesn't work in real life as it works in an ideal mathematical world. n^2 dictated that such an engagement should've finished in a total german defeat, however in RL the KM Graf Spee was not in danger of sinking (by far), while the HMS Exeter was very nearly disabled, and the Achilles had half its main battery out of action. Had the battle gone on, I see Exeter going under, and the Ajax and Achilles withdrawing to a shadowing position to allow for a later interception by heavier units.


Bismarck's Final Battle saw worse odds than what you seem to think. 2vs1 was not the case, that for sure, remember , that battle was also fought by RN cruisers, that helped quite a bit in reducing the Bismack to metallic rubble. Also, the german ship was seriously damaged before the action started, so making the odds even worse for the germans.


finally, I think that the most prominent evidence that N^2 doesn't work was the Jutland Battle. Germans faced terrible odds against them (28 dreadnoughts vs 16 dreadnoughts and 6 pre-dreadnoughts and 8 Battlecruisers vs 5 Battlecruisers. And similar or worse odds in cruisers and torpedo boats.).N^2 says that such a battle will mean a crushing defeat for the smaller force, however as we know the battle was a german victory (phyrric as it was because it didn't give the germans the strategic initiative, and the latter effects of that battle meant that the HSF never would fight the Grand Fleet again).




Bernhard, the problem I foresee with your battlefleet is not that it can't achieve the numbers required for N^2 to work (even if you declare them under their real tonnage )...the problem is that N^2 may, or may not work even with the numbers required. It's simply a mathematical model in an idealistic mathematical world. It's conclussions can't be ignored, yet they can't be used as an immovable fact, as a proven factor, because they ain't such.

Quoted

Lord Arpad: bear in mind that 400 mm armor is starting to be a bit redundant against 15" and smaller shells, especially when inclined armor makes an appearance. A lot of 40 kt ships are, in my mind, over-protected.

Hmm, but (and yes I know that this is hindsight): Bismarck's side armour (350 mm) was pierced repeatedly by KGV and Rodney. Now this may be partly due to the scaling effects of Wh Armour but I am still of the opinion that armour that does not protect is useless. A turret than can be taken out with a single hit might as well not be armoured. similar stuff goes for belt armour.

Quoted

yet they can't be used as an immovable fact, as a proven factor, because they ain't such

'course not. if we analyse the individual battles:

River plate: no RN ship even remotely matched Graf Spee, although she was not all that well armoured.

Denmark strait: superior German gun control vs. a Brit BC (who's reliability as a design family had been conclusively proven by Jutland) and a new ship.

Jutland: German tactical victory and strategic defeat. Jellicoe outmaneuvered us all the time and we only got saved by superior drill and the high survivability of our ships (although we did loose a a BB). Flatly oe can prove whatever one wants with that action.

Bismarcks final battle: B already wounded, and majorly outnumbered.

As to the quad/twin debate: I ususally use my freed up weight form the quads for better armour. so the question gets rephrased to: 2 less suvivable turrets on a less survivable platform vs. 1 more survivable turret on a more survivable platform.

cheers

Bernhard

Quoted

Originally posted by LordArpad
'course not. if we analyse the individual battles:

River plate: no RN ship even remotely matched Graf Spee, although she was not all that well armoured.

Denmark strait: superior German gun control vs. a Brit BC (who's reliability as a design family had been conclusively proven by Jutland) and a new ship.

Jutland: German tactical victory and strategic defeat. Jellicoe outmaneuvered us all the time and we only got saved by superior drill and the high survivability of our ships (although we did loose a a BB). Flatly oe can prove whatever one wants with that action.

Bismarcks final battle: B already wounded, and majorly outnumbered.

Some notes to add to yours...

about river plate, the Graf Spee was not enough armored even to stand 6' hits .

About Denmark Straits, I agree with the great german gunnery, however, I do not about the Hood itself. The Hood was a complete departure from the WWI BC concept. It was ,rather than a battlecruiser, a fast battleship. If you see the armor on the Hood you see that ,apart of its deck armor (that was intended to be modified in the 1939 modernization that never was to happen), the ship itself was quite well armored. The only true BCs in service in 1941 were the japanese Kongos and the british Renowns. HMS Hood had far better protecion than those ships, and far better protection than WWI BCs. HMS Hood was a post-jutland ship, modified while in construction to apply the lessons learnt during that battle...no, IMHO they were not that badly protected ships as you seem to think.

The hit that blew up the Hood was one with a very, very slim chance to happen given the armor of the ship and the ranges involved in the battle. Literallly, was one shot in a million. Call it "golden twinkee", call it "low chance shot", or call it "luck"...the main thing that hit shows is that N^2 doesn't apply in real life because those kind of hits aren't taken in account .


About Jutland, yes, there was some superb tactical moves at the start of the battlefleet confrontation itself (the deployement of the Grand Fleet in line to port instead to starboard). However, I think Jellicoe did very bad decisions after the first combat turn by Scheer. His conservativeness was crucial in letting the HSF flee away with a victory, when, had he pushed the things a bit more he could've won a resounding victory. And his later decision not to cover the Horns' reef path was terrible.


However, we see again N^2 doesn't apply because all those factors you mentioned (weather, tactical decisions, british cordite, low quality british shells,german magazines' flashtight doors closed when british were open, etc) aren't taken in account. There are, really, a lot of lessons and conclussions to reach after a proper study of that battle. However, the one lesson that can't be denied is that N^2 was proven to be directly unappliable to real life.


Finally, no matter how well protected a ship can be, you can't avoid being in risk of getting some hard hits. PoW's hits on Bismarck, for instance, couldn't be protected by any kind of armor. The hit in the bows was unstoppable because heavy armor can't be put there, and the flooding hit amidships happened under the main belt, on the superior side of the TDS. So either you put a very wide belt on board (at the cost of weight, and narrowing the TDS), or you leave the TDS as it is (thus risking diving shells causing serious flooding into the vitals,as it happened with the Bismarck). also, you can never properly protect some critical parts of the ship that if hit will cause a serious drawbacks (torpedo hits on the stern, main fire directors, etc)...

I do think your design is very well balanced, and a great achievement given the limited displacement you used. However, I'm not convinced of it's ability to stand battle damage, aswell as it's ability to win a battle against a somewhat smaller fleet with similar protection and much better weapons. Of course, I can be proven wrong, who knows . That's just my view on the matter and I can be completely wrong

Quoted

The Hood was a complete departure from the WWI BC concept. It was ,rather than a battlecruiser, a fast battleship. If you see the armor on the Hood you see that ,apart of its deck armor (that was intended to be modified in the 1939 modernization that never was to happen), the ship itself was quite well armored.

hmm. yes and no. the crucial lesson from Jutland re: armour was "protect your magazines better, especially from plunging fire" and that was exactl what was not done in Hood's case. IMHO all that "fast Battleship" argument is windowdressing for the fact that they did _not_ approach one of the major weaknesses of the design. IIRC one of the BCs at Jutland was destroyed by a rather similar hit ... Also they did _not_ change their cordite.

As to Spee: I know she was totally underarmoured. I have a feeling that the brits were so busy dodging shells that would sink them directly that they didn't shoot straight. Also again: superior German fire control.

the prob with n^2 is the good old "ceteres paribus". But since all the other things differ as well, it ends up being next to useless.

cheers

Bernhard

Quoted

Originally posted by LordArpad

hmm. yes and no. the crucial lesson from Jutland re: armour was "protect your magazines better, especially from plunging fire" and that was exactl what was not done in Hood's case. IMHO all that "fast Battleship" argument is windowdressing for the fact that they did _not_ approach one of the major weaknesses of the design. IIRC one of the BCs at Jutland was destroyed by a rather similar hit ... Also they did _not_ change their cordite.

have to disagree completely. Queen Mary and Indefatigable (I'm not sure about invincible, but I think was the same story) were well under 15000 yards from the german BCs when they blew up. At those distances deck armor still doesn't play any significant part in protecting anything. Those ships were sunk because they were fatally underarmoured from the start, not because it's deck armor was weak. At that moment all ships' deck armor was very thin, and that remained without change for some years to come.


the Hood saw it's armor improved significantly during its construction, and it's cordite management improved.For 1939 standards it's deck armor was indeed very thin, but that was the modernization was intended for. And in the battle vs the Bismarck, the fatal hit had little to do with better or worse deck armor. The HMS Hood's maganizes were well protected for hits at that range. There's still debate on how did she blew up because a direct penetration of the 4' or 15' magazines was not just unlikely, but almost impossible given the ranges involved, the angle of the ship compared with the bismarck, and the german 380mm shell performance itself.

And, during WWII, british cordite was way more stable than in WWI. It indeed changed, if not in nature, yes in stability when facing an accidental ignition.



`

Quoted

As to Spee: I know she was totally underarmoured. I have a feeling that the brits were so busy dodging shells that would sink them directly that they didn't shoot straight. Also again: superior German fire control.

No, not really. British gunnery during Jutland was very good indeed, as it was seen during the battlefleet confrontation. During the BCs Run to the South, and later Run to the North, the germans had a better chance of shooting, as the british ships were highlighted against the brighter sky behind the british battlecruisers (the german BCs were on the east and the british on the west), while the british had serious trouble in seeing the enemy at all. British gunnery at this stage can't be really measured given the bad lightning conditions they had to face at that moment.

During the battlefleet confrontation, Scheer saw his T crossed when the Grand fleet deployed towards his eastern side. From then onwards the German ships weren't able to engage the major part of the british battlefleet because, while they were perfectly seen from the british line, they couldn't see the british themselfs. At that point the british gunnery peaked it's efficience, as both Scheer and Hipper noted in their memories. On that stage of the battle, had the british shells been of any efficience, Lutzow, Seydlitz, probably Derrflinger and most probably some dreadnoughts too, would've gone under at that moment. As it was, british shells kept being shattered on non-perpendicular hits and the germans saved the day although they received a serious beating.

From there onwards bad decisions by jellicoe first, mixed later with some luck and the magnificent night fighting training the germans had compared with the english, decided the battle would end like it did.

only that I was talking about the River Plate. That the gunnery of the Grand Fleet was good, I know.

I was trying to understand why Graf Spee was as undamaged as she was.

but back to n^2: I really think as with all laws it only works if all other things are equal, and they never are.

thanks for quite a few enlightening details :-)

Bernhard

Quoted

Originally posted by LordArpad
only that I was talking about the River Plate. That the gunnery of the Grand Fleet was good, I know.

I was trying to understand why Graf Spee was as undamaged as she was.

damn...Instead of "Spee's" I read "Scheer's". I thought you were talking about Jutland there.


my opinion on why the Graf Spee didn't receive any worse hits than the ones she received is that she got lucky. For instance, looking at the turret armor one notices that it was vulnerable to most hits to be received by the british ships. One penetrating hit in the turret and you get half the main battery of the german ship out of action...not a good prospect ,for sure. It just happened that no 6 or 8 inch shell hit neither of both turrets.

I won't say that british gunnery was all that bad in that encounter. In fact German gunnery wasn't that great either, given the percentage of hits obtained (not sure about the real number, I recall reading somewhere that the % of german hits were around the 3-4%, wich ain't that good. however I'm not sure about the fiability of that number)

About the british gunnery, the Graf Spee's damage status when arrived at Montevideo was quite serious, the ship was in a quite sorry state. I do think the 6' cruisers put up a decent fight and gunnery no matter they didn't achieve any serious hit on their own (well, there's that pic of the big hole on the side of the Graf Spee, but that was the most serious hit the british light cruisers got on the german panzerschiffe).

About the Exeter, yes, I also think she was too much worried trying to avoid being hit to get a good shooting against the german warship.
But one can't blame them for that , those 11' guns were fearsome when used against a cruiser, and in fact they did cripple the british ship. Had the shell storm gone on, I'm sure she won't have survived for long.

As I understand it: The theory of N-squarred is meant to explain why a party with superior numbers holds an advantage against someone with inferior numbers.

It doesn´t include anything about quality vs. quantity. It simply explains on a mathematical level why a party with a higher number of ships will win against one with a lower number given that all ships are equal and that the chance for a "lucky shot" is also equal for both sides.
So, ceterus paribus (as LA pointed out), the only variable here is the number of vessels.

These are the basics of N^2. The way it is used in most cases is wrong because the ships of both sides are not equal. However, it can be used if the differences are marginal. The problem then is the definition of "marginal". A difference of 7000ts between single capital ships build under the CT surely is not. Thus N^2 can´t be used by here.

As for some other things mentioned in this thread:

a) The GRAF SPEE, being the last of the Panzerschiffe, was not as poorly armoured as some of you seem to think (just compare her to CAs or CLs of other nations build during the late 20s/early 30s). In fact, against 6" shells she was well protected. It is a myth that you need 6" plates to defeat 6" shells. An 80mm belt (inclined) and 140mm faceplates can do the trick as well.

What is true on the other hand is that she indeed wouldn´t have been able to resist many 8" projectiles but even then those shells had to hit the right areas (read vitals) to cause any significant damage and most often this is exactely what does not happen during gun fights - one of the main reasons why I also think most of the CT-designs are over-protected, especially in the cruiser categories.

By the end of her last battle, GS was very far from being even in danger of sinking. She did not receive what would normally be called a devasting hit. No gun or rangefinder was destroyed, her fighting and seagoing capabilities not influenced. Being low on ammo, having lost her bakery and pantries and thus not being able to fed her crew (even thought it might have been possible in an emergency in some way) and - most serious - having lost her capability to filter/clean her oil for the diesels made her head for a port where she was finally blocked (much like SMS KÖNIGSBERG in WW1, btw).

The unique circumstances she had to face being a german raider without any friendly base around was what doomed her, not the british shells. This, and british intelligence.

Had GS been closer to a friendly port (say in the North Sea, Baltic or Med - maybe even Parcific) she would have survived most likely.

b) Somebody stated that BISMARCKs 350mm belt was penetrated time and again. This statement is severly flawed. First of all BS had a 320mm belt (the Twins had 350mm) and second the latest examination of her wreck revealed that less than a handful of shells sucessfully penetrated her belt - and those must have been fired at very close ranges. Browse the BISMARCK-Forum at http://f16.parsimony.net/forum26300/ for more information.

Regards,

HoOmAn

I'm still not fully convinced about the level of damage that Bismarck took from shellfire and torpedo damage. Very little underwater footage was shown of the entire hull still above the mud where she sank. The commom statement made about bismarcks torpedo bulkhead is that it was not penetrated and therefore kept the ship from sinking at the hands of the british. Just because the bulkheads are not penetrated dosn't mean that many little leaks were created. That would lead to serious progressive flooding if left un-checked. I'm also not convinced that only two shells penetrated the main belt as I have yet to see the intire hull. Allthough I'm not saying it isn't possible I would like to see more footage than just two sections of the main belt before I come to a conclusion. All this aside it dosn't take away from the bravery shown on both sides in this battle.