Best choice for 45000 tons battleship

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alecsandros
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Best choice for 45000 tons battleship

Post by alecsandros »

Gentlemen,

In the previous years much has been uncovered about the design effectiveness of the WW2 battlehsips.

With the existing knowledge, what battleship design to you consider to be optimal in WW2 oceans, considering it to have a best overall anti-battleship capability ?
This considering a 45.000 tons maximum standard displacement.

My take would be a Richelieu-type vertical armor, but constructed with Krupp armor. Total: 327mm outer belt declined at 15.5*, with 50mm thick internal slope.
Horizontal armor would be 50mm upper deck with up to 100-120mm thick MAD, both made of Wh.
Artillery - 10 x 15"/L52, in 4 turrets (2 triples and 2 doubles).
Propulsion: 28kts maximum speed on deep load of 54.000 tons.
Radars and systems: as per Tirpitz.
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Re: Best choice for 45000 tons battleship

Post by Thorsten Wahl »

Image

the germans made a evalution on paper of the french armor scheme
based on the same weight applied to armor the ballistic protection could be increased considerable by adoptiong the german scheme
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Dave Saxton
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Re: Best choice for 45000 tons battleship

Post by Dave Saxton »

alecsandros wrote: Radars and systems: as per Tirpitz.
Hmmm... Not radar and systems as per Iowa? The radars and systems on Iowa were exceptionally good.

The Tirpitz late war radar suite can match the performance of the late war American firecontrol sets in several important parameters but the American sets will have better bearing resolution and be easier to operate. The German systems are more resistant to certain types of jamming. They both have centimetric surface search sets with PPI presentation. By late war, the German sets were less likely to be knocked out by the shock of there own guns firing than the American sets, which appears to still be quite a problem on American battleships. The Americans have long range air warning sets with PPI (SK), but the 4 flak directing sets had rather mediocre performance. Tirpitz has a Wuerzburg D, and while they were not happy with the Wuerzburg, it was better than the American flak directing sets.

The British warships obviously had excellent radar systems but by 1944 they were taking some regressive steps. The world beating Type 273Q was being replaced by the lack luster Types 277/(292?) and the new 10cm Type 274, replacing Type 284M, could not the spot the fall of shot.

If you go to a hypothetical 1945 suite for Tirpitz it gets interesting.
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Re: Best choice for 45000 tons battleship

Post by alecsandros »

Thorsten Wahl wrote:the germans made a evalution on paper of the french armor scheme
based on the same weight applied to armor the ballistic protection could be increased considerable by adoptiong the german scheme
mmm...
I see 320+155mm slope on the German drawing and 320+50mm on the French drawing. How is that weight saving ?

I thought about having a ship armored against 15" gunfire out to 15km, but having decks strong enough to resist gunfire out to 30km against 16" gunfire.

In the German (Bismarck) arrangement, the probable realistic IZ was 2km for vertical attack and 24km for horizontal attack from 16" gunfire.
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Re: Best choice for 45000 tons battleship

Post by Dave Saxton »

The German system is weight efficient because the same weight of armour provides both horizontal and vertical protection.

According to Hoyer the scarps and the flat portions of the deck should ideally be all uniform thickness. The historical designs were in violation of their own rule. This was probably done to meet tighter weight restrictions and to free up some weight for the heavy middle artillery ...ect.. But with a few thousand more tons available at 45k and some changes in secondary armament, a 120mm uniform panzer deck and scarps can be obtained. This would provide both a 30km upper IZ vs low velocity 16"/45, and a superior inner IZ vs the same and high velocity guns. It would in my opinion be far superior to the French layout-and more weight efficent.

In the French layout the slopes are too steep and too thin to provide the same level of ballistic protection as the German scarp system. It's really only a plate debris barrier.

There are undesirable aspects of steeply sloped belts design, more so if internal. It protects less area and it is more vulnerable to diving shell. It fails to protect the water plane. It requires compromise to the TDS. It is much more difficult to construct and to repair. Dock yards don't like it. With a proper scarp triangle a steeply slope belt is not needed.
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.
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Re: Best choice for 45000 tons battleship

Post by alecsandros »

Ah,
of course it would be desirable to keep the heavy scarp, but with 2 extra 15" guns and the systems as per TIrpitz, the weight restriction of 45.000 tons doesn't leave much room for armor. My bet is that armor would need to be re-positioned so as to meet the weight criteria.
That's why I looked at Richelieu's veritcal armor system - a decent vertical protection...
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Re: Best choice for 45000 tons battleship

Post by ede144 »

@ alecsandros

Why 2 additional guns? It will complicate and disturb the symmetry of the turret groups. KM found it optimum to fire in groups about every 10 to 15 seconds
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Re: Best choice for 45000 tons battleship

Post by Dave Saxton »

As built, the Bismarck class was only 42,000 tons. A uniform 120 mm panzer deck seems reasonable going up to 45,000 tons. 170 mm horizontal protection and far superior vertical protection, and retaining the more ideal 4 turrets layout, compared to more conventional design, all at the same time is the result.

You also have other options such as a shorter citadel by 3x triple turrets or 2x quad turrets. But part of the German layout is a protected length of at least 70%. This is another area of design efficiency because a sacrifice of the protected length is not required to get the extra wide IZ. The longer citadel offsets a lower panzer deck height in terms of protected bouancy. Look at the French lay out; the MAD is still pretty low in the hull, but with a much shorter citadel.
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.
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Re: Best choice for 45000 tons battleship

Post by alecsandros »

ede, Dave: so you would opt for a more heavily armorred Bismarck as a 45000t design ?

My opinion is that 2 extra guns would be good in a prolonged engagement, when every extra hit counts...
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Re: Best choice for 45000 tons battleship

Post by Mostlyharmless »

My take on this is that the various navies designed their battleships to survive being hit by their own guns and shells. Bismarck and Tirpitz are optimally designed to survive hits from the German 38 cm gun at short and medium ranges. We can debate on whether Bismarck's armour would have defeated the 16 inch superheavy shell that penetrated Jean Bart's aft magazine. Clearly Bismarck would have been very vulnerable to Yamato's or even Nagato's Type 91 diving shells. Ships with internal armour belts may be vulnerable to the large charge of British shells at long range if these explode after being deflected downwards.

The German armour scheme was vulnerable to bombs. For example, Scharnhorst's main deck was penetrated at La Pallice on 24th July 1941 by 1000 lb. armour piercing bombs dropped by RAF Halifax bombers from an altitude of about 14,500 ft. Gneisenau suffered more serious damage from a single 1000 lb armour piercing bomb on the night of 26th to 27th February 1942 at Kiel but I am not sure exactly how the magazine ignited i.e. whether the main deck was penetrated or whether splinters entered via the ventilation system. Also a 1,600 lb A.P. bomb from a dive bomber penetrated Tirpitz's 80 mm main deck but did not explode on 24th August 1944.

Other armour schemes sometimes worked against bombs and sometimes failed. An example where the armour partially succeeded is the Japanese 500 kg bomb, dropped from 2,560 meters, which hit Prince of Wales amidships and was stopped by the main deck where it exploded. Although stopped by the deck, it disabled a boiler room and shut off steam to the only engine room operating. The rather strong armour on the Littorio's main turrets twice defeated bombs (Littorio in June 1942 and Roma on the night of 23rd to 24th June 1943). However, Roma was sunk was two hits from Fritz-X bombs. A bomb caused damage below Musashi's deck on 24th October 1944 but it is not clear exactly what happened.

Richelieu's armour scheme seems inefficient to my eye. If we can reduce the thickness of the 40 mm lower deck and the 50 mm scarp to 10 mm, the upper deck can become about 45 mm of armour grade steel and the outer hull perhaps 55 mm of armour. As the main armament is all forward, it should be possible to approach an enemy battleship at an angle at which that outer shell will decap even a German or Italian shell while using all the main armament. Yaw induced by 45 mm of armoured upper deck may help 150 mm of even French armour to resist an American shell. Of course, my inexpert eye cannot tell me how much that change would lower the GM or weaken the structure.
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Re: Best choice for 45000 tons battleship

Post by alecsandros »

Hi Mostlyharmless,
Mostlyharmless wrote:My take on this is that the various navies designed their battleships to survive being hit by their own guns and shells. Bismarck and Tirpitz are optimally designed to survive hits from the German 38 cm gun at short and medium ranges. We can debate on whether Bismarck's armour would have defeated the 16 inch superheavy shell that penetrated Jean Bart's aft magazine. Clearly Bismarck would have been very vulnerable to Yamato's or even Nagato's Type 91 diving shells. Ships with internal armour belts may be vulnerable to the large charge of British shells at long range if these explode after being deflected downwards.
Well, considering the horizontal perforation of the 15"/L52 gun, the Bismarck vital elements were protected against her own guns at any conceivable range.
The German armour scheme was vulnerable to bombs. For example, Scharnhorst's main deck was penetrated at La Pallice on 24th July 1941 by 1000 lb. armour piercing bombs dropped by RAF Halifax bombers from an altitude of about 14,500 ft. Gneisenau suffered more serious damage from a single 1000 lb armour piercing bomb on the night of 26th to 27th February 1942 at Kiel but I am not sure exactly how the magazine ignited i.e. whether the main deck was penetrated or whether splinters entered via the ventilation system. Also a 1,600 lb A.P. bomb from a dive bomber penetrated Tirpitz's 80 mm main deck but did not explode on 24th August 1944.
According to G&D Axis Battleships, the bomb that hit Gneisenau exploded in contact with the upper deck. Splinters were sent down an opened ventilation shaft, down into the powder magazines. 80% of the stored cartridges exploded, destroying the forward part of the ship.

All the bombs dropped over Tirpitz, Scharhorst and Gneisenau, were disabled by the double-deck system [no bomb funcitnoed correctly, except the super-heavy 5.5 tons Tall Boy bombs.]
Richelieu's armour scheme seems inefficient to my eye. If we can reduce the thickness of the 40 mm lower deck and the 50 mm scarp to 10 mm, the upper deck can become about 45 mm of armour grade steel and the outer hull perhaps 55 mm of armour. As the main armament is all forward, it should be possible to approach an enemy battleship at an angle at which that outer shell will decap even a German or Italian shell while using all the main armament. Yaw induced by 45 mm of armoured upper deck may help 150 mm of even French armour to resist an American shell. Of course, my inexpert eye cannot tell me how much that change would lower the GM or weaken the structure.
... I also find it inefficient, but my proposal was for vertical system only (327mm + 50mm). The armored decks would be 50mm upper deck + 100-120mm MAD, with no scarps. The heavy scarp would require to much weight, and there would not be any weight left for the 2 x 15" extra guns.......
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Re: Best choice for 45000 tons battleship

Post by paul.mercer »

Gentlemen,
As for the armament, could she mount 9 x 16" + suitable up-to-date anti aircraft armament and still stay within the 45000 ton limit without compromising on armour?
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Re: Best choice for 45000 tons battleship

Post by Mostlyharmless »

Dare I ask why the 45,000 ton limit? Iowa was about 48,110 tons standard displacement http://www.bb62museum.org/stats.html and there weren't many battleships of around 45,000 standard displacement to compare.

Wouldn't it be more sensible to compare by price? For example, the King George V class are alleged to cost £7,400,000 according to http://navalhistory.flixco.info/H/58285/8330/a0.htm and a contemporary newspaper describes KGV as costing £8 million in reporting the launch. I doubt if this includes the armament and KGV's armament is said to have costed £2,900,000 including all fire control instruments. Thus we have a total cost of £10.3 million or $49.44 million at the 1938 ratio of 4.8.

Bismarck may have costed RM. 196.8 million viewtopic.php?f=1&t=1169 or http://www.kbismarck.com/genedata.html. Using a 1939 2.5 RM to Dollar rate, this is $78,720,000.

Thus three KGVs against two Bismarcks would be a fair comparison (except that 2.5 RM to the Dollar may have been slightly artificial).

Similarly, North Carolina and South Dakota classes cost about $77 million each (Iowas costed more than $100 million). Thus Bismarck against North Carolina is fair but it should be four Bismarcks against three Iowas.

Finally, Yamato is quoted as costing 250,000,897 Yen by Wikipedia. Using the 3.47 Yen to the Dollar rate for 1937, this gives 72 million Dollars. Thus Yamato against Bismarck or North Carolina is again fair but really we should ask how Yamato, Musashi and Shinano would fair against Iowa and New Jersey.
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Re: Best choice for 45000 tons battleship

Post by Dave Saxton »

alecsandros wrote:ede, Dave: so you would opt for a more heavily armorred Bismarck as a 45000t design ?

My opinion is that 2 extra guns would be good in a prolonged engagement, when every extra hit counts...
The heavy scarp would require to much weight, and there would not be any weight left for the 2 x 15" extra guns.......
Yes.

If you want more than eight guns then to me it is better just to go 3x triples and have 9, and accept the trade off of a slightly shorter citadel. The slightly shorter citadel might pay for a bit heavier yet horizontal armour or for something else. The heavy scarps with matching panzer deck don't cost any more weight than a full width MAD of comparable thickness.
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.
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Re: Best choice for 45000 tons battleship

Post by pgollin »

.

I have always assumed that the H-Class battleships design was pretty much "done" as at least one was, just about, laid down - is this correct ? (This is certainly the case in regards to the 1939 Lions.)

IF so, what "improvements" from the H-class would have been worked into a modified Bismarck with an extra few thousands of tons available ?
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