Best quote I’ve seen in a minute on these forums.
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Is this for in-game as I read in a book that IRL it was closer to 17000 yd on the KGV against the 15" 1,938lb projectile though i’m not sure which one, but surely the 6crh cap wouldn’t make 8000 yd’s difference?
The calculation here was based on the actual firing trial after the WW2 against armour plates removed from scrapped HMS Rodney (ADM 281/40). The minimum velocity required for penetrating 14" armour with 30° angle of attack for the 15" APC ranged between 1450~>1500ft/s depending on manufacturer (FYI at 26kyds the 15" 6crh fired with worn barrels would have 28° angle of descent and 1450ft/s remained velocity). As far as I know some sources use USN empirical formula to estimate the performance of the WW2 UK 15" and one have to take a huge grain of salt on those. In fact, the improved version of 15" APC was produced only for a limited number. Post war DNO also discussed about the existing inventory of 15" APC and they decided not mass produce the improved version of 15" projectiles as for obvious reason the era of battleships had gone and the high performance was no longer needed. So in general the majority of 15" shells used by British ships during the WW2 and after are unlikely to have such performance anyway.
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Yeah improved APC was limited to something like 60 rounds per ship IIRC.
I’ll take your word for the calculations as to be honest, I don’t want to even try and run them myself i’m sure you’ve done your due diligence.
But if i’m not mistaken Nelson/Rodney use Vicker’s Cemented Armour, whereas KGV used British Cemented armour with 33% face hardening.
Garzke & Dulin’s “Allied BB’s of WW2” gives an immunity zone of 17,200 yd. Rather than 25,500, though this could be for a 4 crh and not the 6 crh MK.XVIIb
Also its the source for the ‘25% more effective than CA’ though I don’t believe it will contribute more than a secondary source in-game (plus such differences slightly irritatingly aren’t modelled).
I do not want to make comments on Garzke & Dulin due to lack of explanation of their method of calculations. In addition, I would take a large grain of salt on the statements of quality superiority of British Cemented Armour. ADM 281/40 explicitly stated an conclusion that the armour plates used on Rodney in 1923 was of no significant difference compared to the modern cemented armour except the consistency of quality:
Spoiler
Besides, Nathan Okun’s FACEHARD programme also gives a similar result to the firing trials in ADM 281/40:
There’s no way that KGV would be immune to the 15" 6crh down to 17kyds without heading angle.
For my own amusement I’ve done a calculation of the minimum immunity range of side protection of WW2 battleships against 15" 6crh Standard Charge, don’t take it too seriously tho:
I. Yamato (410mm@20°) - 14100 yd
II. Littorio (70mm@11°+280mm@11°, successful de-capping) - 19000 yd
III. Iowa (38mm+307mm@19°) - 20000 yd
III. South Dakota (32mm + 310mm@19°) - 20000 yd
III. Bismarck (320mm + 110mm@68°) - 20000 yd
VI. Richelieu (10mm + 327mm@15°) - 21000 yd
VII. North Carolina (305mm@15°) - 22500 yd
VIII. Littorio (70mm@11°+280mm@11°, unsuccessful de-capping) - 24000 yd
IX. King George V (349mm) - 25500 yd
X. Bismarck (320mm) - 28000 yd
This was calculated using the USN empirical formula, manually adjusted according to the trial results from ADM 281/40
By the way, my calculation of Bismarck’s immunity range of side protection (320mm armour belt + 110mm turtleback) was very close to the Kriegsmarine’s estimate in GKdos 100, where the Germans estimated the minimum immunity range against British 15"/42 to be about 21km vs. 20kyd in my calculation.
I was also impressed by how crucial the functionality of the de-capping system was in the case of the Littorio. It makes the Italian design either the second best or one of the worst, depending solely on whether the incoming shell was de-capped. Unfortunately, de-capping was a rather unpredictable phenomenon that various navies had looked into but didn’t come to a common understanding. The British, for example, believed that a 1-inch plate was sufficient to decap a 9.2-inch shell, while the Germans’ experiments showed that even a 100mm plate was insufficient to decap a 38cm shell.
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For naval RB I always set them for 4m deep, since they dont restock outside control zones, I only use them against big and/or slow targets.
It can be explained by the fact that the first torpedo will have been stopped by the anti-torp bulge. The second will have detonated against the side of the hull, absorbed mostly by the fuel tanks and mostly stopped by the 45mm wall of armour behind them. It makes perfect sense considering it’s armour layout. Even if a breach was made it would possibly be small which would be repairable. However the structural integrity of the middle section would have been worse. If you ever use torps against WW1 Dreadnoughts you will easily find many will survive 2-4 torp hits into the side because of the protection the bulge and coal bunkers produce.
This is actually why i wish War Thunder naval had a more advanced buoyancy system to actually reflect this. Right now, all that matters is magazine sniping and thats something German WW2 BBs does a good job of preventing. If Bismark was added in Navals current state it would’ve been the most broken and most powerful ship in the game, even if Yamato was added as a counter.
However, if said Bismark now pays for being immune to magazine strikes by being really easy to flood through belt pens. Thats a gameplay dynamic that’ll fix a lot of problems and we dont have to witness another German battleship that can absorb the firepower of every single player in the match.
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Reminder Bismark would still be hard to flood in that case due to its absurd level of comparmentalization, which is the real reason why its proportion of weight dedicated to armor is so high:
We’re talking over 500 compartments, armored to varying degree’s, many of which are watertight.
The reason the Scharn is so well protected in WT is
- The ranges involved
- Repair mechanics in WT allow ships to repair things they could not repair irl, which sways the advantage towards being able to soak damage rather than prevent it, and unless the entire games damage mechanics are completely reworked, this will never change.
When I remember correctly, both…Scharnhorst and Bismarck couldn’t be sunk by gunfire. RN scored dozens of main calibre hits, but at the end both had to be torpedoed by cruisers to actually sink. Bismarck was sunk by HMS Dorsetshire, since the disabled ship couldn’t be sunk with gunfire. For Scharnhorst Adm Fraser ordered HMS Jamaica and HMS Belfast as well as 4 destroyers to fire torpedos. He realized it won’t sink by just gunfire. Scharnhorst was sunk by 14 torpedo hits.
This buoyancy theory lacks historic evidence. Just look at the technical sketches. Both ship classes were extremly compartmentalized. Were talking about hundrets of compartments. Buoyancy wasn’t just connected to the citadel.
They were already sinking from gunfire if they couldn’t get back to port in-time. Torpedoes just sped up the process and allowed the British to get close enough to actually catch them and pepper them with more gunfire. Bismarck for example only 1 torpedo is noted as causing significant damage and that was to the propellor shafts leaving the ship unmaneuverable. No mention of flooding.
But when the cruisers attacked the next day she is noted as having a heavy list on the side to which she receive gunfire.
The ships have poor reserve buyouncy as do all post-war German Dreadnoughts , which is supported historically, yes they are well compartmentalised but what happens when you for example, break those compartments…
The theory of buoyancy needs no historical evidence, it’s elementary physics. Since the ceiling of the turtleback is below the waterline when loaded, this means that the citadel doesn’t contain any effective volume to contribute to the ship’s reserve buoyancy, as good old Archimedes already told us that any volume that displaces water already contributes to the ship’s buoyancy. The very low citadel protection deck also means that the volume of the citadel is rather limited, which is not capable of keeping the ship afloat when all other volumes are flooded, as in typical all-or-nothing designs. The turtleback also exacerbates the free surface effect, making it easier for the ship to lose stability and capsize. Compartmentalisation really isn’t something to be complimented on - what’s the point when the ship’s protection can be easily penetrated by contemporary guns at literally any range? It doesn’t really change anything other than slowing down the sinking process.
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Apologies this is unrelated to your comment but do you know why Kronshtadt has the 305mm guns rather than the 3x2 German 38cm guns of the design to which she was laid down?
(modification and order of turrets made in August 1938, ships laid down intended September actual November).
No idea, developers chose anything as they wish :)
But I would strongly doubt she’d be better to have 38cm guns. The 38cm SK C/34, along with the old German 38cm, the British 15" and Japanese 41cm shares the worst accuracy in the game. I’d rather have the 305mm laser guns.
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Out of curiousity, do you have any proof the ceiling of the turtleback is below water? Thr pic of the armor scheme above has it slightly above the waterline…
Haha, I am not advocating for a backhanded ‘buff’ for Kronshtadt, she is well balanced now.
I am more interested in developer precedent, the devs have gone with her ‘final’ design, before she was laid down on the basis that as she had been laid down, she is suitable for addition. But with her ‘final’ design which means the 305mm despite subsequent modification before she was laid to use 38cm.
I want to amend my G3 post to include an option for G3 in her ‘final’ design as this was with 16.5/45’s firing a 2,552 lbs. (1,157 kg) APC projectile at 2,425 fps (739 mps) based on Greenboy but with a 6Crh.
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Im not totally sure about this, but it feels ingame that smaller calibres with higher rof beat the big gunZ (38, 41cm) which take a millenia to reload. Bigger also means less accuracy in WT (however, thats secondary, biggest flaw is the rof.
It became evident with the Graf Spee and its 28cm main guns. First I was hyped by a cruiser sized ship with the armament of a battleship. Soon it turned out that thanks to poor rof and accuracy every 15cm armed cruiser beat that. Even some of the top destroyers have more lethal firepower (ingame) than Spee with its two 28cm turrets.
Wall of text…what I wanted to say: Upping the guns wouldn’t neccessarily mean a buff.
Yes you are right: RoF, gun-handling and penetration are all king at the moment.
When I say ‘backhanded’ I mean that the 38Cm is better than the 305mm in calibre but comes with downsides such as RoF though the 38cm could achieve 2.3 rounds per minute.
The waterline in the diagram you posted was designed WL which is lower than the waterline when fully loaded.
In Bismarck’s case, the draft will increase to 9.9m when fully loaded, which then brings the turtleback approximately level to the waterline. My apologies for the inaccurate comment but the conclusion still stands - as there’s no significant citadel volume expanding over WL (even with the designed WL) the citadel alone was incapable of keeping the ship afloat.
In addition, in most of original blueprints, (and therefore most of reproduced diagrams that can be found online) ship’s waterline was given as their unloaded conditions. For example, in Renown’s original plan the WL is even lower than the main belt:
Meanwhile in loaded condition it looks like this:
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