Dreadnaught (Texas) vs. Most Modern (Iowa) Battleships
- Thread starter Jeff Head
- Start date
For current USN CVN/LHA/LHD see there
https://www.sinodefenceforum.com/todays-us-navy-photos-videos.t5379/page-195#post-362909
https://www.sinodefenceforum.com/todays-us-navy-photos-videos.t5379/page-195#post-362909
Jura The idiot
General
hey, Lezt! I hoped you'd appear here
I don't want to argue or nothing, but I think first we should state what designed TNT equivalent we're talking (to be withstood by underwater protection systems; as in "700 pounds - North Carolina-class")
very interesting, I read it carefully ... the older designs mentioned by that writer were probably included in "A total of 77 designs were developed during the period 1935-37, when the characteristics for the North Carolina were established." (Garzke & Dulin p. 32);
the newer designs are pretty much covered starting from p. 107
I'm looking forward to read the rest
YEs...they were all designed with a requirement to get through the Panama Canal in mind.
The Montana class was not going to be...but it was never built. The super carriers were not designed with that requirement either.
THAT is an outstanding diagram of the Iowa modernization.
I had not seen it before. Thanks, it is a keeper.
Jura The idiot
General
nobody shot back LOL so I'll finish my thoughts by going back to
I don't take issue with using the Mark I Rangekeeper or any other fire-control method of 100 years ago, but I don't believe single-gun shots applied then, I mean if you were hitting like 200 meters plus circle, would you believe your correction for the next shot? I'll give one more example:
Russian (Tzarist) Navy according to the so called 1915 Plan would have obtained Battleships with 16" guns in three quadruple turrets (yes, 12*16", to outshoot anything which would enter the Baltic Sea in 1920s; of course this was just the plan, but it's not the point here). I've read the firing procedure of Russian Battleships at that time followed some quadrilateral pattern, aiming at its four corners (and "shrinking" its sides, hopefully
with subsequent shots). With three quadruple turrets, one new Battleship could engage three targets at a time this way ("wow"), or ("even better") should be able to quickly cover the target, as the three turrets would be firing consecutively, the next one to the positions updated from results of the previous one or two -- and these one or two would be loading/aiming at that time ... but would it have worked in, say, 1920? (don't worry, the ships weren't even ordered I know I talk with the benefit of hindsight, and I'll leave it at that.
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hey, Lezt! I hoped you'd appear here
I'm looking forward to read the rest
Thanks guys, I am actually in a terrible bind here, I am flying out in the morning,
But here is my thoughts from my years of study.
1) there is no such thing as a better design, all nations and designers optimized what they had their hands on. Everything was an give or take. Yamato and Iowa was designed to resist plunging fire from ~30 km from the very steep ~80 degrees inclined belt. I don't like to classify armor to "all or nothing" or other commonly used terms. The Bismark used an older multi-layered approach to armoring where you have multiple compartments with varying layers of de-caping space and containment space.
For those of you not too familiar with shells, there are quite a few variation of shells and shots and each nation called them differently. Most armour peircing shells in WW2 are capped, and the cap is basically a very hardened piece of metal ontop of the shell to help improve penetration. armor is penetrated if the shell pushes through the armor plate or if it cracks the armor plate. what the de-caping plates are for is to crack the cap i.e. de cap, so that when the body of the shell hits the main armor plate, it will be less efficient.
What you will see in the Fuso, Richleliu and the Bismark is that there is a shallow inclined armour at around 40 degrees to help glance away the decapped shell if it passes through the main belt. i.e. they are designed to take a pounding at close range broad side. KGV practically had only a vertical main belt, although a substantially thicker one 370mm thick vs, 320mm and 307mm for the Bismark and Iowa respectively (of course bismark have a 100mm 40 deg slanted plate behind, so it is a much tougher nut to crack in a broadside.
There is also the issue of diving shells, the Japanese found prior to ww2 that shells that dive under water can still penetrate the ship under the normal armor belt. Therefore they tapered their inclined belt from the maximum thickness to a lower thickness deep under water. This is an issue really of plunging fire, which by the way, plunging fire is not actually as steep as motar fire, they are more like 30 degrees to 45 degrees.
Thus each was just optimized for the limitations they faced and their expected battle to fight. This is what I find the most amazing about battleships and that is the amount of thought that goes into them generally decades in advance. irony is, these ships rarely fight in the expected confrontation they were envisioned.
2) The Iowa, KGV, Bismark designs with the torpedo belts did have torpedo protection, but a major issue with torpedo belts is that reserve buoyancy is limited which means a very fast reduction of speed when taking torpedo hits. Bismark was slowed from 30 knots to 16 knots, POW was slowed from 28 knots to 15 knots. this is due to the counter flooding required to keep the ship on an even keel. The increase in draft due to the flooding and counter flooding, made the ship hydro dynamically less efficient. Torpedo budges provided more reserve buoyancy but they produced more drag. The Fuso class received budges which kept them afloat even after fuso was blown into two; but from the original design of 22.5 knots with 40,000 SHP, post refit with the bulges, she made 24.5 knots with 78,000 SHP. She probably would do 28-29 knots without the bulges.
3) Japan really picked a bad time to start a naval war with the USA. the USA have just completed 4 fairly new battleships, BB55 to BB59 was built before the war, BB60-64 would be finished in the war. Japan had only finished 1X yamato, prior to dec 7th 1941.
Quantity have always a quality of its own. We can argue every capital ship of the germany navy built post ww1 is 1 on 1 better than anything the US/UK/Japan built.
the secondaries of US battleships, the famous 5" / 38 is actually quite a poor surface action weapon. It is a terrific AA weapon, but it only shoots out to around 16 km; the british 5-1/4" shoots to 22 km, the german 15cm is also 22km, while the japanese 14cm on the older battleships (fuso, nagato, etc) can shoot to 20 km and the 15.5cm on the yamato can do longer. The bismark and yamato had a layered defense, with a tertiary battery of 10.5cm and 127mm respectively. (the 10.5 can shoot to 20 km and is an amazing piece of kit with 3 axis stabilization, automatic fuse setting just like the US 5"). Thus there is a vulnerability zone for US battleships against FAC like Eboats, MAS, PT; which didn't turn out to be a problem as the US had sufficient destroyers and cruisers to screen the BBs.
4) Japanese fixation on the battleline is their downfall, they needed their crusiers to be able to fight in a battleline. i.e. they needed the 8 inch guns to lob shells 20-25 km at enemy BB in a battle line and eat up salvos (hopefully misses). that made their cruiser fleet somewhat top heavy and unsuitable for close combat where the 6" with its much higher ROF will deal a lot more damage and hits. 6" and 8" gun damage potential is similar.
That is also a reason I believe that they had renamed their batttle cruisers to become battleships. i.e. Kongos. The simple fact is, the japanese battleline is actually quite weak in a standard fleet engagement. The US standards or the QE of the royal navy would easily tear them apart.
5) fire control is not that different and duplicity is paramount. fire control is fairly comparable between nations. The radar advances of the allies is not as game changing as popular media depicts. This is partly due to the weapon that they were firing were whole fully inaccurate compared to the fire control system.
if you had the range and bearing, all battleship hit quite well at around 2-5% straddle rate; which is also to say, German and Japanese radar sets did the job. the issue thou, is duplicity, British BB used the turret range finders to range and shoot, which proved an issue when the KGV was sailing into the waves and spaying her optics; her secondary optics on the bridge is has a small base length and she did not range properly untill she turnned away from bismark and away from the waves. Likewise, the radar sets on bismark was taken out early on, and therefore didn't play much of a role in the battle.
American BBs have the most automated heading, range, bearing fire control system. the japanese have a team of men to input the data into a mechancial clock. the germans and brits are inbetween. A case is generally argued that automated is better, which is likely true, but i would also say that all of the systems pretty much did their job. it is a case of, you can generate a firing solution, it might not be correct, but even if it is, you can't really guarantee to place your shells at that point.
This brings back to my original comment on armor layout, why design for plunging long range fire, when the big hits will mainly be in close range? Hood blew up, yeah. its more of a fluke. but then again, there are such a finite number of battleships/capital ships that we can't really draw any meaningful statistical conclusions.
I think this is simply a question of HEAT, single man portable AT HEAT can pen easily 1200 mm of armor, a tandem one or a larger one can pen easily pen 2000 mm of armor. the only question is putting the bursting charge in tandem to the HEAT round. This has already been done for small anti submarine torpedos.I'm not sure I understand the question, but if you asked
- if the US AShMs were able to penetrate the belt armor of 12.1" (310 mm), I'd answer: I don't think so
- about firing 16"/18" shells to achieve this penetration, I'd speculate about 25/30 km distance max. if the target was perpendicular to you (and assuming your APC shell is good
Torpedos are another very big can of worms, its a question of explosive force and duration of pulse. Torpex explosive in british torpedoes is extended pulse (later exported to the US mid war) is therefore more powerful than equivilent weight of TNT (50% to 100% more effective) although the explosive forces is similar. Hexanite used by the germans are slightly more powerful than TNT and the japanese are around 5-10% better than TNT.
Bismark's TDS is supposed to be tested against 300 kg of Hexanite, but I havnt seen the test records.
In anycase, 21" torpedos, and japanese 18" torpedoes carried close to 1000 lb of explosive at the end of the war. the last german torpedos are designed to be proximity detonated under the keel (where triple and double bottom will not do much good even thou the warhead is 400 lb or so) i.e. TDS become obsolete. This is also pointing back at the Iowas 5"/38 secondaries; had the japanese utilizes more FAC in the Philippine seas, their small radar evasive size, very good maneuverability steaming at 45 knots with type 93 long lances that will travel at 50 knots to 20 km, or at 40 knots to 32 km, will prove very challenging for the secondaries to handle if it could only shoot to 16 km. imagine 10 FAC each launching a spread of 4 torpedo from all directions.
Jura The idiot
General
hope you had a good flight, and you'll soon be back here
I feel I'll read them more than just twice I've done so far.
Would you also comment on
- Japanese heavy (14" -- 18") APC shells optimized for undewater hits (it's embarrassing but I don't understand their description in the leftmost column of p. 175 of Campbel's WW2 Naval Weapons :-( one of the problems is I've never seen them!
- Italian Battleships
hah! that's what I had in mind while ranting
https://www.sinodefenceforum.com/dr...ern-iowa-battleships.t7857/page-5#post-363418