Iowa Class real performance

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Karl Heidenreich
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Iowa Class real performance

Post by Karl Heidenreich »

I was thinking about this:
In theory the Iowa Class is the best all around Battleship because of his guns, it´s fire director, it´s armour, etc. If you test it´s specifications (on paper) that´s the result you get: the best BB ever.
But the Iowa was never tested in real combat against another Battleship. How do we know these "nominal" characteristics will work under fire?
Remember: Before Jutland nobody thought that the British Battlecruisers were so vulnerable until they were hit by the Germans. And nobody will thought that the Hood will blow the way she did until straddled by Bismarck in just five salvoes. What about KGV Class quadruple mounts? That´s why there is an F-1 championship every year: if the nominal characteristics of a car gives it a wining card it must be tested at the racetrack, to see if nominal is real. And it never does...
So, what happens if the armour plates present some problem? What happens if, in a BB vs. BB combat, nothing works the way it´s intended?
I wonder if Yamato (or even a Bismarck Class) catchs an Iowa with perfect weather, at some 25 K yards, smooth seas were the radar fire director would not give the Iowa a great advantage or would have it only one salvo ahead of his enemy...
We know for a fact that Bismarck gun crew could (and would) hit their enemy quite soon and with deadly accuracy: it´s a fact. But we don´t know about Iowa.

Just a thought.
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Gary
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Post by Gary »

Hi Karl.

The Iowa was a fantastic battleship but it wasnt unsinkable.
Its radar assisted fire control combined with its awesome 16" cannons made it a very dangerous opponent for any ship.
One of the other reasons that Iowa is regarded as the best BB is the fact that nothing succeeded her.

For example North Carolina was a good BB and then along came SoDak which had superior protection.
SoDak was then succeeded by Iowa which was even better.
Had the Montana's been built they would have been even better than Iowa.

I have no reason to doubt that Iowa couldnt withstand numerous heavy shell hits like other Battleships did in years gone by.
However, when torpedo'ed even she would succumb.

The British Queen Elizabeth is regarded as a successful design largely thanks to Warspite's combat record.
Iowa never got the chances that Warspite did.

Iowa could though go into a one on one encounter with any battleship in the world and have a better than even chance of winning.
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Post by Bgile »

We don't know. In any engagement like that, there are so many variables it's impossible to be sure who would win.

We do know a few things about the Iowa class because of their very long and impressive service lives. For example, I've read that when New Jersey was recommissioned for Vietnam service they considered changing her main battery fire control to a modern digital system. They decided it wasn't worth it because the old analog system was so accurate already that there was nothing to be gained by replacing it.

I believe USS Iowa (or NJ not sure) straddled a japanese destroyer on the very first salvo at 35,000 yards. It took Bismarck 3 salvoes to do that at DS at much closer range. I see no reason to think an Iowa class ship would do worse.

The guns are obviously more powerful, and would penetrate Bismarck's turret faces at just about any range.

So there are some advantages to the US ship. Does that guarantee she would beat Bismarck? No.
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Karl Heidenreich
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Post by Karl Heidenreich »

Bgile:
We do know a few things about the Iowa class because of their very long and impressive service lives. For example, I've read that when New Jersey was recommissioned for Vietnam service they considered changing her main battery fire control to a modern digital system. They decided it wasn't worth it because the old analog system was so accurate already that there was nothing to be gained by replacing it.
Reading Bgile´s post I remember that I found this some years ago and want to share it with you:
This was a story that floated among the Tin Can Navy at the end of the Vietnam War.
(Apparently the story is true and included the Barbey and not the Turner Joy)
The U.S.S. Barbey, a destroyer armed with 5-inch guns spotted a target at night off the coast of North Vietnam. Assuming it friendly a radio call was put out:
"This is the U.S.S. Barbey, please identify yourself." No response.
Signal lights were used: "This is the U.S.S. Barbey, identify yourself, friend or foe." No response.
Signal lights again, "This is the U.S.S. Barbey, identify yourself or we will commence firing!"
Answer: "This is the battleship U.S.S. New Jersey, you may fire when ready!"
:cool:
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Gary
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Post by Gary »

Hi Karl.

:D

I've heard that one before.

Here is an incident that supposedly took place around 1995 (although the US navy denied it ever happened)

ACTUAL transcript of a US naval ship with Canadian authorities off the coast of Newfoundland in October, 1995. This radio conversation was released by the Chief of Naval Operations on 10-10-95.
Americans: "Please divert your course 15 degrees to the North to avoid a collision."

Canadians: "Recommend you divert YOUR course 15 degrees to the South to avoid a collision."

Americans: "This is the captain of a US Navy ship. I say again, divert YOUR course."

Canadians: "No, I say again, you divert YOUR course."

Americans: "THIS IS THE AIRCRAFT CARRIER USS ABRAHAM LINCOLN, THE SECOND LARGEST SHIP IN THE UNITED STATES' ATLANTIC FLEET. WE ARE ACCOMPANIED BY THREE DESTROYERS, THREE CRUISERS AND NUMEROUS SUPPORT VESSELS. I DEMAND THAT YOU CHANGE YOUR COURSE 15 DEGREES NORTH. THAT'S ONE-FIVE DEGREES NORTH, OR COUNTER MEASURES WILL BE UNDERTAKEN TO ENSURE THE SAFETY OF THIS SHIP."

Canadians: "This is a lighthouse. Your call."
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marcelo_malara
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Post by marcelo_malara »

Gary, very funny but sounds fake. If the Canadians were recomending a course change because there was land in the USN ship´s way, they would say "grounding" instead of "collision".
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Karl Heidenreich
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Post by Karl Heidenreich »

Hi Gary and Marcelo,

I heard that one twice before, but in another scenario: it was a lighthouse in Spain. And after that in Hawai. So the Canadian scenario is the third, man, I believe it´s probably a hoax. But a clever one. :clap:

Best regards to both of you!
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Dave Saxton
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Re: Iowa Class real performance

Post by Dave Saxton »

Karl Heidenreich wrote: In theory the Iowa Class is the best all around Battleship because of his guns, it´s fire director, it´s armour, etc. If you test it´s specifications (on paper) that´s the result you get: the best BB ever....
We know for a fact that Bismarck gun crew could (and would) hit their enemy quite soon and with deadly accuracy: it´s a fact. But we don´t know about Iowa.
......
Well I have never accepted the popular views on these matters. let's look at some the factors beginning with it's armour scheme in less general and more specific terms, since this a technical forum.

The Iowa re-used the armour scheme of the previous South Dakota class. Was this the best armour scheme that they could have used on 48,000 ton standard displacement battleship? Was this armour layout actually better than North Carolina's? The belts are located well inside the shell plating and the armoured deck's don't extend all the way to ships sides. This armour scheme shows serious weakness, as it fails to protect any of the water plane or the wing tanks. The North Carolina set up is much better in this regard, but the reason for the change had been the fact the sloped exterior belts of NC could not protect against below the belt hits.

In the SoDak/Iowa scheme there's a tapered lower belt extension almost down to, but not all the way to, the triple bottom. Did this really provide substanially better protection against below the belt hits? I submit that it did not. The tapered lower belt actually tapers to such thickness, that at depths were it could do any good, it's weaker than the armoured holding bulkheads of many other battleships. Moreover, the lower belt extension goes right through the torpedo defense system and reduces it's effectiveness.

There's also the matter of the effectiveness of the main armour compared to that of other battleships. American WWII era Class A armour did not compare favorably to the face hardened armour of other nations, including Germany, against large caliber projectiles. It was as much as 25% less effective than British Cemented Armour. Multiply 12.2" by .75 and see how that compares? Although the main belts are sloped, this doesn't provide the boost in protection ofton claimed. Any number of period battleships has better belt protection.

The problem of armour quality wasn't limited to face hard plates either, as many examples of Class B armor also show delamination, porosity and impurity defects. Since deck penetration increases expotentially with range, any thicker horizontal armour, beyond the minimum required at a practical battle range, is wasted tonnage. Could the turrets of Iowa protect themselves against their own gun, or guns of almost equal power?

I simply don't buy the conventional wisdom that an Iowa will hit first, hit more ofton (from farther out), and hit harder, than other battleships. Too much credit is given the weight of shell and the FC system IMO.

Look at the penetration data, and the 16"/50 holds, really only a marginal edge, over other 16" shells, and even modern 15" guns. Additionally, the basic fire control systems of WWII era German battleships are every bit as good the systems used on USN BB's of the period.

True it is, that allied radars were better for a few years, but once again too much creadance is given this factor IMO.
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Post by Karl Heidenreich »

Dave Saxton:
I simply don't buy the conventional wisdom that an Iowa will hit first, hit more ofton (from farther out), and hit harder, than other battleships. Too much credit is given the weight of shell and the FC system IMO.
Neither do I. I´ve always stated that there are two main new myths about battleships:
1. That Bismarck was a faulty design, not very well built that could not sustain itself against vessels like KGV Class, Richelieu, North Dak, South Cal or Iowa.
2. That Iowa will defeat anything floating including Yamato with no sweat.

In both cases I strongly disagree. Bismarck was a very powerfull ship and so she show it in real combat, combat that could very well have ended in the sinking not only of Hood but also of PoW if Lutjens gave the the chance to Lindemann and Schneider. And Iowa, also a very powerful warship, but never tested in a BB vs. BB combat and, so, forever in the testing ground. Anyway, if in combat against Yamato I rather be on board of the Japanese vessel than trying to show how well the Radar Fire Control might work against 18" incoming shells (or Bismarck´s 15" L/47).

Best regards.
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Post by Lutscha »

Well Dave, you mention the quality problems of Class B, but it was still better than Wh. Bismarck´s shells were unlikely to penetrate a steeply inclined belt to to their inferior proofing angles.

American late war FC was better, due to radar and the ability to shoot while turning. How much better was it? By far or a little bit? We´ll have to wait for Bill Jurens´ and Brad Fischer´s paper on gunnery, maybe that will give some needed insight.

Iowa would likely have straddled BS on 35K+ on her very first salvo which BS was incapable of, wether these long range salvoes would have resulted in hits remains questionable.

Btw, the 16 inch Mk7 DID heve a much better deck penetration than the German 38cm gun, with a 1inch and 1.3 inch advantage (+ something due to better shaped noses for deck penetration) which counts for something.

Iowa´s turrets were save (against penetration at least) at certain distances, while those of BS were penetrable at all ranges.

While the strenghts and weaknesses of both ships get blown out proportion repeatedly, whether it be first salvo hits at 20+miles or shell defusing American DC or wether it be the "facts" about Wotan blah or Wotan rah (the name Hildegard would have caused much less myths) or that BS would never have sunk, was immune to anything etc, Iowa would have been the likely winner of such an engagement due to her greater firepower, better shells, better deck armour and FC (wether slightly or greatly).
Despite this, BS would have tried to run away, which was futile of course and would half her firepower.

Just my 2 cents.

Btw, I would prefer to be on Yamato in a 1on1 as well.
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Post by Dave Saxton »

I'd take Yamato over Iowa too.

I must disagree with the idea that pre-war or early war Wh was inferior to Class B, However. Who said it was and why? If it was, then why did the Royal Navy replace NCA with essentially the same stuff as Wh post war? Class B is long obsolete, but Chrome/Moly armours similar to Wh became the armour type most used post WWII.

The face plates of the Iowa turrets were penetrable at all reasonable battle ranges too. Looking at the penetration curves for homogenous armour for the 38cm, it looks like the the 38cm could defeat them all the way out to 30km. Remember the face plates are laid back at an angle.

I don't care what anybody say's, beyond 30km is an unreasonable battle range IMO.

I find it interesting that the old proofing angle argument is still taken for granted. US ballistics experts during the war found post 1940 Krupp APC shells (all APC up to 406mm were the same design) had outstanding oblique striking performance.
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Post by ModelMangler »

Hey ya know all those Iowas are just hanging around collecting rust, how 'bout we take a couple out in the ocean and stand them twenty miles apart and have at it with those sixteen inch guns? C'mon, it'll be fun! :idea:
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Karl Heidenreich
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Post by Karl Heidenreich »

I believe that there are enough Battleship buffs around to be on board of both.
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Post by Bgile »

Dave Saxton wrote: The face plates of the Iowa turrets were penetrable at all reasonable battle ranges too. Looking at the penetration curves for homogenous armour for the 38cm, it looks like the the 38cm could defeat them all the way out to 30km. Remember the face plates are laid back at an angle.
The faceplate angle was a plus. It presented a sharp angle to low trajectory high velocity (close range) hits, and only got closer to "normal" impact angle at long ranges where the shells were much less likely to retain enough velocity to penetrate.

Tests were apparently (source: Nathan Okun) performed postwar which showed the British 14" was unable to penetrate the Iowa class faceplates at any range. The shells deformed and ricocheted. In general, it was apparently unlikely for a shell to penetrat any armor thicker than the shell's diameter.

It's a simple matter of physics that the US 16"/50 cal gun was more powerful than the German 15"/47. There is a large difference in muzzle energy, and there is anecdotal evidence that the US Shell performed better at the target.
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Karl Heidenreich
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Post by Karl Heidenreich »

Something to add:
The German 15" shell performance, good or bad, was proven in BB vs. BB combat as was the German armour. We know how it really works due to factual evidence as that from Bismarck´s mission.
We don´t have that factual evidence from the Iowas because they never engaged in BB vs BB combat, we only have test evidence that is not the same as real post action forensics.
On paper the 16"/50 MkVII is a faster and more powerfull gun-shell combination than 15"/47 of Bismarck. But I don´t believe that an Iowa would shoot the German ship and win easily, if wining at all is the climax of such combat.

Best regards.
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