Effectiveness of Naval Armor

So I'm wondering if anyone can tell me, or can direct me to a resource that can, how to determine the effectiveness of naval armor, ideally from the pre-dreadnought period. Specifically I'm looking for a way to figure out how much protection a given thickness of armor would provide against a given size of shell. i.e 6" of armor will stop a 3" shell at 4000 yards, 4" at 5000 yards and so on.

Thanks in advance,
Jack
 

Flubber

Banned
The navweps board would be a place to start.

Looking up a man named Nathan Okun would be another.
 
There's a program called FACEHARD and another called GKdos100 that will probably do what you want. WARNING-you are entering the world of ballistics-heavy mathemetics ahead!

Navweaps.com is the place to go for this. In some of the threads there are links to download these programs.
 
Thanks for the replies! I had a look around and Navweaps.com definitely looks like the place for what I'm looking for.


Grognard49: Do you happen to know if those programs will work on macs?
 

NothingNow

Banned
Thanks for the replies! I had a look around and Navweaps.com definitely looks like the place for what I'm looking for.


Grognard49: Do you happen to know if those programs will work on macs?

Yeah, you'll need to run it in DOSbox anyway, so it'll work on OSX through that.
 

Delta Force

Banned
Do you want exact calculations or approximations? I can link you to some easy to use calculators, but they are more approximations and relative values (as in comparing to known shells) than exact.

Also, you can simply compare existing shells to find about how much the armor will penetrate. NavWeaps is a good source for historical cannons and shells. Details are rather hard to come by for the older blackpowder guns on the older pre-dreadnoughts though, and sometimes it isn't clear what type of shell, armor, and test scenario is being used with the tables on NavWeaps.

What kind of shells and armor do you have in mind by the way?
 
approximations are just fine. I've had a few ideas for pre-dreadnought naval TL's bouncing around in my head for awhile and I wanted to be sure that I get the technical aspects right (speaking for myself I find this the most interesting aspect of naval TL's). If I write a battle scene I'd like to be realistic in the damage dealt and sustained by ships.

As for shells in armor I was thinking along the lines of Krupp Armor and the Vickers 12" guns( apologies if I misunderstood the question, it's pretty late as of writing)
 
I am researching for a timeline:), specifically one about the Russo-Japanese War but almost exclusively naval. Basic idea is that the Russian fleet breaks out of Port Arthur and runs into the Japanese where glorious battleship-on-battleship action ensues. Hence the research on naval armor.
 

sharlin

Banned
It depends on the type of gun really. A big French 13.4 inch gun on one of their Marceau class ships would have issues penetrating 6 inches of Krupp's armour thanks to the design of the shell. A modern high velocity round from say a 1904 pre-dreadnought would be able to punch through the almost standard 9 inches of armour but not at long ranges. Gunnery of the time was more about disabling a ship first and that meant large volumes of HE rounds. At Tishuma the Japanese 12 inch guns, all modern peices apparently didn't penetrate the Russan battleships belts or turrets, but their HE shells wreaked terrible damage on their thinly protected upperworks, a problem with the Russian ships French styled armour scheme.

I dislike self advertising but you might like this.

https://www.alternatehistory.com/discussion/showthread.php?t=230861

Also don't forget that most pre-dread gunfights were going to take place at fairly short range 7 - 9000 yards would be seen a very very long ranges, the RN had trained to fight at 2000 yards until Fisher came along and modernised the RN's thinking and training. I'd say that the main guns of a pre-dread were its secondary guns, the 6 inchers. THeir rate of fire worked perfectly with continuious aim and the volume of fire would enable you to knock out more enemy guns and cause fires whilst landing the odd heavy hit with your main guns.
 
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Sharlin,
Your timeline was actually the thing that got me interested in pre-dreadnought ships in the first place.

I didn't know that individual shell design had such a large effect on performance . I also didn't know that the Russian's armor belts weren't penetrated. All much appreciated and very helpful.
 

sharlin

Banned
Its more that the French guns were quite old and not really designed to punch through something like Krupp's armour. The guns on the Marceau for example were just a solid iron shell with a slightly hardened cap but otherwise they were quite crude, just a fairly high velocity lump of solid metal. HE Shells had thin shell walls so when they hit and burst it added more to the fragmentation effect. I recall reading somewhere that the RN tried an experiment in the 1900's with a HE shell where its casing was shaped and indented more like a modern grenades to aid with the fragmentation effect, but it just made it inaccurate and was dropped.

A 1904 12 inch gun had a muzzle velocity of 796 meters per second, an older 13.4 did 614 mps. Thats a massive difference when it comes to penetrating armour and the older shell might well shatter when it hits armour it simply was never made to encounter.

The Russian ships were for the most part based on French designs and the French did feature a thin but fairly thick belt with equal armour on the turrets, although the Russians didn't copy the odd hydralic system of how French turrets turned. It was rather unique the turret structure would be lifted off its mounting by about a centermeter by hydralic jacks that were on a rotating base, that then turned and lowered the turret down. It was stable and very chintzy in terms of shiny new tech but vulnerable to battle damage. Most of the Russian ships were a mixbag, the old ones featured older styles of armour but it was usually very thick over the vitals, or the newest ships had brand new Krupps armour but not enough of it. The Borodino's apart from looking very nice and having an awesome name were really bad ships. And I'm glad I helped inspire you Captain Jack! :)
 
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So I'm wondering if anyone can tell me, or can direct me to a resource that can, how to determine the effectiveness of naval armor, ideally from the pre-dreadnought period. Specifically I'm looking for a way to figure out how much protection a given thickness of armor would provide against a given size of shell. i.e 6" of armor will stop a 3" shell at 4000 yards, 4" at 5000 yards and so on.

Thanks in advance,
Jack

Try any libraries for Brassey's Naval Annual for the early 1900s. The 1913 Naval Annual was reprinted in 1970; I have a copy packed away.

It included a whole set of gunnery tables which gave penetration values for various calibers of guns at various ranges. Lots of factors were included, including wrought iron versus steel of various types, type of shell, and model of gun.

There were tables for each major navy and also tables provided by all the major armament manufacturers: Vickers, Krupp, Bofors, Skoda, Bethlehem Steel, and others.

This should give you anything you need.

It's available from Google Books

http://books.google.com/books?id=NQJAAAAAYAAJ

but very hard to browse and read. (The tables are on pages 391-412.)
 

BlondieBC

Banned
approximations are just fine. I've had a few ideas for pre-dreadnought naval TL's bouncing around in my head for awhile and I wanted to be sure that I get the technical aspects right (speaking for myself I find this the most interesting aspect of naval TL's). If I write a battle scene I'd like to be realistic in the damage dealt and sustained by ships.

As for shells in armor I was thinking along the lines of Krupp Armor and the Vickers 12" guns( apologies if I misunderstood the question, it's pretty late as of writing)

Navweapons is a good site. But also remember the calculations are of a shell made exactly to factory specs fired against armor that works just like specs. In a real battle, we have defect shells. Armor that is stronger or weaker than specs from shipyard. Shell hits at unexpected angles. So for some examples from battles to think about.


- UK flash suppression in WW1 would not necessarily stop an explosion, even if in perfect repaired. Learned in post battle fights.
- Defective UK shells at Jutland.
- Several battles where shells went under armor belt.
- USS Arizona may have been lost to black powder bags for catapult for planes. Not understood risk when ship designed.
- UK BC took off some safety items and procedures at Jutland.
 

BlondieBC

Banned
..

Also don't forget that most pre-dread gunfights were going to take place at fairly short range 7 - 9000 yards would be seen a very very long ranges, the RN had trained to fight at 2000 yards until Fisher came along and modernised the RN's thinking and training. I'd say that the main guns of a pre-dread were its secondary guns, the 6 inchers. THeir rate of fire worked perfectly with continuious aim and the volume of fire would enable you to knock out more enemy guns and cause fires whilst landing the odd heavy hit with your main guns.

Agreed. On predreads, the main gun had a low rate of fire. The concept was that the faster firing, smaller guns would wreck the upper hull and disable the enemy ship. The main guns are to mainly punch holes in main belt to sink ship. In theory on all ships, if you fail to punch a hole in main armor belt, the ship will float. In theory. As time went by, improvements in gun and shells were first done to the smaller guns, because it was easier to get say a 105mm gun working right than a 300 mm or so gun.

Or put another way, if you took the all big gun concept for the dreadnaught and took it back in time to 1890, it probably does not work very well because the main guns are not up to the job. Or at least it will not work well in many battles if the other side can close the range and use the smaller guns.
 

BlondieBC

Banned
Sharlin,
Your timeline was actually the thing that got me interested in pre-dreadnought ships in the first place.

I didn't know that individual shell design had such a large effect on performance . I also didn't know that the Russian's armor belts weren't penetrated. All much appreciated and very helpful.

It is huge. Some of the main predread guns in the late 1800's did not always use exploding shot, much less AP shot. Of course these smaller ships had less armor and had lesser quality armor. Just like today we try to build a weapon that will penetrate a tanks armor, but not by too much. And we may use the weapon decades after it should have been replace, the same thing happened back in the day of armor ships. Just as using a LAW on the front armor of a tank is a joke, using a 20 year old pre-dread on the armor of a new pre-dread or dread is also not wise. Part of the horrible economics of the BB race relates to the rapid improvement in all areas of design - guns, shells, armor, engines, etc. Ships designed for decades of life were old, flawed ships when 10-15 years old. Cost a fortune. Look at ships in reserve when WW1 starts as an example. Or how many not more than 15-25 year old ships get converted to other things.

To a large extent, the deployment of new technology to warships was delayed during the age of unrivaled UK domination (call it 1850 to 1900). The basic metalurgy and other technology improved, but as a cost savings measure, these technologies were slowly applied to new ships. Then the great naval race began, and we see big jumps as applied naval technology caught up to what was already know as basic science.
 
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