Destroyer armor

[Feinder]

Each "point" of armor in WitP is 1mm.  I'd be inclined to put 3mm on most DDs, maybe 2mm on PGs, and 1mm on PC/SC.  This would help with the strafing issue.  They would still suffer marginal sys dmg and fires from the non-penetrating hits, but would likely not suffer major damage.  I think a 20mm cannon has penetration of 4, which would make them vulnerable to cannon fire.  I think there's a mod somewhere that adds a little bit of armor to DDs, to downgrade the effectiveness of strafing.
 
-F-

[Dili]

huh?

Weight. The sides of a DD is less than 10mm. Maybe around 5-6 and not ballistic hardened

[AU Tiger_MatrixForum]

ORIGINAL: herwin

ORIGINAL: rtrapasso

ORIGINAL: Rommel3

Is there no issue related to game engine?

i think some folks experimented with putting minimal armor on all DDs to simulate the "armor value" of the mild steel (i.e. - non-armor steel) that the hull, superstructure, etc. Iirc, it proved to be a pain, and didn't add anything to the game... there might have been some adverse effects to repair time as well.

As the US industry got geared up to fight the war, they started incorporating armor-grade steel into even routine structural members on even small warships (like DDs). British observers, seeing this and thinking about how many lives it might have saved on their ships "just cried" (i believe the quote is accurate).

UK war-time construction was slap-dash. Good armour-quality steel was expensive and saved for where it was really needed.

The primary expense isn't just cost of the hardened steel itself which merely involves a slightly different amount of carbon in the steel and a few more steps in manufacturing, but also the great difficulty in working it. Hardened steel is more brittle, and less able to withstand thermal stresses from welding. I saw a demonstration at work once where a welder simply tapped the rod on some hardened plate, and it immediately cracked in two. I was impressed. To work the material, the whole piece has to be heated to around 300 F before it is safe to weld. In other words, just supplying the shipyard with ballistic plate isn't enough, they would have to have more equipment, highly trained welders, and a lot more time.
There is a war on you know.

[Nikademus]

ORIGINAL: Dili

huh?

Weight. The sides of a DD is less than 10mm. Maybe around 5-6 and not ballistic hardened

If a larger DD hull is strong enough to support the weight of it's various components, it can handle a little bit of armor protection theoretically. It mostly wasn't seen as cost effective however.

[RevRick]

IIRC, the skin on one of the pre-Fletcher destroyers was 5/8", or roughly about 16mm. The skin of the Fletchers was more on the lines of 1", or 24 mm. I do not have that data readily available, but I think that is the information I read. Any thinner though, and you couldn't even have a tug push against the side, let alone worry about getting shot at.

[racndoc]

In game, Ive had IJN DDs seriously damaged by PT boat machine guns(30%plus system damage)

[Feinder]

This is what I could come up with about Fletchers doing a quick Google search:
 
These proposals did obviously not satisfy the General Board. Although several members proposed further studies of this and that proposed design, the General Board as a whole requested two weeks after the initial proposals had been made that a larger ship be studied, and four new proposals be drawn up. Once made, they drew heavily upon a number of proposals, from within C&R (where a flush-deck hull originated), to the General Board and the Bureau of Engineering. The final ship, which was to have five 5" guns, ten to twelve torpedo tubes, depth charges and K-guns to throw them with, plus most importantly, protection from heavy machine-gun fire in the form of 0.5" STS armor over vital spaces.
 
This became some of the primary concern, since the added weight of the STS and the "parasitic" weight of a heavier and possibly wider hull to sustain the large weight of the armor increased tonnage immensely. When C&R finished the new proposals, they all came out over 2,000 tons. At the same time, the General Board accepted the need both for size and protection. In the final characteristics which the General Board gave out for the 1941 destroyer program, the new ships made good use of their large size: five 5" guns, ten torpedo tubes in quintuble mounts, a 28mm L/73 AA quad mount, four .50cal machine guns, 38 knots, four K-guns and two depth-charge racks, 0.5" STS protection for engines, boilers (both decks and sides), pilothouse and 0,75" STS over the 5" gun director.

 
-F-

[herwin]

ORIGINAL: AU Tiger

The primary expense isn't just cost of the hardened steel itself which merely involves a slightly different amount of carbon in the steel and a few more steps in manufacturing, but also the great difficulty in working it. Hardened steel is more brittle, and less able to withstand thermal stresses from welding. I saw a demonstration at work once where a welder simply tapped the rod on some hardened plate, and it immediately cracked in two. I was impressed. To work the material, the whole piece has to be heated to around 300 F before it is safe to weld. In other words, just supplying the shipyard with ballistic plate isn't enough, they would have to have more equipment, highly trained welders, and a lot more time.
There is a war on you know.

And UK shipyards weren't the most modern in their equipment or construction practices. (I live in Sunderland. 8)

[spence]

From what I remember of the history of the Treasury Class cutters (2 of which I served on) the mild steel shell plating on prewar USN DDs was .375 inches (~9.5mm). The Treasury Class WPGs (Taney in CHS) were "part of the New Deal" and were constructed with twice as much steel in their hulls as a typical DD in part to give them some ice breaking capability but also just so the government could inject more money into the economy (in 1935-1937) by buying more steel to build them. These cutters, which were of roughly DD proportions lengthwise (etc) displaced from 40-60% more than prewar DDs (around the same as a Fletcher) due to the extra steel.

A typical steel hull "shrimper" or coastal freighter also has .375 inch shell plating. Towards the end of my time in the Coast Guard I had the opportunity to observe the effects of .50 cal armor piercing ammunition upon .375 shrimper and coastal freighter shell plating in the context of persuading drug smuggling boats/ships to heave to. Hitting the target with the rounds from a hand directed .50 cal MG on a pitching, rolling, yawing and heaving gun platform was much the most significant problem in the evolution. Those rounds which did hit however caused major problems for whatever the target. On a shrimper, a .50 cal AP round would quite commonly penetrate the shell plating, go through the engine block of one of the boat's diesels and then exit the shell plating on the other side (Smugglers were advised that the engineroom was not a good place to hang out beforehand) causing both fires in the E/R and flooding. Larger diesels (in coastal freighters) might stop the .50 cal rounds but the engines still suffered mightly and the ships invariably were stopped.

I for one would not place any confidence whatever in typical WWII DD shell plating for armor.

[Rommel3]

I'v find what i read But this is for sub armour
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"The ship model is what i've always termed, an "all critical" model, meaning that all of the Hit locations protect critical systems (Belt armor/Deck armor/Tower armor/Device hit + one of the former 3) Thus any device that "penetrates" a location will cause some sort of substantial damage represented by the SYS value every time. SYS also directly impacts maximum speed as well as overall efficiency. Additionally FLT damage can be caused of which the Belt armor hit location causes the most (and pretty much every time)
If a device does not penetrate it causes virtually no damage but "can" cause FIRE damage which combined with a small amount in indicental SYS, CAN lead to substantial damage.....example: hit a BB with 12 big HE bombs that dont penetrate. Initial SYS may be 3% but with 25 Fire levels. After Fire levels are extenquished, SYS may have risen to 14% lowering the ship's efficiency and speed.
There is no middle ground. Either a device penetrates causing immediate critical damage (level dependant on device effect rating) or it doesn't and is goverend by the armor rating of the location compared to the device pen rating. The device pen rating must exceed the armor location to penetrate. IF the ASW routines had been meant to use armor vs pen then they'd follow this same pattern but THEY DO NOT (sorry for the caps Mike, but i've only told Ron this like 6 times and he doesn't want to believe me)
This is why all DC devices in the stock game have 0 penetration. If they worked as per the surface routines, then adding even 1 mm of armor would defeat the device and it would not penetrate yet it does. When i first tested this i did just what i did in the test and gave a sub 10mm of armor and set up one of my standard ASW tests. *Initially* i did NOT watch the combat animation screen but only went directly to the summary to speed the tests. As such i was puzzled by some of the results. Sometimes an Iboat would take as many as 40 hits and show just what i pasted here....a sub with 4% SYS and a happy crew. Other times the sub would take 8 hits and sink, other times it would take 16 hits and be moderately damaged.....then back to 50 hits and no damage. What was happening????
It was then that i started watching the animation screen and was suprised to find that in some cases, one type of DC was never penetrating, while another DC device was always penetrating, while still a third type of DC device penetrated half the time.......Altering the armor of the sub, and/or manipulating the DC pen rating messed with this a bit but still produced an unchartable anomoly of somtimes penetrations and sometimes not.
After testing all variables i came to the one variable that can alter this phenomenum all by itself....the load value (of the DC device). Yeah, sounds nuts but try it.....it works. This is what led me to conclude that the ASW routines were NEVER meant to interact with armor and penetration ratings and thus I concluded that it was not a good road to go down.


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