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So the BBs basically rolled up, emptied their magazines into the bismarck asnd then pulled back.
The Graf Spee had only cruiser type armor and it was penetrated many times during the battle. Reportedly her boiler room was penetrated by an eight inch shell from Exeter.
pinsong
that is pretty much what happened, there has always been a discussion as to whether she was sunk or scuttled
from wiki
Bismarck continued to fly her ensign. With no sign of surrender, despite the unequal struggle, the British were loath to leave Bismarck. Their fuel and shell supplies were low, a demonstration of how difficult it was for a battleship to sink a similar unit, even in an unbalanced engagement; however, when it became obvious that their enemy could not reach port, Rodney, King George V and the destroyers were sent home. Norfolk had no torpedoes left, so Dorsetshire launched three 21-inch (533 mm) torpedoes at comparatively short range, which may have hit Bismarck. The battleship's upper works were almost completely destroyed but her engines were still functioning, although Johannes "Hans" Zimmermann, a boiler room stoker who survived, confirms that salt water had entered the boiler feed lines causing the engineers to reduce speed to seven knots, fearing an explosion,[51] and the hull appeared to be relatively sound; therefore, rather than risk her being captured, survivors have said the order to scuttle and then abandon ship was given. Many of the crew went into the water, but few sailors from the lower engine spaces survived. As Captain Lindemann was presumed killed with all officers after the bridge was hit by a 16-inch (410 mm) shell, it is unclear whether he could have given the order to scuttle.
The KGV class had extensions to the belt forward and aft of the main belt, and the deck armour was also extended forward and aft of the main belt, so her protected length was greater then the length of the citadel.
Obviously Bismarck's belt did not make it "completely safe from flooding from a large number of enemy guns at just about any range" since 2 of the 3 14in hits by Prince of Wales caused heavy flooding on Bismarck and left her "...listing 9 degrees to port and her bow lost 2 metres of freeboard...".
Bismarck's inefficient use of armour left her main belt armour being too shallow and a 14in shell dived under it to cause damage to Bismarck's machinery spaces and cause a 9 degree list.
Part III.
As explained, belt armor alone does not equate to protected bouyancy. The longer belt represented a larger target of thinner armor that could be more easily penetrated.
So if I don't use any lenght of belt on a ship, the ship becomes invulnerable because following your logic, it can't be hit at all...?Nah!
A belt that is penetrated does not protect bouyancy of any kind.
By this logic again using an armor belt is entirely useless, since all except Yamato's could be rather easily penetrated at normal battle ranges.
If that is now your position then one can conclude that Bismarck's longer thinner belt armor was more wasteful than the stronger belts of certain other designs.
This a strange kind of logic - a belt is wasteful if it does not fullfill its function: protect the vitals and prevent flooding as much as possible. Bismarck's vertical armor scheme (belt + turtle deck) was the best of all protecting the vitals, and yes it was incapable of providing much protection against the largest hits below the waterline. This doesn't seem to have been much a problem in practice since as everyone agrees, she proved to be damn hard to sink. Appearantly the design was compensated for this weakness in other areas - sheer size, subdivision, large beam that made counterflooding easy.
In comparison the stronger belts of certain other designs were entirely incapable of preventing either flooding, or catastrophic damage to the vitals. The thickest vertical belt used on the KGV was incapble of withstanding holing out to 23 800 yards against contemporary 15" guns, and shells could enter the magazines out to 21 000 yards. Ka-boom vs a bit of seawater in the laundry room. Its an easy choice IMHO.
Bismarck's bouyancy was not threatened by the bow hit. Lutzow's situation i've gone over already.
We agree tha the ship was not endangered directly due to bow hits, however flooding in the bow from a passing shell (which you consider ideal) caused temporary loss of speed and bow-down. Its not an imminent danger, but can be a problem in a long-run battle.
Lutzow sank as a result of hits to the bow causing flooding, I think we can agree on that. Yes there were other factors contributing to the loss.
However the idea that the ends of the ships are sacrificial in their nature and need no protection at all does not seem to have been much accepted with designers
that is incorrect.
I never said there was a middle belt on Bismarck. Hood was used as an example demonstrating the weight penalties of having multiple belt's of varying thicknesses and the restrictions it imposes on primary belt armor depth and thickness, as well as demonstrating the added vulnerability to modern heavy shellfire.
The designer's insistance on provisioning an upper belt of 145mm cost weight and took away displacement that might have been used to thicken the primary belt.
This belt would be of no use against heavy shellfire and as mentioned the upper belt's function in keeping out medium caliber shellfire proved to be an overestimation as well.
Reducing barbette thickness behind such a belt does not compensate for a singular thicker layer of armor.
Seperate layers of armor thicknesses are weaker balistically than one single thickness. The same principle applies to deck armor. A single homogenous layer of deck armor is stronger than either two seperate decks who's thickness equals that of the single deck that consists of two layers of armor sandwiched together.
This is not supported by any research I have read including Garzke and Dunn's extensive study of the class (Axis Battleships of WWII) I would be interested in seeing evidence to support this declaration.
any hit on the main belt would be rejected into the upper works, as you are well aware, and make mess of the laundry room but at least the ship doesn't go kaboom or to a full stop.
Where data and power transmission systems are located as well.
Placing the deck armor on top of the primarry belt increases the area of protected bouyancy against heavy shellfire. A splinter deck underneath the primary armor deck (as provisioned on USN battleships) was an integral part of the A/N system as it was meant to catch any fragments resulting from shell impacts on the primary armor deck...either shell fragments and/or deck armor fragments keeping the below spaces intact.
Don't be silly, a 145 mm armor plate is was certainly proof against UK (or anyone else's) 152mm shellfire.
I disagree on that, it did not impose any weight penalty worth speaking of - [3 tripple vs 4 twin]
That is incorrect. See Garzke Dunn, Friedman, D.K Brown. for more details.
I seriously doubt that the example of VITTORIO VENETO at MATAPAN from an British aerial torpedo is comparable to the experience of BISMARCK.
I would also liek to refer once more to the 2nd torpedhit sustained by the BISMARCK in this event. NIKEDAMIUS mentioned that according to W. Garzke, the hit resulted in tearing damage to the TB´s welding seams, resulting in minor progressive flooding beyond it.
I challange Garzke and his interpretation. It is wrong from two points: At first, when he wrote this, there was no wreckage analysis aviable, which could support his speculation and survicors testimony point to different behavior of the TB (which again later was confirmed by wreckage analysis conducted with video documentation of the torpedo bulkhead)
. Secondly, BISMARCK´s torpedo bulkhead was not welded. According to the BAUBESCHREIBUNG SCHLACHTSCHIFF F the torpedobulkhead of BISMARCK (and TIRPITZ for that matter) was rivetted and not welded, because it was feared that seams of welds may fail under
stress. The HINDENBURG class was scheduled to have welded torpedobulkheads, not the BISMARCK class. W. Garzke made a mistake.
Garzke and Dunn also made a mistake in considering the effects of the final torpedoattack to be substantial in the sinking. This was in part driven by an attempt to proove that the measures of the german crew to scuttle the ship had little to do with the sinking and only hastened the event.
Subsequent research on the other hand indicated that the ship had enough buoyoncy reserve to stay afloat for at least two days when the torpedoing was carried out by RODNEY and DORSETSHIRE, assuming progressive cumulative flooding takes place.
CAMERON is no naval architect, but so is GARZKE.
Another point of discussion refers to the YAMATO´s TDS. As I said,
ANY main bulkhead beeing of dissimilar material is a cause of errors and failures
The relevant document is
US technical mission to Japan
No. S-06-2
Reports of damage to japanese warships, artcile 2 (42p.)
YAMATO(BB), MUSASHI(BB),
SHINANO (CV), TAIHO (CV).
Issued january 6th, 1946.
***To state that MUSASHI was the ship with most damage received by underwater damage ever is therefore grossly incorrect, when no more than a total of 6,000 lbs TORPEX was involved in the sinking of the ship (evenly placed starboard and port).
Considering the example of SCHARNHORST returns an equal number of torpedo hits sustained by the ship, but these were generally DD or CL based weapons and correspondingly had in between 750 and 805 lbs TORPEX each instead of 600lbs. It should also be noted that the YAMATO class is roughly twice the size of SCHARNHORST.
I am afraid you are the one being incorrect here. Okun:
The Italians politely disagree - the use of separate 70mm decapping belt with a 280mm belt behind it proved to offer considerably higher ballistic protection than equivalent weight and thickness found on certain other designs of the era.
The French also seem to disagree here as they used a - albeit much thinner - turtle deck behind their belt armor to provide additional protection, much like Bismarck did.
Vertical armor used on naval vessels was face hardened however, with the surface of the armor hardened to extreme levels, designed to shatter projectiles nose on impact, grossly reducing penetration capabilities or even breaking up the projectile and rendering it inert. For this reason projectiles were built with a sacrificable armor piercing cap, designed to be shattered by the face hardened top layers of armor, so the actual nose of the AP projectile can do the penetration.
If you mean fire control data, the forward communications tube was behind a 220 mm thick armored barbette of 1 meter in diameter, running from the station down to the main armored deck. Good luck with that after going through the belt, bouncing back from the main armored deck. The FC rooms (two of them, one aft, one fore) were under the main under deck.
Yes but to stop shell fragments you need to spread additional 20-30mm worth of armor over a very large area (as decks are far larger in area than belts). Essentially wasted weight as it performs no other function.. And there's still the kaboom problem when something big hits the main belt at normal battle ranges, say, near the magazines..?
So kindly show me a 6" gun that could be expected to penetrate a 145 mm face hardened plate at any reasonable range.
I am afraid you are incorrect here - see Jack Brower for more details. Triple three gun turrets were considered for Bismarck at around March-April 1935. They were dismissed on the basis of additional weight.
Also look up the weight of the barbettes and turrets of Vittorio Veneto (3x3) vs. Bismarck (4x2). You will be surprised
Its a bit a matter of defintition, but as far as I am aware, this was only splinter protection, generally not considered protected lenght (since it doesn't really offer protection).
That's why I said large number of guns, and not all kind of guns.
Appearantly the King George V class's use of belt armor was even more inefficient, since even though they used a very deep and thicker belt, at much greater expanse of weight, Bismarck's 15" shells was still capable of diving under it and cause similiar flooding, despite the shell not exploding properly. That's lucky because KGV's internal bulkhead was somewhat weaker than on Bismarck.
As for the 14" hitting the German ship under the belt, it didn't damage or get into the machinery rooms. The 45mm torpedo bulkhead contained the explosion, but iirc some weld seams broke and water poured in. The design itself seems quite sound to me, the workmanship on the welds less so - appearantly a common problem of the era.
As a result one of the four electric generator room was flooded, however it was of little consequence since the ship had 200% reserves in that regard (redundancy again!). IIRC after the battle water was pumped out, and the leaks contained, the generators re-started again, but later a torpedo hit the same damaged spot and tore up the welds again, and the generator room was flooded again.
In case of US and british fuzes, which deleted the double plate sensitivity and required a single, thick plate to trigger the fuze this may be the case. With german fuzes it´s not. They had single double plate sensitivity with graze function, meaning that any projectile striking a deck (even unarmoured) would usually trigger the fuze of an APC and many cases when two plates in short succession (even unarmoured) are penetrated would trigger the fuze as well.
Bismarck's Final Battle - Part 1
The second shell struck the port side of Bismarck somewhere below the 320-mm main side belt in compartment XIV (in way of the fore bridge tower). This shell defeated the side protective system and exploded against the 45mm torpedo bulkhead. Fragments from the explosion penetrated the bounding bulkhead of the portside cable ways and the main transverse bulkhead between the forward port turbo-generator compartment and the port boiler room. The turbo-generator room quickly filled with water. The boiler room flooded at a much slower rate through tears in welded seams in the main subdivision bulkhead. These leaks were controlled by plugging the torn welds with canvas hammocks.7
None of which changes the fact that a single layer of armor is provides more resistance vs. seperate multiple layers.
The italian example represents a single belt of armor which happenes to be made up of different materials in order to promote the idea of de-capping, which is not an exact science. They did not place a single thinner belt on the outer hull, followed by one or more "belts" internally to promote the shattering and breaking up of the shell. As mentioned their solution had merit but did not prove 100% effective in tests nor was the system tested in battle.
The US and UK took a more conventional approach to 'decapping' with face hardened armor.
The latter in particular approached the issue from a quality persective and worked to increase the effectiveness of their Cemented Armor (CA) for the KGV class. It's been estimated that this armor, vs. heavy caliber shells was 25% more effective than it's contemporaries.
The slope created by the low armor turtleback will help direct shells up into upper decks and superstructure. A battleship's systems are not all located under the primary armor deck. It is true that these systems (including radar and optical fire control systems) can't be fully protected on any battleship and soft kill/disablement is a viable alternative to outright sinking via catastrophic damage. The low slung armor belt also reduced, as mentioned the actual protected bouyancy of the ship.
Stopping shell fragments is an important consideration independent of how high or low the deck is placed. The Americans introduced this feature into their battleships on the correct acknowledgement that plunging shellfire is not a simple matter of rejection or penetration. Often armor spalling occurs even in situations where the shell itself is rejected. In other situations a partial penetration might be effected. Placing the armor deck higher, in addition to increasing the area of protected buoyancy also allows more solid protection of critical spaces from plunging fire. The lower splinter deck of SPS (Special Treatment Steel) thus enhances the protective effect provided by the primary armor deck.
The ranges in which the British cruisers defeated it was apparently considered reasonable.
I did.....per Brower's text; "Nine 380mm guns in triple turrets were also considered because it would have meant an increase over the desired set displacement." This sentence does not refute Garzke's design commentary.
Littorio's turrets to use one example were more heavily armored than Bismarck's and contained an additional gun barrel.
Naturally they were heavier one for one vs. one of Bismarck's, hence your simple math exercise.
No, not surprised because the weight savings issue is not a simple matter of comparing turret weights. A 3 turret design allows weight savings overall when all factors are considered, and allows armor to be increased.
Some really great info here - makes a great thread. And I have to give kudos to you guys for keeping it civil. Great stuff!!