Slitherine

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ORIGINAL: juliet7bravo

Sometimes the designers got it right...others, they got it wrong. Look at the Graf Spee...too slow to run, too big to hide, and main guns that both too big, and too small.

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Remember that the basic concept was from about 1926.

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The H-Klass was no battleline BB.

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Why should the H-Klasse use it's big guns against merchants, especially as ammunition is limited and armour piercing shells are very ineffective against unarmoured targets?

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What most people who so fervently dump on the Reichsmarine ships fail to consider is the circumstances under which those ships were designed and built.

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ORIGINAL: mikemike

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ORIGINAL: juliet7bravo

Sometimes the designers got it right...others, they got it wrong. Look at the Graf Spee...too slow to run, too big to hide, and main guns that both too big, and too small.

Too facile a condemnation of the Panzerschiffe. Remember that the basic concept was from about 1926. These ships had to be the German Battle Line and as such were replacements for the "Deutschland" and "Hannover" class pre-dreadnoughts - but limited to an even lower displacement (10k tons - the pre-dreadnoughts were about 13,5k). The only gun caliber the allied Control Commission would have allowed for these ships was 280 mm (I think there is a paragraph in the Versailles Treaty that stated how many guns of which calibers the German Navy was allowed to own, and at the upper end that meant 150 mm, 170 mm, and 280 mm - nothing else). Now you have 1926 technology to work with - pray tell me what the right compromise would have looked like in your opinion. At least the Panzerschiffe were aimed squarely at a capability gap the French Navy - the only conceivable enemy in 1926 - had at the time: the only ships able to stand up to 280 mm guns were far too slow to catch them. Any heavy ships built in France and Germany after that were part of a private arms race between those two navies - reaction and counter-reaction: Deutschland - Dunkerque - Scharnhorst - Strasbourg - Richelieu - Bismarck - Clemenceau.

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The size of the holes, and the substantial flooding it caused with the concurrent change in trim, especially to the bow plane was very serious and demonstrates how far damage can reach....and thats just the direct physical damage. Shock and flooding damages can reach still further. You are free to dismiss it by blaming the crew. In fairness though, since Bismarck's steering arragements receive much scrutiny because of the one hit, its just as fair to consider Littorio's 3 torpedo hits and how it would have impacted her survival had she been in Bismarck's place in the stormy Atlantic that fateful day.

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The designers expected the Pugliese TBD system to absorb most if not all of the blast. There's design theory, and then there's real life. It doesn't always work out the way the designers want or expect.

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Its not a misunderstanding. To fully appreciate the situation Luthjens and company faced you have to take into account the situation they and the ship were in. Littorio's more dispersed steering arrangement does indeed make her LESS suspectible to being fully disabled by such a hit. However what you can't say, and from which point i have been arguing, is that a full or mortal disablement would never occur, more so if more than one torpedo had struck home in other areas. In such a state as Bismarck were in, Littorio's aux steering system, assuming it wasn't disabled by shock and flood damage might not have overcome the sea state, more so were she down heavily by the bow as with what occured at Taranto. Thats the danger of making absolute statements based on one incident. Yet you choose to dismiss Littorio's poor preformance at Tarnato and blame it on the crew, but in Bismarck's case the disablement of her steering and the inability of the crew to repair it or jury rig the system because of outside variables warrents a label of "Design Flaw" on the class as a whole (though I note not in Gazarke despite specific attn to this subject.)

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Had she had a more traditional two rudder arrangement like most other BB's she might have avoided the torpedoes that did hit home knocking them out of service. Design Flaw? no......Design choice....same as with Bismarck, or North Carolina for that matter.

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I was much impressed by the Vittorio Veneto’s zig-zagging. That of the Italia was not as good.

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One opposite example,put Bismarck at Matapan instead of Vittorio Veneto and Italians would won the day
That english cruisers which approach VV to less then 20000 yards would now be at the bottom of Mediteranian sea

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Matapan, Greece. c. 1941. 15 inch shells exploding in the water between HMS Gloucester and HMAS Perth. Seen from HMS Gloucester during the battle of Matapan in the Ionian Sea.

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We believe that part of the stern collapsed onto the rudders, as happened with the Prinz Eugen and armored cruiser Lützow, or was damaged in such a way that it was impossible to steer the ship by either manual or mechanical means. It would have been necessary to cut away structure which was covered by surging water. In any event, the repair of such damage was beyond the capability and material provided aboard the Bismarck, even if weather and battle conditions had been more favorable. The stern structure was massively damaged and eventually failed.

There is remarkable similarity between the Bismarck damage and a similar torpedo hit on the stern of Prinz Eugen on 23 February 1942. Dr. Erwin Strohbusch, who directed the repairs of this heavy cruiser in Norway, wrote to us that this incident, and an earlier one on the armored cruiser Lützow, whose stern also collapsed from a torpedo hit, indicated a structural flaw in the stern design of German armored ships, heavy cruisers, battleships, and battlecruisers. Improvements were made to the stern structures of Admiral Hipper, Lützow, Tirpitz, Admiral Scheer and Scharnhorst during 1942-1943.

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The H-Klass was no battleline BB.


That's an excellent depiction of German design confusion--a ship-of-the-battle-line not meant for the line of battle.

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ORIGINAL: Historiker

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The H-Klass was no battleline BB.


That's an excellent depiction of German design confusion--a ship-of-the-battle-line not meant for the line of battle.

The H-class may have been (if it were built) a waste of ressources, but the design ment it was both: A commerce raider and - if needed - a ship for the battle line.

The Z-Plan was the plan against Britain. When it was designed, Britain already had 15 (?) Battleships while Germany just had four, of which two weren't the right to fight against the British ones.
It's irrealistic to believe, you could get a stronger battleline within the next twenty years, when the enemy starts with such a numeric superiority. Even after the Drednought, which lets all navies start at zero, this wasn't acchieved.
So what could you do?

With H-Klasse BBs, you have superior commerce raiders. They have a strong to superior armement with heavy armour and an amazing range (They might run through the denmark straight down to the Rio de la plata and back with a 20% backup for battle). But as they are stronger than any of Britains (old) BBs, they can attack even protected convois were they find them.

It doesn't make sense to build a battle line if you have just 20-30% of the enemy's ships, but with two or three H-Klasse sailing together, no enemy convoi can ever be save, as the enemy doesn't now where and if they'll strike and consequently can never protect his convois enough.

I'm neither a ship designer nor a real expert in this profession, but IMO, the H-Klasse would have been the absolutly right thing for the described mission. In combination with weaker armed BCs and the new P-class, they might have caused real problems (in times where radar wasn't known and the threat from carrier bourne planes wasn't recognized, yet).

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ORIGINAL: Historiker

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The H-Klass was no battleline BB.


That's an excellent depiction of German design confusion--a ship-of-the-battle-line not meant for the line of battle.

The H-class may have been (if it were built) a waste of ressources, but the design ment it was both: A commerce raider and - if needed - a ship for the battle line.

The Z-Plan was the plan against Britain. When it was designed, Britain already had 15 (?) Battleships while Germany just had four, of which two weren't the right to fight against the British ones.
It's irrealistic to believe, you could get a stronger battleline within the next twenty years, when the enemy starts with such a numeric superiority. Even after the Drednought, which lets all navies start at zero, this wasn't acchieved.
So what could you do?

With H-Klasse BBs, you have superior commerce raiders. They have a strong to superior armement with heavy armour and an amazing range (They might run through the denmark straight down to the Rio de la plata and back with a 20% backup for battle). But as they are stronger than any of Britains (old) BBs, they can attack even protected convois were they find them.

It doesn't make sense to build a battle line if you have just 20-30% of the enemy's ships, but with two or three H-Klasse sailing together, no enemy convoi can ever be save, as the enemy doesn't now where and if they'll strike and consequently can never protect his convois enough.

I'm neither a ship designer nor a real expert in this profession, but IMO, the H-Klasse would have been the absolutly right thing for the described mission. In combination with weaker armed BCs and the new P-class, they might have caused real problems (in times where radar wasn't known and the threat from carrier bourne planes wasn't recognized, yet).

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ORIGINAL: LowCommand



As a note, most historian's and Eisenhower, came up with a list of "The" weapons that won WWII. It usually runs something like:
LST
Liberty
DUWK
Duce and a half
Bulldozer
C47
M1 Rifle

Note that only the M1 is normally considered a weapon.

Never argue with an idiot, he will only drag you down to his level and beat you with experience.

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ORIGINAL: swift

In his ways Dönitz was right - the best ships for commerce raiding - for the German Kriegsmarine - was the u-boat.

look at the amount of everything you would have needed for a H class ship ( in RL they even invested lots of money material in them )

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ORIGINAL: mikemike

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ORIGINAL: rtrapasso

In Re: Type XXI - see Clay Blair's book Hitler's U-Boat War - The Hunted 1942-1945 (Blair has been accused of being way over the top in being pro-U-boat, so if anything he is tends to be too forgiving of their faults) - pages 709-710 (paperback edition) - thi s passage from page 710 (discussing the faults of the type XXI): "Impractical Hydraulic System. The main lines, accumulators, cylinders and pistons of the hydraulic gear for operating the diving planes, rudder, torpedo-tube outer doors, and antiaircraft gun turrets on the bridge were too complex and delicate and were located outside (emphasis in the original text, not mine) the pressure hull. This gear was therefore subject to saltwater leakage, corrosion, and enemy weaponry. It could not be repaired from inside the pressure hull."

Blair devotes another section describing the finding of a U.S. assessment team.

Other problems of the Type XXI mentioned:

- Poor Structural Integrity (actual diving depth was less than the later type VII).
- Underpowered Diesel Engines
- Poor Habitability and Sanitation (i.e.: drinking and washing water was interconnected.)

Other authors have mentioned poor surface maneuverability, but this is a problem common to streamlined subs in general.


As for the stern weakness of the Bismarck and other large German ships - several developed rather catastrophic failure (not just the CA mentioned) but it is late and i should have been asleep 1 hour ago, so i won't pursue this at the moment...

I've never seen that book you refer to, but others have commented on Clay Blair's position. The hydraulics system of the Type 21 was overly complicated, one of the many "clever" design features inherited from the Type 18 which was designed by the Walther team that comprised able engineers, but nobody who had any experience with design or operation of submarines. The hydraulic actuation of the rudders had to be completely redesigned before it worked properly. But I've never heard of the system being substantially outside the pressure hull - you know that one of the boats was used for more than twenty years postwar as a test&development vehicle which tends to suggest that long-term serviceability of those systems can't have been much of a problem. As I said, had vital systems been vulnerable to that extent, the type would never have been accepted for service, not even under the desperate circumstances prevailing.

I read the relevant passages in Eberhard Rössler, "U-Boottyp XXI" (U-Boat Type XXI), a very detailed monograph, where I found this (my translation) " Difficulties were especially caused by the hydraulic equipment to retract and move the forward diving planes which was fitted outside the pressure hull. Great trouble was caused by contamination of the hydraulic fluid by seawater which led to damage to the pumps. This occured especially with the AA turret drives ... which therefore late in 1944 received their own, isolated hydraulic circuit." Meaning, yes, parts of the hydraulic systems were outside the pressure hull, but it was obviously felt that this would not negatively impact the combatworthiness of the type.

BTW, the mechanism of the forward planes was copied from the Dutch O25 class. The Dutch apparently didn't see any particular problem with this arrangement, either.

U.S. assessment teams are always dismissive of foreign kit, so that evaluation doesn't surprise me. I assume they didn't mention the torpedo reload arrangement that allowed firing the second full salvo just eleven minutes after the first. Does anybody know how long it took the crew of a Gato to reload all six tubes?

That the strength of the pressure hull wasn't what was intended was suspected in 1944 already - curse of the double-bubble hull: at the time no mathematical methods existed that would have allowed precise calculation of such a pressure vessel, and the lower lobe of the pressure hull was designed by estimate. Design diving depth was 133 metres, meaning a combat diving depth of 220 metres and a crush depth of 330 metres, which was comparable to the VIIC boats. Tests in a pressure dock showed that the lower lobe of the hull collapsed at a pressure of 31,5 atmospheres (equivalent to a depth of about 315 metres), but no type 21 went deeper than 220 metres, deep-diving trials in Norway were terminated at that depth because the "pressure-tight" emergency raft containers imploded at that depth.

Underpowered diesels? This were not fleet submarines, designed for maximum surface speed. The diesels just had to be powerful enough to recharge the batteries in an acceptable time. The diesels were turbosupercharged 6-cylinder versions of the MAN M9V 40/46 which powered the Type IX boats, developing 2000 hp each. Unfortunately, the afterthought of a snorkel fitted to the Type 21's had an inadequate cross section that choked the superchargers thus cutting output to 1400 hp, which was still adequate, if not ideal, for the boats. BTW, the first installations of the M9V 40/46 were U.S. Submarines Cachalot and Cuttlefish, whose crews were unable to properly operate and maintain the engines. The crews of more than 170 Type IX boats never had that kind of trouble. Problem of the engines? I don't think so.

As to habitability, the Type 21's probably couldn't compare to the floating ice-cream parlors the USN was operating, but they were worlds better than the Type VII and IX boats; certainly their crews had no complaints. On the other hand, if the US boats had tried to operate in the North Atlantic in the same way as the U-Boats, the ASW forces would have caught them routinely on the surface, because their crash dives could have been timed with a tear-off calendar. US submarines either attacked completely submerged or stayed on the surface and fought it out. In the North Atlantic they wouldn't have been any more successful than the Italian boats.

Maneuvering the XXI's on the surface was even more awkward than caused by the hull shape alone because the propeller shafts were so widely splayed outwards. The turning circle was double that of the Type IX boats; to minimize the turning radius, the inner propeller had to be run faster than the outer propeller, which is the opposite of normal behaviour.

I'll freely concede that the Type 21's were a hastily slapped-together contingency design with many flaws and a frequently sub-optimal quality of construction, but they would have caused a whole new world of hurt for Allied ASW forces if they had gone into combat in significant numbers.

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They might run through the denmark straight down to the Rio de la plata and back with a 20% backup for battle

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To give you an idea of the problem the KM had working out sane missions for its ships, the design mission of the Prinz Eugen and its sisters was to attack French troop convoys in the Mediterranean.

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Which destroyers and cruisers are going to escort them? The Germans were left with these massive investments which could prowl the world's seas only on their own.

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ORIGINAL: Dili

The size of the holes is mostly the same(for similar effective detonations) in all similar ships since the outside hull is always weak, what matters is what is behind it or not and if it can stop the water.

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I dont dismiss the crew, italian High Command did, they were retrained and were reorganized(Source: Orizzonte Mare,Corazatte Vittorio Veneto Vol.2, pag.15), also it is my bias that a ship looses efficiency when in Harbour. For example Vailant and Queen Elizabeth might have not been sunk in Alexandria if the explosion would have occured at sea. Note that in image i have linked(for some reason the forum didnt let me upload yesterday) you can see in all images how the ships went in the water after those hits.

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In Taranto only one hit was in Pugliese system, the hit below A turret while there the Pugliese system is already in minor size. To make any judgement we would need information we dont have: how much water went there.

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[Second:HMS Nelson is evidence that steering with engines only is no problem (and not even including auxiliary rudders), due to enemy attacks(U-56 one of them a torpedo that didnt detonated but stuck the rudder, or just because the fragile thing broke and had some times to resort to propeller only steering.

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Strange reference since Bismarck rudder size was tiny and was only one...(post edit: i was wrong they were two small ones).
Littorios were known as very maneuverable. The auxiliary rudders were almost like another rudder 38m2 Vs 32m2. Also as i have said i dont think a design flaw is something that have clear trade offs and that they seem sensible even if i favour other option.

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There is remarkable similarity between the Bismarck damage and a similar torpedo hit on the stern of Prinz Eugen on 23 February 1942. Dr. Erwin Strohbusch, who directed the repairs of this heavy cruiser in Norway, wrote to us that this incident, and an earlier one on the armored cruiser Lützow, whose stern also collapsed from a torpedo hit, indicated a structural flaw in the stern design of German armored ships, heavy cruisers, battleships, and battlecruisers. Improvements were made to the stern structures of Admiral Hipper, Lützow, Tirpitz, Admiral Scheer and Scharnhorst during 1942-1943.

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ORIGINAL: Tiornu

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They might run through the denmark straight down to the Rio de la plata and back with a 20% backup for battle

Which destroyers and cruisers are going to escort them? The Germans were left with these massive investments which could prowl the world's seas only on their own.

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To give you an idea of the problem the KM had working out sane missions for its ships, the design mission of the Prinz Eugen and its sisters was to attack French troop convoys in the Mediterranean.

That's interesting. Can you cite a source?

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Except in those cases where it isn't. What was behind it in this case proved insufficient to stop massive progressive flooding. Regardless, the main point was that damage has a far greater reach than you are willing to concede.

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I'm not talking to the Italian High Command, I'm speaking to you, and it was you that claimed it was basically the crew's fault that the ship suffered as much as it did. People usually argue using source but are still expected to make their own conclusions. My conclusion is that blaming the crew is an inadequate and convenient explanation. Valient and QE would almost certainly have sunk had they somehow suffered that damage they did while in the same sea conditions as Bismarck was, more so given the class was weak vs. underwater damage.

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Enough water to submerge the forcastle. The TBD system was narrower abreast the turrets vs the machinery spaces due to space limitations which were acute given the bulkiness of the system. This reduced it's efficiency but didn't make it "minor." It still failed which was the point. Designers build in hope and expectation, but reality often is a brutal teacher.

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The original question was could a damaged warship in the stormy North Atlantic conditions Bismarck was faced in steer adequately on props only to escape fate? If steering on props alone was universally "no problem" then warships wouldn't require rudders to begin with.

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I don't recall saying that Littorio was unmaneuverable, the commentary on her design as per Garzke offered a good answer to your earlier question on why would the Germans (not to metion other nations) not build a slew of aux rudders vs a more traditional 2-rudder arragement....that being that the two rudder arrangement allows greater maneuverability vs the arrangement chosen for Littorio. Littorio as mentioned might have avoided more hits had she such an arrangement. Instead redundancy was preferred. Either way, no design FLAW in either ship class, design choice.

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The design folder for that class.

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What do you need them for?

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ORIGINAL: Dili


What those case where it isnt?

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Are you out of your mind? I "clained" that because i have source that said it(do you want a scan?) and makes sense since subsequent torpedo hits the ship class performed well.

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Did you saw what i wrote? seems not. Why it didnt happened later?

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So you don't know that requirement to maneuver for safety is not the same than full performance.

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Your evidence for your conclusion is nil, since you didnt even came up with rudder size comparison or any other source.

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Also seems that you don't even know the reputation of Bismarck, that had a substandart maneuverality and was incapable of maneuvering with minimal safety even with rudder at 0 degrees with engines only. Another evidence of badly tough steering,propeller arrangement and the more i read why not to say the whole back end of the ship. Design Flaw.

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ORIGINAL: Tiornu

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The design folder for that class.

Do you still have the translation?

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What do you need them for?

Good one!

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ORIGINAL: Nikademus

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ORIGINAL: Dili


What those case where it isnt?

You said torpedo hits produce the same hole in the same location every time. Except that it doesn't.

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Are you out of your mind? I "clained" that because i have source that said it(do you want a scan?) and makes sense since subsequent torpedo hits the ship class performed well.

So in other words your saying parrot whatever you read online and don't think for yourself? Subsequent torpedo hits did not all come out rosy for this class either.

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Did you saw what i wrote? seems not. Why it didnt happened later?

Because no Littorio class vessel absorbed 3 torpedo hits at one time after Taranto.

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So you don't know that requirement to maneuver for safety is not the same than full performance.

So your not going to answer the question?

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Your evidence for your conclusion is nil, since you didnt even came up with rudder size comparison or any other source.

Your the first person i've read say that Bismarck's rudder, then rudder(S) were "Tiny" which implies they were inadequate even when functioning. I was curious as to the source of such a claim, thus I asked simply, how do her rudders compare in size to her contemporaries? Your reply is that my "evidence is nil" yet your the one who made the implication.

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Also seems that you don't even know the reputation of Bismarck, that had a substandart maneuverality and was incapable of maneuvering with minimal safety even with rudder at 0 degrees with engines only. Another evidence of badly tough steering,propeller arrangement and the more i read why not to say the whole back end of the ship. Design Flaw.

I know that Bismarck was an excellent seaboat with excellent stability that made her a very good gun platform even in the heavy swells of the Atlantic. This was more than a minor factor in her victory over HMS Hood and in striking PoW several times. You can call her difficulties via properllors alone a flaw though i don't consider it a major one anymore than with her steering arrangements.

any more comments you'd like to make about me?

Art by the amazing Dixie

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Is it just Dili you are inviting to make comments about you Nik, or can we all join in?

PS your Brothers could do with your help with a little rebuilding work that Matrix dropped in our lap...

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ORIGINAL: rtrapasso

Your last paragraph, though, makes my original point: the type XXI's were NOT the "best designed ships of WWII".

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Your opinion that the snorkel had virtually no positive effect on the survivability and the operational opportunities of the U-Boats does surprise me a bit. If snorkels are so useless, why is everybody using them even today, when RADAR performance is several orders of magnitude better than in 1944? But there are people in this forum, ASW practitioners, who can tell you better than I could what the introduction of the snorkel meant for the U-Boats.