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Lucky13
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Another thing comes to mind, which is the more maneuverable ship of the two, in case of evasive maneuvers, which has the faster moving main guns?
Sea battles....
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ToughOmbre
Senior Master Sergeant
Hi all
After what happened to H.M.S. Hood I firmly agree with those who talk of a lucky shot, and wonder about the Bismark's 'excellent' fire control..short comings there may have had her clobbered by a SwordfishThe Hood was sunk because it's commander Admiral Holland had to run a dangerous stage in his otherwise perfect approach to engage the Bismark....a single salvo found it's mark during a window of opportunity.
Hood was a battlecruiser going up against a battleship. No contest. Hood had no adequate armor protection against plunging shellfire.
delcyros
Tech Sergeant
I think I can contribute from my side to the comparison in question.
Both ships are credible powers. The one who assumes it would be an easy match for either Bismarck or West Virginia is probably foolish thinking. However, the single most important aspect is the timeframe. Pointing WV against B requires a timeframe before MAY 1941. At this timeframe, only Bimsarck has limited radar FC, while the first US radar FC was installed on CA Philadelphia in oct. 1941. WV got SC radar later. The advantage in firecontroll during 1941 should be given to Bismarck, as it had the most sophisticated FC system afloat, high mounted with long baselength dublex stereoscopic rangefinders (altough it could be challenged for beeing to complex, there is photographic evidence suggesting some kind of direct muzzle velocity measuring device on the muzzles, kind of 60´s technology, not ww2 era
). If the event would happen between WV and Tirpitz off Norway in, let´s say early 1944, things could change substantially with MK 8 FC on West Virginia (which I personally regard as the best FC in ww2)!!!
If we compare the armour schemes, we should differentiate. At first, there is no ww1 armour scheme on Bismarck. The similarities are of superficial nature (they LOOK identic, but they aren´t). The slope f.e. behind the main belt is also existent on HSF BB´s of ww1 period. But there it is almost half as thick and entirely made from construction grade material! Definetly, in Baden Co, the slope is only for splinter protection and preventing blasts venting upwards and compromising watertight integrity (in case of a torpedo blast in within the TDS). IT WILL NOT STOP PENETRATING PROJECTILES! Baden´s side protection is a thick main belt (13.8"), followed by a coal buncer and a slope against splinters. A huge difference to Bismarcks full armour grade slope, which will deflect belt penetrating projectiles upwards and thus greatly improving Bismarck´s lower immune zone!
Granted, there is one similarity in the two deck deep space between heavy weather deck main armour deck. The armour deck itselfe on Baden (40 mm construction grade material) and Bismarck (80-100mm, full armour grade material) are totally different. Both should blew up projectiles (the weatherdeck initiates the fuze delay (0.025sec. for RN and 0.033sec. for US APC), the idea behind is that most effects of even penetrating projectiles would be outside the embedded vitalia under the main armour deck. Whether or not this works depends on range and trajectory for the guns in question. West Virginia fires a 16"/45 MK V, 2240 lbs MK 5 APC with a 33.6lbs burster charge. The AP Mark 5 projectiles were originally designed to be used in long-range gun actions against japanese ships ("Plan Orange") and for that reason they were to be fired at relatively low muzzle velocities and high gun elevations. These conditions would result in a steeper angle of fall in order to enhance their deck armor penetration capabilities.
Computations based on Nathan Okuns M79APCLC and Fachd 5.8 (at 0 deg. target angle) show that this projectile has pretty good chances to defeat Bismarck´s main armour deck amidships detonate well below it at distances larger than 26.000 yards, when it has an angle of fall of 25.1 deg and a striking velocity of 1507 fps (for an average gun). Note that this range is comparable to the maximum range at which a hit was achieved from a BB in ww2 against a freely moving target (Scharnhorst vs CV Glorious @ 26.400 yards and Warspite vs BB Giulio Cesare @ 26.000 yards)! This is the distance at which Bismarck´s Immune Zone of her embedded vitalia against WV guns ends. The lower end of the immune zone is undefined and only fluke hits may be able to get into Bismarck´s vitals (either a hit BELOW the main belt or a hit which hit´s penetrates the main belt subsequently penetrates the slope on a plate joint). Bismarck´s effective side protection is 320mm KC belt (equals to 322.5mm US Betlehem class A, the type of face hardened armour used on WV, surprisingly much better in stopping power than Iowas armour quality but much worser in terms of inflicting damage to projectiles) + 105mm Wh slope@ 65 deg (= about 202.5mm KC vertical) + 45mm Ww torpedo bulkhead (= 37mm KC).
Simply added together, that equals to nearly 560mm KC stopping power, thus West Virginia should in theory be able to defeat the side protection of Bismarck at distances closer than 6000 yards. At least in case no yawing effects happen! Let´s assume this to be the lower end of the IZ. Bismarck´s IZ amidships against West Virginia therefore is estimated to be around 20.000 yards long, reaching from 6.000 yards out to 26.000 yards (even if the belt itselfe can be defeated at longer range!).
West Virginia´s protection is different. At first and contrary to what one might read in Breyer and elsewhere, the side belt is only 13.5" thick (343mm Betlehem thin chilled class A = 340.3 mm KC in terms of stopping power) and vertical amidships. There is no slope behind but a merely 1" STS splinter deck, laminated over 0.5" mild construction steel (= 1.2" STS single plate in terms of stopping power), which gives no protection against penetrating projectiles or large splinters (2" would be necessary) altough a wide varity of lateral splinters will be contained (the bursting charge of the lighter 15"/52 is 41.4 lbs and thus damage post penetration for Bismarck´s shells is LARGER despite a somehow LIGHTER shell. Shell weight alone means nothing!). The main armour deck of West Virginia, following the All-or-Nothing protective philosophy is a single, thick deck, altough much compromised by the ww1 date. Unlike the splitted but full armour grade deck of Bismarck, West Virgina received several improvements of her armour deck, making it eventually 140mm thick (compare 80mm on Bismarck!). Unfortunately it is not homogeniously but 2" are full grade STS (40´s quality = 1.0), 1.75" are old STS (18´s quality = 0.9) and the lowest 1.75" are even mild construction grade material (18´s steel quality = 0.7). According to the De Marre Nickel Steel formula, the adjusted thickness equals to a single modern STS plate of only 3.4" (86.4mm), not decively more than the 80mm on Bismarck amidships. Any penetration will automaticly harm the vitals below as there is no armoured weatherdeck to initiate the fuze prematurely and the splinter deck is insufficiant to stop the nose pieces as previously mentioned. The armour penetration curves of the 38cmSKC34 taken from GKDos 100 give 120mm homogenious armour deck penetration at 32.808 yards and 80 mm at 25.000 yards. Since the US homogenious armour is substantially better in quality than german homogenious, I estimate that the critical range is to be about 30.000 yards, which puts West Virginia deck vulnarability amidships beyond typical ww2 fighting range (adn thus safe). Her belt however, may be effectively penetrated by Bismarck´s high velocity guns out to 24.000 yards, a considerable distance. Since there is no slope behind, this penetration will define the lower end of West Virginia´s IZ amidships beeing 6.000 yards long, ranging from 24.000 yards to 30.000 yards. Note that in typical fighting distances (10.000-20.000 yards), there is no IZ for West Virginia but a large one for Bismarck! Note also that West Virginia impossibly could exploit it´s advantage at long range with a mere 8-10 Kts speed disadvantage. Bismarck dictates the range.
These are only preliminary notes and should need verifying once more. Changes of the target angle could have drastical effects and penetration is no precise process. The US shell should also be mentioned for beeing virtually indestructable if striking obliquily, altough it lacked a bit penetration power.
Both nations used stable charges (no cordite) and explosions like those on british BC´s at Jutland are unlikely.
Both ships are credible powers. The one who assumes it would be an easy match for either Bismarck or West Virginia is probably foolish thinking. However, the single most important aspect is the timeframe. Pointing WV against B requires a timeframe before MAY 1941. At this timeframe, only Bimsarck has limited radar FC, while the first US radar FC was installed on CA Philadelphia in oct. 1941. WV got SC radar later. The advantage in firecontroll during 1941 should be given to Bismarck, as it had the most sophisticated FC system afloat, high mounted with long baselength dublex stereoscopic rangefinders (altough it could be challenged for beeing to complex, there is photographic evidence suggesting some kind of direct muzzle velocity measuring device on the muzzles, kind of 60´s technology, not ww2 era
). If the event would happen between WV and Tirpitz off Norway in, let´s say early 1944, things could change substantially with MK 8 FC on West Virginia (which I personally regard as the best FC in ww2)!!! If we compare the armour schemes, we should differentiate. At first, there is no ww1 armour scheme on Bismarck. The similarities are of superficial nature (they LOOK identic, but they aren´t). The slope f.e. behind the main belt is also existent on HSF BB´s of ww1 period. But there it is almost half as thick and entirely made from construction grade material! Definetly, in Baden Co, the slope is only for splinter protection and preventing blasts venting upwards and compromising watertight integrity (in case of a torpedo blast in within the TDS). IT WILL NOT STOP PENETRATING PROJECTILES! Baden´s side protection is a thick main belt (13.8"), followed by a coal buncer and a slope against splinters. A huge difference to Bismarcks full armour grade slope, which will deflect belt penetrating projectiles upwards and thus greatly improving Bismarck´s lower immune zone!
Granted, there is one similarity in the two deck deep space between heavy weather deck main armour deck. The armour deck itselfe on Baden (40 mm construction grade material) and Bismarck (80-100mm, full armour grade material) are totally different. Both should blew up projectiles (the weatherdeck initiates the fuze delay (0.025sec. for RN and 0.033sec. for US APC), the idea behind is that most effects of even penetrating projectiles would be outside the embedded vitalia under the main armour deck. Whether or not this works depends on range and trajectory for the guns in question. West Virginia fires a 16"/45 MK V, 2240 lbs MK 5 APC with a 33.6lbs burster charge. The AP Mark 5 projectiles were originally designed to be used in long-range gun actions against japanese ships ("Plan Orange") and for that reason they were to be fired at relatively low muzzle velocities and high gun elevations. These conditions would result in a steeper angle of fall in order to enhance their deck armor penetration capabilities.
Computations based on Nathan Okuns M79APCLC and Fachd 5.8 (at 0 deg. target angle) show that this projectile has pretty good chances to defeat Bismarck´s main armour deck amidships detonate well below it at distances larger than 26.000 yards, when it has an angle of fall of 25.1 deg and a striking velocity of 1507 fps (for an average gun). Note that this range is comparable to the maximum range at which a hit was achieved from a BB in ww2 against a freely moving target (Scharnhorst vs CV Glorious @ 26.400 yards and Warspite vs BB Giulio Cesare @ 26.000 yards)! This is the distance at which Bismarck´s Immune Zone of her embedded vitalia against WV guns ends. The lower end of the immune zone is undefined and only fluke hits may be able to get into Bismarck´s vitals (either a hit BELOW the main belt or a hit which hit´s penetrates the main belt subsequently penetrates the slope on a plate joint). Bismarck´s effective side protection is 320mm KC belt (equals to 322.5mm US Betlehem class A, the type of face hardened armour used on WV, surprisingly much better in stopping power than Iowas armour quality but much worser in terms of inflicting damage to projectiles) + 105mm Wh slope@ 65 deg (= about 202.5mm KC vertical) + 45mm Ww torpedo bulkhead (= 37mm KC).
Simply added together, that equals to nearly 560mm KC stopping power, thus West Virginia should in theory be able to defeat the side protection of Bismarck at distances closer than 6000 yards. At least in case no yawing effects happen! Let´s assume this to be the lower end of the IZ. Bismarck´s IZ amidships against West Virginia therefore is estimated to be around 20.000 yards long, reaching from 6.000 yards out to 26.000 yards (even if the belt itselfe can be defeated at longer range!).
West Virginia´s protection is different. At first and contrary to what one might read in Breyer and elsewhere, the side belt is only 13.5" thick (343mm Betlehem thin chilled class A = 340.3 mm KC in terms of stopping power) and vertical amidships. There is no slope behind but a merely 1" STS splinter deck, laminated over 0.5" mild construction steel (= 1.2" STS single plate in terms of stopping power), which gives no protection against penetrating projectiles or large splinters (2" would be necessary) altough a wide varity of lateral splinters will be contained (the bursting charge of the lighter 15"/52 is 41.4 lbs and thus damage post penetration for Bismarck´s shells is LARGER despite a somehow LIGHTER shell. Shell weight alone means nothing!). The main armour deck of West Virginia, following the All-or-Nothing protective philosophy is a single, thick deck, altough much compromised by the ww1 date. Unlike the splitted but full armour grade deck of Bismarck, West Virgina received several improvements of her armour deck, making it eventually 140mm thick (compare 80mm on Bismarck!). Unfortunately it is not homogeniously but 2" are full grade STS (40´s quality = 1.0), 1.75" are old STS (18´s quality = 0.9) and the lowest 1.75" are even mild construction grade material (18´s steel quality = 0.7). According to the De Marre Nickel Steel formula, the adjusted thickness equals to a single modern STS plate of only 3.4" (86.4mm), not decively more than the 80mm on Bismarck amidships. Any penetration will automaticly harm the vitals below as there is no armoured weatherdeck to initiate the fuze prematurely and the splinter deck is insufficiant to stop the nose pieces as previously mentioned. The armour penetration curves of the 38cmSKC34 taken from GKDos 100 give 120mm homogenious armour deck penetration at 32.808 yards and 80 mm at 25.000 yards. Since the US homogenious armour is substantially better in quality than german homogenious, I estimate that the critical range is to be about 30.000 yards, which puts West Virginia deck vulnarability amidships beyond typical ww2 fighting range (adn thus safe). Her belt however, may be effectively penetrated by Bismarck´s high velocity guns out to 24.000 yards, a considerable distance. Since there is no slope behind, this penetration will define the lower end of West Virginia´s IZ amidships beeing 6.000 yards long, ranging from 24.000 yards to 30.000 yards. Note that in typical fighting distances (10.000-20.000 yards), there is no IZ for West Virginia but a large one for Bismarck! Note also that West Virginia impossibly could exploit it´s advantage at long range with a mere 8-10 Kts speed disadvantage. Bismarck dictates the range.
These are only preliminary notes and should need verifying once more. Changes of the target angle could have drastical effects and penetration is no precise process. The US shell should also be mentioned for beeing virtually indestructable if striking obliquily, altough it lacked a bit penetration power.
Both nations used stable charges (no cordite) and explosions like those on british BC´s at Jutland are unlikely.
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- #24
Lucky13
Forum Mascot
WOW! Very interesting delcyros! 8) 
Seawitch
Airman 1st Class
Now not so simple! Hood was the Worlds largest warship, her construction was dated, that was noted after Jutland and her construction was briefly halted while some stock was taken even then and modernisation was ever put of between the wars by her diplomatic duties if thats the right word, and she was to tied down by the war to be released for them.
If she was 'no contest' do you really think they would have put a Capital ship right where it's destruction was obvious?
Like I said, Admiral Hollands manoeuvres where to engage the Bismark in a way that would force the fire to be exchanged at a low trajectory that served the Hoods purpose, but he had to dash through a dangerous area to that first, it was in this window of opportunity that the Bismark was so lucky as to find a weak spot with a single Salvo.
Great post Del, as usual. Wondering when you were going to jump into this one.
Sounds like it boils down to the B having the speed to dictate the fight with a generous immune zone via superior armor, superior FC and rate of fire. Looks like a bad day for the WeeVee.
Sounds like it boils down to the B having the speed to dictate the fight with a generous immune zone via superior armor, superior FC and rate of fire. Looks like a bad day for the WeeVee.
delcyros
Tech Sergeant
Seawitch is right.
Hood by far isn´t as bad as DS makes look her to be. As a matter of fact, Hood was considered the best solution for a Battleship in the interwar period. She had a good balance between high speed, high hitting power and a high degree of protection. Just like the later Iowas on the expense of large displacement. Altough, while debatable, Hood most probably did not fell victim to plunging fire from Bismarck (at the given distance the angle of fall of the german 15" round is to small to indicate deck penetration) but instead fell victim to an ordinary (upper) belt penetration, which luckily ended somewhere in within the vitals.
At the distance she blew up, she already left the lower end of her immune zone against the 38cm round.
Hood by far isn´t as bad as DS makes look her to be. As a matter of fact, Hood was considered the best solution for a Battleship in the interwar period. She had a good balance between high speed, high hitting power and a high degree of protection. Just like the later Iowas on the expense of large displacement. Altough, while debatable, Hood most probably did not fell victim to plunging fire from Bismarck (at the given distance the angle of fall of the german 15" round is to small to indicate deck penetration) but instead fell victim to an ordinary (upper) belt penetration, which luckily ended somewhere in within the vitals.
At the distance she blew up, she already left the lower end of her immune zone against the 38cm round.
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Lucky13
Forum Mascot
Am I correct thinking that West Virginia didn't get radar until after Pearl Harbor when she was damaged and later modernized?
mkloby
Senior Master Sergeant
My goodness Del - do you actually have all these stats and figures packed away in your brain?
I have read that the Hood's percentage of armor roughly equaled the percentage on the QE class.
Regarding your post above - I have a question. It seems from everything I read that Bismark did have an armor layout similar to Germany's WWI dreadnoughts, but that quality of the steel was higher and there was more thickness. Your post seems to also say this, unless I'm misunderstanding (I'm no engineer so some of your fancy numbers and such look like wingdings to me!).
My question is: how is the effectiveness of that armor scheme compared to contemporary battleships with different armor schemes?
I have read that the Hood's percentage of armor roughly equaled the percentage on the QE class.
Regarding your post above - I have a question. It seems from everything I read that Bismark did have an armor layout similar to Germany's WWI dreadnoughts, but that quality of the steel was higher and there was more thickness. Your post seems to also say this, unless I'm misunderstanding (I'm no engineer so some of your fancy numbers and such look like wingdings to me!).
My question is: how is the effectiveness of that armor scheme compared to contemporary battleships with different armor schemes?
delcyros
Tech Sergeant
The armour scheme of B. should be considered in context to the thread scenario and environmental issues. The North Atlantic is quite different to the Pacific. Had Bismarck been designed with the Pacific in mind, she undoubtly would have looked different.
As B.Hoyer in 1941 wrote, the stage of projectiles and their relative armour penetration capabilities had reached a point where no practical amount of armour could provide protection at the expected battle ranges (which were believed to be 10.000 yrds to 25.000 yards for the North Atlantic) so they needed to include the main armour deck into the side protection system somehow. An elegant solution as it turned out.
If You compare this scheme with the pocket BB´s, you will notice differences:
The PBB (also All-or-Nothing) have the armour deck on top of the main belt, which is inclined for additional stopping power, much like ww2 US and IJN BB´s.
The step to the heavy slope (not known in ww1) was the result of extended testings on hull segments, which prooved that the new protective layout would provide good protection, while in the meantime it would allow large areas to be covered by armour, an important requirement for such a small navy as the DKM.
Bismarck was not designed to be unsinkable. Rather it was designed to fight another day, which was in congruence with naval doctrines of Germany in ww2. Unfortunately, while in such a situation historically, the loss of steering controll prevented that B. could return home, while the protective system worked as expected at the final battle.
The flip side of the coin is that this system consumes a lot of weight. Much more than AoN. That made the reduction in thicknesses of the exposed vitalia (CT, barbettes, turrets) necessary. Altough at the conditions of her final battle, not even Yamato scale armour would have helped her. The exposed vitals were wrecked in quick succession but the watertight integrity, the stability and the buoyancy reserve remained less touched.
Comparing this with other schemes is difficult as other schemes preferred other philosophies. The french for example, have a very balanced AoN scheme, much like US BB´s. But a single penetrating hit settled Jean Beart´s stern at Casablanca (in deep water she would have sunk!), due to the low buoyancy reserve. The thick turret protection was compromised by a single (non penetrating) shell hit, which disabled the only remaining turret.
The IJN Yamato, arguably the best protected BB ever made (at least for the exposed vitals), had problems in the rivetting structures, the joints and (again) buoyoncy reserve. You won´t find a BB having no problems.
The US fast BB´s Iowa SD have a significant problem in the joint between upper lower main armour belt. The belt is innermounted and 19 degrees inclined, thus a projectile may hit the lower (homogenious) class B belt without making extensive underwater travel first. Also even non penetrating, a shell doesn´t disappears on the belt, it get´s deflected downwards into the TDS, compromising the watertight integrity and causing off center flooding (probably the reason why innermounted belts were dropped by the RN, the DKM and the USN in her Montana class design). However, french, IJN and USN BB´s were optimized for long range encounters in good weather, a probable scenario for the med and Pacific.
As B.Hoyer in 1941 wrote, the stage of projectiles and their relative armour penetration capabilities had reached a point where no practical amount of armour could provide protection at the expected battle ranges (which were believed to be 10.000 yrds to 25.000 yards for the North Atlantic) so they needed to include the main armour deck into the side protection system somehow. An elegant solution as it turned out.
If You compare this scheme with the pocket BB´s, you will notice differences:
The PBB (also All-or-Nothing) have the armour deck on top of the main belt, which is inclined for additional stopping power, much like ww2 US and IJN BB´s.
The step to the heavy slope (not known in ww1) was the result of extended testings on hull segments, which prooved that the new protective layout would provide good protection, while in the meantime it would allow large areas to be covered by armour, an important requirement for such a small navy as the DKM.
Bismarck was not designed to be unsinkable. Rather it was designed to fight another day, which was in congruence with naval doctrines of Germany in ww2. Unfortunately, while in such a situation historically, the loss of steering controll prevented that B. could return home, while the protective system worked as expected at the final battle.
The flip side of the coin is that this system consumes a lot of weight. Much more than AoN. That made the reduction in thicknesses of the exposed vitalia (CT, barbettes, turrets) necessary. Altough at the conditions of her final battle, not even Yamato scale armour would have helped her. The exposed vitals were wrecked in quick succession but the watertight integrity, the stability and the buoyancy reserve remained less touched.
Comparing this with other schemes is difficult as other schemes preferred other philosophies. The french for example, have a very balanced AoN scheme, much like US BB´s. But a single penetrating hit settled Jean Beart´s stern at Casablanca (in deep water she would have sunk!), due to the low buoyancy reserve. The thick turret protection was compromised by a single (non penetrating) shell hit, which disabled the only remaining turret.
The IJN Yamato, arguably the best protected BB ever made (at least for the exposed vitals), had problems in the rivetting structures, the joints and (again) buoyoncy reserve. You won´t find a BB having no problems.
The US fast BB´s Iowa SD have a significant problem in the joint between upper lower main armour belt. The belt is innermounted and 19 degrees inclined, thus a projectile may hit the lower (homogenious) class B belt without making extensive underwater travel first. Also even non penetrating, a shell doesn´t disappears on the belt, it get´s deflected downwards into the TDS, compromising the watertight integrity and causing off center flooding (probably the reason why innermounted belts were dropped by the RN, the DKM and the USN in her Montana class design). However, french, IJN and USN BB´s were optimized for long range encounters in good weather, a probable scenario for the med and Pacific.
