Increasing Bismarck's Armor By 50% Would Make a Difference?

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Garyt
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Re: Increasing Bismarck's Armor By 50% Would Make a Differen

Post by Garyt »

How far into the attack was that, Mostly Harmless?
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Re: Increasing Bismarck's Armor By 50% Would Make a Differen

Post by Steve Crandell »

Mostlyharmless wrote:
Garyt wrote:
Yamato had an auxiliary rudder, but in testing it wasn't able to turn the ship.
Funny how much luck plays a role. Between them the Yamato and Musahi were hit by 30 or so torpedoes - and not one to my knowledge took the rudder out.
During her final sortie, Yamato suffered a torpedo hit or hits aft which flooded the auxiliary rudder steering room. The auxiliary rudder was stuck hard to port so that the ship could no longer make turns to starboard.
I think that is the first time I've heard of that. I remember reading that in tests with the main rudder admidships the auxiliary rudder was unable to turn the ship at all. One would think that jamming the latter wouldn't effect the ship much, let alone completely prevent the main rudder from turning the ship.
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Re: Increasing Bismarck's Armor By 50% Would Make a Differen

Post by Mostlyharmless »

There may be some problems in establishing exactly what occurred. After all we do not have Yamato's logs although some information was probably officially noted after questioning survivors. Even those notes may not have survived the destruction of records following the Japanese Surrender. Normally memoires, especially rather literary memoires, have lower weight than most primary sources. However, Yoshida Mitsuru was on the bridge at the time, so I am going to believe him https://books.google.co.uk/books?id=T1K ... 22&f=false and I would anyway recommend his account as an interesting read.
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Re: Increasing Bismarck's Armor By 50% Would Make a Differen

Post by Paul L »

Quick rough and dirty for a Bismarck with +50% armor

19,500 tons ---> 28,800 tons by upping CT Front Turret etc to 500mm and extending main belt to 230m 85% of hull length which has to reach 270m and bulge width to 40m. Net impact max displacement rises to something over 70k and speed on 150,000hp down to > 27 knots. To keep endurance at 8200nm requires 10,000 tons fuel.

Armored steel invested in KM from 1934-1940 was ~ 88,000 tons so two such Bismarck's would use 2/3 of the armor, while "The Twins" at 14kt each would use up the other 1/3 leaving nothing for Hipper class cruisers or Graf Zeppelin . Total construction tonnage would be 218kt which would be the same as TWINS + 2x BIS + Hip & Bluch

Bismarck+ 50, Deutschland Battleship laid down 1936 (Engine 1937)

Displacement:
57,811 t light; 60,474 t standard; 66,095 t normal; 70,592 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(917.86 ft / 885.83 ft) x 118.11 ft (Bulges 131.23 ft) x (30.15 / 32.10 ft)
(279.76 m / 270.00 m) x 36.00 m (Bulges 40.00 m) x (9.19 / 9.78 m)


Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 12.6" / 320 mm 787.40 ft / 240.00 m 19.69 ft / 6.00 m
Ends: Unarmoured
Upper: 6.89" / 175 mm 563.32 ft / 171.70 m 13.12 ft / 4.00 m
Main Belt covers 137 % of normal length

- Torpedo Bulkhead:
5.12" / 130 mm 754.59 ft / 230.00 m 45.93 ft / 14.00 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 18.1" / 460 mm 8.66" / 220 mm 14.2" / 360 mm
2nd: 4.72" / 120 mm 4.33" / 110 mm 4.33" / 110 mm
3rd: 0.79" / 20 mm 0.79" / 20 mm 0.79" / 20 mm

- Protected deck - multiple decks: 7.87" / 200 mm For and Aft decks
Forecastle: 3.94" / 100 mm Quarter deck: 3.94" / 100 mm

- Conning towers: Forward 19.69" / 500 mm, Aft 0.00" / 0 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 3 shafts, 150,104 shp / 111,978 Kw = 27.66 kts
Range 8,252nm at 19.00 kts
Bunker at max displacement = 10,119 tons

Complement:
2,060 - 2,679

Cost:
£22.176 million / $88.705 million



Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
111,576 lbs / 50,610 Kg = 66.6 x 15.0 " / 380 mm shells or 38.9 torpedoes
Stability (Unstable if below 1.00): 1.46
Metacentric height 12.4 ft / 3.8 m
Roll period: 15.7 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.16
Seaboat quality (Average = 1.00): 1.00


Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 20.00 %, 26.64 ft / 8.12 m, 17.13 ft / 5.22 m
- Forward deck: 30.00 %, 17.13 ft / 5.22 m, 17.16 ft / 5.23 m
- Aft deck: 30.00 %, 17.13 ft / 5.22 m, 17.13 ft / 5.22 m
- Quarter deck: 20.00 %, 17.13 ft / 5.22 m, 20.08 ft / 6.12 m
- Average freeboard: 18.19 ft / 5.54 m
Ship tends to be wet forward
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Re: Increasing Bismarck's Armor By 50% Would Make a Differen

Post by Paul L »

OK for comparison here would be the Bismarck with 1/3 less armor....essentially a Scharnhorst BB with 6 x 15" guns and an armor base around 14kt much like the Twins. To reduce armor had to reduce width to Twins levels and replace all secondaries with 12 twin 4" flak. Bunkerage is reduced to 5500 tons which = 7000/19 [by Spring sharp]. Sea keeping is average for top speed of 30.7knots, however strength is POOR compared to Bismarck and Super Bismarck....the ship would take about 2/3 the beating it did historically, however it might have been able to out run the HOOD and Prince of Whales at DS and escape into North Atlantic untouched, which would have been a better outcome anyway.

Most important outcome based on 88kt armor & 240kt warship construction , allows "The Twins" , both Bismarck's , Graf Zeppelin plus 3 of 5 Hipper class to be completed by end of 1940. In 1941 there is sufficient armor and warship construction to complete another Hipper class plus extra work to remove 11" batteries and the bow/stern of both 'The Twins'. In 1942 there is sufficient 15" guns ; armor and warship construction tonnage to recommissions both of "The Twins" with 6 x 15" guns and the last Hipper class Cruiser, but work on Destroyers and TB would have to be delayed by a year or two.


Bismarck @ 2/3

Displacement:
28,432 t light; 30,096 t standard; 33,234 t normal; 35,744 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(808.48 ft / 771.00 ft) x 98.43 ft x (23.95 / 25.48 ft)
(246.42 m / 235.00 m) x 30.00 m x (7.30 / 7.76 m)

Armament:
6 - 15.08" / 383 mm 49.0 cal guns - 1,805.67lbs / 819.04kg shells, 150 per gun
Breech loading guns in turret on barbette mounts, 1934 Model
3 x Twin mounts on centreline ends, evenly spread
2 raised mounts - superfiring
12 - 4.13" / 105 mm 65.0 cal guns - 39.16lbs / 17.76kg shells, 150 per gun
Anti-air guns in deck and hoist mounts, 1934 Model
6 x Twin mounts on sides, evenly spread
12 - 4.13" / 105 mm 65.0 cal guns - 39.16lbs / 17.76kg shells, 150 per gun
Anti-air guns in deck and hoist mounts, 1933 Model
6 x Twin mounts on sides, evenly spread
6 raised mounts
16 - 1.46" / 37.0 mm 90.0 cal guns - 1.79lbs / 0.81kg shells, 1,000 per gun
Anti-air guns in deck mounts, 1930 Model
8 x Twin mounts on centreline, aft deck forward
8 double raised mounts
16 - 0.79" / 20.0 mm 65.0 cal guns - 0.27lbs / 0.12kg shells, 1,000 per gun
Anti-air guns in deck mounts, 1930 Model
8 x Twin mounts on centreline, evenly spread
8 double raised mounts
Weight of broadside 11,807 lbs / 5,355 kg

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 12.6" / 320 mm 524.93 ft / 160.00 m 13.12 ft / 4.00 m
Ends: Unarmoured
Upper: 5.91" / 150 mm 524.93 ft / 160.00 m 13.12 ft / 4.00 m
Main Belt covers 105 % of normal length

- Torpedo Bulkhead:
1.77" / 45 mm 492.13 ft / 150.00 m 45.93 ft / 14.00 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 13.8" / 350 mm 5.91" / 150 mm 11.8" / 300 mm
2nd: 0.79" / 20 mm 0.79" / 20 mm 0.79" / 20 mm
3rd: 0.79" / 20 mm 0.79" / 20 mm 0.79" / 20 mm

- Protected deck - multiple decks: 5.91" / 150 mm For and Aft decks

- Conning towers: Forward 13.78" / 350 mm, Aft 0.00" / 0 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 3 shafts, 150,792 shp / 112,491 Kw = 30.70 kts
Range 7,000nm at 19.00 kts
Bunker at max displacement = 5,647 tons

Complement:
1,229 - 1,599

Cost:
£14.846 million / $59.383 million

Distribution of weights at normal displacement:
Armament: 2,268 tons, 6.8 %
Armour: 13,784 tons, 41.5 %
- Belts: 5,379 tons, 16.2 %
- Torpedo bulkhead: 1,482 tons, 4.5 %
- Armament: 2,195 tons, 6.6 %
- Armour Deck: 4,422 tons, 13.3 %
- Conning Tower: 307 tons, 0.9 %
Machinery: 4,179 tons, 12.6 %
Hull, fittings & equipment: 7,957 tons, 23.9 %
Fuel, ammunition & stores: 4,802 tons, 14.4 %
Miscellaneous weights: 243 tons, 0.7 %
- Hull below water: 43 tons
- On freeboard deck: 180 tons
- Above deck: 20 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
30,782 lbs / 13,963 Kg = 18.0 x 15.1 " / 383 mm shells or 6.1 torpedoes
Stability (Unstable if below 1.00): 1.20
Metacentric height 6.8 ft / 2.1 m
Roll period: 15.9 seconds
Steadiness - As gun platform (Average = 50 %): 54 %
- Recoil effect (Restricted arc if above 1.00): 0.61
Seaboat quality (Average = 1.00): 1.08

Hull form characteristics:
Hull has rise forward of midbreak,
an extended bulbous bow and a round stern
Block coefficient (normal/deep): 0.640 / 0.647
Length to Beam Ratio: 7.83 : 1
'Natural speed' for length: 27.77 kts
Power going to wave formation at top speed: 53 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 40.00 degrees
Stern overhang: 9.68 ft / 2.95 m
Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 28.00 %, 33.14 ft / 10.10 m, 23.33 ft / 7.11 m
- Forward deck: 28.00 %, 23.33 ft / 7.11 m, 23.36 ft / 7.12 m
- Aft deck: 22.00 %, 23.33 ft / 7.11 m, 23.33 ft / 7.11 m
- Quarter deck: 22.00 %, 23.33 ft / 7.11 m, 26.28 ft / 8.01 m
- Average freeboard: 24.75 ft / 7.55 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 95.0 %
- Above water (accommodation/working, high = better): 208.3 %
Waterplane Area: 57,601 Square feet or 5,351 Square metres
Displacement factor (Displacement / loading): 97 %
Structure weight / hull surface area: 112 lbs/sq ft or 545 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.59
- Longitudinal: 0.68
- Overall: 0.59
Caution: Hull subject to strain in open-sea
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent
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RF
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Re: Increasing Bismarck's Armor By 50% Would Make a Differen

Post by RF »

Paul L wrote:OK for comparison here would be the Bismarck with 1/3 less armor....essentially a Scharnhorst BB with 6 x 15" guns and an armor base around 14kt much like the Twins.
Then the consideration could be extended to building three ships of this class rather than two.

Another point from the analysis here - why not build more panzerschiffe rather than Hipper class cruisers?
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Re: Increasing Bismarck's Armor By 50% Would Make a Differen

Post by Paul L »

RF wrote:
Paul L wrote:OK for comparison here would be the Bismarck with 1/3 less armor....essentially a Scharnhorst BB with 6 x 15" guns and an armor base around 14kt much like the Twins.
Then the consideration could be extended to building three ships of this class rather than two.

Another point from the analysis here - why not build more panzerschiffe rather than Hipper class cruisers?

Weeeeellll that was in fact was the original plan. But it was not what Hitler wanted.

Original naval plan 1932 had Panzerschiffe D-E-F-G-H-J ; all as variants of the earlier PBS . Stretched to >18,000 tons with a third triple 11"C28 turret and belt armor up to 5". The front turret and CT were to reach 200mm and the deck armor was 20mm plus 50mm. So the belt protection would be 120 mm plus 50mm slopes and 45mm Torpedo bulkhead. Combined that's about 8-10" depending on the size of the attacking projectile.

While Diesel power increased to < 80K , this was only sufficient to ensure 29knots sustained speed plus the enormous endurance of the PBS. That was decidedly an anti RN warship and the mission was to succeed were the 1914 Falklands raids failed- IE raid and come home. Hitler wanted none of this and planned to scrub all construction in favor of pure coastal defense fleet with ability to dominate the Baltics and North Sea.

In what seems like a desperate move Admiral Raeder convinced Hitler that these warships were not being built to threaten the UK but to defeat a Franco Polish naval threat. He quickly changed the 6 PBS order to instead include 3 x 35kt BB each with 14" guns plus a couple of cruisers [Type unspecified at this time - but some private venture drawings reveal a mini Hipper cruiser with two Seaplane catapults plus 5 triple 6" guns] . Hitler accepted this but rejected the 14" guns and changed them back to the 11"C28 guns.

There then followed a period of a couple of years when Hitler took power and the navy chiefs went nuts upping the ante . Within 19 redesigns they ended up with the Twins as we know of from history. Some one even uncovered a document that insists that the Bismarck is committed to 8 x 14" guns as of April 1935 [15 months before keel laid down] , when no such gun existed or was planed for, and yet 15" and 16" guns were already designed for warships that hadn't even been planned for.

The word is that the beginning's of the Z plan emerged out of these changes.

A very confusing mess.
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Re: Increasing Bismarck's Armor By 50% Would Make a Differen

Post by RF »

Paul L wrote: A very confusing mess.
All reflecting the total lack of strategic vision - which ultimately led to Hitler's downfall.

The Anglo-German Naval Agreement of 1934 was a trump card that Hitler missed. He could have used it to build a KM to 35% the strength of the RN with full British approval - after all they signed the agreement.
With construction starting in 1935 he could have built up his navy for a war starting around 1941 or 1942, in the meantime using Franco/British appeasement policies to gobble up Austria, the Sudetenland, Memel, parts of Poland plus Danzig, perhaps even Eupen/Malmedy from Belgium (as part of a deal for Belgian neutrality) all without firing a shot. The British would even have given him Togo and Cameroon back as African colonies.

Fortunately for mankind dictators and melogomaniacs tend to be pretty thick.
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Re: Increasing Bismarck's Armor By 50% Would Make a Differen

Post by Dave Saxton »

Paul L wrote: Some one even uncovered a document that insists that the Bismarck is committed to 8 x 14" guns as of April 1935 [15 months before keel laid down] , when no such gun existed or was planed for, and yet 15" and 16" guns were already designed for warships that hadn't even been planned for.
Beyer compiled the documents revealing the design history of the Bismarck class in his 1991 Bismarck 50th anniversary book. The Bismarck was indeed originally envisioned with the Krupp 35cm/L54 gun. 35cm =13.8". The 35cm, 38cm, and 40.6cm were all designed by Krupp at the same time. Tests revealed the 35cm could defeat the Dunkerque's sloped belt all the way out to 34km. But the 38cm/L52 tested even better and the 40.6cm not much better than that.

Why wasn't Scharnhorst and Gneisenau equipped with the 35cm instead of 28cm? The answer lies with the fact that 38cm twin mount is about the same size and weight as the 28cm triple.
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.
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Re: Increasing Bismarck's Armor By 50% Would Make a Differen

Post by Dave Saxton »

RF wrote:Fortunately for mankind dictators and melogomaniacs tend to be pretty thick.
Indeed.
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.
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Re: Increasing Bismarck's Armor By 50% Would Make a Differen

Post by Mostlyharmless »

Looking back over the thread, there was an unanswered question about the Littorio Class.
Thoddy wrote:
acccording to Bagnasco, main rudder was jamed in Vitorio Veneto by the explosion
wich position
did you have an transversal drawing of rudderequipment (rudders and machinery)
I can't actually give the required data. However, Wikipedia has a nice picture http://upload.wikimedia.org/wikipedia/c ... Roma55.jpg that shows the arrangement and Bagnasco, page 96, tells us that the auxiliary rudders were 25 metres forward of the main rudder.

The torpedo hit on Vittorio Veneto at Matapan seems to have been forward of the port auxiliary rudder judging from the illustration on page 334 of Bagnasco and heavily damaged the outer port shaft and the port auxiliary rudder. There is also a picture on Italian Wikipedia http://upload.wikimedia.org/wikipedia/i ... tapan1.jpg. The description may suggest that VV lost steerage way rather than that the main rudder was damaged although the power for the main rudder may have been temporarily lost. All the shafts were stopped after the hit. Only the outer starboard shaft could be quickly restarted. The inner port shaft was out of action and there were problems with the lubrication of the inner starboard shaft although those could be solved.

Bagnasco speculates on page 294 that Bismarck might had escaped in May 1941 had she had the Littorio Class' rudder arrangement.
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Re: Increasing Bismarck's Armor By 50% Would Make a Differen

Post by Mostlyharmless »

One of the most “possible” improvements to Bismarck would have been to add a lower belt. If we imagine adding a duplicate of the upper belt below the main belt, we know it would cost about 1,000 tons. I can imagine that replacing Bismarck's 150 mm and 105 mm batteries by King George V's 5.25 inch battery would save about the same weight.

I am not sure if a 145 mm belt would have stopped the hit from Prince of Wales. If it hit Bismarck about 2,5 metres below the waterline, the shell must have travelled at least 8 metres through the water and possibly more as shells tend to deflect upwards. Thus PoW's shell must have travelled 22-25 calibres underwater unless the waves were very helpful. The Japanese Type 91 shells only lost half their velocity over 100 calibres. However, the RN shell may have been yawed more than a Type 91 and may have lost velocity more rapidly. In conclusion, we have a possibly strongly yawed shell hitting a 145 mm plate at 30-40 degrees and at 350-400 metres per second.
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Re: Increasing Bismarck's Armor By 50% Would Make a Differen

Post by Paul L »

Dave Saxton wrote:
Paul L wrote: Some one even uncovered a document that insists that the Bismarck is committed to 8 x 14" guns as of April 1935 [15 months before keel laid down] , when no such gun existed or was planed for, and yet 15" and 16" guns were already designed for warships that hadn't even been planned for.
Beyer compiled the documents revealing the design history of the Bismarck class in his 1991 Bismarck 50th anniversary book. The Bismarck was indeed originally envisioned with the Krupp 35cm/L54 gun. 35cm =13.8". The 35cm, 38cm, and 40.6cm were all designed by Krupp at the same time. Tests revealed the 35cm could defeat the Dunkerque's sloped belt all the way out to 34km. But the 38cm/L52 tested even better and the 40.6cm not much better than that.

Why wasn't Scharnhorst and Gneisenau equipped with the 35cm instead of 28cm? The answer lies with the fact that 38cm twin mount is about the same size and weight as the 28cm triple.
Dave not saying you are wrong but the recoil impulse of 2 x 15" guns is more than 3 x 11"C34 guns.
I make it
~ 656mt/second for each 15" gun and 197mt/sec for each 11"c34 gun.


So I would think if you want Bismarck guns you need a Bismarck turret [IE 1050 tons vs 750 tons] . The Barbettes are the same but the ships needs new bow section at least. Major work!

Also when you say 35cm was tested against Dunkerque's armor, How was that done without a 14" gun?
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Re: Increasing Bismarck's Armor By 50% Would Make a Differen

Post by Dave Saxton »

Paul L wrote:Also when you say 35cm was tested against Dunkerque's armor, How was that done without a 14" gun?
They had a 35cm/L54 gun.
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.
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Re: Increasing Bismarck's Armor By 50% Would Make a Differen

Post by Dave Saxton »

Mostlyharmless wrote:One of the most “possible” improvements to Bismarck would have been to add a lower belt. If we imagine adding a duplicate of the upper belt below the main belt, we know it would cost about 1,000 tons. I can imagine that replacing Bismarck's 150 mm and 105 mm batteries by King George V's 5.25 inch battery would save about the same weight.

I am not sure if a 145 mm belt would have stopped the hit from Prince of Wales. If it hit Bismarck about 2,5 metres below the waterline, the shell must have travelled at least 8 metres through the water and possibly more as shells tend to deflect upwards. Thus PoW's shell must have travelled 22-25 calibres underwater unless the waves were very helpful. The Japanese Type 91 shells only lost half their velocity over 100 calibres. However, the RN shell may have been yawed more than a Type 91 and may have lost velocity more rapidly. In conclusion, we have a possibly strongly yawed shell hitting a 145 mm plate at 30-40 degrees and at 350-400 metres per second.
What would a lower belt do to the TDS?

The Baron wrote:
The second hit struck beneath the armored belt along side compartment XIV and exploded against the torpedo bulkhead. It caused flooding in the forward port generator room and power station number 4, and shattered bulkheads between that room and the two adjacent ones, the port number 2 boiler room and the auxiliary boiler room. Later it was discovered that this hit had ripped up several fuel tanks in the storage and double bottom...the damage repair parties stuffed the shattered bulkheads in the port number 2 boiler room and the auxiliary boiler room with hammocks...
Three things are indicated:
1) The hit was deep. Deep enough to reach the double bottom with its effects.
2) The shell itself did not penetrate the vitals.
3) The damages came from high velocity splinters when the shell detonated within the wing tank area.

The British fuse timing was nominally 0.025 seconds. This means it would have traveled about 8-11 meters after striking the water even if it retained 350-400 M/s velocity, unless it was dud. This further indicates that it likey exploded within the wing tanks before reaching the torpedo bulkhead.

A 145mm Ww inner bulkhead as opposed to the 45mm Ww bulkhead may have helped stop the splinters, but the question remains what the side effects would have been in terms of protection from torpedoes and mines.
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.
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