Battleships

[Logi]

This causes a curious look on my face though:

Listed SS belt thickness / cos(angle) = LOS thickness (Not recommended as it oversimplifies things)

This is absolutely true if you want to calculate the thickness of armor of an angled plate at 90degrees LoS which itself has uniform thickness, is it not?

Yes, perhaps I should have been a bit more specific. LOS thickness and effective thickness are not the same thing. Effective thickness depends also on the weight and diameter of the shell impacting it. That's why using LOS thickness as a subsittue oversimplifies things.

That is what I meant.

[Delta Force]

The latest version of the ship. One of the big changes I made was to make the entire ship protected by the deck armor and TDS, and I also added a 2 inch armor belt to the ends of the ship, to help protect against 5 inch shells and shrapnel, and also to increase the strength of the hull.

15 Inch Battleshipv3, CSA Battleship laid down 1920

Displacement:
   35,000 t light; 36,920 t standard; 39,388 t normal; 41,362 t full load

Dimensions: Length overall / water x beam x draught
   721.78 ft / 721.78 ft x 104.99 ft (Bulges 118.11 ft) x 28.87 ft (normal load)
   220.00 m / 220.00 m x 32.00 m (Bulges 36.00 m)  x 8.80 m

Armament:
      8 - 15.00" / 381 mm guns (4x2 guns), 2,000.00lbs / 907.18kg shells, 1920 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread, 2 raised mounts - superfiring
      16 - 4.75" / 121 mm guns (8x2 guns), 50.00lbs / 22.68kg shells, 1920 Model
     Breech loading guns in deck mounts with hoists
     on side, all amidships
      4 - 1.58" / 40.0 mm guns in single mounts, 2.00lbs / 0.91kg shells, 1920 Model
     Breech loading guns in deck mounts
     on centreline ends, evenly spread, all raised mounts - superfiring
   Weight of broadside 16,808 lbs / 7,624 kg
   Shells per gun, main battery: 120

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   13.0" / 330 mm   470.00 ft / 143.26 m   17.56 ft / 5.35 m
   Ends:   2.00" / 51 mm   251.78 ft / 76.74 m   17.56 ft / 5.35 m
     Main Belt covers 100 % of normal length

   - Torpedo Bulkhead and Bulges:
      2.00" / 51 mm   721.78 ft / 220.00 m   32.15 ft / 9.80 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   16.0" / 406 mm   8.00" / 203 mm      13.0" / 330 mm
   2nd:   3.00" / 76 mm   2.00" / 51 mm      2.00" / 51 mm

   - Armour deck: 3.00" / 76 mm, Conning tower: 16.00" / 406 mm

Machinery:
   Oil fired boilers, steam turbines,
   Electric motors, 4 shafts, 110,000 shp / 82,060 Kw = 27.50 kts
   Range 12,000nm at 12.00 kts
   Bunker at max displacement = 4,442 tons

Complement:
   1,397 - 1,817

Cost:
   £7.733 million / $30.933 million

Distribution of weights at normal displacement:
   Armament: 1,796 tons, 4.6 %
   Armour: 13,303 tons, 33.8 %
      - Belts: 4,972 tons, 12.6 %
      - Torpedo bulkhead: 1,717 tons, 4.4 %
      - Armament: 3,252 tons, 8.3 %
      - Armour Deck: 2,963 tons, 7.5 %
      - Conning Tower: 399 tons, 1.0 %
   Machinery: 3,846 tons, 9.8 %
   Hull, fittings & equipment: 15,655 tons, 39.7 %
   Fuel, ammunition & stores: 4,388 tons, 11.1 %
   Miscellaneous weights: 400 tons, 1.0 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     54,831 lbs / 24,871 Kg = 32.5 x 15.0 " / 381 mm shells or 10.9 torpedoes
   Stability (Unstable if below 1.00): 1.09
   Metacentric height 6.4 ft / 1.9 m
   Roll period: 19.6 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0.49
   Seaboat quality  (Average = 1.00): 1.10

Hull form characteristics:
   Hull has raised forecastle
   Block coefficient: 0.560
   Length to Beam Ratio: 6.11 : 1
   'Natural speed' for length: 26.87 kts
   Power going to wave formation at top speed: 51 %
   Trim (Max stability = 0, Max steadiness = 100): 64
   Bow angle (Positive = bow angles forward): 0.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      31.17 ft / 9.50 m
      - Forecastle (20 %):   24.61 ft / 7.50 m (21.33 ft / 6.50 m aft of break)
      - Mid (50 %):      21.33 ft / 6.50 m
      - Quarterdeck (15 %):   21.33 ft / 6.50 m
      - Stern:      21.33 ft / 6.50 m
      - Average freeboard:   22.51 ft / 6.86 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 84.6 %
      - Above water (accommodation/working, high = better): 155.2 %
   Waterplane Area: 53,388 Square feet or 4,960 Square metres
   Displacement factor (Displacement / loading): 110 %
   Structure weight / hull surface area: 207 lbs/sq ft or 1,013 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.97
      - Longitudinal: 1.31
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is excellent
   Ship has slow, easy roll, a good, steady gun platform

Main belt armor sloped 20 degrees, giving a vertical height of 16.5 feet. Relative thickness to a 90 degree impact is 13.83 inches.

End belt armor sloped to 20 degrees, giving a vertical height of 16.5 feet. Relative thickness to a 90 degree impact is 2.13 inches.

Misc Weight (400 tons):
250 tons fire control system
25 tons radar
25 tons long range wireless
25 tons night fighting gear
25 tons crane and catapult for floatplane
10 tons 2x floatplanes
40 tons reserve

[Sachmle]

A TDS would never run the whole length of a ship. The ends are too narrow. I'm not sure if their is a hard fast rule, but I'd presume that the main belt length is long enough.

[Delta Force]

Corrected the TDS and added the weight saved to the armor belts.

15 Inch Battleshipv4, CSA Battleship laid down 1920

Displacement:
   35,000 t light; 36,920 t standard; 39,388 t normal; 41,362 t full load

Dimensions: Length overall / water x beam x draught
   721.78 ft / 721.78 ft x 104.99 ft (Bulges 118.11 ft) x 28.87 ft (normal load)
   220.00 m / 220.00 m x 32.00 m (Bulges 36.00 m)  x 8.80 m

Armament:
      8 - 15.00" / 381 mm guns (4x2 guns), 2,000.00lbs / 907.18kg shells, 1920 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread, 2 raised mounts - superfiring
      16 - 4.75" / 121 mm guns (8x2 guns), 50.00lbs / 22.68kg shells, 1920 Model
     Breech loading guns in deck mounts with hoists
     on side, all amidships
      4 - 1.58" / 40.0 mm guns in single mounts, 2.00lbs / 0.91kg shells, 1920 Model
     Breech loading guns in deck mounts
     on centreline ends, evenly spread, all raised mounts - superfiring
   Weight of broadside 16,808 lbs / 7,624 kg
   Shells per gun, main battery: 120

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   13.8" / 351 mm   470.00 ft / 143.26 m   17.56 ft / 5.35 m
   Ends:   4.00" / 102 mm   251.78 ft / 76.74 m   17.56 ft / 5.35 m
     Main Belt covers 100 % of normal length

   - Torpedo Bulkhead and Bulges:
      2.00" / 51 mm   470.00 ft / 143.26 m   32.15 ft / 9.80 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   16.0" / 406 mm   8.00" / 203 mm      13.0" / 330 mm
   2nd:   3.00" / 76 mm   2.00" / 51 mm      2.00" / 51 mm

   - Armour deck: 3.00" / 76 mm, Conning tower: 16.00" / 406 mm

Machinery:
   Oil fired boilers, steam turbines,
   Electric motors, 4 shafts, 110,000 shp / 82,060 Kw = 27.50 kts
   Range 12,000nm at 12.00 kts
   Bunker at max displacement = 4,442 tons

Complement:
   1,397 - 1,817

Cost:
   £7.733 million / $30.933 million

Distribution of weights at normal displacement:
   Armament: 1,796 tons, 4.6 %
   Armour: 13,317 tons, 33.8 %
      - Belts: 5,585 tons, 14.2 %
      - Torpedo bulkhead: 1,118 tons, 2.8 %
      - Armament: 3,252 tons, 8.3 %
      - Armour Deck: 2,963 tons, 7.5 %
      - Conning Tower: 399 tons, 1.0 %
   Machinery: 3,846 tons, 9.8 %
   Hull, fittings & equipment: 15,641 tons, 39.7 %
   Fuel, ammunition & stores: 4,388 tons, 11.1 %
   Miscellaneous weights: 400 tons, 1.0 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     54,332 lbs / 24,644 Kg = 32.2 x 15.0 " / 381 mm shells or 10.1 torpedoes
   Stability (Unstable if below 1.00): 1.08
   Metacentric height 6.2 ft / 1.9 m
   Roll period: 19.9 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.49
   Seaboat quality  (Average = 1.00): 1.08

Hull form characteristics:
   Hull has raised forecastle
   Block coefficient: 0.560
   Length to Beam Ratio: 6.11 : 1
   'Natural speed' for length: 26.87 kts
   Power going to wave formation at top speed: 51 %
   Trim (Max stability = 0, Max steadiness = 100): 65
   Bow angle (Positive = bow angles forward): 0.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      31.17 ft / 9.50 m
      - Forecastle (20 %):   24.61 ft / 7.50 m (21.33 ft / 6.50 m aft of break)
      - Mid (50 %):      21.33 ft / 6.50 m
      - Quarterdeck (15 %):   21.33 ft / 6.50 m
      - Stern:      21.33 ft / 6.50 m
      - Average freeboard:   22.51 ft / 6.86 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 84.6 %
      - Above water (accommodation/working, high = better): 155.2 %
   Waterplane Area: 53,388 Square feet or 4,960 Square metres
   Displacement factor (Displacement / loading): 110 %
   Structure weight / hull surface area: 207 lbs/sq ft or 1,012 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.97
      - Longitudinal: 1.29
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is excellent
   Ship has slow, easy roll, a good, steady gun platform

Main belt armor sloped 20 degrees, giving a vertical height of 16.5 feet. Relative thickness to a 90 degree impact is 14.69 inches.

End belt armor sloped to 20 degrees, giving a vertical height of 16.5 feet. Relative thickness to a 90 degree impact is 4.26 inches.

Misc Weight (400 tons):
250 tons fire control system
25 tons radar
25 tons long range wireless
25 tons night fighting gear
25 tons crane and catapult for floatplane
10 tons 2x floatplanes
40 tons reserve

[Valles]

Now that there is a nice fast battleship.

[Jefgte]

Nice BB, well balanced in - armament - speed - armour.


Jef

[mentat]

it is looking nice  :)

   - only picky things i can see:

     Stability - bit low at 1.08

      Deck armour - 3" prob. OK right now - but by time built + in service - looking vulnerable to 14" shell fire and above at longer ranges

  can't easily see what to try trading-off with though - drop to 27 knots ?

[Delta Force]

I could also relax trim, isn't 50% steadiness an "average" accuracy?

[Sachmle]

I could also relax trim, isn't 50% steadiness an "average" accuracy?

Yes. You could back it down to 65% (I have a thing for even numbering i.e 50,55,60,65,70)

[Delta Force]

Here is a lighter counterpart to the battleship above. It has the same armament and armor, the only difference being that this is 5.5 knots slower and is 9,000 tons lighter. It's major role would be operations close to the CSA itself, due to its lower speed and range.

15 Inch Light Battleship, CSA Light Battleship laid down 1920

Displacement:
   26,000 t light; 27,714 t standard; 29,089 t normal; 30,189 t full load

Dimensions: Length overall / water x beam x draught
   557.74 ft / 557.74 ft x 104.99 ft x 28.87 ft (normal load)
   170.00 m / 170.00 m x 32.00 m  x 8.80 m

Armament:
      8 - 15.00" / 381 mm guns (4x2 guns), 2,000.00lbs / 907.18kg shells, 1920 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread, 2 raised mounts - superfiring
      16 - 4.75" / 121 mm guns (8x2 guns), 50.00lbs / 22.68kg shells, 1920 Model
     Quick firing guns in deck mounts with hoists
     on side, all amidships
      4 - 1.58" / 40.0 mm guns in single mounts, 2.00lbs / 0.91kg shells, 1920 Model
     Anti-aircraft guns in deck mounts
     on centreline ends, evenly spread, all raised mounts - superfiring
   Weight of broadside 16,808 lbs / 7,624 kg
   Shells per gun, main battery: 120

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   13.8" / 351 mm   370.00 ft / 112.78 m   17.56 ft / 5.35 m
   Ends:   4.00" / 102 mm   187.74 ft / 57.22 m   17.56 ft / 5.35 m
     Main Belt covers 102 % of normal length

   - Torpedo Bulkhead:
      2.00" / 51 mm   370.00 ft / 112.78 m   32.15 ft / 9.80 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   16.0" / 406 mm   8.00" / 203 mm      13.0" / 330 mm
   2nd:   3.00" / 76 mm   2.00" / 51 mm      2.00" / 51 mm

   - Armour deck: 3.00" / 76 mm, Conning tower: 16.00" / 406 mm

Machinery:
   Oil fired boilers, steam turbines,
   Electric motors, 4 shafts, 42,800 shp / 31,929 Kw = 22.01 kts
   Range 8,000nm at 12.00 kts
   Bunker at max displacement = 2,475 tons

Complement:
   1,113 - 1,447

Cost:
   £6.211 million / $24.845 million

Distribution of weights at normal displacement:
   Armament: 1,796 tons, 6.2 %
   Armour: 10,919 tons, 37.5 %
      - Belts: 4,475 tons, 15.4 %
      - Torpedo bulkhead: 880 tons, 3.0 %
      - Armament: 2,856 tons, 9.8 %
      - Armour Deck: 2,382 tons, 8.2 %
      - Conning Tower: 326 tons, 1.1 %
   Machinery: 1,496 tons, 5.1 %
   Hull, fittings & equipment: 11,389 tons, 39.2 %
   Fuel, ammunition & stores: 3,089 tons, 10.6 %
   Miscellaneous weights: 400 tons, 1.4 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     40,335 lbs / 18,296 Kg = 23.9 x 15.0 " / 381 mm shells or 7.7 torpedoes
   Stability (Unstable if below 1.00): 1.14
   Metacentric height 6.9 ft / 2.1 m
   Roll period: 16.8 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.51
   Seaboat quality  (Average = 1.00): 1.15

Hull form characteristics:
   Hull has raised forecastle
   Block coefficient: 0.602
   Length to Beam Ratio: 5.31 : 1
   'Natural speed' for length: 23.62 kts
   Power going to wave formation at top speed: 50 %
   Trim (Max stability = 0, Max steadiness = 100): 43
   Bow angle (Positive = bow angles forward): 0.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      27.07 ft / 8.25 m
      - Forecastle (20 %):   20.51 ft / 6.25 m (17.22 ft / 5.25 m aft of break)
      - Mid (50 %):      17.22 ft / 5.25 m
      - Quarterdeck (15 %):   17.22 ft / 5.25 m
      - Stern:      17.22 ft / 5.25 m
      - Average freeboard:   18.41 ft / 5.61 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 81.8 %
      - Above water (accommodation/working, high = better): 126.5 %
   Waterplane Area: 42,916 Square feet or 3,987 Square metres
   Displacement factor (Displacement / loading): 101 %
   Structure weight / hull surface area: 202 lbs/sq ft or 988 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.94
      - Longitudinal: 1.72
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is excellent
   Room for accommodation and workspaces is excellent

Main belt armor sloped 20 degrees, giving a vertical height of 16.5 feet. Relative thickness to a 90 degree impact is 14.69 inches.

End belt armor sloped to 20 degrees, giving a vertical height of 16.5 feet. Relative thickness to a 90 degree impact is 4.26 inches.

Misc Weight (400 tons):
250 tons fire control system
25 tons radar
25 tons long range wireless
25 tons night fighting gear
25 tons crane and catapult for floatplane
10 tons 2x floatplanes
40 tons reserve

[Delta Force]

Here is a design for the treaty battleships. I converted the main guns into 16.5 Skodas and increased the speed by another knot relative to the 35,000 ton fast battleship. However, if the speed is maintained another half inch can be added to the deck armor.

16.5 Inch Treaty Battleship, CSA Treaty Battleship laid down 1920

Displacement:
   40,400 t light; 42,708 t standard; 45,468 t normal; 47,677 t full load

Dimensions: Length overall / water x beam x draught
   820.21 ft / 820.21 ft x 104.99 ft (Bulges 118.11 ft) x 28.87 ft (normal load)
   250.00 m / 250.00 m x 32.00 m (Bulges 36.00 m)  x 8.80 m

Armament:
      8 - 16.50" / 419 mm guns (4x2 guns), 2,500.00lbs / 1,133.98kg shells, 1920 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread, 2 raised mounts - superfiring
      16 - 4.75" / 121 mm guns (8x2 guns), 50.00lbs / 22.68kg shells, 1920 Model
     Breech loading guns in deck mounts with hoists
     on side, all amidships
      4 - 1.58" / 40.0 mm guns in single mounts, 2.00lbs / 0.91kg shells, 1920 Model
     Breech loading guns in deck mounts
     on centreline ends, evenly spread, all raised mounts - superfiring
   Weight of broadside 20,808 lbs / 9,438 kg
   Shells per gun, main battery: 120

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   13.8" / 351 mm   470.00 ft / 143.26 m   17.56 ft / 5.35 m
   Ends:   4.00" / 102 mm   251.78 ft / 76.74 m   17.56 ft / 5.35 m
     98.43 ft / 30.00 m Unarmoured ends
     Main Belt covers 88 % of normal length
     Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead and Bulges:
      2.00" / 51 mm   470.00 ft / 143.26 m   32.15 ft / 9.80 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   16.0" / 406 mm   8.00" / 203 mm      13.0" / 330 mm
   2nd:   3.00" / 76 mm   2.00" / 51 mm      2.00" / 51 mm

   - Armour deck: 3.00" / 76 mm, Conning tower: 16.00" / 406 mm

Machinery:
   Oil fired boilers, steam turbines,
   Electric motors, 4 shafts, 131,795 shp / 98,319 Kw = 28.54 kts
   Range 12,000nm at 12.00 kts
   Bunker at max displacement = 4,968 tons

Complement:
   1,556 - 2,023

Cost:
   £9.541 million / $38.165 million

Distribution of weights at normal displacement:
   Armament: 2,354 tons, 5.2 %
   Armour: 14,230 tons, 31.3 %
      - Belts: 5,646 tons, 12.4 %
      - Torpedo bulkhead: 1,118 tons, 2.5 %
      - Armament: 3,631 tons, 8.0 %
      - Armour Deck: 3,395 tons, 7.5 %
      - Conning Tower: 439 tons, 1.0 %
   Machinery: 4,608 tons, 10.1 %
   Hull, fittings & equipment: 18,808 tons, 41.4 %
   Fuel, ammunition & stores: 5,068 tons, 11.1 %
   Miscellaneous weights: 400 tons, 0.9 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     57,922 lbs / 26,273 Kg = 25.8 x 16.5 " / 419 mm shells or 9.6 torpedoes
   Stability (Unstable if below 1.00): 1.08
   Metacentric height 6.3 ft / 1.9 m
   Roll period: 19.8 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.58
   Seaboat quality  (Average = 1.00): 1.09

Hull form characteristics:
   Hull has raised forecastle
   Block coefficient: 0.569
   Length to Beam Ratio: 6.94 : 1
   'Natural speed' for length: 28.64 kts
   Power going to wave formation at top speed: 48 %
   Trim (Max stability = 0, Max steadiness = 100): 64
   Bow angle (Positive = bow angles forward): 0.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      31.17 ft / 9.50 m
      - Forecastle (20 %):   24.61 ft / 7.50 m (21.33 ft / 6.50 m aft of break)
      - Mid (50 %):      21.33 ft / 6.50 m
      - Quarterdeck (15 %):   21.33 ft / 6.50 m
      - Stern:      21.33 ft / 6.50 m
      - Average freeboard:   22.51 ft / 6.86 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 91.3 %
      - Above water (accommodation/working, high = better): 159.7 %
   Waterplane Area: 61,176 Square feet or 5,683 Square metres
   Displacement factor (Displacement / loading): 107 %
   Structure weight / hull surface area: 218 lbs/sq ft or 1,063 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.99
      - Longitudinal: 1.02
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is excellent
   Ship has slow, easy roll, a good, steady gun platform

Main belt armor sloped 20 degrees, giving a vertical height of 16.5 feet. Relative thickness to a 90 degree impact is 14.69 inches.

End belt armor sloped to 20 degrees, giving a vertical height of 16.5 feet. Relative thickness to a 90 degree impact is 4.26 inches.

Misc Weight (400 tons):
250 tons fire control system
25 tons radar
25 tons long range wireless
25 tons night fighting gear
25 tons crane and catapult for floatplane
10 tons 2x floatplanes
40 tons reserve

[Sachmle]

Deck armor. 3" is 1910-1918 era good, fire is getting longer here, and guns are getting bigger. I shoot for 4" total, 1" weatherdeck, 3" main deck.

[Kaiser Kirk]

Main Belt covers 88 % of normal length
     Main belt does not fully cover magazines and engineering spaces

This is typically not desirable.
Plus you should have some anti-balloon guns still.
Relatively low BC., and that's outside the bulges. BC inside the bulges is less.
Stability lower than the customary 1.10

In this time frame effective FC is being extended out to 24k yards- you won't always be able to see that far, but when you can...
Your 3" deck armor is only proof against 16" out to ~19,000 yards. Maybe 18,000.

[Delta Force]

Main Belt covers 88 % of normal length
     Main belt does not fully cover magazines and engineering spaces

This is typically not desirable.
Plus you should have some anti-balloon guns still.
Relatively low BC., and that's outside the bulges. BC inside the bulges is less.
Stability lower than the customary 1.10

In this time frame effective FC is being extended out to 24k yards- you won't always be able to see that far, but when you can...
Your 3" deck armor is only proof against 16" out to ~19,000 yards. Maybe 18,000.

How about this?

16.5 Inch Treaty Battleshipv2, CSA Treaty Battleship laid down 1920

Displacement:
   40,400 t light; 42,708 t standard; 45,468 t normal; 47,677 t full load

Dimensions: Length overall / water x beam x draught
   820.21 ft / 820.21 ft x 104.99 ft (Bulges 118.11 ft) x 28.87 ft (normal load)
   250.00 m / 250.00 m x 32.00 m (Bulges 36.00 m)  x 8.80 m

Armament:
      8 - 16.50" / 419 mm guns (4x2 guns), 2,500.00lbs / 1,133.98kg shells, 1920 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread, 2 raised mounts - superfiring
      16 - 4.75" / 121 mm guns (8x2 guns), 50.00lbs / 22.68kg shells, 1920 Model
     Breech loading guns in deck mounts with hoists
     on side, all amidships
      4 - 1.58" / 40.0 mm guns in single mounts, 2.00lbs / 0.91kg shells, 1920 Model
     Breech loading guns in deck mounts
     on centreline ends, evenly spread, all raised mounts - superfiring
   Weight of broadside 20,808 lbs / 9,438 kg
   Shells per gun, main battery: 120

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   13.8" / 351 mm   470.00 ft / 143.26 m   17.56 ft / 5.35 m
   Ends:   4.00" / 102 mm   251.78 ft / 76.74 m   17.56 ft / 5.35 m
     98.43 ft / 30.00 m Unarmoured ends
     Main Belt covers 88 % of normal length

   - Torpedo Bulkhead and Bulges:
      2.00" / 51 mm   470.00 ft / 143.26 m   32.15 ft / 9.80 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   16.0" / 406 mm   8.00" / 203 mm      13.0" / 330 mm
   2nd:   3.00" / 76 mm   2.00" / 51 mm      2.00" / 51 mm

   - Armour deck: 3.50" / 89 mm, Conning tower: 16.00" / 406 mm

Machinery:
   Oil fired boilers, steam turbines,
   Electric motors, 4 shafts, 114,170 shp / 85,171 Kw = 27.50 kts
   Range 12,000nm at 12.00 kts
   Bunker at max displacement = 4,968 tons

Complement:
   1,556 - 2,023

Cost:
   £9.337 million / $37.349 million

Distribution of weights at normal displacement:
   Armament: 2,354 tons, 5.2 %
   Armour: 14,795 tons, 32.5 %
      - Belts: 5,646 tons, 12.4 %
      - Torpedo bulkhead: 1,118 tons, 2.5 %
      - Armament: 3,631 tons, 8.0 %
      - Armour Deck: 3,961 tons, 8.7 %
      - Conning Tower: 439 tons, 1.0 %
   Machinery: 3,992 tons, 8.8 %
   Hull, fittings & equipment: 18,858 tons, 41.5 %
   Fuel, ammunition & stores: 5,068 tons, 11.1 %
   Miscellaneous weights: 400 tons, 0.9 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     61,684 lbs / 27,979 Kg = 27.5 x 16.5 " / 419 mm shells or 10.6 torpedoes
   Stability (Unstable if below 1.00): 1.08
   Metacentric height 6.2 ft / 1.9 m
   Roll period: 19.9 seconds
   Steadiness   - As gun platform (Average = 50 %): 76 %
         - Recoil effect (Restricted arc if above 1.00): 0.61
   Seaboat quality  (Average = 1.00): 1.18

Hull form characteristics:
   Hull has raised forecastle
   Block coefficient: 0.569
   Length to Beam Ratio: 6.94 : 1
   'Natural speed' for length: 28.64 kts
   Power going to wave formation at top speed: 46 %
   Trim (Max stability = 0, Max steadiness = 100): 64
   Bow angle (Positive = bow angles forward): 0.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      31.17 ft / 9.50 m
      - Forecastle (20 %):   24.61 ft / 7.50 m (21.33 ft / 6.50 m aft of break)
      - Mid (50 %):      21.33 ft / 6.50 m
      - Quarterdeck (15 %):   21.33 ft / 6.50 m
      - Stern:      21.33 ft / 6.50 m
      - Average freeboard:   22.51 ft / 6.86 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 86.0 %
      - Above water (accommodation/working, high = better): 159.7 %
   Waterplane Area: 61,176 Square feet or 5,683 Square metres
   Displacement factor (Displacement / loading): 108 %
   Structure weight / hull surface area: 218 lbs/sq ft or 1,066 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 1.00
      - Longitudinal: 1.04
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is excellent
   Ship has slow, easy roll, a good, steady gun platform

Main belt armor sloped 20 degrees, giving a vertical height of 16.5 feet. Relative thickness to a 90 degree impact is 14.69 inches.

End belt armor sloped to 20 degrees, giving a vertical height of 16.5 feet. Relative thickness to a 90 degree impact is 4.26 inches.

Misc Weight (400 tons):
250 tons fire control system
25 tons radar
25 tons long range wireless
25 tons night fighting gear
25 tons crane and catapult for floatplane
10 tons 2x floatplanes
40 tons reserve

[mentat]

it's good and powerful - but I think Deck protection should have greater priority over the End Belts - maybe something like Deck 4.5" over Mags, 4" over Machinery - sim as avge 4.25"

  + EB reduced to compensate (less height?/thin under waterline) and maybe can lose the 0.5 knot - i think doesn't register in Battle sim anyway ...

also Stability vs. Steadiness can be trimmed - Steadiness at 76% is beyond reqmt whilst Stability at 1.08 is a bit under ...

   - getting close  :D