The J/BB/1937 design

The J/BB/1937 design is rather like some of the "what if" designs that I have seen, such as at Alt Naval. This design escalates things further by going with 12-18in guns in triple turrets. The armour basis is expanded to 18in with an 8in torpedo bulkhead. This is a supership, in that it has such positives characteristics. Springsharp seems to have nothing bad to say about this design. This is the report:

J/BB/1937, Japan Battleship laid down 1937

Displacement:
 82,462 t light; 86,245 t standard; 92,100 t normal; 96,784 t full load

Dimensions: Length overall / water x beam x draught
 922.30 ft / 915.00 ft x 128.00 ft x 35.00 ft (normal load)
 281.12 m / 278.89 m x 39.01 m  x 10.67 m

Armament:
      12 - 18.00" / 457 mm guns (4 mounts), 2,916.00lbs / 1,322.68kg shells, 1937 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 4 raised guns - superfiring
      12 - 6.00" / 152 mm guns (4x3 guns), 108.00lbs / 48.99kg shells, 1937 Model
   Quick firing guns in turrets (on barbettes)
   on side, all amidships
      24 - 5.00" / 127 mm guns (12x2 guns), 62.50lbs / 28.35kg shells, 1937 Model
   Dual purpose guns in deck mounts with hoists
   on side, evenly spread, 6 raised mounts
      64 - 2.24" / 57.0 mm guns (32x2 guns), 5.65lbs / 2.56kg shells, 1937 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread, 18 raised mounts
 Weight of broadside 38,150 lbs / 17,304 kg
 Shells per gun, main battery: 90

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 18.0" / 457 mm 650.00 ft / 198.12 m 9.00 ft / 2.74 m
 Ends: Unarmoured
 Upper: 12.0" / 305 mm 650.00 ft / 198.12 m 8.00 ft / 2.44 m
   Main Belt covers 109 % of normal length

   - Torpedo Bulkhead:
  8.00" / 203 mm 650.00 ft / 198.12 m 34.00 ft / 10.36 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 18.0" / 457 mm 13.0" / 330 mm  18.0" / 457 mm
 2nd: 6.00" / 152 mm 6.00" / 152 mm  6.00" / 152 mm

   - Armour deck: 8.00" / 203 mm, Conning tower: 18.00" / 457 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 256,964 shp / 191,695 Kw = 30.00 kts
 Range 12,000nm at 15.00 kts
 Bunker at max displacement = 10,538 tons

Complement:
 2,642 - 3,436

Cost:
 £43.031 million / $172.123 million

Distribution of weights at normal displacement:
 Armament: 4,769 tons, 5.2 %
 Armour: 38,083 tons, 41.3 %
    - Belts: 7,181 tons, 7.8 %
    - Torpedo bulkhead: 6,542 tons, 7.1 %
    - Armament: 8,594 tons, 9.3 %
    - Armour Deck: 14,976 tons, 16.3 %
    - Conning Tower: 791 tons, 0.9 %
 Machinery: 7,122 tons, 7.7 %
 Hull, fittings & equipment: 32,489 tons, 35.3 %
 Fuel, ammunition & stores: 9,638 tons, 10.5 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   143,042 lbs / 64,883 Kg = 49.1 x 18.0 " / 457 mm shells or 30.4 torpedoes
 Stability (Unstable if below 1.00): 1.13
 Metacentric height 9.1 ft / 2.8 m
 Roll period: 17.8 seconds
 Steadiness - As gun platform (Average = 50 %): 56 %
   - Recoil effect (Restricted arc if above 1.00): 0.71
 Seaboat quality  (Average = 1.00): 1.12

Hull form characteristics:
 Hull has a flush deck
 Block coefficient: 0.786
 Length to Beam Ratio: 7.15 : 1
 'Natural speed' for length: 30.25 kts
 Power going to wave formation at top speed: 53 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 7.00 degrees
 Stern overhang: 3.00 ft / 0.91 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  35.00 ft / 10.67 m
    - Forecastle (20 %): 28.00 ft / 8.53 m
    - Mid (67 %):  28.00 ft / 8.53 m
    - Quarterdeck (15 %): 28.00 ft / 8.53 m
    - Stern:  28.00 ft / 8.53 m
    - Average freeboard: 28.56 ft / 8.71 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 76.2 %
  - Above water (accommodation/working, high = better): 204.3 %
 Waterplane Area: 101,187 Square feet or 9,401 Square metres
 Displacement factor (Displacement / loading): 102 %
 Structure weight / hull surface area: 243 lbs/sq ft or 1,184 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.99
  - Longitudinal: 1.15
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is excellent
 Room for accommodation and workspaces is excellent