The J/CB/1927 design

The J/CB/1927 design is better protected than the previous version. The armour basis is now 14 inches. Otherwise, the design is very similar to the corresponding battleship. The speed is 33 knots, still, and the range is 12,000nm at 15 knots. The seakeeping is not quite as good as the preceding design, but is adequate. This is the Springsharp report:

J/CB/1927, Japan Battlecruiser laid down 1927

Displacement:
 75,199 t light; 78,484 t standard; 84,500 t normal; 89,313 t full load

Dimensions: Length overall / water x beam x draught
 970.68 ft / 965.00 ft x 122.00 ft x 35.00 ft (normal load)
 295.86 m / 294.13 m x 37.19 m  x 10.67 m

Armament:
      10 - 18.00" / 457 mm guns (4 mounts), 2,916.00lbs / 1,322.68kg shells, 1927 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 2 raised mounts - superfiring
      12 - 6.00" / 152 mm guns (4x3 guns), 108.00lbs / 48.99kg shells, 1927 Model
   Quick firing guns in turrets (on barbettes)
   on side, all amidships
      12 - 5.00" / 127 mm guns (6x2 guns), 62.50lbs / 28.35kg shells, 1927 Model
   Dual purpose guns in deck mounts with hoists
   on side, evenly spread, all raised mounts
      42 - 2.24" / 57.0 mm guns (21x2 guns), 5.65lbs / 2.56kg shells, 1927 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread, 18 raised mounts
 Weight of broadside 31,443 lbs / 14,262 kg
 Shells per gun, main battery: 90

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 14.0" / 356 mm 640.00 ft / 195.07 m 9.00 ft / 2.74 m
 Ends: Unarmoured
 Upper: 12.0" / 305 mm 640.00 ft / 195.07 m 8.00 ft / 2.44 m
   Main Belt covers 102 % of normal length

   - Torpedo Bulkhead:
  5.00" / 127 mm 640.00 ft / 195.07 m 32.00 ft / 9.75 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 14.0" / 356 mm 12.0" / 305 mm  14.0" / 356 mm
 2nd: 6.00" / 152 mm 6.00" / 152 mm  6.00" / 152 mm

   - Armour deck: 7.00" / 178 mm, Conning tower: 16.00" / 406 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 6 shafts, 334,570 shp / 249,589 Kw = 33.00 kts
 Range 12,000nm at 15.00 kts
 Bunker at max displacement = 10,828 tons

Complement:
 2,477 - 3,221

Cost:
 £26.953 million / $107.811 million

Distribution of weights at normal displacement:
 Armament: 3,930 tons, 4.7 %
 Armour: 30,083 tons, 35.6 %
    - Belts: 6,084 tons, 7.2 %
    - Torpedo bulkhead: 3,789 tons, 4.5 %
    - Armament: 7,132 tons, 8.4 %
    - Armour Deck: 12,414 tons, 14.7 %
    - Conning Tower: 664 tons, 0.8 %
 Machinery: 10,561 tons, 12.5 %
 Hull, fittings & equipment: 30,624 tons, 36.2 %
 Fuel, ammunition & stores: 9,301 tons, 11.0 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   113,026 lbs / 51,268 Kg = 38.8 x 18.0 " / 457 mm shells or 18.0 torpedoes
 Stability (Unstable if below 1.00): 1.13
 Metacentric height 8.4 ft / 2.6 m
 Roll period: 17.6 seconds
 Steadiness - As gun platform (Average = 50 %): 51 %
   - Recoil effect (Restricted arc if above 1.00): 0.69
 Seaboat quality  (Average = 1.00): 1.03

Hull form characteristics:
 Hull has a flush deck
 Block coefficient: 0.718
 Length to Beam Ratio: 7.91 : 1
 'Natural speed' for length: 31.06 kts
 Power going to wave formation at top speed: 54 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 6.00 degrees
 Stern overhang: 2.00 ft / 0.61 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): 90.5 %
  - Above water (accommodation/working, high = better): 206.4 %
 Waterplane Area: 95,861 Square feet or 8,906 Square metres
 Displacement factor (Displacement / loading): 102 %
 Structure weight / hull surface area: 234 lbs/sq ft or 1,143 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