The GB/CL/1937 converted to an 8in-gun cruiser: GB/CA/1937

I thought that converting the GB/CL/1937 to have 8-in guns would be interesting, sort of along the lines of the Mogami class. The speed is reduced to 35 knots, which is sufficient, anyway. The new armament is 8-8in BLR, 12-4in AA, 32-2pdr AA, and 16-21in TT. The armour basis is still 4in with a 2in deck. I did decide that a heavy cruiser needed a torpedo bulkhead, and that was a factor in reducing the speed. This is the revised Springsharp report:

GB/CA/1937, Great Britain Heavy Cruiser laid down 1937

Displacement:
 13,882 t light; 14,342 t standard; 15,700 t normal; 16,786 t full load

Dimensions: Length overall / water x beam x draught
 668.96 ft / 665.00 ft x 64.00 ft x 25.00 ft (normal load)
 203.90 m / 202.69 m x 19.51 m  x 7.62 m

Armament:
      8 - 8.00" / 203 mm guns (4x2 guns), 256.00lbs / 116.12kg shells, 1937 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 2 raised mounts - superfiring
      12 - 4.00" / 102 mm guns (6x2 guns), 32.00lbs / 14.51kg shells, 1937 Model
   Anti-aircraft guns in deck mounts with hoists
   on side, all amidships, all raised mounts - superfiring
      32 - 1.57" / 40.0 mm guns (8x4 guns), 2.00lbs / 0.91kg shells, 1937 Model
   Breech loading guns in deck mounts 
   on side, evenly spread, 4 raised mounts
 Weight of broadside 2,496 lbs / 1,132 kg
 Shells per gun, main battery: 100
 16 - 21.0" / 533.4 mm above water torpedoes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 4.00" / 102 mm 560.00 ft / 170.69 m 12.00 ft / 3.66 m
 Ends: Unarmoured
   Main Belt covers 130 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.00" / 25 mm 560.00 ft / 170.69 m 24.00 ft / 7.32 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 4.00" / 102 mm 3.00" / 76 mm  4.00" / 102 mm
 2nd: 1.00" / 25 mm 1.00" / 25 mm  1.00" / 25 mm

   - Armour deck: 2.00" / 51 mm, Conning tower: 4.00" / 102 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 153,169 shp / 114,264 Kw = 35.00 kts
 Range 8,500nm at 15.00 kts
 Bunker at max displacement = 2,444 tons

Complement:
 700 - 911

Cost:
 £7.321 million / $29.283 million

Distribution of weights at normal displacement:
 Armament: 312 tons, 2.0 %
 Armour: 3,220 tons, 20.5 %
    - Belts: 1,075 tons, 6.8 %
    - Torpedo bulkhead: 497 tons, 3.2 %
    - Armament: 529 tons, 3.4 %
    - Armour Deck: 1,065 tons, 6.8 %
    - Conning Tower: 54 tons, 0.3 %
 Machinery: 4,245 tons, 27.0 %
 Hull, fittings & equipment: 6,105 tons, 38.9 %
 Fuel, ammunition & stores: 1,818 tons, 11.6 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   17,756 lbs / 8,054 Kg = 69.4 x 8.0 " / 203 mm shells or 2.2 torpedoes
 Stability (Unstable if below 1.00): 1.13
 Metacentric height 3.2 ft / 1.0 m
 Roll period: 15.0 seconds
 Steadiness - As gun platform (Average = 50 %): 59 %
   - Recoil effect (Restricted arc if above 1.00): 0.63
 Seaboat quality  (Average = 1.00): 1.18

Hull form characteristics:
 Hull has a flush deck
 Block coefficient: 0.516
 Length to Beam Ratio: 10.39 : 1
 'Natural speed' for length: 25.79 kts
 Power going to wave formation at top speed: 58 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 4.00 degrees
 Stern overhang: 2.00 ft / 0.61 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  28.00 ft / 8.53 m
    - Forecastle (20 %): 24.00 ft / 7.32 m
    - Mid (50 %):  24.00 ft / 7.32 m
    - Quarterdeck (15 %): 24.00 ft / 7.32 m
    - Stern:  24.00 ft / 7.32 m
    - Average freeboard: 24.32 ft / 7.41 m
 Ship tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 149.7 %
  - Above water (accommodation/working, high = better): 139.3 %
 Waterplane Area: 28,788 Square feet or 2,674 Square metres
 Displacement factor (Displacement / loading): 111 %
 Structure weight / hull surface area: 118 lbs/sq ft or 576 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.94
  - Longitudinal: 1.71
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent