The big and fast GB/CA/1921 "Fast"

This version of the GB/CA/1921 is trying to be compatible with my very fast light cruiser for the same date. This design is more complete and has an AA and light AA armament as well as a main armament. The ship is designed for a 37 knot speed. To achieve that with 9-9.2in/55 guns and acceptable hull strength and sea keeping takes a large ship in Springsharp 3.0b2 Beta. The displacement is 18,099 tons standard. To be that small requires substantial length, to improve sea keeping and to reduce the required power. This is the Springsharp report:

GB/CA/1921 Fast, Great Britain Heavy Cruiser laid down 1921 (Engine 1941)

Displacement:
 17,431 t light; 18,099 t standard; 19,351 t normal; 20,352 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (726.65 ft / 715.00 ft) x 72.00 ft x (23.00 / 23.92 ft)
 (221.48 m / 217.93 m) x 21.95 m  x (7.01 / 7.29 m)

Armament:
      9 - 9.20" / 234 mm 55.0 cal guns - 420.00lbs / 190.51kg shells, 120 per gun
   Breech loading guns in turret on barbette mounts, 1921 Model
   3 x Triple mounts on centreline ends, majority forward
  1 raised mount - superfiring
      6 - 4.70" / 119 mm 45.0 cal guns - 52.35lbs / 23.75kg shells, 150 per gun
   Anti-air guns in deck and hoist mounts, 1921 Model
   6 x Single mounts on sides, aft deck forward
  6 raised mounts
      16 - 1.57" / 40.0 mm 45.0 cal guns - 2.00lbs / 0.91kg shells, 150 per gun
   Breech loading guns in deck mounts, 1921 Model
   4 x 2 row quad mounts on sides, forward deck aft
  4 raised mounts
      Weight of broadside 4,126 lbs / 1,872 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 4.00" / 102 mm 490.00 ft / 149.35 m 12.00 ft / 3.66 m
 Ends: Unarmoured
   Main Belt covers 105 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  0.80" / 20 mm 490.00 ft / 149.35 m 22.00 ft / 6.71 m

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

   - Armoured deck - multiple decks: 2.00" / 51 mm For and Aft decks
 Forecastle: 2.00" / 51 mm  Quarter deck: 2.00" / 51 mm

   - Conning towers: Forward 4.00" / 102 mm,  Aft 0.00" / 0 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 190,303 shp / 141,966 Kw = 37.00 kts
 Range 6,500nm at 15.00 kts
 Bunker at max displacement = 2,253 tons

Complement:
 819 - 1,066

Cost:
 £4.528 million / $18.112 million

Distribution of weights at normal displacement:
 Armament: 1,122 tons, 5.8 %
 Armour: 3,326 tons, 17.2 %
    - Belts: 965 tons, 5.0 %
    - Torpedo bulkhead: 319 tons, 1.6 %
    - Armament: 557 tons, 2.9 %
    - Armour Deck: 1,423 tons, 7.4 %
    - Conning Tower: 62 tons, 0.3 %
 Machinery: 5,029 tons, 26.0 %
 Hull, fittings & equipment: 7,954 tons, 41.1 %
 Fuel, ammunition & stores: 1,919 tons, 9.9 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   23,565 lbs / 10,689 Kg = 60.5 x 9.2 " / 234 mm shells or 2.5 torpedoes
 Stability (Unstable if below 1.00): 1.08
 Metacentric height 3.6 ft / 1.1 m
 Roll period: 16.0 seconds
 Steadiness - As gun platform (Average = 50 %): 55 %
   - Recoil effect (Restricted arc if above 1.00): 0.79
 Seaboat quality  (Average = 1.00): 1.10

Hull form characteristics:
 Hull has low quarterdeck ,
   an extended bulbous bow and large transom stern
 Block coefficient (normal/deep): 0.572 / 0.579
 Length to Beam Ratio: 9.93 : 1
 'Natural speed' for length: 30.30 kts
 Power going to wave formation at top speed: 61 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 15.00 degrees
 Stern overhang: 2.00 ft / 0.61 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 28.00 %,  36.00 ft / 10.97 m,  29.00 ft / 8.84 m
    - Forward deck: 30.00 %,  29.00 ft / 8.84 m,  29.00 ft / 8.84 m
    - Aft deck: 15.00 %,  29.00 ft / 8.84 m,  29.00 ft / 8.84 m
    - Quarter deck: 27.00 %,  21.00 ft / 6.40 m,  21.00 ft / 6.40 m
    - Average freeboard:  27.62 ft / 8.42 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 146.9 %
  - Above water (accommodation/working, high = better): 257.7 %
 Waterplane Area: 38,202 Square feet or 3,549 Square metres
 Displacement factor (Displacement / loading): 109 %
 Structure weight / hull surface area: 135 lbs/sq ft or 661 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.94
  - Longitudinal: 1.83
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent