The 31-knot version of the GB/CB/1937

I thought that 29 knots was too slow for the GB/CB/1937, so I increased the draft and displacement to make 31 knots possible. at 29 knots, the battlecruiser did not have a sufficient advantage over the 27-knot battleship. If we had a 29-knot battlecruiser, we should increase the belt thickness to more than 11 inches. This is the Springsharp report for the 31-knot version with a 11in belt:

GB/CB/1937, Great Britain Battlecruiser laid down 1937 (Engine 1941)

Displacement:
 41,675 t light; 43,757 t standard; 45,700 t normal; 47,254 t full load

Dimensions: Length overall / water x beam x draught
 852.17 ft / 850.00 ft x 108.00 ft x 31.00 ft (normal load)
 259.74 m / 259.08 m x 32.92 m  x 9.45 m

Armament:
      9 - 16.00" / 406 mm guns (3x3 guns), 2,048.00lbs / 928.96kg shells, 1937 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, majority forward, 1 raised mount - superfiring
      16 - 6.00" / 152 mm guns (8x2 guns), 108.00lbs / 48.99kg shells, 1937 Model
   Quick firing guns in turrets (on barbettes)
   on side, evenly spread, 4 raised mounts
      8 - 4.70" / 119 mm guns (4x2 guns), 51.91lbs / 23.55kg shells, 1937 Model
   Anti-aircraft guns in deck mounts 
   on centreline, evenly spread
      16 - 1.57" / 40.0 mm guns (2x8 guns), 1.95lbs / 0.88kg shells, 1937 Model
   Anti-aircraft guns in deck mounts 
   on side, all amidships, 1 raised mount - superfiring
      8 - 1.57" / 40.0 mm guns in single mounts, 1.95lbs / 0.88kg shells, 1937 Model
   Anti-aircraft guns in deck mount 
   on side, evenly spread, all raised mounts
 Weight of broadside 20,622 lbs / 9,354 kg
 Shells per gun, main battery: 100

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 11.0" / 279 mm 570.00 ft / 173.74 m 16.00 ft / 4.88 m
 Ends: Unarmoured
   Main Belt covers 103 % of normal length

   - Torpedo Bulkhead:
  3.00" / 76 mm 570.00 ft / 173.74 m 31.00 ft / 9.45 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 12.0" / 305 mm 8.00" / 203 mm  12.0" / 305 mm
 2nd: 5.00" / 127 mm 5.00" / 127 mm  5.00" / 127 mm

   - Armour deck: 4.00" / 102 mm, Conning tower: 12.00" / 305 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 153,523 shp / 114,528 Kw = 31.00 kts
 Range 6,500nm at 15.00 kts
 Bunker at max displacement = 3,498 tons

Complement:
 1,562 - 2,031

Cost:
 £22.865 million / $91.461 million

Distribution of weights at normal displacement:
 Armament: 2,578 tons, 5.6 %
 Armour: 15,399 tons, 33.7 %
    - Belts: 4,259 tons, 9.3 %
    - Torpedo bulkhead: 1,961 tons, 4.3 %
    - Armament: 3,855 tons, 8.4 %
    - Armour Deck: 4,993 tons, 10.9 %
    - Conning Tower: 330 tons, 0.7 %
 Machinery: 4,057 tons, 8.9 %
 Hull, fittings & equipment: 19,641 tons, 43.0 %
 Fuel, ammunition & stores: 4,025 tons, 8.8 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   66,100 lbs / 29,982 Kg = 32.3 x 16.0 " / 406 mm shells or 10.7 torpedoes
 Stability (Unstable if below 1.00): 1.11
 Metacentric height 6.9 ft / 2.1 m
 Roll period: 17.3 seconds
 Steadiness - As gun platform (Average = 50 %): 55 %
   - Recoil effect (Restricted arc if above 1.00): 0.68
 Seaboat quality  (Average = 1.00): 1.11

Hull form characteristics:
 Hull has a flush deck
   and transom stern
 Block coefficient: 0.562
 Length to Beam Ratio: 7.87 : 1
 'Natural speed' for length: 33.68 kts
 Power going to wave formation at top speed: 51 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 4.00 degrees
 Stern overhang: 0.00 ft / 0.00 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  31.00 ft / 9.45 m
    - Forecastle (20 %): 23.00 ft / 7.01 m
    - Mid (50 %):  23.00 ft / 7.01 m
    - Quarterdeck (15 %): 23.00 ft / 7.01 m
    - Stern:  23.00 ft / 7.01 m
    - Average freeboard: 23.64 ft / 7.21 m
 Ship tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 87.9 %
  - Above water (accommodation/working, high = better): 189.2 %
 Waterplane Area: 67,475 Square feet or 6,269 Square metres
 Displacement factor (Displacement / loading): 104 %
 Structure weight / hull surface area: 216 lbs/sq ft or 1,053 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.98
  - Longitudinal: 1.16
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is adequate
 Room for accommodation and workspaces is excellent