The GB/CB/1905 design study

This is a design study proposed by my friend Cliff for the GB/CB/1905 design. It is really a better ship than what he decided to use. His design study had a 6in belt, 6-12in and 8-6in guns, and a 31 knot speed (he actually hoped to achieve 31.2 knots). When I used his armouring scheme, the weight exceeded what he had planned for the protection weight. This is the Springsharp report:

GB/CB/1905 design study, Great Britain Battlecruiser laid down 1905 (Engine 1909)

Displacement:
23,431 t light; 24,289 t standard; 27,400 t normal; 29,889 t full load

Dimensions: Length overall / water x beam x draught
770.00 ft / 770.00 ft x 85.00 ft x 26.00 ft (normal load)
234.70 m / 234.70 m x 25.91 m  x 7.92 m

Armament:
     6 - 12.00" / 305 mm guns (3x2 guns), 864.00lbs / 391.90kg shells, 1905 Model
  Breech loading guns in turrets (on barbettes)
  on centreline ends, majority forward, 1 raised mount - superfiring
     8 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1905 Model
  Quick firing guns in deck mounts with hoists
  on side, evenly spread
Weight of broadside 6,048 lbs / 2,743 kg
Shells per gun, main battery: 90

Armour:
  - Belts:  Width (max) Length (avg)  Height (avg)
Main: 6.00" / 152 mm 465.00 ft / 141.73 m 8.00 ft / 2.44 m
Ends: Unarmoured
Upper: 4.00" / 102 mm 465.00 ft / 141.73 m 8.00 ft / 2.44 m
  Main Belt covers 93 % of normal length
  Main belt does not fully cover magazines and engineering spaces

  - Torpedo Bulkhead:
 2.00" / 51 mm 465.00 ft / 141.73 m 26.00 ft / 7.92 m

  - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 10.0" / 254 mm 6.00" / 152 mm  8.00" / 203 mm
2nd: 4.00" / 102 mm 4.00" / 102 mm  4.00" / 102 mm

  - Armour deck: 2.00" / 51 mm, Conning tower: 6.00" / 152 mm

Machinery:
Oil fired boilers, steam turbines,
Direct drive, 4 shafts, 139,103 shp / 103,771 Kw = 31.50 kts
Range 7,500nm at 15.00 kts
Bunker at max displacement = 5,600 tons

Complement:
1,064 - 1,384

Cost:
£2.340 million / $9.361 million

Distribution of weights at normal displacement:
Armament: 756 tons, 2.8 %
Armour: 5,731 tons, 20.9 %
   - Belts: 1,586 tons, 5.8 %
   - Torpedo bulkhead: 895 tons, 3.3 %
   - Armament: 1,421 tons, 5.2 %
   - Armour Deck: 1,712 tons, 6.2 %
   - Conning Tower: 117 tons, 0.4 %
Machinery: 6,323 tons, 23.1 %
Hull, fittings & equipment: 10,622 tons, 38.8 %
Fuel, ammunition & stores: 3,969 tons, 14.5 %
Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
  35,342 lbs / 16,031 Kg = 40.9 x 12.0 " / 305 mm shells or 4.2 torpedoes
Stability (Unstable if below 1.00): 1.21
Metacentric height 5.6 ft / 1.7 m
Roll period: 15.1 seconds
Steadiness - As gun platform (Average = 50 %): 66 %
  - Recoil effect (Restricted arc if above 1.00): 0.53
Seaboat quality  (Average = 1.00): 1.32

Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.564
Length to Beam Ratio: 9.06 : 1
'Natural speed' for length: 27.75 kts
Power going to wave formation at top speed: 52 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): -2.00 degrees
Stern overhang: -2.00 ft / -0.61 m
Freeboard (% = measuring location as a percentage of overall length):
   - Stem:  32.00 ft / 9.75 m
   - Forecastle (20 %): 28.00 ft / 8.53 m
   - Mid (67 %):  28.00 ft / 8.53 m (20.00 ft / 6.10 m aft of break)
   - Quarterdeck (15 %): 20.00 ft / 6.10 m
   - Stern:  20.00 ft / 6.10 m
   - Average freeboard: 25.68 ft / 7.83 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 125.2 %
 - Above water (accommodation/working, high = better): 213.5 %
Waterplane Area: 46,261 Square feet or 4,298 Square metres
Displacement factor (Displacement / loading): 112 %
Structure weight / hull surface area: 152 lbs/sq ft or 741 Kg/sq metre
Hull strength (Relative):
 - Cross-sectional: 0.98
 - Longitudinal: 1.20
 - Overall: 1.00
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is excellent
Good seaboat, rides out heavy weather easily