The very fast version of the GB/CB/1905

In the early 1970's, I had played with the concept of a very fast version of my friend Cliff's GB/CB/1905 design. I had hoped for as much as 45 knots. This version that I tried today is good for 40 knots, which is the best that I have been able to achieve. I suspect that we might be able to squeeze more by allowing a deeper draft. This is the Springsharp report:

GB/CB/1905 Very Fast, Great Britain Battlecruiser laid down 1905 (Engine 1950)

Displacement:
 24,931 t light; 25,713 t standard; 26,844 t normal; 27,749 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (776.00 ft / 770.00 ft) x 85.00 ft x (29.00 / 29.73 ft)
 (236.52 m / 234.70 m) x 25.91 m  x (8.84 / 9.06 m)

Armament:
      4 - 12.00" / 305 mm 45.0 cal guns - 850.00lbs / 385.55kg shells, 90 per gun
   Breech loading guns in turret on barbette mounts, 1905 Model
   2 x Twin mounts on centreline ends, evenly spread
      9 - 6.00" / 152 mm 50.0 cal guns - 100.00lbs / 45.36kg shells, 150 per gun
   Breech loading guns in deck and hoist mounts, 1905 Model
   8 x Single mounts on centreline, aft deck forward
   1 x Single mount on centreline, aft deck centre
  1 raised mount
      Weight of broadside 4,300 lbs / 1,950 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 4.00" / 102 mm 540.00 ft / 164.59 m 8.00 ft / 2.44 m
 Ends: Unarmoured
 Upper: 4.00" / 102 mm 380.00 ft / 115.82 m 8.00 ft / 2.44 m
   Main Belt covers 108 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.50" / 38 mm 540.00 ft / 164.59 m 29.00 ft / 8.84 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 6.00" / 152 mm 4.00" / 102 mm  6.00" / 152 mm
 2nd: 4.00" / 102 mm 3.00" / 76 mm  4.00" / 102 mm

   - Protected 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 6.00" / 152 mm,  Aft 0.00" / 0 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 6 shafts, 350,831 shp / 261,720 Kw = 40.00 kts
 Range 5,400nm at 15.00 kts
 Bunker at max displacement = 2,036 tons

Complement:
 1,048 - 1,363

Cost:
 £2.481 million / $9.924 million

Distribution of weights at normal displacement:
 Armament: 923 tons, 3.4 %
 Armour: 4,686 tons, 17.5 %
    - Belts: 1,236 tons, 4.6 %
    - Torpedo bulkhead: 869 tons, 3.2 %
    - Armament: 848 tons, 3.2 %
    - Armour Deck: 1,616 tons, 6.0 %
    - Conning Tower: 116 tons, 0.4 %
 Machinery: 8,393 tons, 31.3 %
 Hull, fittings & equipment: 10,929 tons, 40.7 %
 Fuel, ammunition & stores: 1,913 tons, 7.1 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   27,342 lbs / 12,402 Kg = 31.6 x 12.0 " / 305 mm shells or 3.0 torpedoes
 Stability (Unstable if below 1.00): 1.17
 Metacentric height 5.2 ft / 1.6 m
 Roll period: 15.6 seconds
 Steadiness - As gun platform (Average = 50 %): 53 %
   - Recoil effect (Restricted arc if above 1.00): 0.43
 Seaboat quality  (Average = 1.00): 1.06

Hull form characteristics:
 Hull has low quarterdeck ,
   a ram bow and a cruiser stern
 Block coefficient (normal/deep): 0.495 / 0.499
 Length to Beam Ratio: 9.06 : 1
 'Natural speed' for length: 27.75 kts
 Power going to wave formation at top speed: 63 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 0.00 degrees
 Stern overhang: -2.00 ft / -0.61 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 20.00 %,  37.00 ft / 11.28 m,  34.00 ft / 10.36 m
    - Forward deck: 30.00 %,  34.00 ft / 10.36 m,  33.00 ft / 10.06 m
    - Aft deck: 17.00 %,  33.00 ft / 10.06 m,  33.00 ft / 10.06 m
    - Quarter deck: 33.00 %,  25.00 ft / 7.62 m,  25.00 ft / 7.62 m
    - Average freeboard:  30.95 ft / 9.43 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 151.7 %
  - Above water (accommodation/working, high = better): 262.9 %
 Waterplane Area: 43,410 Square feet or 4,033 Square metres
 Displacement factor (Displacement / loading): 105 %
 Structure weight / hull surface area: 153 lbs/sq ft or 748 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.92
  - Longitudinal: 2.07
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent