Another version of my friend Cliff's BBX design

The BBX design was intended for building, starting in 1915, in the wargame campaign that we played back in 1971. This was my friend Cliff's concept for a dominant battleship. In this page, in the Red Book, there is a pencil drawing that shows the citadel length and the intended power and speed. The speed and power calculations, in this case, were extremely accurate. I had calculated 179,000 SHP would produce a speed of 28.3 knots. I Springsharp, the speed of 28.4 knots is obtained using 178,280 SHP. Considering that the original was estimated using comparison ships, that was quite acceptable. The armament is 9-18in BLR and 24-5in QF guns. The armour basis is 18in, with an 8in deck and 8in torpedo protection. A range of 10,000nm at 15 knots was possible, due to the rather low protection weight. This is the Springsharp report:

GB/BB/1915 BBX, Great Britain Battleship laid down 1915 (Engine 1937)

Displacement:
 64,590 t light; 67,422 t standard; 71,500 t normal; 74,762 t full load

Dimensions: Length overall / water x beam x draught
 801.62 ft / 800.00 ft x 135.00 ft x 37.00 ft (normal load)
 244.34 m / 243.84 m x 41.15 m  x 11.28 m

Armament:
      9 - 18.00" / 457 mm guns (3x3 guns), 2,916.00lbs / 1,322.68kg shells, 1915 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, majority forward, 1 raised mount - superfiring
      24 - 5.00" / 127 mm guns (12x2 guns), 62.50lbs / 28.35kg shells, 1915 Model
   Quick firing guns in turrets (on barbettes)
   on side, all amidships, 4 raised mounts - superfiring
 Weight of broadside 27,744 lbs / 12,584 kg
 Shells per gun, main battery: 90

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 18.0" / 457 mm 465.00 ft / 141.73 m 19.00 ft / 5.79 m
 Ends: Unarmoured
   Main Belt covers 89 % of normal length

   - Torpedo Bulkhead:
  8.00" / 203 mm 465.00 ft / 141.73 m 36.00 ft / 10.97 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 18.0" / 457 mm 12.0" / 305 mm  18.0" / 457 mm
 2nd: 5.00" / 127 mm 5.00" / 127 mm  5.00" / 127 mm

   - Armour deck: 8.00" / 203 mm, Conning tower: 18.00" / 457 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 178,280 shp / 132,997 Kw = 28.40 kts
 Range 10,000nm at 15.00 kts
 Bunker at max displacement = 7,340 tons

Complement:
 2,186 - 2,842

Cost:
 £8.532 million / $34.127 million

Distribution of weights at normal displacement:
 Armament: 3,468 tons, 4.9 %
 Armour: 30,992 tons, 43.3 %
    - Belts: 7,235 tons, 10.1 %
    - Torpedo bulkhead: 4,955 tons, 6.9 %
    - Armament: 6,154 tons, 8.6 %
    - Armour Deck: 11,980 tons, 16.8 %
    - Conning Tower: 668 tons, 0.9 %
 Machinery: 4,941 tons, 6.9 %
 Hull, fittings & equipment: 25,189 tons, 35.2 %
 Fuel, ammunition & stores: 6,910 tons, 9.7 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   114,464 lbs / 51,920 Kg = 39.3 x 18.0 " / 457 mm shells or 27.2 torpedoes
 Stability (Unstable if below 1.00): 1.19
 Metacentric height 10.7 ft / 3.3 m
 Roll period: 17.3 seconds
 Steadiness - As gun platform (Average = 50 %): 53 %
   - Recoil effect (Restricted arc if above 1.00): 0.37
 Seaboat quality  (Average = 1.00): 1.06

Hull form characteristics:
 Hull has a flush deck
 Block coefficient: 0.626
 Length to Beam Ratio: 5.93 : 1
 'Natural speed' for length: 28.28 kts
 Power going to wave formation at top speed: 53 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 3.00 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): 69.6 %
  - Above water (accommodation/working, high = better): 162.2 %
 Waterplane Area: 80,943 Square feet or 7,520 Square metres
 Displacement factor (Displacement / loading): 104 %
 Structure weight / hull surface area: 238 lbs/sq ft or 1,164 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.97
  - Longitudinal: 1.40
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is excellent
 Room for accommodation and workspaces is excellent