My attempt at a 1918 British light cruiser

Perhaps this is anachronistic, but I thought that having four twin 6in turrets was not unreasonable for a ship laid down in 1918. This is meant to be an incremental advance over my GB/CL/1916 design. It is not a great advance, except for the turrets. There is some increase in speed and range. I couldn't resist a Springsharp-specific "hack" of increasing the draft for more strength and increased seakeeping. This is the Springsharp report:

GB/CL/1918, Great Britain Light Cruiser laid down 1918

Displacement:
 8,996 t light; 9,290 t standard; 10,200 t normal; 10,928 t full load

Dimensions: Length overall / water x beam x draught
 556.36 ft / 555.00 ft x 56.00 ft x 20.00 ft (normal load)
 169.58 m / 169.16 m x 17.07 m  x 6.10 m

Armament:
      8 - 6.00" / 152 mm guns (4x2 guns), 108.00lbs / 48.99kg shells, 1918 Model
   Quick firing guns in turrets (on barbettes)
   on centreline ends, evenly spread, 2 raised mounts - superfiring
      4 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1918 Model
   Anti-aircraft guns in deck mounts with hoists
   on side, all amidships
      16 - 1.57" / 40.0 mm guns (4x4 guns), 1.95lbs / 0.89kg shells, 1918 Model
   Breech loading guns in deck mounts 
   on side ends, evenly spread
 Weight of broadside 1,023 lbs / 464 kg
 Shells per gun, main battery: 150
 8 - 21.0" / 533.4 mm above water torpedoes, 21 - 21.0" / 533.4 mm submerged torpedo tubes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 4.00" / 102 mm 425.00 ft / 129.54 m 12.00 ft / 3.66 m
 Ends: Unarmoured
   Main Belt covers 118 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 2.00" / 51 mm       -   2.00" / 51 mm

   - Armour deck: 2.00" / 51 mm, Conning tower: 4.00" / 102 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 97,206 shp / 72,515 Kw = 32.50 kts
 Range 5,800nm at 15.00 kts
 Bunker at max displacement = 1,639 tons

Complement:
 506 - 659

Cost:
 £1.826 million / $7.306 million

Distribution of weights at normal displacement:
 Armament: 128 tons, 1.3 %
 Armour: 1,835 tons, 18.0 %
    - Belts: 832 tons, 8.2 %
    - Torpedo bulkhead: 0 tons, 0.0 %
    - Armament: 142 tons, 1.4 %
    - Armour Deck: 821 tons, 8.0 %
    - Conning Tower: 41 tons, 0.4 %
 Machinery: 3,507 tons, 34.4 %
 Hull, fittings & equipment: 3,526 tons, 34.6 %
 Fuel, ammunition & stores: 1,204 tons, 11.8 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   4,601 lbs / 2,087 Kg = 42.6 x 6.0 " / 152 mm shells or 0.7 torpedoes
 Stability (Unstable if below 1.00): 1.28
 Metacentric height 3.3 ft / 1.0 m
 Roll period: 13.0 seconds
 Steadiness - As gun platform (Average = 50 %): 53 %
   - Recoil effect (Restricted arc if above 1.00): 0.32
 Seaboat quality  (Average = 1.00): 1.05

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.574
 Length to Beam Ratio: 9.91 : 1
 'Natural speed' for length: 23.56 kts
 Power going to wave formation at top speed: 61 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 3.00 degrees
 Stern overhang: -2.00 ft / -0.61 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  26.00 ft / 7.92 m
    - Forecastle (20 %): 23.00 ft / 7.01 m
    - Mid (67 %):  23.00 ft / 7.01 m (15.00 ft / 4.57 m aft of break)
    - Quarterdeck (15 %): 15.00 ft / 4.57 m
    - Stern:  15.00 ft / 4.57 m
    - Average freeboard: 20.60 ft / 6.28 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 169.4 %
  - Above water (accommodation/working, high = better): 142.8 %
 Waterplane Area: 22,191 Square feet or 2,062 Square metres
 Displacement factor (Displacement / loading): 103 %
 Structure weight / hull surface area: 94 lbs/sq ft or 458 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.95
  - Longitudinal: 1.56
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

A GB/CL/1916 light cruiser design

Continuing this design series, this is my first attempt at a 1916 British light cruiser. The armament is 9-6in QF, 4-3in AA, 12-2pdr AA guns, and 8-21in TT (above water). The armour basis is still 4in with a 2in deck. The maximum speed has risen to 32 knots and the range is 5,400nm at 15 knots. This is the Springsharp report:

GB/CL/1916, Great Britain Light Cruiser laid down 1916

Displacement:
 8,704 t light; 8,992 t standard; 9,900 t normal; 10,626 t full load

Dimensions: Length overall / water x beam x draught
 546.36 ft / 545.00 ft x 55.00 ft x 18.00 ft (normal load)
 166.53 m / 166.12 m x 16.76 m  x 5.49 m

Armament:
      9 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1916 Model
   Quick firing guns in deck mounts with hoists
   on centreline ends, majority forward, 2 raised mounts - superfiring
      4 - 3.00" / 76.2 mm guns in single mounts, 13.50lbs / 6.12kg shells, 1916 Model
   Anti-aircraft guns in deck mounts with hoists
   on side, all amidships
      12 - 1.57" / 40.0 mm guns (3x4 guns), 2.00lbs / 0.91kg shells, 1916 Model
   Breech loading guns in deck mounts 
   on side ends, majority aft
 Weight of broadside 1,050 lbs / 476 kg
 Shells per gun, main battery: 150
 8 - 21.0" / 533.4 mm above water torpedoes, 21 - 21.0" / 533.4 mm submerged torpedo tubes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 4.00" / 102 mm 420.00 ft / 128.02 m 12.00 ft / 3.66 m
 Ends: Unarmoured
   Main Belt covers 119 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 2.00" / 51 mm       -   2.00" / 51 mm

   - Armour deck: 2.00" / 51 mm, Conning tower: 4.00" / 102 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 93,429 shp / 69,698 Kw = 32.00 kts
 Range 5,400nm at 15.00 kts
 Bunker at max displacement = 1,634 tons

Complement:
 496 - 645

Cost:
 £1.476 million / $5.905 million

Distribution of weights at normal displacement:
 Armament: 131 tons, 1.3 %
 Armour: 1,774 tons, 17.9 %
    - Belts: 823 tons, 8.3 %
    - Torpedo bulkhead: 0 tons, 0.0 %
    - Armament: 68 tons, 0.7 %
    - Armour Deck: 844 tons, 8.5 %
    - Conning Tower: 40 tons, 0.4 %
 Machinery: 3,481 tons, 35.2 %
 Hull, fittings & equipment: 3,318 tons, 33.5 %
 Fuel, ammunition & stores: 1,196 tons, 12.1 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   4,353 lbs / 1,974 Kg = 40.3 x 6.0 " / 152 mm shells or 0.7 torpedoes
 Stability (Unstable if below 1.00): 1.34
 Metacentric height 3.4 ft / 1.0 m
 Roll period: 12.5 seconds
 Steadiness - As gun platform (Average = 50 %): 53 %
   - Recoil effect (Restricted arc if above 1.00): 0.31
 Seaboat quality  (Average = 1.00): 1.06

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.642
 Length to Beam Ratio: 9.91 : 1
 'Natural speed' for length: 23.35 kts
 Power going to wave formation at top speed: 62 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 3.00 degrees
 Stern overhang: -2.00 ft / -0.61 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  26.00 ft / 7.92 m
    - Forecastle (20 %): 23.00 ft / 7.01 m
    - Mid (67 %):  23.00 ft / 7.01 m (15.00 ft / 4.57 m aft of break)
    - Quarterdeck (15 %): 15.00 ft / 4.57 m
    - Stern:  15.00 ft / 4.57 m
    - Average freeboard: 20.60 ft / 6.28 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 176.2 %
  - Above water (accommodation/working, high = better): 148.5 %
 Waterplane Area: 22,799 Square feet or 2,118 Square metres
 Displacement factor (Displacement / loading): 101 %
 Structure weight / hull surface area: 89 lbs/sq ft or 432 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.95
  - Longitudinal: 1.51
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

A new GB/CL/1914 design

This is inspired by the sort of ship the Russians were building at the beginning of WWI. I wanted a multi-purpose light cruiser with decent protection and armament with a 30 knot speed. The armament is 7-6in QF, 2-3in AA, and 4-21in TT. The belt is 4in and the deck is 2in. The range is 5,000nm at 15 knots. This is the Springsharp report:

GB/CL/1914, Great Britain Light Cruiser laid down 1914

Displacement:
 6,618 t light; 6,836 t standard; 7,600 t normal; 8,211 t full load

Dimensions: Length overall / water x beam x draught
 513.31 ft / 512.00 ft x 52.00 ft x 18.00 ft (normal load)
 156.46 m / 156.06 m x 15.85 m  x 5.49 m

Armament:
      7 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1914 Model
   Quick firing guns in deck mounts with hoists
   on centreline ends, majority forward, 2 raised mounts - superfiring
      2 - 3.00" / 76.2 mm guns in single mounts, 13.50lbs / 6.12kg shells, 1914 Model
   Anti-aircraft guns in deck mounts with hoists
   on side, all amidships
 Weight of broadside 783 lbs / 355 kg
 Shells per gun, main battery: 150
 4 - 21.0" / 533.4 mm above water torpedoes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 4.00" / 102 mm 390.00 ft / 118.87 m 12.00 ft / 3.66 m
 Ends: Unarmoured
   Main Belt covers 117 % of normal length

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 2.00" / 51 mm       -   2.00" / 51 mm

   - Armour deck: 2.00" / 51 mm, Conning tower: 4.00" / 102 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 59,938 shp / 44,714 Kw = 30.00 kts
 Range 5,000nm at 15.00 kts
 Bunker at max displacement = 1,376 tons

Complement:
 406 - 529

Cost:
 £0.811 million / $3.243 million

Distribution of weights at normal displacement:
 Armament: 98 tons, 1.3 %
 Armour: 1,540 tons, 20.3 %
    - Belts: 764 tons, 10.0 %
    - Torpedo bulkhead: 0 tons, 0.0 %
    - Armament: 53 tons, 0.7 %
    - Armour Deck: 691 tons, 9.1 %
    - Conning Tower: 33 tons, 0.4 %
 Machinery: 2,309 tons, 30.4 %
 Hull, fittings & equipment: 2,671 tons, 35.1 %
 Fuel, ammunition & stores: 982 tons, 12.9 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   8,682 lbs / 3,938 Kg = 80.4 x 6.0 " / 152 mm shells or 1.2 torpedoes
 Stability (Unstable if below 1.00): 1.28
 Metacentric height 2.9 ft / 0.9 m
 Roll period: 12.8 seconds
 Steadiness - As gun platform (Average = 50 %): 65 %
   - Recoil effect (Restricted arc if above 1.00): 0.33
 Seaboat quality  (Average = 1.00): 1.30

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.555
 Length to Beam Ratio: 9.85 : 1
 'Natural speed' for length: 22.63 kts
 Power going to wave formation at top speed: 58 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 3.00 degrees
 Stern overhang: -2.00 ft / -0.61 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  25.00 ft / 7.62 m
    - Forecastle (20 %): 22.00 ft / 6.71 m
    - Mid (67 %):  22.00 ft / 6.71 m (14.00 ft / 4.27 m aft of break)
    - Quarterdeck (15 %): 14.00 ft / 4.27 m
    - Stern:  14.00 ft / 4.27 m
    - Average freeboard: 19.60 ft / 5.97 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 108.8 %
  - Above water (accommodation/working, high = better): 155.3 %
 Waterplane Area: 18,669 Square feet or 1,734 Square metres
 Displacement factor (Displacement / loading): 109 %
 Structure weight / hull surface area: 83 lbs/sq ft or 407 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.94
  - Longitudinal: 1.75
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is adequate
 Room for accommodation and workspaces is excellent
 Good seaboat, rides out heavy weather easily

A really super heavy cruiser for 1923

I am not sure what to think of 10in guns on a heavy cruiser, but I tried them on a 1923 design to be built if there were no Washington Naval Treaty. This is another flush-decked ship with triple turrets for the main armament. The armament in this case is like other 1923 ships, in that it is the start of a modern approach with DP guns for the secondary armament. The armament is 9-10in BLR, 8-4.7in DP, and 36-2pdr AA in quad mounts. There are no torpedo tubes. The armour basis is 6in with a thick 3in deck. There is also a 1in torpedo bulkhead. The range has grown to 7,500nm at 15 knots. The maximum speed has moved up to 33.5 knots, thanks to the transom stern. This is the Springsharp report:

GB/CA/1923, Great Britain Heavy Cruiser laid down 1923

Displacement:
 20,042 t light; 20,746 t standard; 22,400 t normal; 23,723 t full load

Dimensions: Length overall / water x beam x draught
 718.10 ft / 714.00 ft x 75.00 ft x 25.00 ft (normal load)
 218.88 m / 217.63 m x 22.86 m  x 7.62 m

Armament:
      9 - 10.00" / 254 mm guns (3x3 guns), 500.00lbs / 226.80kg shells, 1923 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, majority forward, 1 raised mount - superfiring
      8 - 4.70" / 119 mm guns (4x2 guns), 51.91lbs / 23.55kg shells, 1923 Model
   Dual purpose guns in turrets (on barbettes)
   on side, all amidships, all raised mounts - superfiring
      36 - 1.57" / 40.0 mm guns (9x4 guns), 2.00lbs / 0.91kg shells, 1923 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread
 Weight of broadside 4,987 lbs / 2,262 kg
 Shells per gun, main battery: 90

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 6.00" / 152 mm 620.00 ft / 188.98 m 16.00 ft / 4.88 m
 Ends: Unarmoured
   Main Belt covers 134 % of normal length

   - Torpedo Bulkhead:
  1.00" / 25 mm 620.00 ft / 188.98 m 23.00 ft / 7.01 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: 1.00" / 25 mm 1.00" / 25 mm  1.00" / 25 mm
 3rd: 1.00" / 25 mm       -         -

   - Armour deck: 3.00" / 76 mm, Conning tower: 6.00" / 152 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 141,351 shp / 105,448 Kw = 33.50 kts
 Range 7,500nm at 15.00 kts
 Bunker at max displacement = 2,977 tons

Complement:
 915 - 1,190

Cost:
 £5.488 million / $21.950 million

Distribution of weights at normal displacement:
 Armament: 623 tons, 2.8 %
 Armour: 6,196 tons, 27.7 %
    - Belts: 2,387 tons, 10.7 %
    - Torpedo bulkhead: 528 tons, 2.4 %
    - Armament: 944 tons, 4.2 %
    - Armour Deck: 2,235 tons, 10.0 %
    - Conning Tower: 103 tons, 0.5 %
 Machinery: 4,724 tons, 21.1 %
 Hull, fittings & equipment: 8,499 tons, 37.9 %
 Fuel, ammunition & stores: 2,358 tons, 10.5 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   29,961 lbs / 13,590 Kg = 59.9 x 10.0 " / 254 mm shells or 3.6 torpedoes
 Stability (Unstable if below 1.00): 1.15
 Metacentric height 4.2 ft / 1.3 m
 Roll period: 15.3 seconds
 Steadiness - As gun platform (Average = 50 %): 52 %
   - Recoil effect (Restricted arc if above 1.00): 0.62
 Seaboat quality  (Average = 1.00): 1.04

Hull form characteristics:
 Hull has a flush deck
   and transom stern
 Block coefficient: 0.586
 Length to Beam Ratio: 9.52 : 1
 'Natural speed' for length: 30.33 kts
 Power going to wave formation at top speed: 57 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 4.00 degrees
 Stern overhang: 2.00 ft / 0.61 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  30.00 ft / 9.14 m
    - Forecastle (20 %): 24.00 ft / 7.32 m
    - Mid (50 %):  24.00 ft / 7.32 m
    - Quarterdeck (15 %): 24.00 ft / 7.32 m
    - Stern:  24.00 ft / 7.32 m
    - Average freeboard: 24.48 ft / 7.46 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 122.2 %
  - Above water (accommodation/working, high = better): 201.1 %
 Waterplane Area: 40,261 Square feet or 3,740 Square metres
 Displacement factor (Displacement / loading): 109 %
 Structure weight / hull surface area: 139 lbs/sq ft or 679 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.97
  - Longitudinal: 1.28
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

A super ship: the GB/CA/1921

The GB/CA/1921 seems like a super ship, compared to its predecessor designs. This ship has 9-9.2in BLR, 12-4.7in QF, 6-4.7in AA, and 32-2pdr AA guns. The armour basis is 6in with a 2.5in deck. The maximum speed is 33 knots with a range of 6,500nm at 15 knots. The hull is flush-decked and has a transom stern. This is the Springsharp report:

GB/CA/1921, Great Britain Heavy Cruiser laid down 1921

Displacement:
 17,722 t light; 18,434 t standard; 19,800 t normal; 20,893 t full load

Dimensions: Length overall / water x beam x draught
 678.03 ft / 674.00 ft x 69.00 ft x 24.00 ft (normal load)
 206.66 m / 205.44 m x 21.03 m  x 7.32 m

Armament:
      9 - 9.20" / 234 mm guns (3x3 guns), 389.34lbs / 176.60kg shells, 1921 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, majority forward, 1 raised mount - superfiring
      12 - 4.70" / 119 mm guns in single mounts, 51.91lbs / 23.55kg shells, 1921 Model
   Quick firing guns in deck mounts with hoists
   on side, all amidships, 4 raised mounts - superfiring
      6 - 4.70" / 119 mm guns in single mounts, 51.91lbs / 23.55kg shells, 1921 Model
   Anti-aircraft guns in deck mounts with hoists
   on side, evenly spread
      32 - 1.57" / 40.0 mm guns (8x4 guns), 1.95lbs / 0.89kg shells, 1921 Model
   Anti-aircraft guns in deck mounts 
   on side ends, evenly spread
 Weight of broadside 4,501 lbs / 2,042 kg
 Shells per gun, main battery: 120

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 6.00" / 152 mm 595.00 ft / 181.36 m 16.00 ft / 4.88 m
 Ends: Unarmoured
   Main Belt covers 136 % of normal length

   - Torpedo Bulkhead:
  1.00" / 25 mm 595.00 ft / 181.36 m 21.00 ft / 6.40 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: 2.00" / 51 mm       -   2.00" / 51 mm
 4th: 1.00" / 25 mm       -         -

   - Armour deck: 2.50" / 64 mm, Conning tower: 6.00" / 152 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 127,925 shp / 95,432 Kw = 33.00 kts
 Range 6,500nm at 15.00 kts
 Bunker at max displacement = 2,459 tons

Complement:
 833 - 1,084

Cost:
 £4.352 million / $17.407 million

Distribution of weights at normal displacement:
 Armament: 563 tons, 2.8 %
 Armour: 5,369 tons, 27.1 %
    - Belts: 2,286 tons, 11.5 %
    - Torpedo bulkhead: 462 tons, 2.3 %
    - Armament: 854 tons, 4.3 %
    - Armour Deck: 1,672 tons, 8.4 %
    - Conning Tower: 95 tons, 0.5 %
 Machinery: 4,405 tons, 22.2 %
 Hull, fittings & equipment: 7,385 tons, 37.3 %
 Fuel, ammunition & stores: 2,078 tons, 10.5 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   25,139 lbs / 11,403 Kg = 64.6 x 9.2 " / 234 mm shells or 2.9 torpedoes
 Stability (Unstable if below 1.00): 1.13
 Metacentric height 3.6 ft / 1.1 m
 Roll period: 15.3 seconds
 Steadiness - As gun platform (Average = 50 %): 53 %
   - Recoil effect (Restricted arc if above 1.00): 0.76
 Seaboat quality  (Average = 1.00): 1.07

Hull form characteristics:
 Hull has a flush deck
   and transom stern
 Block coefficient: 0.621
 Length to Beam Ratio: 9.77 : 1
 'Natural speed' for length: 29.32 kts
 Power going to wave formation at top speed: 59 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 4.00 degrees
 Stern overhang: 2.00 ft / 0.61 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  29.00 ft / 8.84 m
    - Forecastle (20 %): 24.00 ft / 7.32 m
    - Mid (67 %):  24.00 ft / 7.32 m
    - Quarterdeck (15 %): 24.00 ft / 7.32 m
    - Stern:  24.00 ft / 7.32 m
    - Average freeboard: 24.40 ft / 7.44 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 132.6 %
  - Above water (accommodation/working, high = better): 198.5 %
 Waterplane Area: 36,162 Square feet or 3,360 Square metres
 Displacement factor (Displacement / loading): 106 %
 Structure weight / hull surface area: 130 lbs/sq ft or 634 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.97
  - Longitudinal: 1.42
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

The British 1918 heavy cruiser worked much better

Like the 1916 design, the 1918 British heavy cruiser design, continuing the design series, has 8-9.2in guns. It also has 12-4.7in QF, 4-4.7in AA, and 16-2pdr AA guns. Again, there are no torpedo tubes. The armour basis is 4in, although there are 5in turret faces on the 9.2in guns. The speed is increased to 32 knots. As this design series is pretty conservative, I did not try for a higher speed. The range is increased to 5,400nm at a cruising speed of 15 knots. This is the Springsharp report:

GB/CA/1916, Great Britain Heavy Cruiser laid down 1918

Displacement:
 14,648 t light; 15,255 t standard; 16,400 t normal; 17,316 t full load

Dimensions: Length overall / water x beam x draught
 655.96 ft / 654.00 ft x 66.00 ft x 23.00 ft (normal load)
 199.94 m / 199.34 m x 20.12 m  x 7.01 m

Armament:
      8 - 9.20" / 234 mm guns (4x2 guns), 389.34lbs / 176.60kg shells, 1918 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 2 raised mounts - superfiring
      12 - 4.70" / 119 mm guns in single mounts, 51.91lbs / 23.55kg shells, 1918 Model
   Quick firing guns in deck mounts with hoists
   on side, all amidships, 4 raised mounts - superfiring
      4 - 4.70" / 119 mm guns in single mounts, 51.91lbs / 23.55kg shells, 1918 Model
   Anti-aircraft guns in deck mounts with hoists
   on side, evenly spread
      16 - 1.57" / 40.0 mm guns (4x4 guns), 1.95lbs / 0.89kg shells, 1918 Model
   Anti-aircraft guns in deck mounts 
   on side ends, evenly spread
 Weight of broadside 3,977 lbs / 1,804 kg
 Shells per gun, main battery: 120

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 4.00" / 102 mm 575.00 ft / 175.26 m 16.00 ft / 4.88 m
 Ends: Unarmoured
   Main Belt covers 135 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.00" / 25 mm 575.00 ft / 175.26 m 21.00 ft / 6.40 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 5.00" / 127 mm 3.00" / 76 mm  4.00" / 102 mm
 2nd: 2.00" / 51 mm       -   2.00" / 51 mm
 4th: 1.00" / 25 mm       -         -

   - Armour deck: 2.00" / 51 mm, Conning tower: 4.00" / 102 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 114,044 shp / 85,077 Kw = 32.00 kts
 Range 5,400nm at 15.00 kts
 Bunker at max displacement = 2,062 tons

Complement:
 723 - 941

Cost:
 £3.012 million / $12.050 million

Distribution of weights at normal displacement:
 Armament: 497 tons, 3.0 %
 Armour: 3,740 tons, 22.8 %
    - Belts: 1,470 tons, 9.0 %
    - Torpedo bulkhead: 447 tons, 2.7 %
    - Armament: 624 tons, 3.8 %
    - Armour Deck: 1,144 tons, 7.0 %
    - Conning Tower: 56 tons, 0.3 %
 Machinery: 4,114 tons, 25.1 %
 Hull, fittings & equipment: 6,297 tons, 38.4 %
 Fuel, ammunition & stores: 1,752 tons, 10.7 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   17,873 lbs / 8,107 Kg = 45.9 x 9.2 " / 234 mm shells or 2.2 torpedoes
 Stability (Unstable if below 1.00): 1.15
 Metacentric height 3.5 ft / 1.1 m
 Roll period: 14.9 seconds
 Steadiness - As gun platform (Average = 50 %): 54 %
   - Recoil effect (Restricted arc if above 1.00): 0.80
 Seaboat quality  (Average = 1.00): 1.08

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.578
 Length to Beam Ratio: 9.91 : 1
 'Natural speed' for length: 25.57 kts
 Power going to wave formation at top speed: 56 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 4.00 degrees
 Stern overhang: -2.00 ft / -0.61 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  28.00 ft / 8.53 m
    - Forecastle (20 %): 25.00 ft / 7.62 m
    - Mid (67 %):  25.00 ft / 7.62 m (17.00 ft / 5.18 m aft of break)
    - Quarterdeck (15 %): 17.00 ft / 5.18 m
    - Stern:  17.00 ft / 5.18 m
    - Average freeboard: 22.60 ft / 6.89 m
 Ship tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 150.1 %
  - Above water (accommodation/working, high = better): 185.7 %
 Waterplane Area: 30,931 Square feet or 2,874 Square metres
 Displacement factor (Displacement / loading): 103 %
 Structure weight / hull surface area: 126 lbs/sq ft or 616 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.97
  - Longitudinal: 1.29
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

A 1916 British 8-in gun cruiser

I tried a 1916 British 8-in gun cruiser, but the armour situation seems very strange. Even with a complete belt, I was not able to satisfy Springsharp, so I shorted the belt to a more modest length. The armament is 8-8in BLR, 8-4.7in QF, 2-4in AA, and 12-2pdr AA guns. There are no torpedo tubes, even though there could have been. The belt is still 4in and the deck is 2in. The maximum speed is 31 knots with a 15 knot cruising speed for a range of 4,800nm. I suspect that there is some design flaw, but I do not see what it is. This is the Sprinsharp report:

GB/CA/1916, Great Britain Heavy Cruiser laid down 1916

Displacement:
 12,989 t light; 13,529 t standard; 14,550 t normal; 15,367 t full load

Dimensions: Length overall / water x beam x draught
 615.89 ft / 614.00 ft x 62.00 ft x 22.00 ft (normal load)
 187.72 m / 187.15 m x 18.90 m  x 6.71 m

Armament:
      8 - 9.20" / 234 mm guns (4x2 guns), 389.34lbs / 176.60kg shells, 1916 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 2 raised mounts - superfiring
      8 - 4.70" / 119 mm guns in single mounts, 51.91lbs / 23.55kg shells, 1916 Model
   Quick firing guns in deck mounts with hoists
   on side, all amidships
      2 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1916 Model
   Anti-aircraft guns in deck mounts with hoists
   on side, evenly spread
      12 - 1.57" / 40.0 mm guns (3x4 guns), 2.00lbs / 0.91kg shells, 1916 Model
   Anti-aircraft guns in deck mounts 
   on side ends, majority aft
 Weight of broadside 3,618 lbs / 1,641 kg
 Shells per gun, main battery: 120

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 4.00" / 102 mm 545.00 ft / 166.12 m 16.00 ft / 4.88 m
 Ends: Unarmoured
   Main Belt covers 137 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.00" / 25 mm 545.00 ft / 166.12 m 21.00 ft / 6.40 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 4.00" / 102 mm 3.00" / 76 mm  4.00" / 102 mm
 2nd: 2.00" / 51 mm       -   2.00" / 51 mm
 4th: 1.00" / 25 mm       -         -

   - Armour deck: 2.00" / 51 mm, Conning tower: 4.00" / 102 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 96,834 shp / 72,238 Kw = 31.00 kts
 Range 4,800nm at 15.00 kts
 Bunker at max displacement = 1,838 tons

Complement:
 662 - 861

Cost:
 £2.192 million / $8.768 million

Distribution of weights at normal displacement:
 Armament: 452 tons, 3.1 %
 Armour: 3,472 tons, 23.9 %
    - Belts: 1,393 tons, 9.6 %
    - Torpedo bulkhead: 423 tons, 2.9 %
    - Armament: 566 tons, 3.9 %
    - Armour Deck: 1,038 tons, 7.1 %
    - Conning Tower: 51 tons, 0.4 %
 Machinery: 3,608 tons, 24.8 %
 Hull, fittings & equipment: 5,457 tons, 37.5 %
 Fuel, ammunition & stores: 1,561 tons, 10.7 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   15,698 lbs / 7,121 Kg = 40.3 x 9.2 " / 234 mm shells or 2.0 torpedoes
 Stability (Unstable if below 1.00): 1.14
 Metacentric height 3.1 ft / 0.9 m
 Roll period: 14.8 seconds
 Steadiness - As gun platform (Average = 50 %): 53 %
   - Recoil effect (Restricted arc if above 1.00): 0.87
 Seaboat quality  (Average = 1.00): 1.06

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.608
 Length to Beam Ratio: 9.90 : 1
 'Natural speed' for length: 24.78 kts
 Power going to wave formation at top speed: 57 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 4.00 degrees
 Stern overhang: -2.00 ft / -0.61 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  27.00 ft / 8.23 m
    - Forecastle (20 %): 24.00 ft / 7.32 m
    - Mid (67 %):  24.00 ft / 7.32 m (16.00 ft / 4.88 m aft of break)
    - Quarterdeck (15 %): 16.00 ft / 4.88 m
    - Stern:  16.00 ft / 4.88 m
    - Average freeboard: 21.60 ft / 6.58 m
 Ship tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 153.9 %
  - Above water (accommodation/working, high = better): 175.8 %
 Waterplane Area: 28,053 Square feet or 2,606 Square metres
 Displacement factor (Displacement / loading): 102 %
 Structure weight / hull surface area: 120 lbs/sq ft or 586 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.97
  - Longitudinal: 1.32
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

A 1914 8-in gunned heavy cruiser

I thought an 8-in gunned heavy cruiser for 1914 might be an interesting design to try. The main difficulty is that I don't see the British building a cruiser with 8in guns in 1914. Aside from that, this seems viable. The armament is 8-8in BLR, 4-4.7in QF guns with shields, 2-3in AA guns, and 4-21in TT in deck mounts. The armour basis is 4in with a 2in deck. The maximum speed is 30 knots with a 15 knot cruising speed for a range of 4,800 miles. Of course, I used oil-fired boilers. This is the Sprinsharp report:

GB/CA/1914, Great Britain Cruiser laid down 1914

Displacement:
 10,487 t light; 10,852 t standard; 11,750 t normal; 12,469 t full load

Dimensions: Length overall / water x beam x draught
 546.42 ft / 545.00 ft x 72.00 ft x 21.00 ft (normal load)
 166.55 m / 166.12 m x 21.95 m  x 6.40 m

Armament:
      8 - 8.00" / 203 mm guns (4x2 guns), 256.00lbs / 116.12kg shells, 1914 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 2 raised mounts - superfiring
      4 - 4.70" / 119 mm guns in single mounts, 50.00lbs / 22.68kg shells, 1914 Model
   Quick firing guns in deck mounts with hoists
   on side, evenly spread
      2 - 3.00" / 76.2 mm guns in single mounts, 13.00lbs / 5.90kg shells, 1914 Model
   Anti-aircraft guns in deck mounts with hoists
   on side, evenly spread
 Weight of broadside 2,274 lbs / 1,031 kg
 Shells per gun, main battery: 100
 4 - 21.0" / 533.4 mm above water torpedoes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 4.00" / 102 mm 440.00 ft / 134.11 m 16.00 ft / 4.88 m
 Ends: Unarmoured
   Main Belt covers 124 % of normal length

   - Torpedo Bulkhead:
  1.00" / 25 mm 440.00 ft / 134.11 m 20.00 ft / 6.10 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 4.00" / 102 mm 3.00" / 76 mm  4.00" / 102 mm
 2nd: 2.00" / 51 mm       -   2.00" / 51 mm

   - Armour deck: 2.00" / 51 mm, Conning tower: 4.00" / 102 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 65,366 shp / 48,763 Kw = 30.00 kts
 Range 4,800nm at 15.00 kts
 Bunker at max displacement = 1,617 tons

Complement:
 563 - 733

Cost:
 £1.221 million / $4.883 million

Distribution of weights at normal displacement:
 Armament: 285 tons, 2.4 %
 Armour: 2,989 tons, 25.4 %
    - Belts: 1,152 tons, 9.8 %
    - Torpedo bulkhead: 326 tons, 2.8 %
    - Armament: 462 tons, 3.9 %
    - Armour Deck: 1,005 tons, 8.6 %
    - Conning Tower: 45 tons, 0.4 %
 Machinery: 2,518 tons, 21.4 %
 Hull, fittings & equipment: 4,695 tons, 40.0 %
 Fuel, ammunition & stores: 1,263 tons, 10.7 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   17,885 lbs / 8,112 Kg = 69.9 x 8.0 " / 203 mm shells or 2.8 torpedoes
 Stability (Unstable if below 1.00): 1.22
 Metacentric height 4.4 ft / 1.3 m
 Roll period: 14.4 seconds
 Steadiness - As gun platform (Average = 50 %): 55 %
   - Recoil effect (Restricted arc if above 1.00): 0.35
 Seaboat quality  (Average = 1.00): 1.10

Hull form characteristics:
 Hull has rise forward of midbreak
   and transom stern
 Block coefficient: 0.499
 Length to Beam Ratio: 7.57 : 1
 'Natural speed' for length: 27.27 kts
 Power going to wave formation at top speed: 59 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 3.00 degrees
 Stern overhang: -2.00 ft / -0.61 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  27.00 ft / 8.23 m
    - Forecastle (20 %): 24.00 ft / 7.32 m
    - Mid (67 %):  24.00 ft / 7.32 m (16.00 ft / 4.88 m aft of break)
    - Quarterdeck (15 %): 16.00 ft / 4.88 m
    - Stern:  16.00 ft / 4.88 m
    - Average freeboard: 21.60 ft / 6.58 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 122.2 %
  - Above water (accommodation/working, high = better): 186.1 %
 Waterplane Area: 27,165 Square feet or 2,524 Square metres
 Displacement factor (Displacement / loading): 114 %
 Structure weight / hull surface area: 117 lbs/sq ft or 572 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.94
  - Longitudinal: 1.73
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

I went overboard, tonight with the GB/CB/1941

I designed a mammoth, very fast battlecruiser for the British navy, tonight, that works well. The draft is an acceptable 35ft. This is something of a departure from the series that I have been designing, in that the hull is flush-decked and the ship has three triple turrets. The ship has the largest caliber guns allowed by Springsharp: 21in (I think). The ship is really a fast battleship, but given the high speed, I wanted to call the design a battlecruiser. The normal displacement is 160,000 tons. I went ahead and specified the 15,000nm range at 18 knots, so the design is suitable for Pacific warfare. The cost is outrageous, but the capability is so great that I don't mind. One of these ships could run to ground almost any other ship on the seas. Smaller ships could possibly outrun the ship in calm seas for a short distance, but in any sort of a seaway at all, this design would be faster, over a greater distance. This is the Springsharp report:

GB/CB/1941, Great Britain Battlecruiser laid down 1941

Displacement:
 140,234 t light; 145,356 t standard; 160,000 t normal; 171,715 t full load

Dimensions: Length overall / water x beam x draught
 1,255.15 ft / 1,250.00 ft x 150.00 ft x 35.00 ft (normal load)
 382.57 m / 381.00 m x 45.72 m  x 10.67 m

Armament:
      9 - 21.00" / 533 mm guns (3x3 guns), 4,630.50lbs / 2,100.36kg shells, 1941 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, majority forward, 1 raised mount - superfiring
      24 - 4.50" / 114 mm guns (10 mounts), 45.56lbs / 20.67kg shells, 1941 Model
   Dual purpose guns in turrets (on barbettes)
   on side, evenly spread, 10 raised mounts
      72 - 1.57" / 40.0 mm guns (18x4 guns), 1.95lbs / 0.89kg shells, 1941 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread, 8 raised mounts
 Weight of broadside 42,909 lbs / 19,463 kg
 Shells per gun, main battery: 80

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 17.0" / 432 mm 840.00 ft / 256.03 m 8.00 ft / 2.44 m
 Ends: Unarmoured
 Upper: 13.0" / 330 mm 840.00 ft / 256.03 m 8.00 ft / 2.44 m
   Main Belt covers 103 % of normal length

   - Torpedo Bulkhead:
  8.00" / 203 mm 840.00 ft / 256.03 m 34.00 ft / 10.36 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 17.0" / 432 mm 13.0" / 330 mm  17.0" / 432 mm
 2nd: 4.00" / 102 mm 4.00" / 102 mm  4.00" / 102 mm
 3rd: 1.00" / 25 mm       -         -

   - Armour deck: 9.00" / 229 mm, Conning tower: 12.00" / 305 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 8 shafts, 542,974 shp / 405,058 Kw = 35.00 kts
 Range 15,000nm at 18.00 kts
 Bunker at max displacement = 26,360 tons

Complement:
 3,999 - 5,200

Cost:
 £70.612 million / $282.447 million

Distribution of weights at normal displacement:
 Armament: 5,364 tons, 3.4 %
 Armour: 56,734 tons, 35.5 %
    - Belts: 8,597 tons, 5.4 %
    - Torpedo bulkhead: 8,454 tons, 5.3 %
    - Armament: 9,080 tons, 5.7 %
    - Armour Deck: 29,841 tons, 18.7 %
    - Conning Tower: 762 tons, 0.5 %
 Machinery: 14,349 tons, 9.0 %
 Hull, fittings & equipment: 63,787 tons, 39.9 %
 Fuel, ammunition & stores: 19,766 tons, 12.4 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   346,389 lbs / 157,119 Kg = 74.8 x 21.0 " / 533 mm shells or 88.6 torpedoes
 Stability (Unstable if below 1.00): 1.26
 Metacentric height 14.0 ft / 4.3 m
 Roll period: 16.8 seconds
 Steadiness - As gun platform (Average = 50 %): 59 %
   - Recoil effect (Restricted arc if above 1.00): 0.48
 Seaboat quality  (Average = 1.00): 1.18

Hull form characteristics:
 Hull has a flush deck
   and transom stern
 Block coefficient: 0.853
 Length to Beam Ratio: 8.33 : 1
 'Natural speed' for length: 39.71 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: 2.00 ft / 0.61 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  45.00 ft / 13.72 m
    - Forecastle (20 %): 35.00 ft / 10.67 m
    - Mid (67 %):  35.00 ft / 10.67 m
    - Quarterdeck (15 %): 35.00 ft / 10.67 m
    - Stern:  35.00 ft / 10.67 m
    - Average freeboard: 35.80 ft / 10.91 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 63.3 %
  - Above water (accommodation/working, high = better): 298.8 %
 Waterplane Area: 179,226 Square feet or 16,651 Square metres
 Displacement factor (Displacement / loading): 125 %
 Structure weight / hull surface area: 284 lbs/sq ft or 1,387 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 1.14
  - Longitudinal: 0.95
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is excellent
 Room for accommodation and workspaces is excellent

Talk about an "edgy" design: the GB/CB/1931

Continuing the current string of designs a step further is a design that is very edgy, in the sense of pushing the limits or propriety. The GB/CB/1931 has 8-20in BLR, 20-4.5in DP, and 56-2pdr AA guns. The armour basis is 16in and the maximum speed is 33 knots. The deck is up to 8in thick and the torpedo bulkhead is 6in. The range is a rather modest 8,500 nm, but that is at 18 knots. If the cruising speed is reduced to 15 knots, then the range opens up to a respectable 12,500nm. This is the Springsharp report:

GB/CB/1931, Great Britain Battlecruiser laid down 1931

Displacement:
 81,144 t light; 84,436 t standard; 90,600 t normal; 95,532 t full load

Dimensions: Length overall / water x beam x draught
 977.59 ft / 975.00 ft x 128.00 ft x 35.00 ft (normal load)
 297.97 m / 297.18 m x 39.01 m  x 10.67 m

Armament:
      8 - 20.00" / 508 mm guns (4x2 guns), 4,000.00lbs / 1,814.37kg shells, 1931 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 2 raised mounts - superfiring
      20 - 4.50" / 114 mm guns (10x2 guns), 45.56lbs / 20.67kg shells, 1931 Model
   Dual purpose guns in turrets (on barbettes)
   on side, evenly spread, all raised mounts
      56 - 1.57" / 40.0 mm guns (14x4 guns), 2.00lbs / 0.91kg shells, 1931 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread, 8 raised mounts
 Weight of broadside 33,023 lbs / 14,979 kg
 Shells per gun, main battery: 80

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 16.0" / 406 mm 650.00 ft / 198.12 m 8.00 ft / 2.44 m
 Ends: Unarmoured
 Upper: 12.0" / 305 mm 650.00 ft / 198.12 m 8.00 ft / 2.44 m
   Main Belt covers 103 % of normal length

   - Torpedo Bulkhead:
  6.00" / 152 mm 650.00 ft / 198.12 m 32.00 ft / 9.75 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 16.0" / 406 mm 12.0" / 305 mm  16.0" / 406 mm
 2nd: 4.00" / 102 mm 4.00" / 102 mm  4.00" / 102 mm
 3rd: 1.00" / 25 mm       -         -

   - Armour deck: 8.00" / 203 mm, Conning tower: 12.00" / 305 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 6 shafts, 307,571 shp / 229,448 Kw = 33.00 kts
 Range 8,500nm at 18.00 kts
 Bunker at max displacement = 11,096 tons

Complement:
 2,610 - 3,394

Cost:
 £33.141 million / $132.565 million

Distribution of weights at normal displacement:
 Armament: 4,128 tons, 4.6 %
 Armour: 34,489 tons, 38.1 %
    - Belts: 6,257 tons, 6.9 %
    - Torpedo bulkhead: 4,618 tons, 5.1 %
    - Armament: 7,266 tons, 8.0 %
    - Armour Deck: 15,827 tons, 17.5 %
    - Conning Tower: 522 tons, 0.6 %
 Machinery: 9,198 tons, 10.2 %
 Hull, fittings & equipment: 33,329 tons, 36.8 %
 Fuel, ammunition & stores: 9,456 tons, 10.4 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   140,813 lbs / 63,872 Kg = 35.2 x 20.0 " / 508 mm shells or 26.1 torpedoes
 Stability (Unstable if below 1.00): 1.13
 Metacentric height 9.2 ft / 2.8 m
 Roll period: 17.7 seconds
 Steadiness - As gun platform (Average = 50 %): 51 %
   - Recoil effect (Restricted arc if above 1.00): 0.65
 Seaboat quality  (Average = 1.00): 1.01

Hull form characteristics:
 Hull has rise forward of midbreak
   and transom stern
 Block coefficient: 0.726
 Length to Beam Ratio: 7.62 : 1
 'Natural speed' for length: 35.61 kts
 Power going to wave formation at top speed: 55 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 4.00 degrees
 Stern overhang: -2.00 ft / -0.61 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  37.00 ft / 11.28 m
    - Forecastle (20 %): 31.00 ft / 9.45 m
    - Mid (67 %):  31.00 ft / 9.45 m (23.00 ft / 7.01 m aft of break)
    - Quarterdeck (15 %): 23.00 ft / 7.01 m
    - Stern:  23.00 ft / 7.01 m
    - Average freeboard: 28.84 ft / 8.79 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 79.7 %
  - Above water (accommodation/working, high = better): 224.6 %
 Waterplane Area: 106,938 Square feet or 9,935 Square metres
 Displacement factor (Displacement / loading): 105 %
 Structure weight / hull surface area: 239 lbs/sq ft or 1,169 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.99
  - Longitudinal: 1.06
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is excellent
 Room for accommodation and workspaces is excellent

Is this really feasible? the GB/CB/1927

I had the idea, last night, that the next step would be to have an 18in-gunned battlecruiser in the same design series as the rest of the recent designs. This seems too good to be true, to me. The displacement is not that great, given the armament and speed (32 knots). True, I am not trying for the sort of range that American ships in the Pacific war had, where we would want a 15,000nm range. This is a 32-knot ship with 8-18in BLR, 16-6in QF, 6-4.7in AA, and 40-2pdr AA guns. The armour basis is a substantial 15in with a 7in deck and 5in torpedo bulkhead. The ship has a long forecastle and soft ends. The lower belt is thicker than the upper belt. I retained a thick CT, even though I don't really believe that it is needed. Everyone still had them at this date, so this design does, as well. This is the Springsharp report:

GB/CB/1927, Great Britain Battlecruiser laid down 1927

Displacement:
 63,705 t light; 66,289 t standard; 71,800 t normal; 76,208 t full load

Dimensions: Length overall / water x beam x draught
 917.45 ft / 915.00 ft x 116.00 ft x 33.00 ft (normal load)
 279.64 m / 278.89 m x 35.36 m  x 10.06 m

Armament:
      8 - 18.00" / 457 mm guns (4x2 guns), 2,916.00lbs / 1,322.68kg shells, 1927 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 2 raised mounts - superfiring
      16 - 6.00" / 152 mm guns (8x2 guns), 108.00lbs / 48.99kg shells, 1927 Model
   Quick firing guns in turrets (on barbettes)
   on side, evenly spread, 4 raised mounts
      6 - 4.70" / 119 mm guns in single mounts, 51.91lbs / 23.55kg shells, 1927 Model
   Anti-aircraft guns in deck mounts with hoists
   on side, evenly spread, 2 raised mounts
      40 - 1.57" / 40.0 mm guns (10x4 guns), 1.95lbs / 0.89kg shells, 1927 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread, 6 raised mounts
 Weight of broadside 25,446 lbs / 11,542 kg
 Shells per gun, main battery: 80

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 15.0" / 381 mm 600.00 ft / 182.88 m 8.00 ft / 2.44 m
 Ends: Unarmoured
 Upper: 10.0" / 254 mm 600.00 ft / 182.88 m 8.00 ft / 2.44 m
   Main Belt covers 101 % of normal length

   - Torpedo Bulkhead:
  5.00" / 127 mm 600.00 ft / 182.88 m 32.00 ft / 9.75 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 15.0" / 381 mm 11.0" / 279 mm  15.0" / 381 mm
 2nd: 4.00" / 102 mm 4.00" / 102 mm  4.00" / 102 mm
 4th: 1.00" / 25 mm       -         -

   - Armour deck: 7.00" / 178 mm, Conning tower: 15.00" / 381 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 239,713 shp / 178,826 Kw = 32.00 kts
 Range 8,500nm at 18.00 kts
 Bunker at max displacement = 9,919 tons

Complement:
 2,192 - 2,851

Cost:
 £21.676 million / $86.702 million

Distribution of weights at normal displacement:
 Armament: 3,181 tons, 4.4 %
 Armour: 26,785 tons, 37.3 %
    - Belts: 5,151 tons, 7.2 %
    - Torpedo bulkhead: 3,552 tons, 4.9 %
    - Armament: 5,836 tons, 8.1 %
    - Armour Deck: 11,688 tons, 16.3 %
    - Conning Tower: 558 tons, 0.8 %
 Machinery: 7,567 tons, 10.5 %
 Hull, fittings & equipment: 26,172 tons, 36.5 %
 Fuel, ammunition & stores: 8,095 tons, 11.3 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   110,280 lbs / 50,022 Kg = 37.8 x 18.0 " / 457 mm shells or 19.0 torpedoes
 Stability (Unstable if below 1.00): 1.12
 Metacentric height 7.8 ft / 2.4 m
 Roll period: 17.5 seconds
 Steadiness - As gun platform (Average = 50 %): 51 %
   - Recoil effect (Restricted arc if above 1.00): 0.68
 Seaboat quality  (Average = 1.00): 1.03

Hull form characteristics:
 Hull has rise forward of midbreak
   and transom stern
 Block coefficient: 0.717
 Length to Beam Ratio: 7.89 : 1
 'Natural speed' for length: 34.43 kts
 Power going to wave formation at top speed: 54 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 4.00 degrees
 Stern overhang: -2.00 ft / -0.61 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  35.00 ft / 10.67 m
    - Forecastle (20 %): 29.00 ft / 8.84 m
    - Mid (67 %):  29.00 ft / 8.84 m (21.00 ft / 6.40 m aft of break)
    - Quarterdeck (15 %): 21.00 ft / 6.40 m
    - Stern:  21.00 ft / 6.40 m
    - Average freeboard: 26.84 ft / 8.18 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 81.7 %
  - Above water (accommodation/working, high = better): 210.1 %
 Waterplane Area: 90,257 Square feet or 8,385 Square metres
 Displacement factor (Displacement / loading): 107 %
 Structure weight / hull surface area: 220 lbs/sq ft or 1,073 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 1.00
  - Longitudinal: 1.05
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is excellent
 Room for accommodation and workspaces is excellent

Another 1921 battlecruiser

I thought that I would extend my battlecruiser series to 1921 with a ship with 8-16.5in BLR, 16-6in QF, 6-4.7in AA, and 32-2pdr AA guns. The armour basis is a substantial 14in with a 5in deck. The speed of 32 knots has ballooned the displacement, but I felt that the ship should do better than the 31 knots of the preceding design. The combination of strength and seakeeping through a greater freeboard, along with the 32 knot speed is behind the great displacement for the rather small dimensions, although it is primarily the speed. I thought that for a 1921 design, a transom stern was appropriate, and it reduces the power requirement, and helps to keep the displacement as low as it is. This is the Springsharp report:

GB/CB/1921, Great Britain Battlecruiser laid down 1921

Displacement:
    49,896 t light; 51,920 t standard; 55,700 t normal; 58,724 t full load

Dimensions: Length overall / water x beam x draught
    867.38 ft / 865.00 ft x 106.00 ft x 32.00 ft (normal load)
    264.38 m / 263.65 m x 32.31 m  x 9.75 m

Armament:
      8 - 16.50" / 419 mm guns (4x2 guns), 2,246.06lbs / 1,018.80kg shells, 1921 Model
      Breech loading guns in turrets (on barbettes)
      on centreline ends, evenly spread, 2 raised mounts - superfiring
      16 - 6.00" / 152 mm guns (8x2 guns), 108.00lbs / 48.99kg shells, 1921 Model
      Quick firing guns in turrets (on barbettes)
      on side, evenly spread, 4 raised mounts
      6 - 4.70" / 119 mm guns in single mounts, 51.91lbs / 23.55kg shells, 1921 Model
      Anti-aircraft guns in deck mounts
      on side, evenly spread, 2 raised mounts
      32 - 1.57" / 40.0 mm guns (8x4 guns), 1.95lbs / 0.89kg shells, 1921 Model
      Anti-aircraft guns in deck mounts
      on side, evenly spread
    Weight of broadside 20,070 lbs / 9,104 kg
    Shells per gun, main battery: 80
    4 - 21.0" / 533.4 mm submerged torpedo tubes

Armour:
   - Belts:        Width (max)    Length (avg)        Height (avg)
    Main:    14.0" / 356 mm    570.00 ft / 173.74 m    8.00 ft / 2.44 m
    Ends:    Unarmoured
    Upper:    10.0" / 254 mm    570.00 ft / 173.74 m    8.00 ft / 2.44 m
      Main Belt covers 101 % of normal length

   - Torpedo Bulkhead:
        4.00" / 102 mm    570.00 ft / 173.74 m    31.00 ft / 9.45 m

   - Gun armour:    Face (max)    Other gunhouse (avg)    Barbette/hoist (max)
    Main:    14.0" / 356 mm    10.0" / 254 mm        14.0" / 356 mm
    2nd:    4.00" / 102 mm    4.00" / 102 mm        4.00" / 102 mm

   - Armour deck: 5.00" / 127 mm, Conning tower: 14.00" / 356 mm

Machinery:
    Oil fired boilers, steam turbines,
    Geared drive, 4 shafts, 203,003 shp / 151,440 Kw = 32.00 kts
    Range 6,400nm at 18.00 kts
    Bunker at max displacement = 6,804 tons

Complement:
    1,812 - 2,356

Cost:
    £12.301 million / $49.203 million

Distribution of weights at normal displacement:
    Armament: 2,509 tons, 4.5 %
    Armour: 19,462 tons, 34.9 %
       - Belts: 4,666 tons, 8.4 %
       - Torpedo bulkhead: 2,615 tons, 4.7 %
       - Armament: 4,871 tons, 8.7 %
       - Armour Deck: 6,870 tons, 12.3 %
       - Conning Tower: 440 tons, 0.8 %
    Machinery: 6,990 tons, 12.6 %
    Hull, fittings & equipment: 20,935 tons, 37.6 %
    Fuel, ammunition & stores: 5,804 tons, 10.4 %
    Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
    Survivability (Non-critical penetrating hits needed to sink ship):
      75,345 lbs / 34,176 Kg = 33.5 x 16.5 " / 419 mm shells or 11.3 torpedoes
    Stability (Unstable if below 1.00): 1.08
    Metacentric height 6.3 ft / 1.9 m
    Roll period: 17.7 seconds
    Steadiness    - As gun platform (Average = 50 %): 51 %
            - Recoil effect (Restricted arc if above 1.00): 0.77
    Seaboat quality  (Average = 1.00): 1.03

Hull form characteristics:
    Hull has rise forward of midbreak
      and transom stern
    Block coefficient: 0.664
    Length to Beam Ratio: 8.16 : 1
    'Natural speed' for length: 33.54 kts
    Power going to wave formation at top speed: 54 %
    Trim (Max stability = 0, Max steadiness = 100): 50
    Bow angle (Positive = bow angles forward): 4.00 degrees
    Stern overhang: -2.00 ft / -0.61 m
    Freeboard (% = measuring location as a percentage of overall length):
       - Stem:        34.00 ft / 10.36 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:    25.84 ft / 7.88 m

Ship space, strength and comments:
    Space    - Hull below water (magazines/engines, low = better): 93.6 %
        - Above water (accommodation/working, high = better): 201.3 %
    Waterplane Area: 74,274 Square feet or 6,900 Square metres
    Displacement factor (Displacement / loading): 104 %
    Structure weight / hull surface area: 207 lbs/sq ft or 1,009 Kg/sq metre
    Hull strength (Relative):
        - Cross-sectional: 0.99
        - Longitudinal: 1.08
        - Overall: 1.00
    Hull space for machinery, storage, compartmentation is adequate
    Room for accommodation and workspaces is excellent

The well-protected GB/CB/1918 with 16in guns

Keeping with slightly reduced dimensions with a good armament and protection, this is a GB/CB/1918 design. The Standard Displacement is somewhat more than the Hood, but the other characteristics are so much better than the Hood as to make that size investment well worth the cost. The armament is a very 1918-ish 8-16in BLR, 16-5.5in QF, 6-4.7in AA, and 32-2pdr AA guns. I retained the 4-21in submerged TT, for better or worse. The armour basis is 13in with a 4in deck and 3in torpedo bulkhead. This is the Springsharp report:

GB/CB/1918, Great Britain Battlecruiser laid down 1918

Displacement:
 42,222 t light; 43,984 t standard; 47,400 t normal; 50,133 t full load

Dimensions: Length overall / water x beam x draught
 845.00 ft / 845.00 ft x 102.00 ft x 31.00 ft (normal load)
 257.56 m / 257.56 m x 31.09 m  x 9.45 m

Armament:
      8 - 16.00" / 406 mm guns (4x2 guns), 2,048.00lbs / 928.96kg shells, 1918 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 2 raised mounts - superfiring
      16 - 5.50" / 140 mm guns in single mounts, 83.19lbs / 37.73kg shells, 1918 Model
   Quick firing guns in deck mounts with hoists
   on side, evenly spread, 8 raised mounts
      4 - 4.70" / 119 mm guns in single mounts, 51.91lbs / 23.55kg shells, 1918 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread, 2 raised mounts
      32 - 1.57" / 40.0 mm guns (4x8 guns), 2.00lbs / 0.91kg shells, 1918 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread
 Weight of broadside 17,987 lbs / 8,159 kg
 Shells per gun, main battery: 80
 4 - 21.0" / 533.4 mm submerged torpedo tubes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 13.0" / 330 mm 570.00 ft / 173.74 m 8.00 ft / 2.44 m
 Ends: Unarmoured
 Upper: 10.0" / 254 mm 570.00 ft / 173.74 m 8.00 ft / 2.44 m
   Main Belt covers 104 % of normal length

   - Torpedo Bulkhead:
  3.00" / 76 mm 570.00 ft / 173.74 m 30.00 ft / 9.14 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 13.0" / 330 mm 9.00" / 229 mm  13.0" / 330 mm
 2nd: 4.00" / 102 mm 4.00" / 102 mm  4.00" / 102 mm

   - Armour deck: 4.00" / 102 mm, Conning tower: 13.00" / 330 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 183,046 shp / 136,552 Kw = 31.00 kts
 Range 5,600nm at 18.00 kts
 Bunker at max displacement = 6,149 tons

Complement:
 1,606 - 2,088

Cost:
 £8.581 million / $34.325 million

Distribution of weights at normal displacement:
 Armament: 2,248 tons, 4.7 %
 Armour: 15,190 tons, 32.0 %
    - Belts: 4,433 tons, 9.4 %
    - Torpedo bulkhead: 1,898 tons, 4.0 %
    - Armament: 3,736 tons, 7.9 %
    - Armour Deck: 4,757 tons, 10.0 %
    - Conning Tower: 367 tons, 0.8 %
 Machinery: 6,603 tons, 13.9 %
 Hull, fittings & equipment: 18,180 tons, 38.4 %
 Fuel, ammunition & stores: 5,178 tons, 10.9 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   57,931 lbs / 26,277 Kg = 28.3 x 16.0 " / 406 mm shells or 8.1 torpedoes
 Stability (Unstable if below 1.00): 1.10
 Metacentric height 6.1 ft / 1.9 m
 Roll period: 17.3 seconds
 Steadiness - As gun platform (Average = 50 %): 54 %
   - Recoil effect (Restricted arc if above 1.00): 0.75
 Seaboat quality  (Average = 1.00): 1.07

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.621
 Length to Beam Ratio: 8.28 : 1
 'Natural speed' for length: 29.07 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 %): 26.00 ft / 7.92 m
    - Mid (67 %):  26.00 ft / 7.92 m (18.00 ft / 5.49 m aft of break)
    - Quarterdeck (15 %): 18.00 ft / 5.49 m
    - Stern:  18.00 ft / 5.49 m
    - Average freeboard: 23.84 ft / 7.27 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 102.4 %
  - Above water (accommodation/working, high = better): 181.3 %
 Waterplane Area: 64,278 Square feet or 5,972 Square metres
 Displacement factor (Displacement / loading): 102 %
 Structure weight / hull surface area: 201 lbs/sq ft or 981 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 1.00
  - Longitudinal: 1.03
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is adequate
 Room for accommodation and workspaces is excellent

A compact analog to the Hood

The next obvious step was a 15in-gun battlecruiser with 12in armour. I continued the practice of reducing dimensions to obtain greater strength. I had to increase the beam due to stability and recoil issues. I kept the soft ends and a thicker lower belt and thinner upper belt. This is sort of a more heavily armed and armoured Renown. I also settled for a lower speed to keep the size reasonable. The secondary armament is transitional, with twin 4in QF mounts. This is the Springsharp report:

GB/CB/1915, Great Britain Battlecruiser laid down 1915

Displacement:
 32,975 t light; 34,446 t standard; 37,750 t normal; 40,393 t full load

Dimensions: Length overall / water x beam x draught
 780.00 ft / 780.00 ft x 95.00 ft x 29.00 ft (normal load)
 237.74 m / 237.74 m x 28.96 m  x 8.84 m

Armament:
      8 - 15.00" / 381 mm guns (4x2 guns), 1,920.00lbs / 870.90kg shells, 1915 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 2 raised mounts - superfiring
      16 - 4.00" / 102 mm guns (8x2 guns), 32.00lbs / 14.51kg shells, 1915 Model
   Quick firing guns in deck mounts with hoists
   on side, evenly spread, 6 raised mounts
      2 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1915 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread, all raised mounts
      16 - 1.57" / 40.0 mm guns (4x4 guns), 2.00lbs / 0.91kg shells, 1915 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread
 Weight of broadside 15,968 lbs / 7,243 kg
 Shells per gun, main battery: 80
 4 - 21.0" / 533.4 mm submerged torpedo tubes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 12.0" / 305 mm 570.00 ft / 173.74 m 8.00 ft / 2.44 m
 Ends: Unarmoured
 Upper: 8.00" / 203 mm 570.00 ft / 173.74 m 8.00 ft / 2.44 m
   Main Belt covers 112 % of normal length

   - Torpedo Bulkhead:
  2.00" / 51 mm 570.00 ft / 173.74 m 28.00 ft / 8.53 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 12.0" / 305 mm 9.00" / 229 mm  12.0" / 305 mm
 2nd: 4.00" / 102 mm 4.00" / 102 mm  4.00" / 102 mm

   - Armour deck: 3.00" / 76 mm, Conning tower: 12.00" / 305 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 125,717 shp / 93,785 Kw = 29.00 kts
 Range 5,600nm at 18.00 kts
 Bunker at max displacement = 5,946 tons

Complement:
 1,353 - 1,760

Cost:
 £4.803 million / $19.212 million

Distribution of weights at normal displacement:
 Armament: 1,763 tons, 4.7 %
 Armour: 11,398 tons, 30.2 %
    - Belts: 3,807 tons, 10.1 %
    - Torpedo bulkhead: 1,181 tons, 3.1 %
    - Armament: 3,070 tons, 8.1 %
    - Armour Deck: 3,050 tons, 8.1 %
    - Conning Tower: 291 tons, 0.8 %
 Machinery: 4,762 tons, 12.6 %
 Hull, fittings & equipment: 15,051 tons, 39.9 %
 Fuel, ammunition & stores: 4,775 tons, 12.7 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   49,031 lbs / 22,240 Kg = 29.1 x 15.0 " / 381 mm shells or 6.9 torpedoes
 Stability (Unstable if below 1.00): 1.08
 Metacentric height 5.4 ft / 1.6 m
 Roll period: 17.2 seconds
 Steadiness - As gun platform (Average = 50 %): 58 %
   - Recoil effect (Restricted arc if above 1.00): 0.90
 Seaboat quality  (Average = 1.00): 1.16

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.615
 Length to Beam Ratio: 8.21 : 1
 'Natural speed' for length: 27.93 kts
 Power going to wave formation at top speed: 50 %
 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:  31.00 ft / 9.45 m
    - Forecastle (20 %): 25.00 ft / 7.62 m
    - Mid (67 %):  25.00 ft / 7.62 m (17.00 ft / 5.18 m aft of break)
    - Quarterdeck (15 %): 17.00 ft / 5.18 m
    - Stern:  17.00 ft / 5.18 m
    - Average freeboard: 22.84 ft / 6.96 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 98.8 %
  - Above water (accommodation/working, high = better): 176.3 %
 Waterplane Area: 54,951 Square feet or 5,105 Square metres
 Displacement factor (Displacement / loading): 108 %
 Structure weight / hull surface area: 193 lbs/sq ft or 943 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.99
  - Longitudinal: 1.13
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is adequate
 Room for accommodation and workspaces is excellent

The "Tiger" version of the more heavily protected battlecruisers

The natural thing is to have a 1911 British battlecruiser that is better protected. The design is Tiger-like, except for the soft ends. For better or worse, I am using reduced dimensions, as that increases the "composite strength" in Springsharp. I thought that this design needed to be 28 knots, at least, so that ballooned the displacement by 1,000 tons. This is the Springsharp report:

GB/CB/1911, Great Britain Battlecruiser laid down 1911

Displacement:
 26,702 t light; 27,843 t standard; 31,200 t normal; 33,886 t full load

Dimensions: Length overall / water x beam x draught
 690.00 ft / 690.00 ft x 89.00 ft x 29.00 ft (normal load)
 210.31 m / 210.31 m x 27.13 m  x 8.84 m

Armament:
      8 - 13.50" / 343 mm guns (4x2 guns), 1,230.19lbs / 558.00kg shells, 1911 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 2 raised mounts - superfiring
      14 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1911 Model
   Quick firing guns in casemate mounts 
   on side, evenly spread, 4 raised mounts
      2 - 3.00" / 76.2 mm guns in single mounts, 13.50lbs / 6.12kg shells, 1911 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread, all raised mounts
 Weight of broadside 11,381 lbs / 5,162 kg
 Shells per gun, main battery: 80
 4 - 21.0" / 533.4 mm submerged torpedo tubes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 12.0" / 305 mm 460.00 ft / 140.21 m 8.00 ft / 2.44 m
 Ends: Unarmoured
 Upper: 8.00" / 203 mm 460.00 ft / 140.21 m 8.00 ft / 2.44 m
   Main Belt covers 103 % of normal length

   - Torpedo Bulkhead:
  2.00" / 51 mm 460.00 ft / 140.21 m 28.00 ft / 8.53 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 12.0" / 305 mm 9.00" / 229 mm  12.0" / 305 mm
 2nd: 4.00" / 102 mm 4.00" / 102 mm  4.00" / 102 mm

   - Armour deck: 3.00" / 76 mm, Conning tower: 12.00" / 305 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 102,012 shp / 76,101 Kw = 28.00 kts
 Range 5,400nm at 18.00 kts
 Bunker at max displacement = 6,042 tons

Complement:
 1,173 - 1,525

Cost:
 £2.709 million / $10.837 million

Distribution of weights at normal displacement:
 Armament: 1,423 tons, 4.6 %
 Armour: 9,634 tons, 30.9 %
    - Belts: 3,142 tons, 10.1 %
    - Torpedo bulkhead: 953 tons, 3.1 %
    - Armament: 2,759 tons, 8.8 %
    - Armour Deck: 2,524 tons, 8.1 %
    - Conning Tower: 256 tons, 0.8 %
 Machinery: 4,140 tons, 13.3 %
 Hull, fittings & equipment: 11,505 tons, 36.9 %
 Fuel, ammunition & stores: 4,498 tons, 14.4 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   39,656 lbs / 17,988 Kg = 32.2 x 13.5 " / 343 mm shells or 5.6 torpedoes
 Stability (Unstable if below 1.00): 1.07
 Metacentric height 4.8 ft / 1.5 m
 Roll period: 17.0 seconds
 Steadiness - As gun platform (Average = 50 %): 58 %
   - Recoil effect (Restricted arc if above 1.00): 0.79
 Seaboat quality  (Average = 1.00): 1.16

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.613
 Length to Beam Ratio: 7.75 : 1
 'Natural speed' for length: 26.27 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:  29.00 ft / 8.84 m
    - Forecastle (20 %): 25.00 ft / 7.62 m
    - Mid (67 %):  25.00 ft / 7.62 m (17.00 ft / 5.18 m aft of break)
    - Quarterdeck (15 %): 17.00 ft / 5.18 m
    - Stern:  17.00 ft / 5.18 m
    - Average freeboard: 22.68 ft / 6.91 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 102.5 %
  - Above water (accommodation/working, high = better): 168.2 %
 Waterplane Area: 45,470 Square feet or 4,224 Square metres
 Displacement factor (Displacement / loading): 107 %
 Structure weight / hull surface area: 174 lbs/sq ft or 848 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.97
  - Longitudinal: 1.33
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is adequate
 Room for accommodation and workspaces is excellent

A GB/CB/1909 battlecruiser with 11in armour

Perhaps using oil-fired boilers on a British capital ship in 1909 is "cheating", but having them allows for a very potent ship. This is a small-dimension battlecruiser with 8-13.5 guns with the superfiring guns aft. The lower belt, barbettes, and turret faces are 11in thick. The deck is 3in with a 2in torpedo bulkhead. This design is much more capable than the Lion class, but probably only is due to the oil-fired boilers. I also omit armour at the ends, as the unarmoured length is relatively small. This is the Springsharp report:

GB/CB/1909, Great Britain Battlecruiser laid down 1909

Displacement:
 24,493 t light; 25,541 t standard; 29,100 t normal; 31,947 t full load

Dimensions: Length overall / water x beam x draught
 670.00 ft / 670.00 ft x 87.00 ft x 28.00 ft (normal load)
 204.22 m / 204.22 m x 26.52 m  x 8.53 m

Armament:
      8 - 13.50" / 343 mm guns (4x2 guns), 1,230.19lbs / 558.00kg shells, 1909 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 1 raised mount aft - superfiring
      16 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1909 Model
   Quick firing guns in casemate mounts 
   on side, evenly spread, 6 raised mounts
 Weight of broadside 10,354 lbs / 4,696 kg
 Shells per gun, main battery: 80
 4 - 21.0" / 533.4 mm submerged torpedo tubes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 11.0" / 279 mm 450.00 ft / 137.16 m 8.00 ft / 2.44 m
 Ends: Unarmoured
 Upper: 8.00" / 203 mm 450.00 ft / 137.16 m 8.00 ft / 2.44 m
   Main Belt covers 103 % of normal length

   - Torpedo Bulkhead:
  2.00" / 51 mm 450.00 ft / 137.16 m 27.00 ft / 8.23 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 11.0" / 279 mm 8.00" / 203 mm  11.0" / 279 mm
 2nd: 4.00" / 102 mm 4.00" / 102 mm  4.00" / 102 mm

   - Armour deck: 3.00" / 76 mm, Conning tower: 11.00" / 279 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 86,024 shp / 64,174 Kw = 27.00 kts
 Range 5,400nm at 18.00 kts
 Bunker at max displacement = 6,406 tons

Complement:
 1,113 - 1,448

Cost:
 £2.492 million / $9.967 million

Distribution of weights at normal displacement:
 Armament: 1,294 tons, 4.4 %
 Armour: 8,832 tons, 30.3 %
    - Belts: 2,919 tons, 10.0 %
    - Torpedo bulkhead: 899 tons, 3.1 %
    - Armament: 2,370 tons, 8.1 %
    - Armour Deck: 2,420 tons, 8.3 %
    - Conning Tower: 224 tons, 0.8 %
 Machinery: 3,910 tons, 13.4 %
 Hull, fittings & equipment: 10,457 tons, 35.9 %
 Fuel, ammunition & stores: 4,607 tons, 15.8 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   38,281 lbs / 17,364 Kg = 31.1 x 13.5 " / 343 mm shells or 5.4 torpedoes
 Stability (Unstable if below 1.00): 1.12
 Metacentric height 5.0 ft / 1.5 m
 Roll period: 16.4 seconds
 Steadiness - As gun platform (Average = 50 %): 63 %
   - Recoil effect (Restricted arc if above 1.00): 0.75
 Seaboat quality  (Average = 1.00): 1.26

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.624
 Length to Beam Ratio: 7.70 : 1
 'Natural speed' for length: 25.88 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:  29.00 ft / 8.84 m
    - Forecastle (20 %): 25.00 ft / 7.62 m
    - Mid (67 %):  25.00 ft / 7.62 m (17.00 ft / 5.18 m aft of break)
    - Quarterdeck (15 %): 17.00 ft / 5.18 m
    - Stern:  17.00 ft / 5.18 m
    - Average freeboard: 22.68 ft / 6.91 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 102.9 %
  - Above water (accommodation/working, high = better): 170.0 %
 Waterplane Area: 43,597 Square feet or 4,050 Square metres
 Displacement factor (Displacement / loading): 108 %
 Structure weight / hull surface area: 165 lbs/sq ft or 804 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.97
  - Longitudinal: 1.36
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is adequate
 Room for accommodation and workspaces is excellent
 Good seaboat, rides out heavy weather easily

A 1908 British battlecruiser with better protection

When you look at just how bad the Indefatigable design was, especially compared to the Jane's Fighting Ships entry, you wonder why they couldn't have done better. I tried my hand at such a better design. I wanted the 9in belt and a 3in deck, in this case, along with a decent speed. My design relies on one turret being superfiring aft, and on oil-fired boilers, a big stretch. This is the Springsharp report:

GB/CB/1908, Great Britain Battlecruiser laid down 1908

Displacement:
 19,068 t light; 19,835 t standard; 21,550 t normal; 22,922 t full load

Dimensions: Length overall / water x beam x draught
 600.00 ft / 600.00 ft x 80.00 ft x 27.00 ft (normal load)
 182.88 m / 182.88 m x 24.38 m  x 8.23 m

Armament:
      8 - 12.00" / 305 mm guns (4x2 guns), 864.00lbs / 391.90kg shells, 1908 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 1 raised mount aft - superfiring
      16 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1908 Model
   Quick firing guns in casemate mounts 
   on side, evenly spread, 8 raised mounts
 Weight of broadside 7,424 lbs / 3,367 kg
 Shells per gun, main battery: 80
 4 - 18.0" / 457.2 mm submerged torpedo tubes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 9.00" / 229 mm 490.00 ft / 149.35 m 8.00 ft / 2.44 m
 Ends: Unarmoured
 Upper: 6.00" / 152 mm 490.00 ft / 149.35 m 8.00 ft / 2.44 m
   Main Belt covers 126 % of normal length

   - Torpedo Bulkhead:
  1.50" / 38 mm 490.00 ft / 149.35 m 26.00 ft / 7.92 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 9.00" / 229 mm 6.00" / 152 mm  9.00" / 229 mm
 2nd: 4.00" / 102 mm 4.00" / 102 mm  4.00" / 102 mm

   - Armour deck: 3.00" / 76 mm, Conning tower: 9.00" / 229 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 73,360 shp / 54,727 Kw = 27.00 kts
 Range 4,500nm at 15.00 kts
 Bunker at max displacement = 3,087 tons

Complement:
 889 - 1,156

Cost:
 £1.966 million / $7.862 million

Distribution of weights at normal displacement:
 Armament: 928 tons, 4.3 %
 Armour: 6,790 tons, 31.5 %
    - Belts: 2,416 tons, 11.2 %
    - Torpedo bulkhead: 707 tons, 3.3 %
    - Armament: 1,601 tons, 7.4 %
    - Armour Deck: 1,916 tons, 8.9 %
    - Conning Tower: 150 tons, 0.7 %
 Machinery: 3,705 tons, 17.2 %
 Hull, fittings & equipment: 7,645 tons, 35.5 %
 Fuel, ammunition & stores: 2,482 tons, 11.5 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   24,423 lbs / 11,078 Kg = 28.3 x 12.0 " / 305 mm shells or 3.5 torpedoes
 Stability (Unstable if below 1.00): 1.12
 Metacentric height 4.4 ft / 1.3 m
 Roll period: 16.0 seconds
 Steadiness - As gun platform (Average = 50 %): 57 %
   - Recoil effect (Restricted arc if above 1.00): 0.66
 Seaboat quality  (Average = 1.00): 1.14

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.582
 Length to Beam Ratio: 7.50 : 1
 'Natural speed' for length: 24.49 kts
 Power going to wave formation at top speed: 54 %
 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:  27.00 ft / 8.23 m
    - Forecastle (20 %): 23.00 ft / 7.01 m
    - Mid (67 %):  23.00 ft / 7.01 m (15.00 ft / 4.57 m aft of break)
    - Quarterdeck (15 %): 15.00 ft / 4.57 m
    - Stern:  15.00 ft / 4.57 m
    - Average freeboard: 20.68 ft / 6.30 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 120.9 %
  - Above water (accommodation/working, high = better): 153.7 %
 Waterplane Area: 34,519 Square feet or 3,207 Square metres
 Displacement factor (Displacement / loading): 100 %
 Structure weight / hull surface area: 149 lbs/sq ft or 728 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.96
  - Longitudinal: 1.46
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

Now, let us try well-protected battlecruisers

Now, let us see what might be done for a well-protected British battlecruiser for 1906, as an alternative to the Invincibles, but still a cruiser, not a fast battleship. This version is rather strange, as the dimensions are reduced to achieve adequate strength without ballooning the displacement unnecessarily. Part of the strangeness is that this version embraces the 25.5 knot speed, rather than 25 knots. The 25.5 knot speed was a feature of some design studies during the 1906-1908 period, and we are using that for this design. "Better protection" means a 9in belt. This design abandons the 16ft high thick belt for a thicker lower belt and a thinner upper belt, again to keep the displacement from undue increases. One of the two 12in gun turrets aft is superfiring. All turrets are on the centerline, with one amidships, although you would not necessarily know it from the Springsharp report:

GB/CB/1906, Great Britain Battlecruiser laid down 1906

Displacement:
 17,560 t light; 18,299 t standard; 20,150 t normal; 21,631 t full load

Dimensions: Length overall / water x beam x draught
 545.00 ft / 545.00 ft x 77.00 ft x 27.00 ft (normal load)
 166.12 m / 166.12 m x 23.47 m  x 8.23 m

Armament:
      8 - 12.00" / 305 mm guns (4x2 guns), 864.00lbs / 391.90kg shells, 1906 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 1 raised mount aft - superfiring
      16 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1906 Model
   Quick firing guns in casemate mounts 
   on side, evenly spread, 8 raised mounts
 Weight of broadside 7,424 lbs / 3,367 kg
 Shells per gun, main battery: 80
 4 - 18.0" / 457.2 mm submerged torpedo tubes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 9.00" / 229 mm 460.00 ft / 140.21 m 8.00 ft / 2.44 m
 Ends: Unarmoured
 Upper: 6.00" / 152 mm 460.00 ft / 140.21 m 8.00 ft / 2.44 m
   Main Belt covers 130 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.50" / 38 mm 460.00 ft / 140.21 m 26.00 ft / 7.92 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 9.00" / 229 mm 6.00" / 152 mm  9.00" / 229 mm
 2nd: 4.00" / 102 mm 4.00" / 102 mm  4.00" / 102 mm

   - Armour deck: 2.00" / 51 mm, Conning tower: 9.00" / 229 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 59,493 shp / 44,382 Kw = 25.50 kts
 Range 4,500nm at 15.00 kts
 Bunker at max displacement = 3,332 tons

Complement:
 845 - 1,099

Cost:
 £1.935 million / $7.740 million

Distribution of weights at normal displacement:
 Armament: 928 tons, 4.6 %
 Armour: 5,834 tons, 29.0 %
    - Belts: 2,266 tons, 11.2 %
    - Torpedo bulkhead: 664 tons, 3.3 %
    - Armament: 1,601 tons, 7.9 %
    - Armour Deck: 1,160 tons, 5.8 %
    - Conning Tower: 144 tons, 0.7 %
 Machinery: 3,863 tons, 19.2 %
 Hull, fittings & equipment: 6,935 tons, 34.4 %
 Fuel, ammunition & stores: 2,590 tons, 12.9 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   20,343 lbs / 9,227 Kg = 23.5 x 12.0 " / 305 mm shells or 2.8 torpedoes
 Stability (Unstable if below 1.00): 1.10
 Metacentric height 4.0 ft / 1.2 m
 Roll period: 16.1 seconds
 Steadiness - As gun platform (Average = 50 %): 55 %
   - Recoil effect (Restricted arc if above 1.00): 0.76
 Seaboat quality  (Average = 1.00): 1.11

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.622
 Length to Beam Ratio: 7.08 : 1
 'Natural speed' for length: 23.35 kts
 Power going to wave formation at top speed: 55 %
 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:  27.00 ft / 8.23 m
    - Forecastle (20 %): 23.00 ft / 7.01 m
    - Mid (67 %):  23.00 ft / 7.01 m (15.00 ft / 4.57 m aft of break)
    - Quarterdeck (15 %): 15.00 ft / 4.57 m
    - Stern:  15.00 ft / 4.57 m
    - Average freeboard: 20.68 ft / 6.30 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 134.9 %
  - Above water (accommodation/working, high = better): 146.8 %
 Waterplane Area: 31,340 Square feet or 2,912 Square metres
 Displacement factor (Displacement / loading): 96 %
 Structure weight / hull surface area: 148 lbs/sq ft or 722 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.95
  - Longitudinal: 1.65
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

The next step: a 1923 British fast battleship with 18in guns

Last night, I designed the ultimate ship in the series of British fast battleships from 1905 to 1923. This ship is very compact in dimensions but has a full form, to achieve adequate strength. The speed is a modest 28 knots (faster than the Yamatos) and the armament is 9-18in, 16-6in, 6-4.7in AA, and 36-2pdr AA guns. The armour basis is 15in. The deck is a thick 8in. The ship seems to be small for the capabilities, so I wonder if there is some flaw that I am not seeing. This is the Springsharp report:

GB/BB/1923, Great Britain Battleship laid down 1923

Displacement:
 58,640 t light; 61,238 t standard; 66,000 t normal; 69,810 t full load

Dimensions: Length overall / water x beam x draught
 827.24 ft / 825.00 ft x 112.00 ft x 35.00 ft (normal load)
 252.14 m / 251.46 m x 34.14 m  x 10.67 m

Armament:
      9 - 18.00" / 457 mm guns (3x3 guns), 2,916.00lbs / 1,322.68kg shells, 1923 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, majority aft, 1 raised mount aft - superfiring
      16 - 6.00" / 152 mm guns (8x2 guns), 108.00lbs / 48.99kg shells, 1923 Model
   Quick firing guns in turrets (on barbettes)
   on side, evenly spread, 4 raised mounts
      6 - 4.70" / 119 mm guns in single mounts, 51.91lbs / 23.55kg shells, 1923 Model
   Anti-aircraft guns in deck mounts with hoists
   on side ends, evenly spread
      36 - 1.57" / 40.0 mm guns (9x4 guns), 1.95lbs / 0.89kg shells, 1923 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread
 Weight of broadside 28,354 lbs / 12,861 kg
 Shells per gun, main battery: 80

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 15.0" / 381 mm 540.00 ft / 164.59 m 16.00 ft / 4.88 m
 Ends: Unarmoured
   Main Belt covers 101 % of normal length

   - Torpedo Bulkhead:
  5.00" / 127 mm 540.00 ft / 164.59 m 31.00 ft / 9.45 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 15.0" / 381 mm 11.0" / 279 mm  15.0" / 381 mm
 2nd: 6.00" / 152 mm 6.00" / 152 mm  6.00" / 152 mm

   - Armour deck: 8.00" / 203 mm, Conning tower: 15.00" / 381 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 159,663 shp / 119,108 Kw = 29.00 kts
 Range 7,500nm at 18.00 kts
 Bunker at max displacement = 8,572 tons

Complement:
 2,058 - 2,676

Cost:
 £16.805 million / $67.219 million

Distribution of weights at normal displacement:
 Armament: 3,544 tons, 5.4 %
 Armour: 26,397 tons, 40.0 %
    - Belts: 5,608 tons, 8.5 %
    - Torpedo bulkhead: 3,097 tons, 4.7 %
    - Armament: 5,569 tons, 8.4 %
    - Armour Deck: 11,596 tons, 17.6 %
    - Conning Tower: 528 tons, 0.8 %
 Machinery: 5,336 tons, 8.1 %
 Hull, fittings & equipment: 23,362 tons, 35.4 %
 Fuel, ammunition & stores: 7,360 tons, 11.2 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   93,522 lbs / 42,421 Kg = 32.1 x 18.0 " / 457 mm shells or 16.1 torpedoes
 Stability (Unstable if below 1.00): 1.09
 Metacentric height 7.0 ft / 2.1 m
 Roll period: 17.8 seconds
 Steadiness - As gun platform (Average = 50 %): 54 %
   - Recoil effect (Restricted arc if above 1.00): 0.79
 Seaboat quality  (Average = 1.00): 1.09

Hull form characteristics:
 Hull has a flush deck
   and transom stern
 Block coefficient: 0.714
 Length to Beam Ratio: 7.37 : 1
 'Natural speed' for length: 32.88 kts
 Power going to wave formation at top speed: 53 %
 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:  32.00 ft / 9.75 m
    - Forecastle (20 %): 24.00 ft / 7.32 m
    - Mid (67 %):  24.00 ft / 7.32 m
    - Quarterdeck (15 %): 24.00 ft / 7.32 m
    - Stern:  24.00 ft / 7.32 m
    - Average freeboard: 24.64 ft / 7.51 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 81.0 %
  - Above water (accommodation/working, high = better): 174.0 %
 Waterplane Area: 78,348 Square feet or 7,279 Square metres
 Displacement factor (Displacement / loading): 101 %
 Structure weight / hull surface area: 224 lbs/sq ft or 1,091 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.97
  - Longitudinal: 1.24
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is excellent
 Room for accommodation and workspaces is excellent

My current version of a 1919 British fast battleship

Continuing the current British fast battleship series is the 1919 version. The British considered 16.5in guns and I have adopted them. 16in guns were too small for that date, considering that larger guns were being actively developed. I had wanted 29 knots for this ship, but the size increase was greater than I wanted to have. I settled for a 28-knot ship with 9-16.5in BLR, 16-6in QF, 6-4.7in AA, and 36-2pdr AA guns. The armour basis is 14in. The deck is a respectable 6in. The torpedo bulkhead is a robust 4in. The hull is flush-decked and has a transom stern. This is the Springsharp report:

GB/BB/1919, Great Britain Battleship laid down 1919

Displacement:
 47,618 t light; 49,778 t standard; 54,250 t normal; 57,828 t full load

Dimensions: Length overall / water x beam x draught
 814.03 ft / 812.00 ft x 104.00 ft x 33.00 ft (normal load)
 248.12 m / 247.50 m x 31.70 m  x 10.06 m

Armament:
      9 - 16.50" / 419 mm guns (3x3 guns), 2,425.00lbs / 1,099.96kg shells, 1919 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, majority aft, 1 raised mount aft - superfiring
      16 - 6.00" / 152 mm guns (8x2 guns), 100.00lbs / 45.36kg shells, 1919 Model
   Quick firing guns in turrets (on barbettes)
   on side, evenly spread, 4 raised mounts
      6 - 4.70" / 119 mm guns in single mounts, 51.91lbs / 23.55kg shells, 1919 Model
   Anti-aircraft guns in deck mounts with hoists
   on side ends, evenly spread
      36 - 1.57" / 40.0 mm guns (9x4 guns), 2.00lbs / 0.91kg shells, 1919 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread
 Weight of broadside 23,808 lbs / 10,799 kg
 Shells per gun, main battery: 80

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 14.0" / 356 mm 540.00 ft / 164.59 m 16.00 ft / 4.88 m
 Ends: Unarmoured
   Main Belt covers 102 % of normal length

   - Torpedo Bulkhead:
  4.00" / 102 mm 540.00 ft / 164.59 m 31.00 ft / 9.45 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 14.0" / 356 mm 10.0" / 254 mm  14.0" / 356 mm
 2nd: 6.00" / 152 mm 6.00" / 152 mm  6.00" / 152 mm

   - Armour deck: 6.00" / 152 mm, Conning tower: 14.00" / 356 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 122,724 shp / 91,552 Kw = 28.00 kts
 Range 7,500nm at 18.00 kts
 Bunker at max displacement = 8,050 tons

Complement:
 1,776 - 2,310

Cost:
 £10.082 million / $40.327 million

Distribution of weights at normal displacement:
 Armament: 2,791 tons, 5.1 %
 Armour: 20,507 tons, 37.8 %
    - Belts: 5,177 tons, 9.5 %
    - Torpedo bulkhead: 2,478 tons, 4.6 %
    - Armament: 4,707 tons, 8.7 %
    - Armour Deck: 7,713 tons, 14.2 %
    - Conning Tower: 432 tons, 0.8 %
 Machinery: 4,358 tons, 8.0 %
 Hull, fittings & equipment: 19,962 tons, 36.8 %
 Fuel, ammunition & stores: 6,632 tons, 12.2 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   79,895 lbs / 36,240 Kg = 35.6 x 16.5 " / 419 mm shells or 13.4 torpedoes
 Stability (Unstable if below 1.00): 1.08
 Metacentric height 6.2 ft / 1.9 m
 Roll period: 17.6 seconds
 Steadiness - As gun platform (Average = 50 %): 60 %
   - Recoil effect (Restricted arc if above 1.00): 0.88
 Seaboat quality  (Average = 1.00): 1.19

Hull form characteristics:
 Hull has a flush deck
   and transom stern
 Block coefficient: 0.681
 Length to Beam Ratio: 7.81 : 1
 'Natural speed' for length: 32.56 kts
 Power going to wave formation at top speed: 50 %
 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:  29.00 ft / 8.84 m
    - Forecastle (20 %): 23.00 ft / 7.01 m
    - Mid (67 %):  23.00 ft / 7.01 m
    - Quarterdeck (15 %): 23.00 ft / 7.01 m
    - Stern:  23.00 ft / 7.01 m
    - Average freeboard: 23.48 ft / 7.16 m
 Ship tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 80.3 %
  - Above water (accommodation/working, high = better): 171.4 %
 Waterplane Area: 69,486 Square feet or 6,455 Square metres
 Displacement factor (Displacement / loading): 105 %
 Structure weight / hull surface area: 212 lbs/sq ft or 1,036 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.98
  - Longitudinal: 1.19
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is excellent
 Room for accommodation and workspaces is excellent