I thought that it would be interesting to try a 1921-style 48,500 ton battlecruiser

I have long been interested in desigining a viable 1921-style British battlecruiser of 48,500 tons. I just failed at producing a viable design at that normal displacement. this design has a transom stern, 9-16in guns, and 31 knots. To do that required 51,600 tons normal, and that with lightweight machinery. The problem may be that I want a This is the Springsharp report:

GB/CB/1921, Great Britain Battlecruiser laid down 1921 (Engine 1927)

Displacement:
 47,444 t light; 49,521 t standard; 51,600 t normal; 53,263 t full load

Dimensions: Length overall / water x beam x draught
 859.38 ft / 855.00 ft x 108.00 ft x 32.00 ft (normal load)
 261.94 m / 260.60 m x 32.92 m  x 9.75 m

Armament:
      9 - 16.00" / 406 mm guns (3x3 guns), 2,048.00lbs / 928.96kg shells, 1921 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, majority forward, 1 raised mount - superfiring
      16 - 6.00" / 152 mm guns (8x2 guns), 108.00lbs / 48.99kg shells, 1921 Model
   Quick firing guns in turrets (on barbettes)
   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, all raised mounts
      24 - 1.57" / 40.0 mm guns (2 mounts), 2.00lbs / 0.91kg shells, 1921 Model
   Breech loading guns in deck mounts 
   on side, evenly spread, 16 raised guns
 Weight of broadside 20,519 lbs / 9,307 kg
 Shells per gun, main battery: 90

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 13.0" / 330 mm 560.00 ft / 170.69 m 16.00 ft / 4.88 m
 Ends: Unarmoured
   Main Belt covers 101 % of normal length

   - Torpedo Bulkhead:
  3.00" / 76 mm 560.00 ft / 170.69 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: 3.00" / 76 mm 3.00" / 76 mm  3.00" / 76 mm

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

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 168,401 shp / 125,627 Kw = 31.00 kts
 Range 5,600nm at 15.00 kts
 Bunker at max displacement = 3,742 tons

Complement:
 1,711 - 2,225

Cost:
 £11.605 million / $46.421 million

Distribution of weights at normal displacement:
 Armament: 2,565 tons, 5.0 %
 Armour: 18,393 tons, 35.6 %
    - Belts: 4,977 tons, 9.6 %
    - Torpedo bulkhead: 1,927 tons, 3.7 %
    - Armament: 4,491 tons, 8.7 %
    - Armour Deck: 6,581 tons, 12.8 %
    - Conning Tower: 418 tons, 0.8 %
 Machinery: 5,316 tons, 10.3 %
 Hull, fittings & equipment: 21,170 tons, 41.0 %
 Fuel, ammunition & stores: 4,156 tons, 8.1 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   77,635 lbs / 35,215 Kg = 37.9 x 16.0 " / 406 mm shells or 11.9 torpedoes
 Stability (Unstable if below 1.00): 1.08
 Metacentric height 6.5 ft / 2.0 m
 Roll period: 17.8 seconds
 Steadiness - As gun platform (Average = 50 %): 61 %
   - Recoil effect (Restricted arc if above 1.00): 0.83
 Seaboat quality  (Average = 1.00): 1.23

Hull form characteristics:
 Hull has a flush deck
   and transom stern
 Block coefficient: 0.611
 Length to Beam Ratio: 7.92 : 1
 'Natural speed' for length: 33.59 kts
 Power going to wave formation at top speed: 52 %
 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 %): 27.00 ft / 8.23 m
    - Mid (50 %):  27.00 ft / 8.23 m
    - Quarterdeck (15 %): 27.00 ft / 8.23 m
    - Stern:  27.00 ft / 8.23 m
    - Average freeboard: 27.56 ft / 8.40 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 87.1 %
  - Above water (accommodation/working, high = better): 213.8 %
 Waterplane Area: 71,143 Square feet or 6,609 Square metres
 Displacement factor (Displacement / loading): 104 %
 Structure weight / hull surface area: 214 lbs/sq ft or 1,047 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.97
  - Longitudinal: 1.31
  - 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

What if the US had intelligence about the Yamata class?

We wonder what sort of ship the United States might have built, if they had intelligence about the true nature of the Yamato class. I would think that they would have built a large, fast ship. Thanks to the wonder that is Springsharp, we can do a quick-and-dirty design for such a ship. We don't have to ponder the details, we can just design it. I wanted 30 knots and 18in guns. There is the usual DP armament, but with 24 guns. Then there is the light AA armament, as you would expected. I used a 17in belt with 18in on barbettes and turret faces. I have opted for a conventional hull shape, for better anti-torpedo protection. The displacement is really not so great as you might expect:

US/BB/1941, United States Battleship laid down 1941

Displacement:
 77,771 t light; 81,454 t standard; 86,000 t normal; 89,637 t full load

Dimensions: Length overall / water x beam x draught
 979.59 ft / 975.00 ft x 130.00 ft x 35.00 ft (normal load)
 298.58 m / 297.18 m x 39.62 m  x 10.67 m

Armament:
      9 - 18.00" / 457 mm guns (3x3 guns), 2,916.00lbs / 1,322.68kg shells, 1941 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, 1941 Model
   Dual purpose guns in turrets (on barbettes)
   on side, all amidships, 4 raised mounts - superfiring
      64 - 1.57" / 40.0 mm guns (16x4 guns), 1.95lbs / 0.89kg shells, 1941 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread, 12 raised mounts
      36 - 0.79" / 20.0 mm guns in single mounts, 0.24lbs / 0.11kg shells, 1941 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread, 24 raised mounts
 Weight of broadside 27,878 lbs / 12,645 kg
 Shells per gun, main battery: 125

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 17.0" / 432 mm 740.00 ft / 225.55 m 17.00 ft / 5.18 m
 Ends: Unarmoured
   Main Belt covers 117 % of normal length

   - Torpedo Bulkhead:
  6.00" / 152 mm 740.00 ft / 225.55 m 34.00 ft / 10.36 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 18.0" / 457 mm 11.0" / 279 mm  18.0" / 457 mm
 2nd: 5.00" / 127 mm 5.00" / 127 mm  5.00" / 127 mm
 3rd: 1.00" / 25 mm       -         -
 4th: 1.00" / 25 mm       -         -

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

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 230,262 shp / 171,775 Kw = 30.00 kts
 Range 10,000nm at 15.00 kts
 Bunker at max displacement = 8,183 tons

Complement:
 2,510 - 3,264

Cost:
 £40.188 million / $160.754 million

Distribution of weights at normal displacement:
 Armament: 3,485 tons, 4.1 %
 Armour: 37,025 tons, 43.1 %
    - Belts: 8,964 tons, 10.4 %
    - Torpedo bulkhead: 5,586 tons, 6.5 %
    - Armament: 6,972 tons, 8.1 %
    - Armour Deck: 14,748 tons, 17.1 %
    - Conning Tower: 756 tons, 0.9 %
 Machinery: 6,085 tons, 7.1 %
 Hull, fittings & equipment: 31,176 tons, 36.3 %
 Fuel, ammunition & stores: 8,229 tons, 9.6 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   164,036 lbs / 74,405 Kg = 56.3 x 18.0 " / 457 mm shells or 38.5 torpedoes
 Stability (Unstable if below 1.00): 1.17
 Metacentric height 10.0 ft / 3.0 m
 Roll period: 17.3 seconds
 Steadiness - As gun platform (Average = 50 %): 67 %
   - Recoil effect (Restricted arc if above 1.00): 0.54
 Seaboat quality  (Average = 1.00): 1.34

Hull form characteristics:
 Hull has a flush deck
 Block coefficient: 0.679
 Length to Beam Ratio: 7.50 : 1
 'Natural speed' for length: 31.22 kts
 Power going to wave formation at top speed: 49 %
 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 %): 28.00 ft / 8.53 m
    - Mid (50 %):  28.00 ft / 8.53 m
    - Quarterdeck (15 %): 28.00 ft / 8.53 m
    - Stern:  28.00 ft / 8.53 m
    - Average freeboard: 28.72 ft / 8.75 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 64.7 %
  - Above water (accommodation/working, high = better): 211.7 %
 Waterplane Area: 99,650 Square feet or 9,258 Square metres
 Displacement factor (Displacement / loading): 112 %
 Structure weight / hull surface area: 233 lbs/sq ft or 1,138 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.99
  - Longitudinal: 1.11
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is excellent
 Room for accommodation and workspaces is excellent
 Good seaboat, rides out heavy weather easily

How about a Modernized "Super Queen Victoria" class battleship?

I would choose to design a modernized Super Queen Victoria class ship, as that is my concept and not someone elses. I would go for improved deck armour, anti-torpedo protection, increased beam through bulges of the West Virginia type, and a somewhat higher speed. There should be some benefit to having much ligher weight machinery, after all. I like the twin 4.5in DP mount, so my design has 10 twin mounts, giving 20-4.5in DP guns. I also have a light AA armament. For this to work right, it is apparently necessary to reset the laid down date to the date when the modernization would start, in my case 1939. This is the Springsharp report:

Modernized Super Queen Victoria Class, Great Britain Battleship laid down 1939

Displacement:
 47,129 t light; 49,261 t standard; 51,500 t normal; 53,291 t full load

Dimensions: Length overall / water x beam x draught
 760.00 ft / 760.00 ft x 114.00 ft x 31.00 ft (normal load)
 231.65 m / 231.65 m x 34.75 m  x 9.45 m

Armament:
      8 - 16.00" / 406 mm guns (4x2 guns), 2,048.00lbs / 928.96kg shells, 1939 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 2 raised mounts - superfiring
      2 - 16.00" / 406 mm guns (1x2 guns), 2,048.00lbs / 928.96kg shells, 1939 Model
   Breech loading guns in a turret (on a barbette)
   on side amidships
      20 - 4.50" / 114 mm guns (10x2 guns), 45.56lbs / 20.67kg shells, 1939 Model
   Dual purpose guns in turrets (on barbettes)
   on side, evenly spread
      56 - 1.57" / 40.0 mm guns (14x4 guns), 1.95lbs / 0.89kg shells, 1939 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread, 8 raised mounts
      36 - 0.79" / 20.0 mm guns (18x2 guns), 0.24lbs / 0.11kg shells, 1939 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread, 12 raised mounts
 Weight of broadside 21,509 lbs / 9,756 kg
 Shells per gun, main battery: 90

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 14.0" / 356 mm 530.00 ft / 161.54 m 16.00 ft / 4.88 m
 Ends: 6.00" / 152 mm 230.00 ft / 70.10 m 16.00 ft / 4.88 m
   Main Belt covers 107 % of normal length

   - Torpedo Bulkhead:
  3.00" / 76 mm 530.00 ft / 161.54 m 30.00 ft / 9.14 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 14.0" / 356 mm 9.00" / 229 mm  14.0" / 356 mm
 2nd: 14.0" / 356 mm 9.00" / 229 mm  14.0" / 356 mm
 3rd: 4.00" / 102 mm 4.00" / 102 mm  4.00" / 102 mm
 4th: 1.00" / 25 mm       -         -
 5th: 1.00" / 25 mm       -         -

   - Armour deck: 6.00" / 152 mm, Conning tower: 8.00" / 203 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 122,190 shp / 91,153 Kw = 27.00 kts
 Range 6,500nm at 15.00 kts
 Bunker at max displacement = 4,030 tons

Complement:
 1,709 - 2,222

Cost:
 £25.430 million / $101.721 million

Distribution of weights at normal displacement:
 Armament: 2,689 tons, 5.2 %
 Armour: 20,909 tons, 40.6 %
    - Belts: 5,933 tons, 11.5 %
    - Torpedo bulkhead: 1,765 tons, 3.4 %
    - Armament: 5,462 tons, 10.6 %
    - Armour Deck: 7,510 tons, 14.6 %
    - Conning Tower: 239 tons, 0.5 %
 Machinery: 3,306 tons, 6.4 %
 Hull, fittings & equipment: 20,225 tons, 39.3 %
 Fuel, ammunition & stores: 4,371 tons, 8.5 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   87,838 lbs / 39,843 Kg = 42.9 x 16.0 " / 406 mm shells or 15.8 torpedoes
 Stability (Unstable if below 1.00): 1.09
 Metacentric height 7.2 ft / 2.2 m
 Roll period: 17.8 seconds
 Steadiness - As gun platform (Average = 50 %): 60 %
   - Recoil effect (Restricted arc if above 1.00): 0.69
 Seaboat quality  (Average = 1.00): 1.20

Hull form characteristics:
 Hull has a flush deck
 Block coefficient: 0.671
 Length to Beam Ratio: 6.67 : 1
 'Natural speed' for length: 27.57 kts
 Power going to wave formation at top speed: 51 %
 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 %): 27.00 ft / 8.23 m
    - Mid (67 %):  27.00 ft / 8.23 m
    - Quarterdeck (15 %): 19.00 ft / 5.79 m
    - Stern:  19.00 ft / 5.79 m
    - Average freeboard: 25.48 ft / 7.77 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 73.3 %
  - Above water (accommodation/working, high = better): 195.3 %
 Waterplane Area: 67,662 Square feet or 6,286 Square metres
 Displacement factor (Displacement / loading): 105 %
 Structure weight / hull surface area: 221 lbs/sq ft or 1,081 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.96
  - Longitudinal: 1.39
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is excellent
 Room for accommodation and workspaces is excellent
 Good seaboat, rides out heavy weather easily

The proprietor of the Wolf's Shipyard has his alternate history ships

Since I was designing a Kii and Owari-style ship, I looked at references to them and noticed, again, that the Wolf's Shipyard has a page of drawings that includes them.

Battlecruiser version of the Super Queen Victoria class

I was thinking of the Kii and Owari, specifically, when I thought I would try a battlecruiser version of the Super Queen Victoria class. Of course, the Kii and Owari were fast battleships, but they would have been very similar to the Amagi class battlecruisers. Perhaps because my ships seem to be better protected, they are much larger. I also suspect that is because of the vagaries of Springsharp. If we had used lighter machinery, the result would be more in line with the prototype. This is the Springsharp report:

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

Displacement:
 46,578 t light; 48,670 t standard; 51,200 t normal; 53,224 t full load

Dimensions: Length overall / water x beam x draught
 825.00 ft / 825.00 ft x 108.00 ft x 32.00 ft (normal load)
 251.46 m / 251.46 m x 32.92 m  x 9.75 m

Armament:
      8 - 16.00" / 406 mm guns (4x2 guns), 2,211.00lbs / 1,002.89kg shells, 1915 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 2 raised mounts - superfiring
      2 - 16.00" / 406 mm guns (1x2 guns), 2,211.00lbs / 1,002.89kg shells, 1915 Model
   Breech loading guns in a turret (on a barbette)
   on side amidships
      16 - 5.50" / 140 mm guns in single mounts, 83.19lbs / 37.73kg 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 with hoists
   on side, evenly spread, all raised mounts
 Weight of broadside 23,505 lbs / 10,662 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 550.00 ft / 167.64 m 16.00 ft / 4.88 m
 Ends: 6.00" / 152 mm 270.00 ft / 82.30 m 16.00 ft / 4.88 m
   5.00 ft / 1.52 m Unarmoured ends
   Main Belt covers 103 % of normal length

   - Torpedo Bulkhead:
  2.00" / 51 mm 550.00 ft / 167.64 m 31.00 ft / 9.45 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 13.0" / 330 mm 8.00" / 203 mm  13.0" / 330 mm
 2nd: 13.0" / 330 mm 8.00" / 203 mm  13.0" / 330 mm
 3rd: 4.00" / 102 mm 1.00" / 25 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, 172,432 shp / 128,635 Kw = 30.00 kts
 Range 5,200nm at 15.00 kts
 Bunker at max displacement = 4,554 tons

Complement:
 1,701 - 2,212

Cost:
 £7.042 million / $28.169 million

Distribution of weights at normal displacement:
 Armament: 2,734 tons, 5.3 %
 Armour: 16,482 tons, 32.2 %
    - Belts: 5,477 tons, 10.7 %
    - Torpedo bulkhead: 1,262 tons, 2.5 %
    - Armament: 4,406 tons, 8.6 %
    - Armour Deck: 4,952 tons, 9.7 %
    - Conning Tower: 386 tons, 0.8 %
 Machinery: 6,532 tons, 12.8 %
 Hull, fittings & equipment: 20,830 tons, 40.7 %
 Fuel, ammunition & stores: 4,622 tons, 9.0 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   61,771 lbs / 28,019 Kg = 30.2 x 16.0 " / 406 mm shells or 8.2 torpedoes
 Stability (Unstable if below 1.00): 1.10
 Metacentric height 6.7 ft / 2.0 m
 Roll period: 17.5 seconds
 Steadiness - As gun platform (Average = 50 %): 52 %
   - Recoil effect (Restricted arc if above 1.00): 0.81
 Seaboat quality  (Average = 1.00): 1.05

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.629
 Length to Beam Ratio: 7.64 : 1
 'Natural speed' for length: 28.72 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:  30.00 ft / 9.14 m
    - Forecastle (20 %): 27.00 ft / 8.23 m
    - Mid (67 %):  27.00 ft / 8.23 m (18.00 ft / 5.49 m aft of break)
    - Quarterdeck (15 %): 19.00 ft / 5.79 m
    - Stern:  19.00 ft / 5.79 m
    - Average freeboard: 24.51 ft / 7.47 m
 Ship tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 101.8 %
  - Above water (accommodation/working, high = better): 184.7 %
 Waterplane Area: 66,918 Square feet or 6,217 Square metres
 Displacement factor (Displacement / loading): 100 %
 Structure weight / hull surface area: 224 lbs/sq ft or 1,094 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.98
  - Longitudinal: 1.15
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is adequate
 Room for accommodation and workspaces is excellent

My concept for a "Super Queen Victoria" class

To my mind, a natural expansion of the Queen Victoria class would be to go with 16in guns. Due to the date, the secondary armament probably should be 5.5in guns. The speed could go up to 25 knots, and the result would be comparable to what the Japanese were planning. The greatest challenge was to keep the stability to an acceptable value and keep the recoil issue within bounds. Hull strength could be easily dealt with simply by increasing the displacement further. With the greater length, 25 knots is easily achieved. This is my initial cut at a Springsharp design:

Super Queen Victoria Class, Great Britain Battleship laid down 1915

Displacement:
 41,690 t light; 43,682 t standard; 46,200 t normal; 48,214 t full load

Dimensions: Length overall / water x beam x draught
 760.00 ft / 760.00 ft x 108.00 ft x 32.00 ft (normal load)
 231.65 m / 231.65 m x 32.92 m  x 9.75 m

Armament:
      8 - 16.00" / 406 mm guns (4x2 guns), 2,211.00lbs / 1,002.89kg shells, 1915 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 2 raised mounts - superfiring
      2 - 16.00" / 406 mm guns (1x2 guns), 2,211.00lbs / 1,002.89kg shells, 1915 Model
   Breech loading guns in a turret (on a barbette)
   on side amidships
      16 - 5.50" / 140 mm guns in single mounts, 83.19lbs / 37.73kg 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 with hoists
   on side, evenly spread, all raised mounts
 Weight of broadside 23,505 lbs / 10,662 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 530.00 ft / 161.54 m 16.00 ft / 4.88 m
 Ends: 6.00" / 152 mm 230.00 ft / 70.10 m 16.00 ft / 4.88 m
   Main Belt covers 107 % of normal length

   - Torpedo Bulkhead:
  2.00" / 51 mm 530.00 ft / 161.54 m 31.00 ft / 9.45 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 14.0" / 356 mm 9.00" / 229 mm  14.0" / 356 mm
 2nd: 14.0" / 356 mm 9.00" / 229 mm  14.0" / 356 mm
 3rd: 4.00" / 102 mm 1.00" / 25 mm  4.00" / 102 mm

   - Armour deck: 4.00" / 102 mm, Conning tower: 14.00" / 356 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 82,173 shp / 61,301 Kw = 25.00 kts
 Range 5,600nm at 15.00 kts
 Bunker at max displacement = 4,532 tons

Complement:
 1,575 - 2,048

Cost:
 £6.097 million / $24.389 million

Distribution of weights at normal displacement:
 Armament: 2,734 tons, 5.9 %
 Armour: 16,656 tons, 36.1 %
    - Belts: 5,889 tons, 12.7 %
    - Torpedo bulkhead: 1,216 tons, 2.6 %
    - Armament: 4,655 tons, 10.1 %
    - Armour Deck: 4,508 tons, 9.8 %
    - Conning Tower: 388 tons, 0.8 %
 Machinery: 3,113 tons, 6.7 %
 Hull, fittings & equipment: 19,187 tons, 41.5 %
 Fuel, ammunition & stores: 4,510 tons, 9.8 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   66,312 lbs / 30,078 Kg = 32.4 x 16.0 " / 406 mm shells or 10.4 torpedoes
 Stability (Unstable if below 1.00): 1.05
 Metacentric height 6.2 ft / 1.9 m
 Roll period: 18.2 seconds
 Steadiness - As gun platform (Average = 50 %): 70 %
   - Recoil effect (Restricted arc if above 1.00): 0.96
 Seaboat quality  (Average = 1.00): 1.41

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.616
 Length to Beam Ratio: 7.04 : 1
 'Natural speed' for length: 27.57 kts
 Power going to wave formation at top speed: 45 %
 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 %): 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: 23.60 ft / 7.19 m
 Ship tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 83.2 %
  - Above water (accommodation/working, high = better): 175.2 %
 Waterplane Area: 60,913 Square feet or 5,659 Square metres
 Displacement factor (Displacement / loading): 103 %
 Structure weight / hull surface area: 228 lbs/sq ft or 1,112 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.97
  - Longitudinal: 1.37
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is excellent
 Room for accommodation and workspaces is excellent
 Ship has slow, easy roll, a good, steady gun platform
 Good seaboat, rides out heavy weather easily

My version of the "Queen Victoria" class

I was originally inspired to try my had at photoart by the Queen Victoria Class Battleship page. I like the basic concept for the design: a more heavily armed and protected version of the Queen Elizabeth class that sacrifices some speed to achieve those goals. When we realize that the actual Queen Elizabeth class ships underperformed, so that they only could reach 23.5 to 24 knots, the sacrifice is pretty minimal. This is my version of the design. There are really only minimal differences. I would retain the plow bow, for example:

GB/BB/1913, Great Britain Battleship laid down 1913

Displacement:
 32,989 t light; 34,788 t standard; 36,700 t normal; 38,230 t full load

Dimensions: Length overall / water x beam x draught
 730.00 ft / 730.00 ft x 98.00 ft x 31.00 ft (normal load)
 222.50 m / 222.50 m x 29.87 m  x 9.45 m

Armament:
     8 - 15.00" / 381 mm guns (4x2 guns), 1,920.00lbs / 870.90kg shells, 1913 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread
     2 - 15.00" / 381 mm guns (1x2 guns), 1,920.00lbs / 870.90kg shells, 1913 Model
   Breech loading guns in a turret (on a barbette)
   on centreline amidships
     14 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1913 Model
   Quick firing guns in casemate mounts
   on centreline, all amidships
   14 guns in hull casemates - Limited use in heavy seas
     2 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1913 Model
   Anti-aircraft guns in deck mounts
   on side, evenly spread
 Weight of broadside 20,776 lbs / 9,424 kg
 Shells per gun, main battery: 90
 4 - 21.0" / 533.4 mm submerged torpedo tubes

Armour:
  - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 13.0" / 330 mm 520.00 ft / 158.50 m 16.00 ft / 4.88 m
 Ends: 6.00" / 152 mm 210.00 ft / 64.01 m 16.00 ft / 4.88 m
   Main Belt covers 110 % of normal length

  - Torpedo Bulkhead:
  2.00" / 51 mm 520.00 ft / 158.50 m 30.00 ft / 9.14 m

  - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 13.0" / 330 mm 7.00" / 178 mm  13.0" / 330 mm
 2nd: 13.0" / 330 mm 7.00" / 178 mm  13.0" / 330 mm
 3rd: 6.00" / 152 mm 6.00" / 152 mm  6.00" / 152 mm

  - Armour deck: 3.00" / 76 mm, Conning tower: 13.00" / 330 mm

Machinery:
 Oil fired boilers, steam turbines,
 Direct drive, 4 shafts, 56,047 shp / 41,811 Kw = 23.50 kts
 Range 4,500nm at 15.00 kts
 Bunker at max displacement = 3,442 tons

Complement:
 1,325 - 1,723

Cost:
 £3.708 million / $14.834 million

Distribution of weights at normal displacement:
 Armament: 2,306 tons, 6.3 %
 Armour: 13,298 tons, 36.2 %
    - Belts: 5,313 tons, 14.5 %
    - Torpedo bulkhead: 1,154 tons, 3.1 %
    - Armament: 3,673 tons, 10.0 %
    - Armour Deck: 2,848 tons, 7.8 %
    - Conning Tower: 309 tons, 0.8 %
 Machinery: 2,196 tons, 6.0 %
 Hull, fittings & equipment: 15,188 tons, 41.4 %
 Fuel, ammunition & stores: 3,711 tons, 10.1 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   53,580 lbs / 24,303 Kg = 31.8 x 15.0 " / 381 mm shells or 8.3 torpedoes
 Stability (Unstable if below 1.00): 1.10
 Metacentric height 5.9 ft / 1.8 m
 Roll period: 17.0 seconds
 Steadiness - As gun platform (Average = 50 %): 73 %
   - Recoil effect (Restricted arc if above 1.00): 0.96
 Seaboat quality  (Average = 1.00): 1.46

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.579
 Length to Beam Ratio: 7.45 : 1
 'Natural speed' for length: 27.02 kts
 Power going to wave formation at top speed: 41 %
 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 tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 86.3 %
  - Above water (accommodation/working, high = better): 168.1 %
 Waterplane Area: 51,314 Square feet or 4,767 Square metres
 Displacement factor (Displacement / loading): 102 %
 Structure weight / hull surface area: 207 lbs/sq ft or 1,011 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.97
  - Longitudinal: 1.45
  - Overall: 1.01
 Hull space for machinery, storage, compartmentation is adequate
 Room for accommodation and workspaces is excellent
 Ship has slow, easy roll, a good, steady gun platform
 Good seaboat, rides out heavy weather easily

A Super Lion "lite"

I was able to get a light version of the Super Lion to a point where the characteristics were acceptable. I wanted 6in armour, 30 knots, 10-15in, 14-6in, 2-4in AA guns, and a reasonable range. To achieve an acceptable design, the beam grew to 100ft. The issue was the recoil from the 10-15in gun broadside. Springsharp is concerned about such things, so therefore, I am. I was able to keep the displacement down to the range I wanted. This is the Springsharp report (if you see any issues, I would appreciate knowing):

Super Lion-lite, Great Britain Battlecruiser laid down 1912 (Engine 1927)

Displacement:
 31,825 t light; 33,471 t standard; 35,250 t normal; 36,674 t full load

Dimensions: Length overall / water x beam x draught
 735.00 ft / 735.00 ft x 100.00 ft x 30.00 ft (normal load)
 224.03 m / 224.03 m x 30.48 m  x 9.14 m

Armament:
      8 - 15.00" / 381 mm guns (4x2 guns), 1,920.00lbs / 870.90kg shells, 1912 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 2 raised mounts - superfiring
      2 - 15.00" / 381 mm guns (1x2 guns), 1,920.00lbs / 870.90kg shells, 1912 Model
   Breech loading guns in a turret (on a barbette)
   on centreline amidships
      14 - 6.00" / 152 mm guns in single mounts, 100.00lbs / 45.36kg shells, 1912 Model
   Quick firing guns in casemate mounts 
   on side, evenly spread, 6 raised mounts
      2 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1912 Model
   Anti-aircraft guns in deck mounts with hoists
   on side, all amidships, all raised mounts - superfiring
 Weight of broadside 20,664 lbs / 9,373 kg
 Shells per gun, main battery: 80

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 6.00" / 152 mm 550.00 ft / 167.64 m 16.00 ft / 4.88 m
 Ends: 4.00" / 102 mm 185.00 ft / 56.39 m 12.00 ft / 3.66 m
   Main Belt covers 115 % of normal length

   - Torpedo Bulkhead:
  2.00" / 51 mm 550.00 ft / 167.64 m 29.00 ft / 8.84 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 8.00" / 203 mm 5.00" / 127 mm  8.00" / 203 mm
 2nd: 4.00" / 102 mm 4.00" / 102 mm  4.00" / 102 mm

   - Armour deck: 3.00" / 76 mm, Conning tower: 8.00" / 203 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 139,483 shp / 104,055 Kw = 30.00 kts
 Range 6,000nm at 15.00 kts
 Bunker at max displacement = 3,203 tons

Complement:
 1,286 - 1,672

Cost:
 £3.668 million / $14.671 million

Distribution of weights at normal displacement:
 Armament: 2,306 tons, 6.5 %
 Armour: 8,941 tons, 25.4 %
    - Belts: 2,536 tons, 7.2 %
    - Torpedo bulkhead: 1,180 tons, 3.3 %
    - Armament: 2,167 tons, 6.1 %
    - Armour Deck: 2,872 tons, 8.1 %
    - Conning Tower: 185 tons, 0.5 %
 Machinery: 4,403 tons, 12.5 %
 Hull, fittings & equipment: 16,175 tons, 45.9 %
 Fuel, ammunition & stores: 3,425 tons, 9.7 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   41,454 lbs / 18,803 Kg = 24.6 x 15.0 " / 381 mm shells or 5.8 torpedoes
 Stability (Unstable if below 1.00): 1.12
 Metacentric height 6.2 ft / 1.9 m
 Roll period: 16.9 seconds
 Steadiness - As gun platform (Average = 50 %): 53 %
   - Recoil effect (Restricted arc if above 1.00): 0.95
 Seaboat quality  (Average = 1.00): 1.07

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.560
 Length to Beam Ratio: 7.35 : 1
 'Natural speed' for length: 27.11 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: -1.00 ft / -0.30 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  31.00 ft / 9.45 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: 23.76 ft / 7.24 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 111.7 %
  - Above water (accommodation/working, high = better): 182.3 %
 Waterplane Area: 51,755 Square feet or 4,808 Square metres
 Displacement factor (Displacement / loading): 97 %
 Structure weight / hull surface area: 219 lbs/sq ft or 1,070 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.95
  - Longitudinal: 1.52
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

How about a Super Lion with 30 SHP/ton machinery?

I thought it would interesting to try Admiral Fisher's concept ship, the Super Lion, with 30 SHP/ton machinery. To keep the size down (it is still large), I settled for an 8in belt. The armament is the usual 10-15/42 with 14-6in QF guns and 2-4in AA guns. The speed is the specified 30 knots. With light weight machinery, the ship is fairly interesting. I had started with the lightest weight machinery possible (about 42 SHP/ton) and then derated it to reach the 30 SHP/ton. This is the Springsharp report:

Super Lion, Great Britain Battlecruiser laid down 1912 (Engine 1923)

Displacement:
 34,201 t light; 36,003 t standard; 38,100 t normal; 39,777 t full load

Dimensions: Length overall / water x beam x draught
 745.00 ft / 745.00 ft x 101.00 ft x 30.00 ft (normal load)
 227.08 m / 227.08 m x 30.78 m  x 9.14 m

Armament:
      8 - 15.00" / 381 mm guns (4x2 guns), 1,920.00lbs / 870.90kg shells, 1912 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 2 raised mounts - superfiring
      2 - 15.00" / 381 mm guns (1x2 guns), 1,687.50lbs / 765.44kg shells, 1912 Model
   Breech loading guns in a turret (on a barbette)
   on centreline amidships
      14 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1912 Model
   Quick firing guns in casemate mounts 
   on side, all amidships, 6 raised mounts - superfiring
      2 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1912 Model
   Anti-aircraft guns in deck mounts with hoists
   on side, all amidships, all raised mounts - superfiring
 Weight of broadside 20,311 lbs / 9,213 kg
 Shells per gun, main battery: 90
 4 - 21.0" / 533.4 mm above water torpedoes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 8.00" / 203 mm 520.00 ft / 158.50 m 16.00 ft / 4.88 m
 Ends: 4.00" / 102 mm 225.00 ft / 68.58 m 12.00 ft / 3.66 m
   Main Belt covers 107 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  2.00" / 51 mm 520.00 ft / 158.50 m 27.00 ft / 8.23 m

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

   - Armour deck: 3.00" / 76 mm, Conning tower: 10.00" / 254 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 147,605 shp / 110,113 Kw = 30.00 kts
 Range 6,500nm at 15.00 kts
 Bunker at max displacement = 3,774 tons

Complement:
 1,363 - 1,772

Cost:
 £3.825 million / $15.300 million

Distribution of weights at normal displacement:
 Armament: 2,306 tons, 6.1 %
 Armour: 10,290 tons, 27.0 %
    - Belts: 3,226 tons, 8.5 %
    - Torpedo bulkhead: 1,039 tons, 2.7 %
    - Armament: 2,754 tons, 7.2 %
    - Armour Deck: 3,028 tons, 7.9 %
    - Conning Tower: 244 tons, 0.6 %
 Machinery: 4,933 tons, 12.9 %
 Hull, fittings & equipment: 16,671 tons, 43.8 %
 Fuel, ammunition & stores: 3,899 tons, 10.2 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   45,287 lbs / 20,542 Kg = 26.8 x 15.0 " / 381 mm shells or 6.1 torpedoes
 Stability (Unstable if below 1.00): 1.11
 Metacentric height 6.2 ft / 1.9 m
 Roll period: 17.0 seconds
 Steadiness - As gun platform (Average = 50 %): 51 %
   - Recoil effect (Restricted arc if above 1.00): 0.88
 Seaboat quality  (Average = 1.00): 1.03

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.591
 Length to Beam Ratio: 7.38 : 1
 'Natural speed' for length: 27.29 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: -1.00 ft / -0.30 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  31.00 ft / 9.45 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: 23.76 ft / 7.24 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 109.2 %
  - Above water (accommodation/working, high = better): 174.7 %
 Waterplane Area: 54,558 Square feet or 5,069 Square metres
 Displacement factor (Displacement / loading): 99 %
 Structure weight / hull surface area: 217 lbs/sq ft or 1,058 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.96
  - Longitudinal: 1.40
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is adequate
 Room for accommodation and workspaces is excellent

So is an HMS Arethusa (1912) feasible in Springsharp?

Last night, the question I had was if an HMS Arethusa (1912) style design would work in Springsharp. I tried it this morning, and was pleased with the result. I was handicapped by only having Conway's book for specification, but I think I have a credible version that is not too far off from reality. My goals were to have the right sort of machinery weight and bunker capacity, and that worked well. This is the Springsharp report:

GB/CS/1912, Great Britain Scout Cruiser laid down 1912 (Engine 1921)

Displacement:
 4,784 t light; 4,969 t standard; 5,390 t normal; 5,727 t full load

Dimensions: Length overall / water x beam x draught
 476.31 ft / 475.00 ft x 45.00 ft x 16.00 ft (normal load)
 145.18 m / 144.78 m x 13.72 m  x 4.88 m

Armament:
      6 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1912 Model
   Quick firing guns in deck mounts with hoists
   on centreline ends, evenly spread, 2 raised mounts - superfiring
      2 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1912 Model
   Anti-aircraft guns in deck mounts with hoists
   on side, all amidships
      12 - 1.57" / 40.0 mm guns (6x2 guns), 2.00lbs / 0.91kg shells, 1912 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread
 Weight of broadside 736 lbs / 334 kg
 Shells per gun, main battery: 180
 8 - 21.0" / 533.4 mm above water torpedoes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 3.00" / 76 mm 360.00 ft / 109.73 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: 4.00" / 102 mm 1.00" / 25 mm  2.00" / 51 mm

   - Armour deck: 1.50" / 38 mm, Conning tower: 4.00" / 102 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 2 shafts, 49,462 shp / 36,899 Kw = 30.00 kts
 Range 4,200nm at 15.00 kts
 Bunker at max displacement = 758 tons

Complement:
 313 - 408

Cost:
 £0.483 million / $1.932 million

Distribution of weights at normal displacement:
 Armament: 92 tons, 1.7 %
 Armour: 1,028 tons, 19.1 %
    - Belts: 527 tons, 9.8 %
    - Torpedo bulkhead: 0 tons, 0.0 %
    - Armament: 60 tons, 1.1 %
    - Armour Deck: 415 tons, 7.7 %
    - Conning Tower: 26 tons, 0.5 %
 Machinery: 1,703 tons, 31.6 %
 Hull, fittings & equipment: 1,961 tons, 36.4 %
 Fuel, ammunition & stores: 606 tons, 11.2 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   5,028 lbs / 2,281 Kg = 46.6 x 6.0 " / 152 mm shells or 0.9 torpedoes
 Stability (Unstable if below 1.00): 1.24
 Metacentric height 2.2 ft / 0.7 m
 Roll period: 12.6 seconds
 Steadiness - As gun platform (Average = 50 %): 57 %
   - Recoil effect (Restricted arc if above 1.00): 0.43
 Seaboat quality  (Average = 1.00): 1.15

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.552
 Length to Beam Ratio: 10.56 : 1
 'Natural speed' for length: 21.79 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: 0.00 ft / 0.00 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 (36 %):  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: 17.12 ft / 5.22 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 116.1 %
  - Above water (accommodation/working, high = better): 107.7 %
 Waterplane Area: 14,940 Square feet or 1,388 Square metres
 Displacement factor (Displacement / loading): 104 %
 Structure weight / hull surface area: 75 lbs/sq ft or 368 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.95
  - Longitudinal: 1.61
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is adequate

A "nice" 1912 British light cruiser

By using rather light machinery (although not excessively so, at 29 SHP/ton), a 30-knot British light cruiser for 1912 with 6-6in guns on the broadside is possible. The displacement is about that of a Town class and the machinery weight is not as agressive as that of the Arethusa class (47 SHP/ton desired). Admittedly, this looks a lot like a D-class ship, except earlier in time. This is the Springsharp report:

GB/CS/1912, Great Britain Scout Cruiser laid down 1912 (Engine 1921)

Displacement:
 4,784 t light; 4,969 t standard; 5,390 t normal; 5,727 t full load

Dimensions: Length overall / water x beam x draught
 476.31 ft / 475.00 ft x 45.00 ft x 16.00 ft (normal load)
 145.18 m / 144.78 m x 13.72 m  x 4.88 m

Armament:
      6 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1912 Model
   Quick firing guns in deck mounts with hoists
   on centreline ends, evenly spread, 2 raised mounts - superfiring
      2 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1912 Model
   Anti-aircraft guns in deck mounts with hoists
   on side, all amidships
      12 - 1.57" / 40.0 mm guns (6x2 guns), 2.00lbs / 0.91kg shells, 1912 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread
 Weight of broadside 736 lbs / 334 kg
 Shells per gun, main battery: 180
 8 - 21.0" / 533.4 mm above water torpedoes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 3.00" / 76 mm 360.00 ft / 109.73 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: 4.00" / 102 mm 1.00" / 25 mm  2.00" / 51 mm

   - Armour deck: 1.50" / 38 mm, Conning tower: 4.00" / 102 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 2 shafts, 49,462 shp / 36,899 Kw = 30.00 kts
 Range 4,200nm at 15.00 kts
 Bunker at max displacement = 758 tons

Complement:
 313 - 408

Cost:
 £0.483 million / $1.932 million

Distribution of weights at normal displacement:
 Armament: 92 tons, 1.7 %
 Armour: 1,028 tons, 19.1 %
    - Belts: 527 tons, 9.8 %
    - Torpedo bulkhead: 0 tons, 0.0 %
    - Armament: 60 tons, 1.1 %
    - Armour Deck: 415 tons, 7.7 %
    - Conning Tower: 26 tons, 0.5 %
 Machinery: 1,703 tons, 31.6 %
 Hull, fittings & equipment: 1,961 tons, 36.4 %
 Fuel, ammunition & stores: 606 tons, 11.2 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   5,028 lbs / 2,281 Kg = 46.6 x 6.0 " / 152 mm shells or 0.9 torpedoes
 Stability (Unstable if below 1.00): 1.24
 Metacentric height 2.2 ft / 0.7 m
 Roll period: 12.6 seconds
 Steadiness - As gun platform (Average = 50 %): 57 %
   - Recoil effect (Restricted arc if above 1.00): 0.43
 Seaboat quality  (Average = 1.00): 1.15

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.552
 Length to Beam Ratio: 10.56 : 1
 'Natural speed' for length: 21.79 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: 0.00 ft / 0.00 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 (36 %):  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: 17.12 ft / 5.22 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 116.1 %
  - Above water (accommodation/working, high = better): 107.7 %
 Waterplane Area: 14,940 Square feet or 1,388 Square metres
 Displacement factor (Displacement / loading): 104 %
 Structure weight / hull surface area: 75 lbs/sq ft or 368 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.95
  - Longitudinal: 1.61
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is adequate

My attempt at a Fisher-style Super Swift

By dispensing with armour, a Super Swift for 1912 is feasible. That is especially true if we settle for a 36-knot speed. The idea is to have a 2,480 ton ship with 6-4in QF guns and 4-21in TT. We use the lightest weight machinery allowed by Springsharp, which is not as light as we need. Remember that the Swift, a 1905/06 design could get as much as 60 SHP/ton of machinery, and that was running trials about 1907. This is the Springsharp report:

GB/CS/1912, Great Britain Scout Cruiser laid down 1912 (Engine 1950)

Displacement:
 2,147 t light; 2,222 t standard; 2,420 t normal; 2,578 t full load

Dimensions: Length overall / water x beam x draught
 371.36 ft / 370.00 ft x 38.00 ft x 14.00 ft (normal load)
 113.19 m / 112.78 m x 11.58 m  x 4.27 m

Armament:
      6 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1912 Model
   Quick firing guns in deck mounts with hoists
   on side ends, evenly spread
 Weight of broadside 192 lbs / 87 kg
 Shells per gun, main battery: 250
 4 - 21.0" / 533.4 mm above water torpedoes

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 2 shafts, 69,991 shp / 52,214 Kw = 36.00 kts
 Range 4,200nm at 15.00 kts
 Bunker at max displacement = 356 tons

Complement:
 172 - 224

Cost:
 £0.288 million / $1.152 million

Distribution of weights at normal displacement:
 Armament: 24 tons, 1.0 %
 Machinery: 1,376 tons, 56.9 %
 Hull, fittings & equipment: 747 tons, 30.9 %
 Fuel, ammunition & stores: 273 tons, 11.3 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   657 lbs / 298 Kg = 20.5 x 4.0 " / 102 mm shells or 0.3 torpedoes
 Stability (Unstable if below 1.00): 1.46
 Metacentric height 2.2 ft / 0.7 m
 Roll period: 10.7 seconds
 Steadiness - As gun platform (Average = 50 %): 51 %
   - Recoil effect (Restricted arc if above 1.00): 0.19
 Seaboat quality  (Average = 1.00): 1.03

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.430
 Length to Beam Ratio: 9.74 : 1
 'Natural speed' for length: 19.24 kts
 Power going to wave formation at top speed: 71 %
 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:  26.00 ft / 7.92 m
    - Forecastle (20 %): 23.00 ft / 7.01 m
    - Mid (36 %):  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: 18.12 ft / 5.52 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 191.5 %
  - Above water (accommodation/working, high = better): 133.4 %
 Waterplane Area: 8,831 Square feet or 820 Square metres
 Displacement factor (Displacement / loading): 68 %
 Structure weight / hull surface area: 39 lbs/sq ft or 191 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.50
  - Longitudinal: 2.94
  - Overall: 0.60
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

A British super-destroyer for 1923

I wondered if by using the lightest-weight machinery if a British super-destroyer might be possible in 1923. The answer seems to be "yes", if you settle for 38 knots. I may experiment some more, such as with a lighter armament to see if a higher speed (40 knots or more) might be possible. I tried to keep the length from getting too long, but it seemed necessary to have a length greater than 400 ft. I am using an armament of 5-5.5in QF guns, 1-4in AA gun, and 3-quadruple 2pdr AA mounts, with two triple 21in torpedo tubes. This is the Springsharp report:

GB/DL/1923, Great Britain Destroyer Leader laid down 1923 (Engine 1950)

Displacement:
 2,647 t light; 2,747 t standard; 2,950 t normal; 3,112 t full load

Dimensions: Length overall / water x beam x draught
 436.75 ft / 435.00 ft x 42.00 ft x 16.00 ft (normal load)
 133.12 m / 132.59 m x 12.80 m  x 4.88 m

Armament:
      5 - 5.50" / 140 mm guns in single mounts, 83.19lbs / 37.73kg shells, 1923 Model
   Quick firing guns in deck mounts with hoists
   on centreline ends, majority forward, 2 raised mounts - superfiring
      1 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1923 Model
   Anti-aircraft gun in a deck mount with hoist
   on side amidships
      12 - 1.57" / 40.0 mm guns (3x4 guns), 2.00lbs / 0.91kg shells, 1923 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread
 Weight of broadside 472 lbs / 214 kg
 Shells per gun, main battery: 150
 6 - 21.0" / 533.4 mm above water torpedoes

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 2 shafts, 85,263 shp / 63,606 Kw = 38.00 kts
 Range 3,750nm at 15.00 kts
 Bunker at max displacement = 365 tons

Complement:
 199 - 260

Cost:
 £1.109 million / $4.436 million

Distribution of weights at normal displacement:
 Armament: 59 tons, 2.0 %
 Machinery: 1,708 tons, 57.9 %
 Hull, fittings & equipment: 881 tons, 29.9 %
 Fuel, ammunition & stores: 303 tons, 10.3 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   631 lbs / 286 Kg = 7.6 x 5.5 " / 140 mm shells or 0.3 torpedoes
 Stability (Unstable if below 1.00): 1.51
 Metacentric height 2.8 ft / 0.8 m
 Roll period: 10.6 seconds
 Steadiness - As gun platform (Average = 50 %): 51 %
   - Recoil effect (Restricted arc if above 1.00): 0.32
 Seaboat quality  (Average = 1.00): 1.02

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.353
 Length to Beam Ratio: 10.36 : 1
 'Natural speed' for length: 20.86 kts
 Power going to wave formation at top speed: 66 %
 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:  25.00 ft / 7.62 m
    - Forecastle (20 %): 22.00 ft / 6.71 m
    - Mid (37 %):  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: 17.20 ft / 5.24 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 202.0 %
  - Above water (accommodation/working, high = better): 132.1 %
 Waterplane Area: 11,087 Square feet or 1,030 Square metres
 Displacement factor (Displacement / loading): 65 %
 Structure weight / hull surface area: 41 lbs/sq ft or 202 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.46
  - Longitudinal: 1.69
  - Overall: 0.52
 Hull space for machinery, storage, compartmentation is extremely poor
 Room for accommodation and workspaces is excellent

The Russian Battleships site has really gotten good

The case probably is that the Russian Battleship site has always been good, but I looked at the site for the first time in a while and was really impressed. I was particularly impressed by the 3-D models, but it is all really good.

By using 41.8 SHP/ton machinery, I got what I wanted

I was able to design a 36-knot British light cruiser, to be laid down in 1923, that could reach 36 knots. The concept is rather like the Japanese fast light cruisers from the 1920's, except that this design has 9-6in guns, with three in superfiring positions. The protection is pretty meager, but that seems to be what is required to achieve such a high speed, with adequate composite strength and seakeeping. This is the Springsharp report:

GB/CL/1923, Great Britain Light Cruiser laid down 1923 (Engine 1950)

Displacement:
 7,882 t light; 8,164 t standard; 8,700 t normal; 9,129 t full load

Dimensions: Length overall / water x beam x draught
 598.89 ft / 595.00 ft x 56.00 ft x 20.00 ft (normal load)
 182.54 m / 181.36 m x 17.07 m  x 6.10 m

Armament:
      9 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1923 Model
   Breech loading guns in deck mounts with hoists
   on centreline ends, majority forward, 3 raised mounts - superfiring
      4 - 4.70" / 119 mm guns in single mounts, 51.91lbs / 23.55kg shells, 1923 Model
   Anti-aircraft guns in deck mounts 
   on side, all amidships
      24 - 1.57" / 40.0 mm guns (6x4 guns), 1.95lbs / 0.89kg shells, 1923 Model
   Breech loading guns in deck mounts 
   on side, evenly spread
 Weight of broadside 1,227 lbs / 556 kg
 Shells per gun, main battery: 150
 6 - 21.0" / 533.4 mm above water torpedoes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 2.00" / 51 mm 490.00 ft / 149.35 m 12.00 ft / 3.66 m
 Ends: Unarmoured
   Main Belt covers 127 % of normal length

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 3.00" / 76 mm       -   3.00" / 76 mm

   - Armour deck: 1.50" / 38 mm, Conning tower: 3.00" / 76 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 121,185 shp / 90,404 Kw = 36.00 kts
 Range 5,200nm at 15.00 kts
 Bunker at max displacement = 964 tons

Complement:
 449 - 585

Cost:
 £2.358 million / $9.432 million

Distribution of weights at normal displacement:
 Armament: 153 tons, 1.8 %
 Armour: 1,192 tons, 13.7 %
    - Belts: 470 tons, 5.4 %
    - Torpedo bulkhead: 0 tons, 0.0 %
    - Armament: 102 tons, 1.2 %
    - Armour Deck: 593 tons, 6.8 %
    - Conning Tower: 27 tons, 0.3 %
 Machinery: 2,899 tons, 33.3 %
 Hull, fittings & equipment: 3,638 tons, 41.8 %
 Fuel, ammunition & stores: 818 tons, 9.4 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   8,031 lbs / 3,643 Kg = 74.4 x 6.0 " / 152 mm shells or 1.1 torpedoes
 Stability (Unstable if below 1.00): 1.24
 Metacentric height 3.1 ft / 0.9 m
 Roll period: 13.3 seconds
 Steadiness - As gun platform (Average = 50 %): 54 %
   - Recoil effect (Restricted arc if above 1.00): 0.38
 Seaboat quality  (Average = 1.00): 1.09

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.457
 Length to Beam Ratio: 10.63 : 1
 'Natural speed' for length: 24.39 kts
 Power going to wave formation at top speed: 60 %
 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 %): 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): 121.8 %
  - Above water (accommodation/working, high = better): 165.1 %
 Waterplane Area: 21,376 Square feet or 1,986 Square metres
 Displacement factor (Displacement / loading): 106 %
 Structure weight / hull surface area: 97 lbs/sq ft or 473 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.94
  - Longitudinal: 1.72
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

My 1921-style light cruiser with lightweight machinery

Blogger has been down for a number of hours, so I have tried to post about my 1921 British light cruiser design that is attempting to be a 35-knot ship with 6in guns. The E-class ships were a move in this direction. They had moderately light weight machinery, but had a lesser speed goal. I wanted a design with more of an edge, as there were the Japanese light cruisers and the US Omaha class in competition. I really wanted a 36-knot ship, but Springsharp would not accommodate light enough machinery. This is the Springsharp report:

GB/CL/1921, Great Britain Light Cruiser laid down 1921 (Engine 1950)

Displacement:
 6,398 t light; 6,620 t standard; 7,050 t normal; 7,394 t full load

Dimensions: Length overall / water x beam x draught
 558.75 ft / 555.00 ft x 55.00 ft x 18.00 ft (normal load)
 170.31 m / 169.16 m x 16.76 m  x 5.49 m

Armament:
      7 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1921 Model
   Breech loading guns in deck mounts with hoists
   on centreline ends, majority forward
      4 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1921 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, 1921 Model
   Anti-aircraft guns in deck mounts 
   on side, evenly spread
 Weight of broadside 915 lbs / 415 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: 2.00" / 51 mm 450.00 ft / 137.16 m 12.00 ft / 3.66 m
 Ends: Unarmoured
   Main Belt covers 125 % of normal length

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

   - Armour deck: 1.00" / 25 mm, Conning tower: 4.00" / 102 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 98,096 shp / 73,180 Kw = 35.00 kts
 Range 4,750nm at 15.00 kts
 Bunker at max displacement = 775 tons

Complement:
 384 - 500

Cost:
 £1.651 million / $6.604 million

Distribution of weights at normal displacement:
 Armament: 114 tons, 1.6 %
 Armour: 926 tons, 13.1 %
    - Belts: 433 tons, 6.1 %
    - Torpedo bulkhead: 0 tons, 0.0 %
    - Armament: 101 tons, 1.4 %
    - Armour Deck: 360 tons, 5.1 %
    - Conning Tower: 32 tons, 0.4 %
 Machinery: 2,347 tons, 33.3 %
 Hull, fittings & equipment: 3,010 tons, 42.7 %
 Fuel, ammunition & stores: 652 tons, 9.2 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   6,955 lbs / 3,155 Kg = 64.4 x 6.0 " / 152 mm shells or 1.1 torpedoes
 Stability (Unstable if below 1.00): 1.27
 Metacentric height 3.1 ft / 1.0 m
 Roll period: 13.1 seconds
 Steadiness - As gun platform (Average = 50 %): 52 %
   - Recoil effect (Restricted arc if above 1.00): 0.28
 Seaboat quality  (Average = 1.00): 1.04

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.449
 Length to Beam Ratio: 10.09 : 1
 'Natural speed' for length: 23.56 kts
 Power going to wave formation at top speed: 60 %
 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:  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 tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 120.6 %
  - Above water (accommodation/working, high = better): 173.7 %
 Waterplane Area: 19,456 Square feet or 1,808 Square metres
 Displacement factor (Displacement / loading): 108 %
 Structure weight / hull surface area: 92 lbs/sq ft or 448 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.94
  - Longitudinal: 1.67
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

The secret to better performance, for underperforming ships, is light-weight machinery

The underperforming 1923 design can be improved by using light-weight machinery. The sad fact is that Springsharp does not allow for very light machinery. The Japanese light cruisers built in the 1920's had very light machinery, but that cannot be duplicated in Springsharp. At least, I cannot duplicate it simply by manipulating the date. I should be able to achieve SHP/ton of machinery of over 60. Instead, I was just limited to something on the order of 40 SHP/ton or so. I have been trying not to change the machinery date, but that is the only way to fix this design. My modified fast British light cruiser now becomes more interesting. I was able to increase the speed to 35 knots and increase the armour to 3.5in belt and turrets, with a 2in deck. This is the modified Springsharp report:

GB/CL/1923, Great Britain Light Cruiser laid down 1923 (Engine 1950)

Displacement:
 10,595 t light; 10,983 t standard; 11,650 t normal; 12,183 t full load

Dimensions: Length overall / water x beam x draught
 619.03 ft / 615.00 ft x 60.00 ft x 20.00 ft (normal load)
 188.68 m / 187.45 m x 18.29 m  x 6.10 m

Armament:
      6 - 8.00" / 203 mm guns (3x2 guns), 256.00lbs / 116.12kg shells, 1923 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, majority forward, 1 raised mount - superfiring
      4 - 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, all amidships
      24 - 1.57" / 40.0 mm guns (6x4 guns), 2.00lbs / 0.91kg shells, 1923 Model
   Breech loading guns in deck mounts 
   on side, evenly spread
 Weight of broadside 1,792 lbs / 813 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: 3.50" / 89 mm 560.00 ft / 170.69 m 15.00 ft / 4.57 m
 Ends: Unarmoured
   Main Belt covers 140 % of normal length

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 3.50" / 89 mm 2.00" / 51 mm  3.50" / 89 mm
 3rd: 1.00" / 25 mm       -         -

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

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 134,726 shp / 100,506 Kw = 35.00 kts
 Range 5,400nm at 15.00 kts
 Bunker at max displacement = 1,200 tons

Complement:
 559 - 728

Cost:
 £2.938 million / $11.753 million

Distribution of weights at normal displacement:
 Armament: 224 tons, 1.9 %
 Armour: 2,477 tons, 21.3 %
    - Belts: 1,164 tons, 10.0 %
    - Torpedo bulkhead: 0 tons, 0.0 %
    - Armament: 291 tons, 2.5 %
    - Armour Deck: 955 tons, 8.2 %
    - Conning Tower: 66 tons, 0.6 %
 Machinery: 3,223 tons, 27.7 %
 Hull, fittings & equipment: 4,671 tons, 40.1 %
 Fuel, ammunition & stores: 1,055 tons, 9.1 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   13,683 lbs / 6,206 Kg = 53.4 x 8.0 " / 203 mm shells or 1.5 torpedoes
 Stability (Unstable if below 1.00): 1.17
 Metacentric height 3.1 ft / 1.0 m
 Roll period: 14.3 seconds
 Steadiness - As gun platform (Average = 50 %): 53 %
   - Recoil effect (Restricted arc if above 1.00): 0.48
 Seaboat quality  (Average = 1.00): 1.06

Hull form characteristics:
 Hull has a flush deck
 Block coefficient: 0.553
 Length to Beam Ratio: 10.25 : 1
 'Natural speed' for length: 24.80 kts
 Power going to wave formation at top speed: 61 %
 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 %): 22.00 ft / 6.71 m
    - Mid (67 %):  22.00 ft / 6.71 m
    - Quarterdeck (15 %): 22.00 ft / 6.71 m
    - Stern:  22.00 ft / 6.71 m
    - Average freeboard: 22.56 ft / 6.88 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 104.9 %
  - Above water (accommodation/working, high = better): 179.0 %
 Waterplane Area: 25,813 Square feet or 2,398 Square metres
 Displacement factor (Displacement / loading): 109 %
 Structure weight / hull surface area: 106 lbs/sq ft or 519 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.94
  - Longitudinal: 1.68
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is adequate
 Room for accommodation and workspaces is excellent

I wanted a 35-knot British light cruiser for 1923

What I thought should be possible was a 35-knot British light cruiser to be laid down in 1923. If such a ship is possible, it seems that it would not be very capable, except for the speed. I settled for a 34-knot design that resembles the Aoba class, but is too large. I had to inflate the dimensions and displacement to achieve anything remotely satisfactory. This is the Springsharp report for this disappointing design (disappointing to me):

GB/CL/1923, Great Britain Light Cruiser laid down 1923

Displacement:
 11,257 t light; 11,664 t standard; 12,550 t normal; 13,259 t full load

Dimensions: Length overall / water x beam x draught
 619.03 ft / 615.00 ft x 60.00 ft x 20.00 ft (normal load)
 188.68 m / 187.45 m x 18.29 m  x 6.10 m

Armament:
      6 - 8.00" / 203 mm guns (3x2 guns), 256.00lbs / 116.12kg shells, 1923 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, majority forward, 1 raised mount - superfiring
      4 - 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, all amidships
      24 - 1.57" / 40.0 mm guns (6x4 guns), 2.00lbs / 0.91kg shells, 1923 Model
   Breech loading guns in deck mounts 
   on side, evenly spread
 Weight of broadside 1,792 lbs / 813 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: 3.00" / 76 mm 540.00 ft / 164.59 m 15.00 ft / 4.57 m
 Ends: Unarmoured
   Main Belt covers 135 % of normal length

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 3.00" / 76 mm 2.00" / 51 mm  3.00" / 76 mm
 3rd: 1.00" / 25 mm       -         -

   - Armour deck: 1.50" / 38 mm, Conning tower: 6.00" / 152 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 127,794 shp / 95,334 Kw = 34.00 kts
 Range 5,400nm at 15.00 kts
 Bunker at max displacement = 1,595 tons

Complement:
 592 - 770

Cost:
 £3.433 million / $13.731 million

Distribution of weights at normal displacement:
 Armament: 224 tons, 1.8 %
 Armour: 2,044 tons, 16.3 %
    - Belts: 970 tons, 7.7 %
    - Torpedo bulkhead: 0 tons, 0.0 %
    - Armament: 258 tons, 2.1 %
    - Armour Deck: 746 tons, 5.9 %
    - Conning Tower: 70 tons, 0.6 %
 Machinery: 4,271 tons, 34.0 %
 Hull, fittings & equipment: 4,719 tons, 37.6 %
 Fuel, ammunition & stores: 1,293 tons, 10.3 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   10,618 lbs / 4,816 Kg = 41.5 x 8.0 " / 203 mm shells or 1.2 torpedoes
 Stability (Unstable if below 1.00): 1.24
 Metacentric height 3.4 ft / 1.0 m
 Roll period: 13.6 seconds
 Steadiness - As gun platform (Average = 50 %): 55 %
   - Recoil effect (Restricted arc if above 1.00): 0.44
 Seaboat quality  (Average = 1.00): 1.09

Hull form characteristics:
 Hull has a flush deck
 Block coefficient: 0.595
 Length to Beam Ratio: 10.25 : 1
 'Natural speed' for length: 24.80 kts
 Power going to wave formation at top speed: 61 %
 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 %): 22.00 ft / 6.71 m
    - Mid (67 %):  22.00 ft / 6.71 m
    - Quarterdeck (15 %): 22.00 ft / 6.71 m
    - Stern:  22.00 ft / 6.71 m
    - Average freeboard: 22.56 ft / 6.88 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 124.2 %
  - Above water (accommodation/working, high = better): 176.0 %
 Waterplane Area: 26,867 Square feet or 2,496 Square metres
 Displacement factor (Displacement / loading): 101 %
 Structure weight / hull surface area: 105 lbs/sq ft or 511 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.95
  - Longitudinal: 1.57
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

A British 1916 light cruiser design

I am not that happy with the result, but I have a British light cruiser design for 1916. Again, a great deal of displacement seems to be needed to have adequate composite strength. Perhaps someone can point out the error of my ways. This is a 32-knot ship with 8-6in QF, 4-4in AA, and 8-21in TT (above water). The belt is 3in and the deck is 2in. This is the Springsharp report:

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

Displacement:
 8,680 t light; 8,964 t standard; 9,750 t normal; 10,378 t full load

Dimensions: Length overall / water x beam x draught
 571.82 ft / 570.00 ft x 56.00 ft x 18.00 ft (normal load)
 174.29 m / 173.74 m x 17.07 m  x 5.49 m

Armament:
      8 - 6.00" / 152 mm guns (4x2 guns), 108.00lbs / 48.99kg shells, 1916 Model
   Breech loading 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, 1916 Model
   Anti-aircraft guns in deck mounts with hoists
   on side, all amidships, all raised mounts - superfiring
      16 - 1.57" / 40.0 mm guns (1x16 guns), 2.00lbs / 0.91kg shells, 1916 Model
   Anti-aircraft guns in deck mount 
   on side
 Weight of broadside 1,024 lbs / 464 kg
 Shells per gun, main battery: 150
 8 - 21.0" / 533.4 mm above water torpedoes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 3.00" / 76 mm 410.00 ft / 124.97 m 12.00 ft / 3.66 m
 Ends: Unarmoured
   Main Belt covers 111 % of normal length
   Main belt does not fully cover magazines and engineering spaces

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

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

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 88,221 shp / 65,813 Kw = 32.00 kts
 Range 4,700nm at 15.00 kts
 Bunker at max displacement = 1,414 tons

Complement:
 489 - 637

Cost:
 £1.426 million / $5.704 million

Distribution of weights at normal displacement:
 Armament: 128 tons, 1.3 %
 Armour: 1,772 tons, 18.2 %
    - Belts: 607 tons, 6.2 %
    - Torpedo bulkhead: 0 tons, 0.0 %
    - Armament: 267 tons, 2.7 %
    - Armour Deck: 859 tons, 8.8 %
    - Conning Tower: 39 tons, 0.4 %
 Machinery: 3,287 tons, 33.7 %
 Hull, fittings & equipment: 3,493 tons, 35.8 %
 Fuel, ammunition & stores: 1,070 tons, 11.0 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   8,961 lbs / 4,065 Kg = 83.0 x 6.0 " / 152 mm shells or 1.2 torpedoes
 Stability (Unstable if below 1.00): 1.27
 Metacentric height 3.2 ft / 1.0 m
 Roll period: 13.1 seconds
 Steadiness - As gun platform (Average = 50 %): 51 %
   - Recoil effect (Restricted arc if above 1.00): 0.31
 Seaboat quality  (Average = 1.00): 1.02

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.594
 Length to Beam Ratio: 10.18 : 1
 'Natural speed' for length: 23.87 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:  26.00 ft / 7.92 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: 19.68 ft / 6.00 m
 Ship tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 119.6 %
  - Above water (accommodation/working, high = better): 148.0 %
 Waterplane Area: 23,214 Square feet or 2,157 Square metres
 Displacement factor (Displacement / loading): 104 %
 Structure weight / hull surface area: 94 lbs/sq ft or 459 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.97
  - Longitudinal: 1.25
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

A fast armoured cruiser for 1921

The natural thing was to see what a 1921 British armoured cruiser, in the same vein, would look like. I initially tried 9-10in guns as a main armament, but that seemed too light for the size. The armament is still light with 9-12in BLR, 16-5.5in QF, 6-4.7in AA, and 24-2pdr AA guns. The armour basis is still just 9in and the maximum speed is still 33 knots. The displacement is a rather large 35,700 tons normal to achieve moderate results. This is the Springsharp report:

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

Displacement:
       32,643 t light; 33,848 t standard; 35,700 t normal; 37,182 t full load

Dimensions: Length overall / water x beam x draught
       814.10 ft / 812.00 ft x 96.00 ft x 28.00 ft (normal load)
       248.14 m / 247.50 m x 29.26 m  x 8.53 m

Armament:
    9 - 12.00" / 305 mm guns (3x3 guns), 864.00lbs / 391.90kg shells, 1921 Model
         Breech loading guns in turrets (on barbettes)
         on centreline ends, majority forward, 1 raised mount - superfiring
    16 - 5.50" / 140 mm guns (8x2 guns), 83.19lbs / 37.73kg 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 with hoists
         on side, evenly spread, all raised mounts
    24 - 1.57" / 40.0 mm guns (6x4 guns), 2.00lbs / 0.91kg shells, 1921 Model
         Anti-aircraft guns in deck mounts
         on side, evenly spread
       Weight of broadside 9,466 lbs / 4,294 kg
       Shells per gun, main battery: 90

Armour:
 - Belts:              Width (max)     Length (avg)            Height (avg)
       Main:   9.00" / 229 mm  600.00 ft / 182.88 m    17.00 ft / 5.18 m
       Ends:   Unarmoured
         Main Belt covers 114 % of normal length

 - Torpedo Bulkhead:
               2.00" / 51 mm   600.00 ft / 182.88 m    27.00 ft / 8.23 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:    5.00" / 127 mm  5.00" / 127 mm          5.00" / 127 mm
       4th:    1.00" / 25 mm         -                       -

 - Armour deck: 4.00" / 102 mm, Conning tower: 9.00" / 229 mm

Machinery:
       Oil fired boilers, steam turbines,
       Geared drive, 4 shafts, 170,392 shp / 127,112 Kw = 33.00 kts
       Range 6,000nm at 15.00 kts
       Bunker at max displacement = 3,335 tons

Complement:
       1,298 - 1,688

Cost:
       £7.529 million / $30.116 million

Distribution of weights at normal displacement:
       Armament: 1,183 tons, 3.3 %
       Armour: 11,888 tons, 33.3 %
          - Belts: 3,808 tons, 10.7 %
          - Torpedo bulkhead: 1,199 tons, 3.4 %
          - Armament: 2,388 tons, 6.7 %
          - Armour Deck: 4,283 tons, 12.0 %
          - Conning Tower: 210 tons, 0.6 %
       Machinery: 5,867 tons, 16.4 %
       Hull, fittings & equipment: 13,705 tons, 38.4 %
       Fuel, ammunition & stores: 3,057 tons, 8.6 %
       Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
       Survivability (Non-critical penetrating hits needed to sink ship):
         50,934 lbs / 23,103 Kg = 59.0 x 12.0 " / 305 mm shells or 7.1 torpedoes
       Stability (Unstable if below 1.00): 1.18
       Metacentric height 6.4 ft / 1.9 m
       Roll period: 15.9 seconds
       Steadiness      - As gun platform (Average = 50 %): 51 %
                       - Recoil effect (Restricted arc if above 1.00): 0.45
       Seaboat quality  (Average = 1.00): 1.03

Hull form characteristics:
       Hull has a flush deck
         and transom stern
       Block coefficient: 0.572
       Length to Beam Ratio: 8.46 : 1
       'Natural speed' for length: 32.69 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: 0.00 ft / 0.00 m
       Freeboard (% = measuring location as a percentage of overall length):
          - Stem:              30.00 ft / 9.14 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: 23.56 ft / 7.18 m
       Ship tends to be wet forward

Ship space, strength and comments:
       Space   - Hull below water (magazines/engines, low = better): 99.3 %
               - Above water (accommodation/working, high = better): 195.3 %
       Waterplane Area: 57,873 Square feet or 5,377 Square metres
       Displacement factor (Displacement / loading): 108 %
       Structure weight / hull surface area: 171 lbs/sq ft or 835 Kg/sq metre
       Hull strength (Relative):
               - Cross-sectional: 0.99
               - Longitudinal: 1.06
               - Overall: 1.00
       Hull space for machinery, storage, compartmentation is adequate
       Room for accommodation and workspaces is excellent