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Thursday, June 30, 2005

This is about 50%, or so, larger than planned: Ger/CA/1915

The Ger/CA/1915 (or whatever the year was) fast armoured cruiser was originally planned to be just 14,000 tons (!). That was over optimistic by a good bit. The only way that the other might just possibly have worked would have been to have very high power output machinery. The basic idea was to have a 6in armour basis with 8-9.4in guns (25 ton) with a 419lb APC shot. The secondary armament was 106in guns (5.5 ton) with a 101 lb. shot. The armour deck was thick, being 4inches. I had actually wanted a lower splinter deck of 3in. which I omitted here, as it seemed too extreme, even for me. This is the Springsharp report:
Ger/CA/1915, Germany Armoured Cruiser laid down 1915 (Engine 1927)

Displacement:
 21,233 t light; 22,005 t standard; 23,500 t normal; 24,696 t full load

Dimensions: Length overall / water x beam x draught
 726.08 ft / 725.00 ft x 80.00 ft x 25.00 ft (normal load)
 221.31 m / 220.98 m x 24.38 m  x 7.62 m

Armament:
      8 - 9.40" / 239 mm guns (4x2 guns), 419.00lbs / 190.06kg shells, 1915 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 2 raised mounts - superfiring
      10 - 6.00" / 152 mm guns in single mounts, 101.00lbs / 45.81kg shells, 1915 Model
   Quick firing guns in deck mounts with hoists
   on side ends, evenly spread, 2 raised mounts - superfiring
 Weight of broadside 4,362 lbs / 1,979 kg
 Shells per gun, main battery: 120

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 6.00" / 152 mm 555.00 ft / 169.16 m 17.00 ft / 5.18 m
 Ends: Unarmoured
   Main Belt covers 118 % of normal length

   - Torpedo Bulkhead:
  1.00" / 25 mm 555.00 ft / 169.16 m 22.00 ft / 6.71 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 8.00" / 203 mm 4.00" / 102 mm  6.00" / 152 mm
 2nd: 2.00" / 51 mm       -         -

   - Armour deck: 4.00" / 102 mm, Conning tower: 6.00" / 152 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 156,174 shp / 116,506 Kw = 33.00 kts
 Range 6,500nm at 15.00 kts
 Bunker at max displacement = 2,691 tons

Complement:
 948 - 1,233

Cost:
 £2.757 million / $11.029 million

Distribution of weights at normal displacement:
 Armament: 550 tons, 2.3 %
 Armour: 6,910 tons, 29.4 %
    - Belts: 2,322 tons, 9.9 %
    - Torpedo bulkhead: 452 tons, 1.9 %
    - Armament: 985 tons, 4.2 %
    - Armour Deck: 3,044 tons, 13.0 %
    - Conning Tower: 106 tons, 0.5 %
 Machinery: 4,930 tons, 21.0 %
 Hull, fittings & equipment: 8,843 tons, 37.6 %
 Fuel, ammunition & stores: 2,267 tons, 9.6 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   34,067 lbs / 15,453 Kg = 82.0 x 9.4 " / 239 mm shells or 4.1 torpedoes
 Stability (Unstable if below 1.00): 1.17
 Metacentric height 4.8 ft / 1.5 m
 Roll period: 15.4 seconds
 Steadiness - As gun platform (Average = 50 %): 59 %
   - Recoil effect (Restricted arc if above 1.00): 0.52
 Seaboat quality  (Average = 1.00): 1.19

Hull form characteristics:
 Hull has raised forecastle, rise forward of midbreak
 Block coefficient: 0.567
 Length to Beam Ratio: 9.06 : 1
 'Natural speed' for length: 26.93 kts
 Power going to wave formation at top speed: 56 %
 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 %): 29.00 ft / 8.84 m (28.00 ft / 8.53 m aft of break)
    - Mid (73 %):  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: 26.20 ft / 7.99 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 115.2 %
  - Above water (accommodation/working, high = better): 219.2 %
 Waterplane Area: 41,138 Square feet or 3,822 Square metres
 Displacement factor (Displacement / loading): 111 %
 Structure weight / hull surface area: 139 lbs/sq ft or 677 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.96
  - Longitudinal: 1.34
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

To get a useful fast battleship version of the Super Lion, the displacement really balloons

I made another attempt at a fast battleship version of Admiral Fisher's Super Lion concept for a 30 knot capital ship with 10-15in guns. The way that I have structured the design, I had to let the displacement grow considerably. The dimensions became 812ft x 108ft x 33ft and the displacement was 45,875 tons. The armour basis was 13 inches. I did not use the "all-or-nothing" scheme, as it seems inappropriate. I also did not use the wide belt of uniform thickness that I usually like. This is the Springsharp report. I have been looking at my two alternative photos of the Super Lion and decided to try this again.
Super Lion-fast battleship version, Enter country Enter ship type laid down 1912 (Engine 1915)

Displacement:
 41,537 t light; 43,387 t standard; 45,875 t normal; 47,866 t full load

Dimensions: Length overall / water x beam x draught
 812.00 ft / 812.00 ft x 108.00 ft x 33.00 ft (normal load)
 247.50 m / 247.50 m x 32.92 m  x 10.06 m

Armament:
      10 - 15.00" / 381 mm guns (5x2 guns), 1,920.00lbs / 870.90kg shells, 1912 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, majority forward, 2 raised mounts - superfiring
      14 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1912 Model
   Breech loading guns in casemate mounts 
   on side, all amidships
   14 guns in hull casemates - Limited use in heavy seas
 Weight of broadside 20,712 lbs / 9,395 kg
 Shells per gun, main battery: 80

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 13.0" / 330 mm 580.00 ft / 176.78 m 9.00 ft / 2.74 m
 Ends: 6.00" / 152 mm 160.00 ft / 48.77 m 9.00 ft / 2.74 m
   72.00 ft / 21.95 m Unarmoured ends
 Upper: 8.00" / 203 mm 580.00 ft / 176.78 m 8.00 ft / 2.44 m
   Main Belt covers 110 % of normal length

   - Torpedo Bulkhead:
  2.00" / 51 mm 580.00 ft / 176.78 m 29.00 ft / 8.84 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: 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, 157,275 shp / 117,327 Kw = 30.00 kts
 Range 6,500nm at 14.00 kts
 Bunker at max displacement = 4,479 tons

Complement:
 1,566 - 2,037

Cost:
 £4.218 million / $16.874 million

Distribution of weights at normal displacement:
 Armament: 2,298 tons, 5.0 %
 Armour: 14,275 tons, 31.1 %
    - Belts: 4,740 tons, 10.3 %
    - Torpedo bulkhead: 1,245 tons, 2.7 %
    - Armament: 4,520 tons, 9.9 %
    - Armour Deck: 3,412 tons, 7.4 %
    - Conning Tower: 359 tons, 0.8 %
 Machinery: 5,957 tons, 13.0 %
 Hull, fittings & equipment: 19,006 tons, 41.4 %
 Fuel, ammunition & stores: 4,338 tons, 9.5 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   61,238 lbs / 27,777 Kg = 36.3 x 15.0 " / 381 mm shells or 8.4 torpedoes
 Stability (Unstable if below 1.00): 1.07
 Metacentric height 6.4 ft / 1.9 m
 Roll period: 18.0 seconds
 Steadiness - As gun platform (Average = 50 %): 65 %
   - Recoil effect (Restricted arc if above 1.00): 0.89
 Seaboat quality  (Average = 1.00): 1.30

Hull form characteristics:
 Hull has a flush deck
 Block coefficient: 0.555
 Length to Beam Ratio: 7.52 : 1
 'Natural speed' for length: 28.50 kts
 Power going to wave formation at top speed: 51 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): -1.00 degrees
 Stern overhang: -1.00 ft / -0.30 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  33.00 ft / 10.06 m
    - Forecastle (20 %): 29.00 ft / 8.84 m
    - Mid (67 %):  29.00 ft / 8.84 m
    - Quarterdeck (15 %): 21.00 ft / 6.40 m
    - Stern:  21.00 ft / 6.40 m
    - Average freeboard: 27.40 ft / 8.35 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 98.0 %
  - Above water (accommodation/working, high = better): 208.6 %
 Waterplane Area: 61,479 Square feet or 5,712 Square metres
 Displacement factor (Displacement / loading): 103 %
 Structure weight / hull surface area: 213 lbs/sq ft or 1,038 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.96
  - Longitudinal: 1.44
  - 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 fast battleship design study: what I am calling the Ger/BB/1917

I did a fast battleship design study that for lack of another designation, I am calling the Ger/BB/1917 design study. The ship is 850ft x 850ft x 30.4ft. The speed is 30 knots. The armament is 9-18in/45 BLR with 20-5in QF guns. I used all the original specifications, except that the displacement ballooned from what I had overoptimistically hoped (50,000 tons) to 63,375 tons. This is the Springsharp report:
Ger/BB/1917 Design Study, Germany Enter ship type laid down 1917 (Engine 1937)

Displacement:
 57,751 t light; 60,366 t standard; 63,375 t normal; 65,783 t full load

Dimensions: Length overall / water x beam x draught
 851.78 ft / 850.00 ft x 120.00 ft x 30.40 ft (normal load)
 259.62 m / 259.08 m x 36.58 m  x 9.27 m

Armament:
      9 - 18.00" / 457 mm guns (3x3 guns), 3,200.00lbs / 1,451.50kg shells, 1917 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, majority forward, 1 raised mount - superfiring
      20 - 5.00" / 127 mm guns (10x2 guns), 62.50lbs / 28.35kg shells, 1917 Model
   Quick firing guns in deck mounts with hoists
   on side, all amidships, 4 raised mounts - superfiring
 Weight of broadside 30,050 lbs / 13,630 kg
 Shells per gun, main battery: 80

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 18.0" / 457 mm 555.00 ft / 169.16 m 8.00 ft / 2.44 m
 Ends: Unarmoured
 Upper: 16.0" / 406 mm 555.00 ft / 169.16 m 8.00 ft / 2.44 m
   Main Belt covers 100 % of normal length

   - Torpedo Bulkhead:
  2.00" / 51 mm 555.00 ft / 169.16 m 28.00 ft / 8.53 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 12.0" / 305 mm 8.00" / 203 mm  16.0" / 406 mm

   - Armour deck: 7.00" / 178 mm, Conning tower: 16.00" / 406 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 205,655 shp / 153,419 Kw = 30.00 kts
 Range 7,500nm at 15.00 kts
 Bunker at max displacement = 5,417 tons

Complement:
 1,996 - 2,596

Cost:
 £10.375 million / $41.499 million

Distribution of weights at normal displacement:
 Armament: 3,437 tons, 5.4 %
 Armour: 23,414 tons, 36.9 %
    - Belts: 6,568 tons, 10.4 %
    - Torpedo bulkhead: 1,150 tons, 1.8 %
    - Armament: 4,416 tons, 7.0 %
    - Armour Deck: 10,733 tons, 16.9 %
    - Conning Tower: 548 tons, 0.9 %
 Machinery: 5,700 tons, 9.0 %
 Hull, fittings & equipment: 25,201 tons, 39.8 %
 Fuel, ammunition & stores: 5,624 tons, 8.9 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   94,081 lbs / 42,675 Kg = 32.3 x 18.0 " / 457 mm shells or 13.7 torpedoes
 Stability (Unstable if below 1.00): 1.16
 Metacentric height 8.7 ft / 2.6 m
 Roll period: 17.1 seconds
 Steadiness - As gun platform (Average = 50 %): 52 %
   - Recoil effect (Restricted arc if above 1.00): 0.66
 Seaboat quality  (Average = 1.00): 1.03

Hull form characteristics:
 Hull has a flush deck
 Block coefficient: 0.715
 Length to Beam Ratio: 7.08 : 1
 'Natural speed' for length: 29.15 kts
 Power going to wave formation at top speed: 53 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 3.00 degrees
 Stern overhang: -2.00 ft / -0.61 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  34.00 ft / 10.36 m
    - Forecastle (20 %): 25.00 ft / 7.62 m
    - Mid (50 %):  25.00 ft / 7.62 m
    - Quarterdeck (15 %): 25.00 ft / 7.62 m
    - Stern:  25.00 ft / 7.62 m
    - Average freeboard: 25.72 ft / 7.84 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 84.0 %
  - Above water (accommodation/working, high = better): 197.7 %
 Waterplane Area: 82,877 Square feet or 7,699 Square metres
 Displacement factor (Displacement / loading): 102 %
 Structure weight / hull surface area: 232 lbs/sq ft or 1,132 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.98
  - Longitudinal: 1.18
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is adequate
 Room for accommodation and workspaces is excellent

Wednesday, June 29, 2005

Another try at the Ger/CB/1906 battlecruiser design

I just tried the Ger/CB/1906 battlecruiser design in SpringSharp. The ship is 800ft x 85ft x 26ft and the displacement rose from 25,000 tons to a much larger 27,050 tons. That was necessitated by structural strength demands. The armament is 8-12in/45 BLR and 8-6in/50 QF guns. The armour basis is 4in, but the deck armour is a substantial 3in. I did use higher output machinery than we might have used previously. The original design, however, was for at least 25 SHP/ton of machinery. That was for a 25,000 ton ship. This design uses 31.7 SHP/ton. This is the SpringSharp report:
Ger/CB/1906, Germany Battlecruiser laid down 1906 (Engine 1927)

Displacement:
 24,514 t light; 25,407 t standard; 27,050 t normal; 28,364 t full load

Dimensions: Length overall / water x beam x draught
 800.00 ft / 800.00 ft x 85.00 ft x 26.00 ft (normal load)
 243.84 m / 243.84 m x 25.91 m  x 7.92 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, 2 raised mounts - superfiring
      8 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1906 Model
   Quick firing guns in deck mounts with hoists
   on side ends, evenly spread
 Weight of broadside 7,776 lbs / 3,527 kg
 Shells per gun, main battery: 80

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 4.00" / 102 mm 610.00 ft / 185.93 m 16.00 ft / 4.88 m
 Ends: Unarmoured
   Main Belt covers 117 % of normal length

   - Torpedo Bulkhead:
  1.50" / 38 mm 610.00 ft / 185.93 m 24.00 ft / 7.32 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 8.00" / 203 mm 5.00" / 127 mm  6.00" / 152 mm
 2nd: 2.00" / 51 mm       -         -

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

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 160,914 shp / 120,042 Kw = 33.00 kts
 Range 6,500nm at 15.00 kts
 Bunker at max displacement = 2,957 tons

Complement:
 1,054 - 1,371

Cost:
 £2.386 million / $9.542 million

Distribution of weights at normal displacement:
 Armament: 972 tons, 3.6 %
 Armour: 6,568 tons, 24.3 %
    - Belts: 1,596 tons, 5.9 %
    - Torpedo bulkhead: 813 tons, 3.0 %
    - Armament: 1,406 tons, 5.2 %
    - Armour Deck: 2,598 tons, 9.6 %
    - Conning Tower: 155 tons, 0.6 %
 Machinery: 5,079 tons, 18.8 %
 Hull, fittings & equipment: 11,894 tons, 44.0 %
 Fuel, ammunition & stores: 2,536 tons, 9.4 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   38,765 lbs / 17,584 Kg = 44.9 x 12.0 " / 305 mm shells or 4.7 torpedoes
 Stability (Unstable if below 1.00): 1.10
 Metacentric height 4.7 ft / 1.4 m
 Roll period: 16.4 seconds
 Steadiness - As gun platform (Average = 50 %): 67 %
   - Recoil effect (Restricted arc if above 1.00): 0.87
 Seaboat quality  (Average = 1.00): 1.34

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.535
 Length to Beam Ratio: 9.41 : 1
 'Natural speed' for length: 28.28 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:  33.00 ft / 10.06 m
    - Forecastle (20 %): 30.00 ft / 9.14 m
    - Mid (71 %):  30.00 ft / 9.14 m (22.00 ft / 6.71 m aft of break)
    - Quarterdeck (15 %): 22.00 ft / 6.71 m
    - Stern:  22.00 ft / 6.71 m
    - Average freeboard: 27.92 ft / 8.51 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 115.0 %
  - Above water (accommodation/working, high = better): 239.2 %
 Waterplane Area: 46,817 Square feet or 4,349 Square metres
 Displacement factor (Displacement / loading): 110 %
 Structure weight / hull surface area: 163 lbs/sq ft or 797 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.97
  - Longitudinal: 1.35
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent
 Good seaboat, rides out heavy weather easily

A German version of the fast armoured cruiser: Ger/CA/1917

There is a pencil sketch that is clearly meant to be a German ship. This is a 729ft x 80ft x 25ft ship that grew to 23,500 tons. The speed that was practical was 35 knots, and this was possible with 6-11in and 8-6in guns with a 6 inch armour basis. A 36 knot speed would have meant an even larger displacement. This is probably a better bargain than a ship such as the Ger/CBL/1915 Mod.A with only 2-12in guns and a 4 inch armour basis, even with a speed of 40 knots. This is the SpringSharp report:
Ger/CA/1917 (in the F/CA/1921 style), Germany Armoured Cruiser laid down 1917 (Engine 1937) Displacement: 21,221 t light; 21,941 t standard; 23,500 t normal; 24,747 t full load Dimensions: Length overall / water x beam x draught 730.68 ft / 729.00 ft x 80.00 ft x 25.00 ft (normal load) 222.71 m / 222.20 m x 24.38 m x 7.62 m Armament: 6 - 11.00" / 279 mm guns (2x3 guns), 665.50lbs / 301.87kg shells, 1917 Model Breech loading guns in turrets (on barbettes) on centreline, all forward, 1 raised mount - superfiring 8 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1917 Model Quick firing guns in deck mounts with hoists on side, all amidships Weight of broadside 4,857 lbs / 2,203 kg Shells per gun, main battery: 90 Armour: - Belts: Width (max) Length (avg) Height (avg) Main: 6.00" / 152 mm 630.00 ft / 192.02 m 16.00 ft / 4.88 m Ends: Unarmoured Main Belt covers 133 % of normal length - Torpedo Bulkhead: 1.00" / 25 mm 630.00 ft / 192.02 m 23.00 ft / 7.01 m - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max) Main: 8.00" / 203 mm 5.00" / 127 mm 6.00" / 152 mm 2nd: 2.00" / 51 mm - - - Armour deck: 2.00" / 51 mm, Conning tower: 8.00" / 203 mm Machinery: Oil fired boilers, steam turbines, Geared drive, 4 shafts, 197,593 shp / 147,405 Kw = 35.00 kts Range 7,500nm at 15.00 kts Bunker at max displacement = 2,806 tons Complement: 948 - 1,233 Cost: £3.672 million / $14.687 million Distribution of weights at normal displacement: Armament: 607 tons, 2.6 % Armour: 5,527 tons, 23.5 % - Belts: 2,430 tons, 10.3 % - Torpedo bulkhead: 536 tons, 2.3 % - Armament: 893 tons, 3.8 % - Armour Deck: 1,526 tons, 6.5 % - Conning Tower: 141 tons, 0.6 % Machinery: 5,477 tons, 23.3 % Hull, fittings & equipment: 9,610 tons, 40.9 % Fuel, ammunition & stores: 2,279 tons, 9.7 % Miscellaneous weights: 0 tons, 0.0 % Overall survivability and seakeeping ability: Survivability (Non-critical penetrating hits needed to sink ship): 31,637 lbs / 14,350 Kg = 47.5 x 11.0 " / 279 mm shells or 3.6 torpedoes Stability (Unstable if below 1.00): 1.16 Metacentric height 4.7 ft / 1.4 m Roll period: 15.5 seconds Steadiness - As gun platform (Average = 50 %): 57 % - Recoil effect (Restricted arc if above 1.00): 0.59 Seaboat quality (Average = 1.00): 1.13 Hull form characteristics: Hull has rise forward of midbreak Block coefficient: 0.564 Length to Beam Ratio: 9.11 : 1 'Natural speed' for length: 27.00 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: 32.00 ft / 9.75 m - Forecastle (20 %): 30.00 ft / 9.14 m - Mid (67 %): 30.00 ft / 9.14 m (22.00 ft / 6.71 m aft of break) - Quarterdeck (15 %): 22.00 ft / 6.71 m - Stern: 22.00 ft / 6.71 m - Average freeboard: 27.52 ft / 8.39 m Ship space, strength and comments: Space - Hull below water (magazines/engines, low = better): 127.0 % - Above water (accommodation/working, high = better): 230.2 % Waterplane Area: 41,244 Square feet or 3,832 Square metres Displacement factor (Displacement / loading): 110 % Structure weight / hull surface area: 147 lbs/sq ft or 717 Kg/sq metre Hull strength (Relative): - Cross-sectional: 0.94 - Longitudinal: 1.63 - Overall: 1.00 Hull space for machinery, storage, compartmentation is cramped Room for accommodation and workspaces is excellent

Tuesday, June 28, 2005

A "better" version of the Ger/CBL/1915 Mod.A design

I wanted to have full coverage of armour over the machinery spaces and to have a 16ft wide belt. I was able to do that and still make 40 knots by using very high power output machinery. The machinery will produce 41.85 SHP/ton of machinery weight. While that is large, realize that HMS Swift, designed in 1905, could produce 50,000 SHP at about 60 SHP/ton. This is the revised Springsharp report:
Ger/CBL/1915 Mod.A, Germany Light Battlecruiser laid down 1915 (Engine 1950)

Displacement:
 20,566 t light; 21,141 t standard; 22,000 t normal; 22,687 t full load

Dimensions: Length overall / water x beam x draught
 801.78 ft / 800.00 ft x 80.00 ft x 25.00 ft (normal load)
 244.38 m / 243.84 m x 24.38 m  x 7.62 m

Armament:
      2 - 12.00" / 305 mm guns (1x2 guns), 864.00lbs / 391.90kg shells, 1915 Model
   Breech loading guns in a turret (on a barbette)
   on centreline forward
      12 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1915 Model
   Quick firing guns in deck mounts with hoists
   on side, all amidships
 Weight of broadside 3,024 lbs / 1,372 kg
 Shells per gun, main battery: 75

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 4.00" / 102 mm 620.00 ft / 188.98 m 16.00 ft / 4.88 m
 Ends: Unarmoured
   Main Belt covers 119 % of normal length

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 6.00" / 152 mm 4.00" / 102 mm  5.00" / 127 mm
 2nd: 2.00" / 51 mm       -         -

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

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 6 shafts, 297,389 shp / 221,853 Kw = 40.00 kts
 Range 4,500nm at 15.00 kts
 Bunker at max displacement = 1,546 tons

Complement:
 903 - 1,174

Cost:
 £2.958 million / $11.831 million

Distribution of weights at normal displacement:
 Armament: 378 tons, 1.7 %
 Armour: 3,620 tons, 16.5 %
    - Belts: 1,607 tons, 7.3 %
    - Torpedo bulkhead: 0 tons, 0.0 %
    - Armament: 360 tons, 1.6 %
    - Armour Deck: 1,551 tons, 7.1 %
    - Conning Tower: 101 tons, 0.5 %
 Machinery: 7,115 tons, 32.3 %
 Hull, fittings & equipment: 9,454 tons, 43.0 %
 Fuel, ammunition & stores: 1,434 tons, 6.5 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   22,462 lbs / 10,189 Kg = 26.0 x 12.0 " / 305 mm shells or 1.9 torpedoes
 Stability (Unstable if below 1.00): 1.25
 Metacentric height 5.4 ft / 1.6 m
 Roll period: 14.5 seconds
 Steadiness - As gun platform (Average = 50 %): 55 %
   - Recoil effect (Restricted arc if above 1.00): 0.31
 Seaboat quality  (Average = 1.00): 1.11

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.481
 Length to Beam Ratio: 10.00 : 1
 'Natural speed' for length: 28.28 kts
 Power going to wave formation at top speed: 60 %
 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:  34.00 ft / 10.36 m
    - Forecastle (20 %): 30.00 ft / 9.14 m
    - Mid (69 %):  30.00 ft / 9.14 m (22.00 ft / 6.71 m aft of break)
    - Quarterdeck (15 %): 22.00 ft / 6.71 m
    - Stern:  22.00 ft / 6.71 m
    - Average freeboard: 27.84 ft / 8.49 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 117.7 %
  - Above water (accommodation/working, high = better): 247.9 %
 Waterplane Area: 41,929 Square feet or 3,895 Square metres
 Displacement factor (Displacement / loading): 105 %
 Structure weight / hull surface area: 138 lbs/sq ft or 675 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

The latest attempt at the GB/CA/1912 design worked well

I just tried redesigning the GB/CA/1912 fast armoured cruiser design in Springsharp, and the result works quite well. This is inspired by my design efforts in the mid-1970's for alternative fast armoured cruiser designs that would have been built instead of battlecruisers. This version only uses technology appropriate to the date. This is a 650ft ship with 12-9.2in BLR and 12-6in QF guns. The armour basis is 6 inches. This is the Springsharp report:
GB/CA/1912, Great Britain Armoured Cruiser laid down 1912

Displacement:
 18,576 t light; 19,327 t standard; 20,684 t normal; 21,769 t full load

Dimensions: Length overall / water x beam x draught
 650.00 ft / 650.00 ft x 75.00 ft x 27.00 ft (normal load)
 198.12 m / 198.12 m x 22.86 m  x 8.23 m

Armament:
      12 - 9.20" / 234 mm guns (6x2 guns), 380.00lbs / 172.37kg shells, 1912 Model
   Breech loading guns in turrets (on barbettes)
   on centreline, evenly spread, 3 raised mounts
      12 - 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
   12 guns in hull casemates - Limited use in heavy seas
 Weight of broadside 5,856 lbs / 2,656 kg
 Shells per gun, main battery: 100

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 6.00" / 152 mm 450.00 ft / 137.16 m 17.00 ft / 5.18 m
 Ends: 4.00" / 102 mm 200.00 ft / 60.96 m 17.00 ft / 5.18 m
   Main Belt covers 107 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.00" / 25 mm 450.00 ft / 137.16 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: 4.00" / 102 mm 4.00" / 102 mm  4.00" / 102 mm

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

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 102,247 shp / 76,276 Kw = 30.00 kts
 Range 7,200nm at 12.00 kts
 Bunker at max displacement = 2,442 tons

Complement:
 862 - 1,121

Cost:
 £1.848 million / $7.390 million

Distribution of weights at normal displacement:
 Armament: 746 tons, 3.6 %
 Armour: 5,722 tons, 27.7 %
    - Belts: 2,423 tons, 11.7 %
    - Torpedo bulkhead: 383 tons, 1.9 %
    - Armament: 1,561 tons, 7.5 %
    - Armour Deck: 1,259 tons, 6.1 %
    - Conning Tower: 97 tons, 0.5 %
 Machinery: 4,077 tons, 19.7 %
 Hull, fittings & equipment: 8,031 tons, 38.8 %
 Fuel, ammunition & stores: 2,108 tons, 10.2 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   26,091 lbs / 11,835 Kg = 67.0 x 9.2 " / 234 mm shells or 3.2 torpedoes
 Stability (Unstable if below 1.00): 1.05
 Metacentric height 3.6 ft / 1.1 m
 Roll period: 16.6 seconds
 Steadiness - As gun platform (Average = 50 %): 67 %
   - Recoil effect (Restricted arc if above 1.00): 0.93
 Seaboat quality  (Average = 1.00): 1.33

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.550
 Length to Beam Ratio: 8.67 : 1
 'Natural speed' for length: 25.50 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:  32.00 ft / 9.75 m
    - Forecastle (20 %): 30.00 ft / 9.14 m
    - Mid (57 %):  30.00 ft / 9.14 m (22.00 ft / 6.71 m aft of break)
    - Quarterdeck (15 %): 22.00 ft / 6.71 m
    - Stern:  22.00 ft / 6.71 m
    - Average freeboard: 26.72 ft / 8.14 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 124.5 %
  - Above water (accommodation/working, high = better): 199.6 %
 Waterplane Area: 34,022 Square feet or 3,161 Square metres
 Displacement factor (Displacement / loading): 104 %
 Structure weight / hull surface area: 141 lbs/sq ft or 687 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.94
  - Longitudinal: 1.76
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent
 Good seaboat, rides out heavy weather easily

A 1915 German scout cruiser design: Ger/CS/1915

This is based on a pencil drawing with minimal specifications from about 1971 or 1972. This is a small, fast scout cruiser in the spirit of the Ger/CS/1905 and Ger/CS/1909 designs. This one is modest in its speed (34 knots), so that the other characteristics (seakeeping and hull strength) will benefit. The dimensions are 415ft x 42ft x 12ft. The displacement is 2,450 tons with a prismatic coefficient of 0.6 and a midship coefficient of 0.85. The armament is 4-6in QF guns and 4-21in TT. The ship has a raised forecastle and two stacks with a 6in gun between them. This is the Springsharp report:
Ger/CS/1915, Germany Scout Cruiser laid down 1915 (Engine 1927)

Displacement:
 2,125 t light; 2,207 t standard; 2,450 t normal; 2,644 t full load

Dimensions: Length overall / water x beam x draught
 416.84 ft / 415.00 ft x 42.00 ft x 12.00 ft (normal load)
 127.05 m / 126.49 m x 12.80 m  x 3.66 m

Armament:
      4 - 6.00" / 152 mm guns in single mounts, 100.00lbs / 45.36kg shells, 1915 Model
   Quick firing guns in deck mounts with hoists
   on centreline, evenly spread
   Aft Main mounts separated by engine room
 Weight of broadside 400 lbs / 181 kg
 Shells per gun, main battery: 150
 4 - 21.0" / 533.4 mm above water torpedoes

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 2 shafts, 50,789 shp / 37,888 Kw = 34.00 kts
 Range 4,200nm at 15.00 kts
 Bunker at max displacement = 437 tons

Complement:
 173 - 226

Cost:
 £0.441 million / $1.764 million

Distribution of weights at normal displacement:
 Armament: 54 tons, 2.2 %
 Machinery: 1,310 tons, 53.5 %
 Hull, fittings & equipment: 760 tons, 31.0 %
 Fuel, ammunition & stores: 325 tons, 13.3 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   699 lbs / 317 Kg = 6.5 x 6.0 " / 152 mm shells or 0.3 torpedoes
 Stability (Unstable if below 1.00): 1.54
 Metacentric height 2.8 ft / 0.9 m
 Roll period: 10.5 seconds
 Steadiness - As gun platform (Average = 50 %): 55 %
   - Recoil effect (Restricted arc if above 1.00): 0.26
 Seaboat quality  (Average = 1.00): 1.09

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.410
 Length to Beam Ratio: 9.88 : 1
 'Natural speed' for length: 20.37 kts
 Power going to wave formation at top speed: 64 %
 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:  24.00 ft / 7.32 m
    - Forecastle (20 %): 22.00 ft / 6.71 m
    - Mid (32 %):  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: 16.72 ft / 5.10 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 189.3 %
  - Above water (accommodation/working, high = better): 154.8 %
 Waterplane Area: 10,794 Square feet or 1,003 Square metres
 Displacement factor (Displacement / loading): 67 %
 Structure weight / hull surface area: 40 lbs/sq ft or 194 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.50
  - Longitudinal: 1.45
  - Overall: 0.56
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

Monday, June 27, 2005

I am doing a new version of my program to just do powercurve calculations

I am doing some Springsharp work for a friend, and I thought it time that I updated my program for doing just power curve calculations. It seemed like a good idea to be able to compare that with what Springsharp produces. I removed all the other calculations from this version. A requirement for this version is to be able to work with hull forms that have bulges that extend beyond the waterline beam measurement. I am still getting used to the idea that a midship coefficient can be greater than 1.0, but it is true. I had led a sheltered life and only read more general books. I have probably already mentioned this, but I used to think that a midship coefficient was always less than 1.0 and that the box for which the coefficients are calculated would be bounded by the maximum beam, at or below the waterline. That way, you would multiply the displacement in tons by 35 cubic feet per ton of seawater. That gives a volume. Divide that by the length, maximum beam, the prismatic coefficient, and the midship coefficient, and you have the calculated draft. In the new age calculation, with a midship coefficient that is potentially greater than 1.0, then things seem not to be that simple.

Another 1915 German battleship study

In our progress through the "Red Book" (that is what we are traversing in our presentation of designs), we have reached a design study for a German battleship, supposedly circa 1915, that had 12-16.5in BLR and 12-6in QF guns. The size was nominally 60,000 tons, but Springsharp required a greater displacement to achieve adequate hull strength. The dimensions were 920ft x 120ft x 34ft. The intended weights were:
  • Hull: 21,020 tons
  • Machinery: 6,700 tons
  • Armament: 3,810 tons
  • Protection: 23,670 tons
  • Miscellaneous: 4,800 tons
The Springsharp weights were:
  • Hull: 27,013 tons
  • Machinery: 6,092 tons
  • Armament: 3,585 tons
  • Protection: 22,118 tons
  • Fuel, ammunition and stores: 8,191 tons
Ger/BB/1915 60K 16.5in guns, Germany Battleship laid down 1915

Displacement:
 58,809 t light; 62,785 t standard; 67,000 t normal; 70,372 t full load

Dimensions: Length overall / water x beam x draught
 923.22 ft / 920.00 ft x 120.00 ft x 34.00 ft (normal load)
 281.40 m / 280.42 m x 36.58 m  x 10.36 m

Armament:
     12 - 16.50" / 419 mm guns (4x3 guns), 2,480.00lbs / 1,124.91kg shells, 1915 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, 2 raised mounts - superfiring
     16 - 6.00" / 152 mm guns (6 mounts), 100.00lbs / 45.36kg shells, 1915 Model
   Quick firing guns in turrets (on barbettes)
   on side, all amidships, 4 raised mounts - superfiring
 Weight of broadside 31,360 lbs / 14,225 kg
 Shells per gun, main battery: 150

Armour:
  - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 13.0" / 330 mm 620.00 ft / 188.98 m 17.00 ft / 5.18 m
 Ends: Unarmoured
   Main Belt covers 104 % of normal length

  - Torpedo Bulkhead:
  3.00" / 76 mm 620.00 ft / 188.98 m 32.00 ft / 9.75 m

  - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 15.0" / 381 mm 9.00" / 229 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: 13.00" / 330 mm

Machinery:
 Oil fired boilers, steam turbines,
 Geared drive, 4 shafts, 160,838 shp / 119,985 Kw = 28.50 kts
 Range 7,500nm at 15.00 kts
 Bunker at max displacement = 7,588 tons

Complement:
 2,081 - 2,706

Cost:
 £8.615 million / $34.459 million

Distribution of weights at normal displacement:
 Armament: 3,585 tons, 5.4 %
 Armour: 22,118 tons, 33.0 %
    - Belts: 5,846 tons, 8.7 %
    - Torpedo bulkhead: 2,202 tons, 3.3 %
    - Armament: 5,965 tons, 8.9 %
    - Armour Deck: 7,643 tons, 11.4 %
    - Conning Tower: 462 tons, 0.7 %
 Machinery: 6,092 tons, 9.1 %
 Hull, fittings & equipment: 27,013 tons, 40.3 %
 Fuel, ammunition & stores: 8,191 tons, 12.2 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   92,334 lbs / 41,882 Kg = 41.1 x 16.5 " / 419 mm shells or 14.6 torpedoes
 Stability (Unstable if below 1.00): 1.11
 Metacentric height 8.0 ft / 2.4 m
 Roll period: 17.8 seconds
 Steadiness - As gun platform (Average = 50 %): 66 %
   - Recoil effect (Restricted arc if above 1.00): 0.82
 Seaboat quality  (Average = 1.00): 1.33

Hull form characteristics:
 Hull has a flush deck
 Block coefficient: 0.625
 Length to Beam Ratio: 7.67 : 1
 'Natural speed' for length: 30.33 kts
 Power going to wave formation at top speed: 46 %
 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:  35.00 ft / 10.67 m
    - Forecastle (20 %): 25.00 ft / 7.62 m
    - Mid (50 %):  25.00 ft / 7.62 m
    - Quarterdeck (15 %): 25.00 ft / 7.62 m
    - Stern:  25.00 ft / 7.62 m
    - Average freeboard: 25.80 ft / 7.86 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 86.1 %
  - Above water (accommodation/working, high = better): 189.1 %
 Waterplane Area: 82,625 Square feet or 7,676 Square metres
 Displacement factor (Displacement / loading): 106 %
 Structure weight / hull surface area: 240 lbs/sq ft or 1,171 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.99
  - Longitudinal: 1.10
  - 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

An improved Ger?CS/1905 photo

This improves the shading and restores some detail to the photo for my Ger/CS/1905 scout cruiser. This also has the improved perspective. This is the ship that is 370ft long and was intended to have a 36 knot speed. The armament was 4-4in QF guns and 2-18in TT. There was to be a patch 0f 2in armour over the machinery spaces.

While I was attempting to copy and paste the URL for the photo, the combination of Firefox and Blogger was misbehaving. I had to paste the URL for the photo to Notepad and then I could copy and paste to Blogger in Firefox.

Sunday, June 26, 2005

A new attempt at the 16.5in gun armed German battleship

I have this design study for a German battleship, circa 1915, that I am calling the Ger/BB/1915, along with all the other variants. This ship has 9-16.5in guns (130 ton) and 10-6in guns (6 ton). The originally designed speed was 25 knots, but 120,000 SHP was allocated, and 26 knots is achievable with under 100,000 SHP. The normal displacement was intended to be 45,000 tons, and that works in Springsharp. The biggest problem was hull strength. I thought I had a problem with recoil, but this was because I had omitted the height of the anti-torpedo bulkhead. Once this was specified, then everything worked better. This is the Springsharp report:
Ger/BB/1915, Germany Battleship laid down 1915

Displacement:
 39,693 t light; 41,768 t standard; 45,000 t normal; 47,586 t full load

Dimensions: Length overall / water x beam x draught
 755.00 ft / 755.00 ft x 110.00 ft x 32.00 ft (normal load)
 230.12 m / 230.12 m x 33.53 m  x 9.75 m

Armament:
      9 - 16.50" / 419 mm guns (3x3 guns), 2,480.00lbs / 1,124.91kg shells, 1915 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, majority forward, 1 raised mount - superfiring
      10 - 6.00" / 152 mm guns in single mounts, 100.00lbs / 45.36kg shells, 1915 Model
   Quick firing guns in deck mounts with hoists
   on side, evenly spread, 2 raised mounts
 Weight of broadside 23,320 lbs / 10,578 kg
 Shells per gun, main battery: 90

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 13.0" / 330 mm 490.00 ft / 149.35 m 17.00 ft / 5.18 m
 Ends: 6.00" / 152 mm 100.00 ft / 30.48 m 8.00 ft / 2.44 m
   165.00 ft / 50.29 m Unarmoured ends
   Main Belt covers 100 % of normal length

   - Torpedo Bulkhead:
  2.00" / 51 mm 490.00 ft / 149.35 m 28.00 ft / 8.53 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: 2.00" / 51 mm       -         -

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

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 93,663 shp / 69,873 Kw = 26.00 kts
 Range 7,500nm at 15.00 kts
 Bunker at max displacement = 5,818 tons

Complement:
 1,544 - 2,008

Cost:
 £5.995 million / $23.982 million

Distribution of weights at normal displacement:
 Armament: 2,662 tons, 5.9 %
 Armour: 14,343 tons, 31.9 %
    - Belts: 4,880 tons, 10.8 %
    - Torpedo bulkhead: 1,015 tons, 2.3 %
    - Armament: 3,630 tons, 8.1 %
    - Armour Deck: 4,464 tons, 9.9 %
    - Conning Tower: 354 tons, 0.8 %
 Machinery: 3,548 tons, 7.9 %
 Hull, fittings & equipment: 19,140 tons, 42.5 %
 Fuel, ammunition & stores: 5,307 tons, 11.8 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   66,574 lbs / 30,197 Kg = 29.6 x 16.5 " / 419 mm shells or 10.0 torpedoes
 Stability (Unstable if below 1.00): 1.10
 Metacentric height 6.9 ft / 2.1 m
 Roll period: 17.6 seconds
 Steadiness - As gun platform (Average = 50 %): 75 %
   - Recoil effect (Restricted arc if above 1.00): 0.96
 Seaboat quality  (Average = 1.00): 1.50

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.593
 Length to Beam Ratio: 6.86 : 1
 'Natural speed' for length: 27.48 kts
 Power going to wave formation at top speed: 47 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): -2.00 degrees
 Stern overhang: -2.00 ft / -0.61 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  32.00 ft / 9.75 m
    - Forecastle (20 %): 28.00 ft / 8.53 m
    - Mid (67 %):  28.00 ft / 8.53 m (20.00 ft / 6.10 m aft of break)
    - Quarterdeck (15 %): 20.00 ft / 6.10 m
    - Stern:  20.00 ft / 6.10 m
    - Average freeboard: 25.68 ft / 7.83 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 86.0 %
  - Above water (accommodation/working, high = better): 191.9 %
 Waterplane Area: 60,325 Square feet or 5,604 Square metres
 Displacement factor (Displacement / loading): 105 %
 Structure weight / hull surface area: 226 lbs/sq ft or 1,105 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.95
  - Longitudinal: 1.62
  - Overall: 1.00
 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

The "Maximum" version of the French armoured cruiser

Typically, I underestimated the hull weight necessary to provide the needed strength for the F/CA/1921 armoured cruiser. For better or worse, I decreased the armour belt to 6 inches. The speed is also 35 knots, instead of faster. I wanted a greater range, so that, alone, drove up the displacement. Also, going to a 11in gun for the main armament increased the weight demands. The ship is what Frank Fox calls a "cruiser killer". This is the resulting Springsharp report:
F/CA/1921, France Armored Cruiser laid down 1921

Displacement:
 22,123 t light; 22,943 t standard; 24,350 t normal; 25,475 t full load

Dimensions: Length overall / water x beam x draught
 730.15 ft / 729.00 ft x 80.00 ft x 27.00 ft (normal load)
 222.55 m / 222.20 m x 24.38 m  x 8.23 m

Armament:
      6 - 11.00" / 279 mm guns (2x3 guns), 665.50lbs / 301.87kg shells, 1921 Model
   Breech loading guns in turrets (on barbettes)
   on centreline, all forward, 1 raised mount - superfiring
      8 - 6.00" / 152 mm guns (4x2 guns), 108.00lbs / 48.99kg shells, 1921 Model
   Quick firing guns in deck mounts with hoists
   on side, all aft
 Weight of broadside 4,857 lbs / 2,203 kg
 Shells per gun, main battery: 120
 6 - 21.0" / 533.4 mm above water torpedoes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 6.00" / 152 mm 510.00 ft / 155.45 m 8.00 ft / 2.44 m
 Ends: Unarmoured
   Main Belt covers 108 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.00" / 25 mm 510.00 ft / 155.45 m 22.00 ft / 6.71 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 8.00" / 203 mm 5.00" / 127 mm  6.00" / 152 mm
 2nd: 2.00" / 51 mm       -         -

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

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 199,394 shp / 148,748 Kw = 35.00 kts
 Range 5,600nm at 15.00 kts
 Bunker at max displacement = 2,532 tons

Complement:
 974 - 1,267

Cost:
 £5.716 million / $22.864 million

Distribution of weights at normal displacement:
 Armament: 607 tons, 2.5 %
 Armour: 4,702 tons, 19.3 %
    - Belts: 1,017 tons, 4.2 %
    - Torpedo bulkhead: 415 tons, 1.7 %
    - Armament: 885 tons, 3.6 %
    - Armour Deck: 2,240 tons, 9.2 %
    - Conning Tower: 145 tons, 0.6 %
 Machinery: 6,866 tons, 28.2 %
 Hull, fittings & equipment: 9,947 tons, 40.9 %
 Fuel, ammunition & stores: 2,227 tons, 9.1 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   25,267 lbs / 11,461 Kg = 38.0 x 11.0 " / 279 mm shells or 2.8 torpedoes
 Stability (Unstable if below 1.00): 1.15
 Metacentric height 4.7 ft / 1.4 m
 Roll period: 15.6 seconds
 Steadiness - As gun platform (Average = 50 %): 60 %
   - Recoil effect (Restricted arc if above 1.00): 0.63
 Seaboat quality  (Average = 1.00): 1.20

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.541
 Length to Beam Ratio: 9.11 : 1
 'Natural speed' for length: 27.00 kts
 Power going to wave formation at top speed: 59 %
 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:  33.00 ft / 10.06 m
    - Forecastle (20 %): 30.00 ft / 9.14 m
    - Mid (75 %):  30.00 ft / 9.14 m (22.00 ft / 6.71 m aft of break)
    - Quarterdeck (15 %): 22.00 ft / 6.71 m
    - Stern:  22.00 ft / 6.71 m
    - Average freeboard: 28.24 ft / 8.61 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 147.4 %
  - Above water (accommodation/working, high = better): 211.0 %
 Waterplane Area: 40,368 Square feet or 3,750 Square metres
 Displacement factor (Displacement / loading): 105 %
 Structure weight / hull surface area: 150 lbs/sq ft or 730 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.94
  - Longitudinal: 1.82
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent
 Good seaboat, rides out heavy weather easily

Saturday, June 25, 2005

The F/CA/1917 Fast photo

This is a pretty rough photo of a F/CA/1917 Fast armoured cruiser. It was scaled off the pencil drawing from circa 1971.

I had done a design study for fast French armoured cruisers

Back in the early 1970's, I had done a design study for very fast French armoured cruisers to be named:
  • Dunkerque
  • Strasbourg
  • Jean Bart
  • Richelieu
  • Gascogne
  • Clemenceau
I had designed a short version and then realized that for higher speed, the length needed to be expanded to 729ft from 676ft. The armament is 6-9.4in (25 ton) BLR and 8-4in QF guns. The above water torpedo armament is 6-21in TT. the armour belt is 8in, although it is just 8ft tall. This is the Springsharp report:
F/CA/1917 , France Armored Cruiser laid down 1917 (Engine 1950)

Displacement:
 17,729 t light; 18,302 t standard; 19,250 t normal; 20,009 t full load

Dimensions: Length overall / water x beam x draught
 730.15 ft / 729.00 ft x 75.00 ft x 27.00 ft (normal load)
 222.55 m / 222.20 m x 22.86 m  x 8.23 m

Armament:
      6 - 9.40" / 239 mm guns (2x3 guns), 415.29lbs / 188.37kg shells, 1917 Model
   Breech loading guns in turrets (on barbettes)
   on centreline, all forward, 1 raised mount - superfiring
      8 - 4.00" / 102 mm guns (4x2 guns), 32.00lbs / 14.51kg shells, 1917 Model
   Quick firing guns in deck mounts with hoists
   on side, all aft
 Weight of broadside 2,748 lbs / 1,246 kg
 Shells per gun, main battery: 120
 6 - 21.0" / 533.4 mm above water torpedoes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 8.00" / 203 mm 495.00 ft / 150.88 m 8.00 ft / 2.44 m
 Ends: Unarmoured
   Main Belt covers 104 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.00" / 25 mm 495.00 ft / 150.88 m 22.00 ft / 6.71 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 8.00" / 203 mm 5.00" / 127 mm  6.00" / 152 mm
 2nd: 2.00" / 51 mm       -         -

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

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 183,690 shp / 137,033 Kw = 36.00 kts
 Range 5,600nm at 15.00 kts
 Bunker at max displacement = 1,707 tons

Complement:
 816 - 1,062

Cost:
 £2.771 million / $11.086 million

Distribution of weights at normal displacement:
 Armament: 343 tons, 1.8 %
 Armour: 4,505 tons, 23.4 %
    - Belts: 1,310 tons, 6.8 %
    - Torpedo bulkhead: 403 tons, 2.1 %
    - Armament: 723 tons, 3.8 %
    - Armour Deck: 1,946 tons, 10.1 %
    - Conning Tower: 124 tons, 0.6 %
 Machinery: 4,395 tons, 22.8 %
 Hull, fittings & equipment: 8,487 tons, 44.1 %
 Fuel, ammunition & stores: 1,521 tons, 7.9 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   28,411 lbs / 12,887 Kg = 68.4 x 9.4 " / 239 mm shells or 3.4 torpedoes
 Stability (Unstable if below 1.00): 1.09
 Metacentric height 3.8 ft / 1.2 m
 Roll period: 16.1 seconds
 Steadiness - As gun platform (Average = 50 %): 72 %
   - Recoil effect (Restricted arc if above 1.00): 0.54
 Seaboat quality  (Average = 1.00): 1.44

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.456
 Length to Beam Ratio: 9.72 : 1
 'Natural speed' for length: 27.00 kts
 Power going to wave formation at top speed: 56 %
 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:  33.00 ft / 10.06 m
    - Forecastle (20 %): 30.00 ft / 9.14 m
    - Mid (75 %):  30.00 ft / 9.14 m (22.00 ft / 6.71 m aft of break)
    - Quarterdeck (15 %): 22.00 ft / 6.71 m
    - Stern:  22.00 ft / 6.71 m
    - Average freeboard: 28.24 ft / 8.61 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 120.2 %
  - Above water (accommodation/working, high = better): 217.6 %
 Waterplane Area: 35,060 Square feet or 3,257 Square metres
 Displacement factor (Displacement / loading): 120 %
 Structure weight / hull surface area: 136 lbs/sq ft or 663 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.92
  - Longitudinal: 2.18
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent
 Ship has slow, easy roll, a good, steady gun platform
 Good seaboat, rides out heavy weather easily

Photo of a Ger/CBL/1915 Mod.A fast, light battlecruiser (UPDATED)

This is my first attempt at a photo of a Ger/CBL/1915 Mod.A fast, light battlecruiser. It is 800ft x 80ft x 25ft, and 20,750 tons displacement. The armament is 2-12in/45 BLR and 12-6in/50 QF guns. The armor basis is 4in and the speed is 40 knots, in the fastest version. The updated version of this photo corrects the funnels being too tall, as well as the mainmast. This ship design is intended to be used in the anti-cruiser role. WWI-style light cruisers would be run down and destroyed with the two 12in guns. The side armor is thick enough to allow the ship to close with the smaller light cruisers and the 6-6in guns on the broadside are sufficient to engage them as the ship closes for the kill.

The Ger/BB/1916 Large is amazing to me

I just ran the Ger/BB/1916 Large design study through Springsharp, and was very pleased and amazed at how well it did. I must confess that I don't believe the result, but I had happy to see it. This was for a ship 1085ft x 140ft x 38ft, with 9-19.75in BLR and 24-5in QF guns. The armor basis is 19in. The speed is 31 knots. Great length makes this easily attainable, even with a 1916 machinery plant. This is the Springsharp report:
Ger/BB/1916 Large, Germany Battleship laid down 1916

Displacement:
 93,126 t light; 97,049 t standard; 105,000 t normal; 111,361 t full load

Dimensions: Length overall / water x beam x draught
 1,088.89 ft / 1,085.00 ft x 140.00 ft x 38.00 ft (normal load)
 331.89 m / 330.71 m x 42.67 m  x 11.58 m

Armament:
      9 - 19.75" / 502 mm guns (3x3 guns), 3,851.87lbs / 1,747.18kg shells, 1916 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, 1916 Model
   Quick firing guns in turrets (on barbettes)
   on side, all amidships, 4 raised mounts - superfiring
 Weight of broadside 36,167 lbs / 16,405 kg
 Shells per gun, main battery: 90

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 19.0" / 483 mm 705.00 ft / 214.88 m 17.00 ft / 5.18 m
 Ends: Unarmoured
   Main Belt covers 100 % of normal length

   - Torpedo Bulkhead:
  5.00" / 127 mm 705.00 ft / 214.88 m 36.00 ft / 10.97 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 19.0" / 483 mm 14.0" / 356 mm  19.0" / 483 mm
 2nd: 5.00" / 127 mm 5.00" / 127 mm  5.00" / 127 mm

   - Armour deck: 7.00" / 178 mm, Conning tower: 19.00" / 483 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 280,099 shp / 208,954 Kw = 31.00 kts
 Range 7,500nm at 18.00 kts
 Bunker at max displacement = 14,311 tons

Complement:
 2,916 - 3,791

Cost:
 £13.938 million / $55.754 million

Distribution of weights at normal displacement:
 Armament: 4,521 tons, 4.3 %
 Armour: 38,485 tons, 36.7 %
    - Belts: 9,778 tons, 9.3 %
    - Torpedo bulkhead: 4,695 tons, 4.5 %
    - Armament: 8,215 tons, 7.8 %
    - Armour Deck: 14,886 tons, 14.2 %
    - Conning Tower: 911 tons, 0.9 %
 Machinery: 10,436 tons, 9.9 %
 Hull, fittings & equipment: 39,684 tons, 37.8 %
 Fuel, ammunition & stores: 11,874 tons, 11.3 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   165,609 lbs / 75,119 Kg = 43.0 x 19.8 " / 502 mm shells or 32.3 torpedoes
 Stability (Unstable if below 1.00): 1.20
 Metacentric height 11.5 ft / 3.5 m
 Roll period: 17.3 seconds
 Steadiness - As gun platform (Average = 50 %): 67 %
   - Recoil effect (Restricted arc if above 1.00): 0.51
 Seaboat quality  (Average = 1.00): 1.33

Hull form characteristics:
 Hull has a flush deck
 Block coefficient: 0.637
 Length to Beam Ratio: 7.75 : 1
 'Natural speed' for length: 32.94 kts
 Power going to wave formation at top speed: 46 %
 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:  36.00 ft / 10.97 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: 28.64 ft / 8.73 m
 Ship tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 75.8 %
  - Above water (accommodation/working, high = better): 210.2 %
 Waterplane Area: 114,947 Square feet or 10,679 Square metres
 Displacement factor (Displacement / loading): 110 %
 Structure weight / hull surface area: 258 lbs/sq ft or 1,262 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 1.02
  - Longitudinal: 0.99
  - 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

Another look at the Ger/BB/1915 CDV

Back in 1971, we were very aware of the apparent uses of coast defense battleships. I had designed the Ger/BB/1915 CDV to be sort of a modern "pre-dreadnought". The original design was actually to conservative. The Springsharp design is actually more capable, although I suppose that part of the reason is that the protection is somewhat less than the original design weight of 14,970 tons. This is the Springsharp report:
Ger/BB/1915 CDV, Germany Coast Defense Battleship laid down 1915

Displacement:
 25,503 t light; 26,575 t standard; 28,000 t normal; 29,140 t full load

Dimensions: Length overall / water x beam x draught
 585.00 ft / 585.00 ft x 100.00 ft x 29.10 ft (normal load)
 178.31 m / 178.31 m x 30.48 m  x 8.87 m

Armament:
      4 - 18.00" / 457 mm guns (2x2 guns), 2,916.00lbs / 1,322.68kg shells, 1915 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread
      20 - 5.00" / 127 mm guns (10x2 guns), 62.50lbs / 28.35kg shells, 1915 Model
   Quick firing guns in turrets (on barbettes)
   on side, all amidships, 4 raised mounts - superfiring
 Weight of broadside 12,914 lbs / 5,858 kg
 Shells per gun, main battery: 70

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 12.0" / 305 mm 400.00 ft / 121.92 m 17.00 ft / 5.18 m
 Ends: Unarmoured
   Main Belt covers 105 % of normal length

   - Torpedo Bulkhead:
  3.00" / 76 mm 400.00 ft / 121.92 m 27.00 ft / 8.23 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 13.0" / 330 mm 8.00" / 203 mm  12.0" / 305 mm
 2nd: 3.00" / 76 mm 3.00" / 76 mm  3.00" / 76 mm

   - Armour deck: 4.00" / 102 mm, Conning tower: 12.00" / 305 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 66,211 shp / 49,393 Kw = 25.00 kts
 Range 4,250nm at 15.00 kts
 Bunker at max displacement = 2,565 tons

Complement:
 1,081 - 1,406

Cost:
 £3.781 million / $15.126 million

Distribution of weights at normal displacement:
 Armament: 1,614 tons, 5.8 %
 Armour: 10,282 tons, 36.7 %
    - Belts: 3,555 tons, 12.7 %
    - Torpedo bulkhead: 1,199 tons, 4.3 %
    - Armament: 2,194 tons, 7.8 %
    - Armour Deck: 3,095 tons, 11.1 %
    - Conning Tower: 238 tons, 0.9 %
 Machinery: 2,508 tons, 9.0 %
 Hull, fittings & equipment: 11,099 tons, 39.6 %
 Fuel, ammunition & stores: 2,497 tons, 8.9 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   40,419 lbs / 18,334 Kg = 13.9 x 18.0 " / 457 mm shells or 7.1 torpedoes
 Stability (Unstable if below 1.00): 1.15
 Metacentric height 6.5 ft / 2.0 m
 Roll period: 16.5 seconds
 Steadiness - As gun platform (Average = 50 %): 64 %
   - Recoil effect (Restricted arc if above 1.00): 0.58
 Seaboat quality  (Average = 1.00): 1.28

Hull form characteristics:
 Hull has a flush deck
 Block coefficient: 0.576
 Length to Beam Ratio: 5.85 : 1
 'Natural speed' for length: 24.19 kts
 Power going to wave formation at top speed: 54 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 0.00 degrees
 Stern overhang: -1.00 ft / -0.30 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 (50 %):  22.00 ft / 6.71 m
    - Quarterdeck (15 %): 22.00 ft / 6.71 m
    - Stern:  22.00 ft / 6.71 m
    - Average freeboard: 22.24 ft / 6.78 m
 Ship tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 89.9 %
  - Above water (accommodation/working, high = better): 162.1 %
 Waterplane Area: 41,822 Square feet or 3,885 Square metres
 Displacement factor (Displacement / loading): 99 %
 Structure weight / hull surface area: 191 lbs/sq ft or 930 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.92
  - Longitudinal: 2.07
  - 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

Friday, June 24, 2005

A 40-knot Ger/CBL/1915 Mod.A a2

This is the even faster version of the Ger/CBL/1915 Mod.A (a2) that can make 40 knots. The armor is reduced, for one thing, the draft and displacement were increased, as well. The seakeeping was improved by raising the freeboard and the strength was brought up to where it needed to be by the draft and displacement increases. The increased hull depth also helped. This is the Springsharp report:
Ger/CBL/1915 Mod.A a2, Great Britain Battlecruiser laid down 1915 (Engine 1950)

Displacement:
 19,372 t light; 19,922 t standard; 20,750 t normal; 21,412 t full load

Dimensions: Length overall / water x beam x draught
 803.19 ft / 800.00 ft x 80.00 ft x 25.00 ft (normal load)
 244.81 m / 243.84 m x 24.38 m  x 7.62 m

Armament:
      2 - 12.00" / 305 mm guns (1x2 guns), 864.00lbs / 391.90kg shells, 1915 Model
   Breech loading guns in a turret (on a barbette)
   on centreline forward
      12 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1915 Model
   Quick firing guns in deck mounts with hoists
   on side, all amidships
 Weight of broadside 3,024 lbs / 1,372 kg
 Shells per gun, main battery: 75

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 4.00" / 102 mm 620.00 ft / 188.98 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

   - Torpedo Bulkhead:
  1.00" / 25 mm 620.00 ft / 188.98 m 20.00 ft / 6.10 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 6.00" / 152 mm 4.00" / 102 mm  5.00" / 127 mm
 2nd: 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, 282,457 shp / 210,713 Kw = 40.00 kts
 Range 4,500nm at 15.00 kts
 Bunker at max displacement = 1,491 tons

Complement:
 863 - 1,123

Cost:
 £2.824 million / $11.296 million

Distribution of weights at normal displacement:
 Armament: 378 tons, 1.8 %
 Armour: 2,802 tons, 13.5 %
    - Belts: 1,203 tons, 5.8 %
    - Torpedo bulkhead: 459 tons, 2.2 %
    - Armament: 317 tons, 1.5 %
    - Armour Deck: 758 tons, 3.7 %
    - Conning Tower: 65 tons, 0.3 %
 Machinery: 6,757 tons, 32.6 %
 Hull, fittings & equipment: 9,435 tons, 45.5 %
 Fuel, ammunition & stores: 1,378 tons, 6.6 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   21,371 lbs / 9,694 Kg = 24.7 x 12.0 " / 305 mm shells or 2.4 torpedoes
 Stability (Unstable if below 1.00): 1.25
 Metacentric height 5.4 ft / 1.6 m
 Roll period: 14.5 seconds
 Steadiness - As gun platform (Average = 50 %): 60 %
   - Recoil effect (Restricted arc if above 1.00): 0.33
 Seaboat quality  (Average = 1.00): 1.20

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.454
 Length to Beam Ratio: 10.00 : 1
 'Natural speed' for length: 28.28 kts
 Power going to wave formation at top speed: 59 %
 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:  34.00 ft / 10.36 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: 28.60 ft / 8.72 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 158.9 %
  - Above water (accommodation/working, high = better): 260.2 %
 Waterplane Area: 40,955 Square feet or 3,805 Square metres
 Displacement factor (Displacement / loading): 107 %
 Structure weight / hull surface area: 138 lbs/sq ft or 674 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.94
  - Longitudinal: 1.69
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent
 Good seaboat, rides out heavy weather easily

I suspect that it is true the Admirlal Fisher actually wanted to use the light battlecruisers as well-armed light cruisers

I read that at one point, Admiral Fisher had praised the Courageous, Glorious, and Furious as being good light cruisers. They would be able to maintain their speed better than the small ships, and would have a potent offensive capability at short range. They were not suited for long-range engagements at sea, but they could be extremely deadly at pre-dreadnought ranges, where they would being firing directly at a close target. The British excelled at this sort of firing in the late pre-dreadnought period, especially after Percy Scott's improvements. The Ger/CBL/1915 Mod.A is this sort of ship. It is fast enough, at 37 knots, to catch smaller cruisers, especially in a seaway, and has enough protection with a 4in belt to be able to engage them at close range. If 40 knots were achievable, this type would be even more capable.

A really extreme design: Ger/CBL/1915 Mod.A

This is a design study that I did about 1971. It was for an extremely fast light battlecruiser. I had hoped for 40 knots, but 37 knots seems about all that is feasible. I'm still amazed that it does as well as it does. This sort of ship has a pre-Dreadnought flavor to it, due to having only two large caliber guns. You would think it was an 1880's design, except for the more modern configuration. It sacrifices armour and armament to achieve an extreme speed. This is the Springsharp report:
Ger/CBL/1915 Mod.A, Germany Light Battlecruiser laid down 1915 (Engine 1941)

Displacement:
 18,430 t light; 18,974 t standard; 20,000 t normal; 20,821 t full load

Dimensions: Length overall / water x beam x draught
 803.15 ft / 800.00 ft x 80.00 ft x 22.00 ft (normal load)
 244.80 m / 243.84 m x 24.38 m  x 6.71 m

Armament:
      2 - 12.00" / 305 mm guns (1x2 guns), 864.00lbs / 391.90kg shells, 1915 Model
   Breech loading guns in a turret (on a barbette)
   on centreline forward
      12 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1915 Model
   Quick firing guns in deck mounts with hoists
   on side, all amidships
 Weight of broadside 3,024 lbs / 1,372 kg
 Shells per gun, main battery: 80

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 4.00" / 102 mm 640.00 ft / 195.07 m 17.00 ft / 5.18 m
 Ends: Unarmoured
   Main Belt covers 123 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.50" / 38 mm 640.00 ft / 195.07 m 19.00 ft / 5.79 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       -         -

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

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 206,306 shp / 153,904 Kw = 37.00 kts
 Range 5,400nm at 15.00 kts
 Bunker at max displacement = 1,846 tons

Complement:
 840 - 1,093

Cost:
 £2.510 million / $10.041 million

Distribution of weights at normal displacement:
 Armament: 378 tons, 1.9 %
 Armour: 3,678 tons, 18.4 %
    - Belts: 1,756 tons, 8.8 %
    - Torpedo bulkhead: 675 tons, 3.4 %
    - Armament: 397 tons, 2.0 %
    - Armour Deck: 787 tons, 3.9 %
    - Conning Tower: 63 tons, 0.3 %
 Machinery: 5,452 tons, 27.3 %
 Hull, fittings & equipment: 8,922 tons, 44.6 %
 Fuel, ammunition & stores: 1,570 tons, 7.8 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   28,481 lbs / 12,919 Kg = 33.0 x 12.0 " / 305 mm shells or 3.3 torpedoes
 Stability (Unstable if below 1.00): 1.26
 Metacentric height 5.5 ft / 1.7 m
 Roll period: 14.4 seconds
 Steadiness - As gun platform (Average = 50 %): 63 %
   - Recoil effect (Restricted arc if above 1.00): 0.33
 Seaboat quality  (Average = 1.00): 1.26

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.497
 Length to Beam Ratio: 10.00 : 1
 'Natural speed' for length: 28.28 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:  33.00 ft / 10.06 m
    - Forecastle (20 %): 30.00 ft / 9.14 m
    - Mid (67 %):  30.00 ft / 9.14 m (22.00 ft / 6.71 m aft of break)
    - Quarterdeck (15 %): 22.00 ft / 6.71 m
    - Stern:  22.00 ft / 6.71 m
    - Average freeboard: 27.60 ft / 8.41 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 137.0 %
  - Above water (accommodation/working, high = better): 268.0 %
 Waterplane Area: 42,532 Square feet or 3,951 Square metres
 Displacement factor (Displacement / loading): 114 %
 Structure weight / hull surface area: 133 lbs/sq ft or 651 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.96
  - Longitudinal: 1.40
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent
 Good seaboat, rides out heavy weather easily

Thursday, June 23, 2005

The gun intended for the "Super Fast Battlecruiser" was the 17in/45

As I have previously mentioned, I had a design for a 17in/45 gun that fired an AP shot of 2,814 lbs. The muzzle velocity was 2,850 ft/sec. The muzzle energy was 158,397 foot-tons. The length was 63.75 ft. This was to form the main armament of the so-called "Super Fast Battlecruiser", which was to supercede the GB/CB/1905, GB/CB/1907, and GB/CB/1910 ships.

The BBX revisited

This is my friend Cliff's concept for a slow, heavily protected and armed super battleship. He called it the "BBX". In this case, we underestimated what could be done on a given displacement. This is the Springsharp report:
GB/BB/1915 BBX, Great Britain Enter ship type laid down 1915 (Engine 1927)

Displacement:
 63,033 t light; 66,113 t standard; 70,000 t normal; 73,109 t full load

Dimensions: Length overall / water x beam x draught
 801.73 ft / 800.00 ft x 135.00 ft x 36.50 ft (normal load)
 244.37 m / 243.84 m x 41.15 m  x 11.13 m

Armament:
      9 - 20.00" / 508 mm guns (3x3 guns), 4,000.00lbs / 1,814.37kg shells, 1915 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, majority forward, 1 raised mount - superfiring
      24 - 5.00" / 127 mm guns (12x2 guns), 62.50lbs / 28.35kg shells, 1915 Model
   Quick firing guns in turrets (on barbettes)
   on side, all amidships, 4 raised mounts - superfiring
 Weight of broadside 37,500 lbs / 17,010 kg
 Shells per gun, main battery: 80

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 18.0" / 457 mm 560.00 ft / 170.69 m 17.00 ft / 5.18 m
 Ends: Unarmoured
   Main Belt covers 108 % of normal length

   - Torpedo Bulkhead:
  3.00" / 76 mm 560.00 ft / 170.69 m 32.00 ft / 9.75 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: 4.00" / 102 mm 4.00" / 102 mm  4.00" / 102 mm

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

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 66,006 shp / 49,240 Kw = 22.00 kts
 Range 7,500nm at 16.00 kts
 Bunker at max displacement = 6,996 tons

Complement:
 2,151 - 2,797

Cost:
 £9.361 million / $37.442 million

Distribution of weights at normal displacement:
 Armament: 4,688 tons, 6.7 %
 Armour: 28,632 tons, 40.9 %
    - Belts: 7,443 tons, 10.6 %
    - Torpedo bulkhead: 1,989 tons, 2.8 %
    - Armament: 6,614 tons, 9.4 %
    - Armour Deck: 11,927 tons, 17.0 %
    - Conning Tower: 659 tons, 0.9 %
 Machinery: 2,084 tons, 3.0 %
 Hull, fittings & equipment: 27,631 tons, 39.5 %
 Fuel, ammunition & stores: 6,967 tons, 10.0 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   109,024 lbs / 49,452 Kg = 27.3 x 20.0 " / 508 mm shells or 21.3 torpedoes
 Stability (Unstable if below 1.00): 1.11
 Metacentric height 9.6 ft / 2.9 m
 Roll period: 18.3 seconds
 Steadiness - As gun platform (Average = 50 %): 72 %
   - Recoil effect (Restricted arc if above 1.00): 0.63
 Seaboat quality  (Average = 1.00): 1.45

Hull form characteristics:
 Hull has a flush deck
 Block coefficient: 0.622
 Length to Beam Ratio: 5.93 : 1
 'Natural speed' for length: 28.28 kts
 Power going to wave formation at top speed: 40 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 3.00 degrees
 Stern overhang: -1.00 ft / -0.30 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  33.00 ft / 10.06 m
    - Forecastle (20 %): 24.00 ft / 7.32 m
    - Mid (50 %):  23.00 ft / 7.01 m
    - Quarterdeck (15 %): 23.00 ft / 7.01 m
    - Stern:  24.00 ft / 7.32 m
    - Average freeboard: 24.15 ft / 7.36 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 70.2 %
  - Above water (accommodation/working, high = better): 165.8 %
 Waterplane Area: 80,588 Square feet or 7,487 Square metres
 Displacement factor (Displacement / loading): 100 %
 Structure weight / hull surface area: 262 lbs/sq ft or 1,281 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.96
  - Longitudinal: 1.52
  - 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

Wednesday, June 22, 2005

The "Ultra Fast" version of the GB/CB/1910 design

My 1972 or 1973 version of the GB/CB/1910 battlecruiser design was intended to be very fast. The speed was too fast for what was feasible, sadly. I had thought that 300,000 SHP might be possible, and that seems to be true. This design was intended to have a thicker belt, although 9in is just a guess. The armament was 4-13.5in/45 BLR and 8-4in QF guns. What is remarkable is that the normal displacement is what was intended. This is the Springsharp report:
GB/CB/1910 Ultra Fast, Great Britain Battlecruiser laid down 1910 (Engine 1933)

Displacement:
 29,611 t light; 30,557 t standard; 33,000 t normal; 34,954 t full load

Dimensions: Length overall / water x beam x draught
 775.00 ft / 775.00 ft x 90.00 ft x 31.00 ft (normal load)
 236.22 m / 236.22 m x 27.43 m  x 9.45 m

Armament:
      4 - 13.50" / 343 mm guns (2x2 guns), 1,350.00lbs / 612.35kg shells, 1910 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread
      8 - 4.00" / 102 mm guns (4x2 guns), 32.00lbs / 14.51kg shells, 1910 Model
   Quick firing guns in deck mounts with hoists
   on side, all amidships, 2 raised mounts - superfiring
 Weight of broadside 5,656 lbs / 2,566 kg
 Shells per gun, main battery: 90

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 9.00" / 229 mm 620.00 ft / 188.98 m 17.00 ft / 5.18 m
 Ends: Unarmoured
   Main Belt covers 123 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.50" / 38 mm 620.00 ft / 188.98 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  8.00" / 203 mm
 2nd: 2.00" / 51 mm       -         -

   - Armour deck: 2.50" / 64 mm, Conning tower: 8.00" / 203 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 295,918 shp / 220,755 Kw = 37.00 kts
 Range 6,200nm at 18.00 kts
 Bunker at max displacement = 4,397 tons

Complement:
 1,223 - 1,591

Cost:
 £2.787 million / $11.148 million

Distribution of weights at normal displacement:
 Armament: 647 tons, 2.0 %
 Armour: 8,173 tons, 24.8 %
    - Belts: 3,869 tons, 11.7 %
    - Torpedo bulkhead: 929 tons, 2.8 %
    - Armament: 979 tons, 3.0 %
    - Armour Deck: 2,218 tons, 6.7 %
    - Conning Tower: 177 tons, 0.5 %
 Machinery: 8,622 tons, 26.1 %
 Hull, fittings & equipment: 12,169 tons, 36.9 %
 Fuel, ammunition & stores: 3,389 tons, 10.3 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   41,243 lbs / 18,707 Kg = 33.5 x 13.5 " / 343 mm shells or 4.5 torpedoes
 Stability (Unstable if below 1.00): 1.24
 Metacentric height 6.3 ft / 1.9 m
 Roll period: 15.0 seconds
 Steadiness - As gun platform (Average = 50 %): 53 %
   - Recoil effect (Restricted arc if above 1.00): 0.37
 Seaboat quality  (Average = 1.00): 1.06

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.534
 Length to Beam Ratio: 8.61 : 1
 'Natural speed' for length: 27.84 kts
 Power going to wave formation at top speed: 61 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): -1.00 degrees
 Stern overhang: -1.00 ft / -0.30 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  35.00 ft / 10.67 m
    - Forecastle (20 %): 32.00 ft / 9.75 m
    - Mid (67 %):  32.00 ft / 9.75 m (24.00 ft / 7.32 m aft of break)
    - Quarterdeck (15 %): 24.00 ft / 7.32 m
    - Stern:  24.00 ft / 7.32 m
    - Average freeboard: 29.60 ft / 9.02 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 128.3 %
  - Above water (accommodation/working, high = better): 222.5 %
 Waterplane Area: 47,962 Square feet or 4,456 Square metres
 Displacement factor (Displacement / loading): 108 %
 Structure weight / hull surface area: 159 lbs/sq ft or 774 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.95
  - Longitudinal: 1.70
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

A rework of my "48,000 ton battlecruiser" design

Well, this is only nominally a 48,000 ton ship, as my Springsharp design came out heavier, due to structural strength needs. The design is for a ship of 855ft x 105ft x 33.3ft with a speed of 30 knots. The armament is 9-16in/45 BLR and 20-5in QF guns. The armor basis is 14inches. This is the Springsharp report:
GB/CB/1921 48,000 tons, Great Britain Battlecruiser laid down 1921 (Engine 1937)

Displacement:
 43,640 t light; 45,621 t standard; 49,250 t normal; 52,153 t full load

Dimensions: Length overall / water x beam x draught
 856.57 ft / 855.00 ft x 105.00 ft x 33.30 ft (normal load)
 261.08 m / 260.60 m x 32.00 m  x 10.15 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
      20 - 5.00" / 127 mm guns (10x2 guns), 62.00lbs / 28.12kg shells, 1921 Model
   Quick firing guns in turrets (on barbettes)
   on side, all amidships, 4 raised mounts - superfiring
 Weight of broadside 19,672 lbs / 8,923 kg
 Shells per gun, main battery: 90

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 14.0" / 356 mm 555.00 ft / 169.16 m 17.00 ft / 5.18 m
 Ends: Unarmoured
   Main Belt covers 100 % of normal length

   - Torpedo Bulkhead:
  2.00" / 51 mm 555.00 ft / 169.16 m 29.00 ft / 8.84 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: 4.00" / 102 mm 4.00" / 102 mm  4.00" / 102 mm

   - Armour deck: 5.00" / 127 mm, Conning tower: 12.00" / 305 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 161,252 shp / 120,294 Kw = 30.00 kts
 Range 7,500nm at 18.00 kts
 Bunker at max displacement = 6,532 tons

Complement:
 1,652 - 2,148

Cost:
 £10.741 million / $42.964 million

Distribution of weights at normal displacement:
 Armament: 2,460 tons, 5.0 %
 Armour: 17,357 tons, 35.2 %
    - Belts: 5,627 tons, 11.4 %
    - Torpedo bulkhead: 1,191 tons, 2.4 %
    - Armament: 4,250 tons, 8.6 %
    - Armour Deck: 5,942 tons, 12.1 %
    - Conning Tower: 347 tons, 0.7 %
 Machinery: 4,469 tons, 9.1 %
 Hull, fittings & equipment: 19,353 tons, 39.3 %
 Fuel, ammunition & stores: 5,610 tons, 11.4 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   71,719 lbs / 32,531 Kg = 35.0 x 16.0 " / 406 mm shells or 10.6 torpedoes
 Stability (Unstable if below 1.00): 1.08
 Metacentric height 6.2 ft / 1.9 m
 Roll period: 17.7 seconds
 Steadiness - As gun platform (Average = 50 %): 62 %
   - Recoil effect (Restricted arc if above 1.00): 0.78
 Seaboat quality  (Average = 1.00): 1.24

Hull form characteristics:
 Hull has a flush deck
 Block coefficient: 0.577
 Length to Beam Ratio: 8.14 : 1
 'Natural speed' for length: 29.24 kts
 Power going to wave formation at top speed: 49 %
 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:  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 tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 83.1 %
  - Above water (accommodation/working, high = better): 177.8 %
 Waterplane Area: 64,237 Square feet or 5,968 Square metres
 Displacement factor (Displacement / loading): 107 %
 Structure weight / hull surface area: 210 lbs/sq ft or 1,026 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.98
  - Longitudinal: 1.20
  - 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

"Pushing the envelope": Ger/CL/1915 Very Fast

I have this pencil drawing from 1971 and some minimal specifications. I was "dreaming" when I thought that 50 or 60 knots might be achievable. It definitely is not achievable in Springsharp, and not on 7,000 tons with 175,000 SHP with 45SHP/ton of machinery weight. The ship is 625ft long and is a fast cruiser. I guessed that the armament would be 4-6in guns, grouped forward, as was my preference at the time. This is the resulting Sprinsharp report:
Ger/CL/1915 Very Fast, Enter country Enter ship type laid down 1915 (Engine 1950)

Displacement:
 8,637 t light; 8,865 t standard; 9,600 t normal; 10,188 t full load

Dimensions: Length overall / water x beam x draught
 628.52 ft / 625.00 ft x 62.00 ft x 23.00 ft (normal load)
 191.57 m / 190.50 m x 18.90 m  x 7.01 m

Armament:
      4 - 6.00" / 152 mm guns (2x2 guns), 108.00lbs / 48.99kg shells, 1915 Model
   Quick firing guns in deck mounts with hoists
   on centreline, all forward, 1 raised mount - superfiring
 Weight of broadside 432 lbs / 196 kg
 Shells per gun, main battery: 150

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 168,902 shp / 126,001 Kw = 39.00 kts
 Range 4,500nm at 18.00 kts
 Bunker at max displacement = 1,322 tons

Complement:
 484 - 630

Cost:
 £1.329 million / $5.314 million

Distribution of weights at normal displacement:
 Armament: 54 tons, 0.6 %
 Machinery: 4,041 tons, 42.1 %
 Hull, fittings & equipment: 4,543 tons, 47.3 %
 Fuel, ammunition & stores: 963 tons, 10.0 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   7,588 lbs / 3,442 Kg = 70.3 x 6.0 " / 152 mm shells or 1.0 torpedoes
 Stability (Unstable if below 1.00): 1.29
 Metacentric height 3.9 ft / 1.2 m
 Roll period: 13.3 seconds
 Steadiness - As gun platform (Average = 50 %): 72 %
   - Recoil effect (Restricted arc if above 1.00): 0.14
 Seaboat quality  (Average = 1.00): 1.43

Hull form characteristics:
 Hull has a flush deck
 Block coefficient: 0.377
 Length to Beam Ratio: 10.08 : 1
 'Natural speed' for length: 25.00 kts
 Power going to wave formation at top speed: 60 %
 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:  29.00 ft / 8.84 m
    - Forecastle (20 %): 25.00 ft / 7.62 m
    - Mid (50 %):  25.00 ft / 7.62 m
    - Quarterdeck (15 %): 25.00 ft / 7.62 m
    - Stern:  25.00 ft / 7.62 m
    - Average freeboard: 25.32 ft / 7.72 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 140.7 %
  - Above water (accommodation/working, high = better): 232.2 %
 Waterplane Area: 23,602 Square feet or 2,193 Square metres
 Displacement factor (Displacement / loading): 113 %
 Structure weight / hull surface area: 100 lbs/sq ft or 490 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.89
  - Longitudinal: 2.96
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent
 Ship has slow, easy roll, a good, steady gun platform
 Good seaboat, rides out heavy weather easily

New version of the Ger/BB/1905 Flush Decked (UPDATED further)

This is the new version of my Ger/BB/1905 Flush Decked battleship design. I had pencil drawings dating from the early 1970's of this concept for both German battleship and battlecruiser for 1905. This is the photo of the battleship, which is also used as a logo for this blog. There had been some ambiguities in the forecastle deck and the foremast that I resolved for my present satisfaction. That may mean that I eventually make further changes after staring at the photo for a few months.

The scout cruiser design Ger/CS/1915

I don't believe that I have written about this previously. I have a pencil drawing for a scout cruiser design to be part of the emergency war program for 1915. They were to be called S-8 to S-19, so I would have built 12. The armament was 4-6in QF guns and 4-23.6in TT. The look is very German with two funnels with slanting caps and a raised forecastle that is relatively short. This is the Springsharp report:
Ger/CS/1915, Germany Scout Cruiser laid down 1915 (Engine 1933)

Displacement:
 2,121 t light; 2,206 t standard; 2,606 t normal; 2,926 t full load

Dimensions: Length overall / water x beam x draught
 355.87 ft / 355.00 ft x 37.00 ft x 16.00 ft (normal load)
 108.47 m / 108.20 m x 11.28 m  x 4.88 m

Armament:
      4 - 6.00" / 152 mm guns in single mounts, 100.00lbs / 45.36kg shells, 1915 Model
   Breech loading guns in deck mounts with hoists
   on centreline ends, evenly spread, 1 raised mount
 Weight of broadside 400 lbs / 181 kg
 Shells per gun, main battery: 150
 4 - 23.6" / 599.44 mm above water torpedoes

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 2 shafts, 59,122 shp / 44,105 Kw = 34.00 kts
 Range 4,500nm at 18.00 kts
 Bunker at max displacement = 720 tons

Complement:
 182 - 237

Cost:
 £0.464 million / $1.856 million

Distribution of weights at normal displacement:
 Armament: 54 tons, 2.1 %
 Machinery: 1,424 tons, 54.7 %
 Hull, fittings & equipment: 642 tons, 24.7 %
 Fuel, ammunition & stores: 485 tons, 18.6 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   551 lbs / 250 Kg = 5.1 x 6.0 " / 152 mm shells or 0.3 torpedoes
 Stability (Unstable if below 1.00): 1.53
 Metacentric height 2.3 ft / 0.7 m
 Roll period: 10.2 seconds
 Steadiness - As gun platform (Average = 50 %): 53 %
   - Recoil effect (Restricted arc if above 1.00): 0.41
 Seaboat quality  (Average = 1.00): 1.06

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.434
 Length to Beam Ratio: 9.59 : 1
 'Natural speed' for length: 18.84 kts
 Power going to wave formation at top speed: 70 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 2.00 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 %): 23.00 ft / 7.01 m
    - Mid (26 %):  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: 17.24 ft / 5.25 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 192.0 %
  - Above water (accommodation/working, high = better): 100.2 %
 Waterplane Area: 8,273 Square feet or 769 Square metres
 Displacement factor (Displacement / loading): 67 %
 Structure weight / hull surface area: 35 lbs/sq ft or 172 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.44
  - Longitudinal: 2.45
  - Overall: 0.52
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is adequate

Tuesday, June 21, 2005

By giving a little on protection, 37 knots is possible

This is a slight revision to the extreme version of the GB/CB/1907 so that 37 knots can be achieved. A modest reduction in protection makes it possible, along with slightly higher output machinery.
GB/CB/1907 Extreme version, Enter country Enter ship type laid down 1907 (Engine 1927)

Displacement:
 24,322 t light; 25,076 t standard; 27,500 t normal; 29,439 t full load

Dimensions: Length overall / water x beam x draught
 770.00 ft / 770.00 ft x 80.00 ft x 28.00 ft (normal load)
 234.70 m / 234.70 m x 24.38 m  x 8.53 m

Armament:
      4 - 12.00" / 305 mm guns (2x2 guns), 864.00lbs / 391.90kg shells, 1907 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread
      9 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1907 Model
   Quick firing guns in deck mounts with hoists
   on side, all amidships
 Weight of broadside 4,428 lbs / 2,009 kg
 Shells per gun, main battery: 80

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 5.00" / 127 mm 660.00 ft / 201.17 m 8.00 ft / 2.44 m
 Ends: Unarmoured
 Upper: 5.00" / 127 mm 400.00 ft / 121.92 m 8.00 ft / 2.44 m
   Main Belt covers 132 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.50" / 38 mm 660.00 ft / 201.17 m 26.00 ft / 7.92 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 7.00" / 178 mm 4.00" / 102 mm  7.00" / 178 mm
 2nd: 2.00" / 51 mm       -         -

   - Armour deck: 2.00" / 51 mm, Conning tower: 5.00" / 127 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 263,437 shp / 196,524 Kw = 37.00 kts
 Range 6,500nm at 18.00 kts
 Bunker at max displacement = 4,363 tons

Complement:
 1,067 - 1,388

Cost:
 £2.480 million / $9.922 million

Distribution of weights at normal displacement:
 Armament: 554 tons, 2.0 %
 Armour: 5,130 tons, 18.7 %
    - Belts: 1,755 tons, 6.4 %
    - Torpedo bulkhead: 952 tons, 3.5 %
    - Armament: 722 tons, 2.6 %
    - Armour Deck: 1,603 tons, 5.8 %
    - Conning Tower: 98 tons, 0.4 %
 Machinery: 8,316 tons, 30.2 %
 Hull, fittings & equipment: 10,323 tons, 37.5 %
 Fuel, ammunition & stores: 3,178 tons, 11.6 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   27,785 lbs / 12,603 Kg = 32.2 x 12.0 " / 305 mm shells or 3.0 torpedoes
 Stability (Unstable if below 1.00): 1.24
 Metacentric height 5.3 ft / 1.6 m
 Roll period: 14.6 seconds
 Steadiness - As gun platform (Average = 50 %): 59 %
   - Recoil effect (Restricted arc if above 1.00): 0.46
 Seaboat quality  (Average = 1.00): 1.17

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.558
 Length to Beam Ratio: 9.63 : 1
 'Natural speed' for length: 27.75 kts
 Power going to wave formation at top speed: 60 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): -1.00 degrees
 Stern overhang: -1.00 ft / -0.30 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  34.00 ft / 10.36 m
    - Forecastle (20 %): 31.00 ft / 9.45 m
    - Mid (73 %):  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: 29.08 ft / 8.86 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 150.8 %
  - Above water (accommodation/working, high = better): 228.3 %
 Waterplane Area: 43,315 Square feet or 4,024 Square metres
 Displacement factor (Displacement / loading): 105 %
 Structure weight / hull surface area: 142 lbs/sq ft or 692 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.94
  - Longitudinal: 1.68
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

The extreme version of the GB/CB/1907 class

The GB/CB/1907 class were larger and carried 12in/50 guns instead of the 12in/45 guns carried by the GB/CB/1905 class. They also could carry increased armour, do to their greater displacement (27,500 tons). This is the Springsharp report:
GB/CB/1907 Extreme version, Enter country Enter ship type laid down 1907 (Engine 1925)

Displacement:
 24,274 t light; 25,028 t standard; 27,500 t normal; 29,478 t full load

Dimensions: Length overall / water x beam x draught
 770.00 ft / 770.00 ft x 80.00 ft x 28.00 ft (normal load)
 234.70 m / 234.70 m x 24.38 m  x 8.53 m

Armament:
      4 - 12.00" / 305 mm guns (2x2 guns), 864.00lbs / 391.90kg shells, 1907 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread
      9 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1907 Model
   Quick firing guns in deck mounts with hoists
   on side, all amidships
 Weight of broadside 4,428 lbs / 2,009 kg
 Shells per gun, main battery: 80

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 6.00" / 152 mm 690.00 ft / 210.31 m 9.00 ft / 2.74 m
 Ends: Unarmoured
 Upper: 6.00" / 152 mm 400.00 ft / 121.92 m 8.00 ft / 2.44 m
   Main Belt covers 138 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.50" / 38 mm 690.00 ft / 210.31 m 26.00 ft / 7.92 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 8.00" / 203 mm 4.00" / 102 mm  7.00" / 178 mm
 2nd: 2.00" / 51 mm       -         -

   - Armour deck: 2.00" / 51 mm, Conning tower: 8.00" / 203 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 235,359 shp / 175,578 Kw = 36.00 kts
 Range 6,500nm at 18.00 kts
 Bunker at max displacement = 4,450 tons

Complement:
 1,067 - 1,388

Cost:
 £2.384 million / $9.537 million

Distribution of weights at normal displacement:
 Armament: 554 tons, 2.0 %
 Armour: 5,807 tons, 21.1 %
    - Belts: 2,317 tons, 8.4 %
    - Torpedo bulkhead: 996 tons, 3.6 %
    - Armament: 734 tons, 2.7 %
    - Armour Deck: 1,603 tons, 5.8 %
    - Conning Tower: 157 tons, 0.6 %
 Machinery: 7,642 tons, 27.8 %
 Hull, fittings & equipment: 10,272 tons, 37.4 %
 Fuel, ammunition & stores: 3,226 tons, 11.7 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   31,798 lbs / 14,423 Kg = 36.8 x 12.0 " / 305 mm shells or 3.5 torpedoes
 Stability (Unstable if below 1.00): 1.21
 Metacentric height 5.1 ft / 1.6 m
 Roll period: 14.9 seconds
 Steadiness - As gun platform (Average = 50 %): 63 %
   - Recoil effect (Restricted arc if above 1.00): 0.48
 Seaboat quality  (Average = 1.00): 1.26

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.558
 Length to Beam Ratio: 9.63 : 1
 'Natural speed' for length: 27.75 kts
 Power going to wave formation at top speed: 58 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): -1.00 degrees
 Stern overhang: -1.00 ft / -0.30 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  34.00 ft / 10.36 m
    - Forecastle (20 %): 31.00 ft / 9.45 m
    - Mid (73 %):  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: 29.08 ft / 8.86 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 140.4 %
  - Above water (accommodation/working, high = better): 228.3 %
 Waterplane Area: 43,315 Square feet or 4,024 Square metres
 Displacement factor (Displacement / loading): 108 %
 Structure weight / hull surface area: 141 lbs/sq ft or 688 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.94
  - Longitudinal: 1.69
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent
 Good seaboat, rides out heavy weather easily

An "extreme version" of the GB/CB/1905 battlecruiser

My intent in about 1972 was to have a very high speed version of the GB/CB/1905 design. I just ran such a version through Springsharp. It was made possible by having a lightweight machinery plant. If you require a lower output machinery plant, then you are lucky to reach 33 knots, the originally planned speed. This Springsharp report is very good, if you accept the machinery weight. This is a really dominant, fast cruiser that sacrifices protection and gunpower for extreme speed and good seakeeping characteristics:
GB/CB/1905 Extreme version, Enter country Enter ship type laid down 1905 (Engine 1921)

Displacement:
 23,260 t light; 23,987 t standard; 26,500 t normal; 28,510 t full load

Dimensions: Length overall / water x beam x draught
 770.00 ft / 770.00 ft x 80.00 ft x 28.00 ft (normal load)
 234.70 m / 234.70 m x 24.38 m  x 8.53 m

Armament:
      4 - 12.00" / 305 mm guns (2x2 guns), 850.00lbs / 385.55kg shells, 1905 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread
      9 - 6.00" / 152 mm guns in single mounts, 100.00lbs / 45.36kg shells, 1905 Model
   Quick firing guns in deck mounts with hoists
   on side, all amidships
 Weight of broadside 4,300 lbs / 1,950 kg
 Shells per gun, main battery: 80

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 4.00" / 102 mm 660.00 ft / 201.17 m 9.00 ft / 2.74 m
 Ends: Unarmoured
 Upper: 4.00" / 102 mm 400.00 ft / 121.92 m 8.00 ft / 2.44 m
   Main Belt covers 132 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.50" / 38 mm 660.00 ft / 201.17 m 26.00 ft / 7.92 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       -         -

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

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 227,821 shp / 169,954 Kw = 36.00 kts
 Range 6,500nm at 18.00 kts
 Bunker at max displacement = 4,523 tons

Complement:
 1,038 - 1,350

Cost:
 £2.377 million / $9.509 million

Distribution of weights at normal displacement:
 Armament: 554 tons, 2.1 %
 Armour: 4,792 tons, 18.1 %
    - Belts: 1,508 tons, 5.7 %
    - Torpedo bulkhead: 952 tons, 3.6 %
    - Armament: 644 tons, 2.4 %
    - Armour Deck: 1,572 tons, 5.9 %
    - Conning Tower: 115 tons, 0.4 %
 Machinery: 7,845 tons, 29.6 %
 Hull, fittings & equipment: 10,069 tons, 38.0 %
 Fuel, ammunition & stores: 3,240 tons, 12.2 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   27,712 lbs / 12,570 Kg = 32.1 x 12.0 " / 305 mm shells or 3.1 torpedoes
 Stability (Unstable if below 1.00): 1.24
 Metacentric height 5.3 ft / 1.6 m
 Roll period: 14.6 seconds
 Steadiness - As gun platform (Average = 50 %): 65 %
   - Recoil effect (Restricted arc if above 1.00): 0.47
 Seaboat quality  (Average = 1.00): 1.30

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.538
 Length to Beam Ratio: 9.63 : 1
 'Natural speed' for length: 27.75 kts
 Power going to wave formation at top speed: 58 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): -1.00 degrees
 Stern overhang: -1.00 ft / -0.30 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  34.00 ft / 10.36 m
    - Forecastle (20 %): 31.00 ft / 9.45 m
    - Mid (73 %):  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: 29.08 ft / 8.86 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 148.8 %
  - Above water (accommodation/working, high = better): 230.2 %
 Waterplane Area: 42,500 Square feet or 3,948 Square metres
 Displacement factor (Displacement / loading): 106 %
 Structure weight / hull surface area: 140 lbs/sq ft or 684 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.94
  - Longitudinal: 1.71
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent
 Good seaboat, rides out heavy weather easily

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