Amazon Ad

Tuesday, July 31, 2007

The Ger/DD/1905 design in Springsharp 3.0b2 Beta

I have really struggled to get the Ger/DD/1905 design to work in Springsharp 3.0b2. To achieve adequate seakeeping, the displacement had to be reduced considerably. Because of that, hull strength became an issue. This is a 32 knot ship with 2-4in QF guns and 2-18in TT. The ship has three funnels and a raised forecastle. This is a photograph of a Ger/DD/1905 destroyer:

This is the Springsharp report:
Ger/DD/1905, Germany Destroyer laid down 1905 (Engine 1950)

Displacement:
 702 t light; 726 t standard; 832 t normal; 916 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (272.31 ft / 270.00 ft) x 28.00 ft x (10.00 / 10.64 ft)
 (83.00 m / 82.30 m) x 8.53 m  x (3.05 / 3.24 m)

Armament:
      2 - 4.00" / 102 mm 50.0 cal guns - 32.00lbs / 14.51kg shells, 150 per gun
   Quick firing guns in deck and hoist mounts, 1905 Model
   2 x Single mounts on centreline ends, evenly spread
      Weight of broadside 64 lbs / 29 kg
      2 - 18.0" / 457 mm, 20.00 ft / 6.10 m torpedoes - 0.865 t each, 1.729 t total
 In 2 sets of deck mounted carriage/fixed tubes

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

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 2 shafts, 24,938 shp / 18,604 Kw = 32.00 kts
 Range 3,600nm at 16.00 kts
 Bunker at max displacement = 190 tons

Complement:
 76 - 100

Cost:
 £0.090 million / $0.361 million

Distribution of weights at normal displacement:
 Armament: 23 tons, 2.7 %
    - Guns: 21 tons, 2.5 %
    - Torpedoes: 2 tons, 0.2 %
 Armour: 14 tons, 1.7 %
    - Armament: 14 tons, 1.7 %
 Machinery: 417 tons, 50.2 %
 Hull, fittings & equipment: 248 tons, 29.9 %
 Fuel, ammunition & stores: 129 tons, 15.5 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   254 lbs / 115 Kg = 7.9 x 4.0 " / 102 mm shells or 0.2 torpedoes
 Stability (Unstable if below 1.00): 1.28
 Metacentric height 1.2 ft / 0.4 m
 Roll period: 10.9 seconds
 Steadiness - As gun platform (Average = 50 %): 54 %
   - Recoil effect (Restricted arc if above 1.00): 0.20
 Seaboat quality  (Average = 1.00): 1.02

Hull form characteristics:
 Hull has rise forward of midbreak,
   a normal bow and a round stern
 Block coefficient (normal/deep): 0.385 / 0.399
 Length to Beam Ratio: 9.64 : 1
 'Natural speed' for length: 16.43 kts
 Power going to wave formation at top speed: 70 %
 Trim (Max stability = 0, Max steadiness = 100): 53
 Bow angle (Positive = bow angles forward): 6.00 degrees
 Stern overhang: 0.00 ft / 0.00 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 15.00 %,  22.00 ft / 6.71 m,  19.50 ft / 5.94 m
    - Forward deck: 15.00 %,  19.50 ft / 5.94 m,  19.00 ft / 5.79 m
    - Aft deck: 55.00 %,  11.00 ft / 3.35 m,  11.00 ft / 3.35 m
    - Quarter deck: 15.00 %,  11.00 ft / 3.35 m,  11.00 ft / 3.35 m
    - Average freeboard:  13.66 ft / 4.16 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 170.1 %
  - Above water (accommodation/working, high = better): 145.5 %
 Waterplane Area: 4,607 Square feet or 428 Square metres
 Displacement factor (Displacement / loading): 65 %
 Structure weight / hull surface area: 25 lbs/sq ft or 124 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.43
  - Longitudinal: 3.01
  - Overall: 0.52
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

Monday, July 30, 2007

An attempt at William Hovgaard's "Battleship-Cruiser" in 1903

I wanted to see what could be done with using 1903 technology to implement William Hovgaard's Battleship-Cruiser concept. He wanted a fast battleship that might sacrifice a few guns to still have heavy armour and a high speed. I was able to have 8-12in/45, 12-6in QF guns, an 10in belt, and 24 knots speed. To do that with reciprocating engines and coal-fired boilers demands a very large ship. My Springsharp design is 25,911 tons standard. This is the Springsharp report:
GB/BB/1903, Great Britain Battleship-Cruiser laid down 1903

Displacement:
 24,902 t light; 25,911 t standard; 28,487 t normal; 30,547 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (593.00 ft / 585.00 ft) x 90.00 ft x (29.00 / 30.78 ft)
 (180.75 m / 178.31 m) x 27.43 m  x (8.84 / 9.38 m)

Armament:
      8 - 12.00" / 305 mm 45.0 cal guns - 850.00lbs / 385.55kg shells, 90 per gun
   Breech loading guns in turret on barbette mounts, 1903 Model
   2 x Twin mounts on centreline ends, evenly spread
   2 x Twin mounts on sides, forward deck aft
      12 - 6.00" / 152 mm 45.0 cal guns - 100.00lbs / 45.36kg shells, 150 per gun
   Quick firing guns in casemate mounts, 1903 Model
   6 x Single mounts on sides, forward deck aft
   6 x Single mounts on sides, aft deck forward
      Weight of broadside 8,000 lbs / 3,629 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 10.0" / 254 mm 380.00 ft / 115.82 m 8.00 ft / 2.44 m
 Ends: 4.00" / 102 mm 120.00 ft / 36.58 m 12.00 ft / 3.66 m
   85.00 ft / 25.91 m Unarmoured ends
 Upper: 7.00" / 178 mm 380.00 ft / 115.82 m 8.00 ft / 2.44 m
   Main Belt covers 100 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.00" / 25 mm 380.00 ft / 115.82 m 26.00 ft / 7.92 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 10.0" / 254 mm 7.00" / 178 mm  10.0" / 254 mm
 2nd: 5.00" / 127 mm 4.00" / 102 mm  5.00" / 127 mm

   - Protected deck - single deck: 3.00" / 76 mm For and Aft decks
 Forecastle: 3.00" / 76 mm  Quarter deck: 3.00" / 76 mm

   - Conning towers: Forward 10.00" / 254 mm,  Aft 0.00" / 0 mm

Machinery:
 Coal fired boilers, complex reciprocating steam engines, 
 Direct drive, 4 shafts, 57,734 ihp / 43,070 Kw = 24.00 kts
 Range 4,800nm at 14.00 kts
 Bunker at max displacement = 4,635 tons (100% coal)

Complement:
 1,096 - 1,425

Cost:
 £2.790 million / $11.162 million

Distribution of weights at normal displacement:
 Armament: 1,462 tons, 5.1 %
 Armour: 7,044 tons, 24.7 %
    - Belts: 2,480 tons, 8.7 %
    - Torpedo bulkhead: 366 tons, 1.3 %
    - Armament: 1,736 tons, 6.1 %
    - Armour Deck: 2,261 tons, 7.9 %
    - Conning Tower: 201 tons, 0.7 %
 Machinery: 8,617 tons, 30.2 %
 Hull, fittings & equipment: 7,779 tons, 27.3 %
 Fuel, ammunition & stores: 3,585 tons, 12.6 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   19,976 lbs / 9,061 Kg = 23.1 x 12.0 " / 305 mm shells or 2.5 torpedoes
 Stability (Unstable if below 1.00): 1.22
 Metacentric height 6.2 ft / 1.9 m
 Roll period: 15.2 seconds
 Steadiness - As gun platform (Average = 50 %): 96 %
   - Recoil effect (Restricted arc if above 1.00): 0.52
 Seaboat quality  (Average = 1.00): 1.35

Hull form characteristics:
 Hull has rise forward of midbreak,
   a ram bow and a cruiser stern
 Block coefficient (normal/deep): 0.653 / 0.660
 Length to Beam Ratio: 6.50 : 1
 'Natural speed' for length: 24.19 kts
 Power going to wave formation at top speed: 52 %
 Trim (Max stability = 0, Max steadiness = 100): 71
 Bow angle (Positive = bow angles forward): -3.00 degrees
 Stern overhang: -3.00 ft / -0.91 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 30.00 %,  24.00 ft / 7.32 m,  24.00 ft / 7.32 m
    - Forward deck: 33.00 %,  24.00 ft / 7.32 m,  24.00 ft / 7.32 m
    - Aft deck: 22.00 %,  16.00 ft / 4.88 m,  16.00 ft / 4.88 m
    - Quarter deck: 15.00 %,  16.00 ft / 4.88 m,  16.00 ft / 4.88 m
    - Average freeboard:  21.04 ft / 6.41 m
 Ship tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 155.0 %
  - Above water (accommodation/working, high = better): 146.2 %
 Waterplane Area: 40,444 Square feet or 3,757 Square metres
 Displacement factor (Displacement / loading): 92 %
 Structure weight / hull surface area: 147 lbs/sq ft or 715 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.96
  - Longitudinal: 1.45
  - 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

Sunday, July 29, 2007

A rare photograph of the USS Brooklyn in 1905

I have this rare photograph of the belted cruiser USS Brooklyn taken in 1905. The Brooklyn was completed in 1896 and originally carried 8-8in and 10-5in guns, as well as 12 smaller guns. These are probably nominal figures. The displacement was 9,215 tons and the dimensions were 400ft-6in x 64ft-8in x 24ft. The Brooklyn had four vertical triple expansion engines and seven Scotch boilers. The IHP was 18,425. While very light on trials, the Brooklyn reached 21.91 knots.

Saturday, July 28, 2007

The USS Topeka, unarmoured cruiser

Over at "My Victorian Navy", I have posted a rare photograph of the unarmoured cruiser USS Topeka. The photograph was taken in 1898, when the Topeka was painted gray. I thought that I would try the Topeka in Springsharp. One issue that the exact mean draft is in dispute. The source for the photograph gives the mean draft as only 15ft-6in. I have seen other sources that give the draft as over 17ft. The primary problem with my Springsharp design is that the roll period is too short. I had to experiment to get the roll period over a short 11 seconds. The Topeka originally carried 8-4in guns, but later had the guns reduced to 6-4in. The speed was 16 knots. A sister ship lasted a long time in the Peruvian navy as the Lima. This is the Springsharp report:
USS Topeka, United States Cruiser laid down 1881

Displacement:
 1,558 t light; 1,626 t standard; 2,414 t normal; 3,044 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (271.00 ft / 259.00 ft) x 35.00 ft x (17.75 / 21.32 ft)
 (82.60 m / 78.94 m) x 10.67 m  x (5.41 / 6.50 m)

Armament:
      2 - 4.00" / 102 mm 40.0 cal guns - 28.00lbs / 12.70kg shells, 150 per gun
   Breech loading guns in deck and hoist mounts, 1881 Model
   2 x Single mounts on centreline ends, evenly spread
      6 - 4.00" / 102 mm 40.0 cal guns - 28.00lbs / 12.70kg shells, 150 per gun
   Breech loading guns in casemate mounts, 1881 Model
   6 x Single mounts on sides, forward deck aft
  6 hull mounts in casemates- Limited use in all but light seas
      2 - 2.24" / 57.0 mm 40.0 cal guns - 6.00lbs / 2.72kg shells, 150 per gun
   Breech loading guns in deck mounts, 1881 Model
   2 x Single mounts on sides, aft deck forward
      Weight of broadside 236 lbs / 107 kg

Machinery:
 Coal fired boilers, simple reciprocating steam engines, 
 Direct drive, 2 shafts, 3,519 ihp / 2,625 Kw = 16.00 kts
 Range 5,600nm at 12.00 kts
 Bunker at max displacement = 1,418 tons (100% coal)

Complement:
 171 - 223

Cost:
 £0.168 million / $0.671 million

Distribution of weights at normal displacement:
 Armament: 40 tons, 1.6 %
 Machinery: 717 tons, 29.7 %
 Hull, fittings & equipment: 801 tons, 33.2 %
 Fuel, ammunition & stores: 855 tons, 35.4 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   2,382 lbs / 1,080 Kg = 86.0 x 4.0 " / 102 mm shells or 0.6 torpedoes
 Stability (Unstable if below 1.00): 1.27
 Metacentric height 1.6 ft / 0.5 m
 Roll period: 11.7 seconds
 Steadiness - As gun platform (Average = 50 %): 100 %
   - Recoil effect (Restricted arc if above 1.00): 0.25
 Seaboat quality  (Average = 1.00): 2.00

Hull form characteristics:
 Hull has a flush deck,
   a normal bow and a cruiser stern
 Block coefficient (normal/deep): 0.525 / 0.551
 Length to Beam Ratio: 7.40 : 1
 'Natural speed' for length: 16.09 kts
 Power going to wave formation at top speed: 46 %
 Trim (Max stability = 0, Max steadiness = 100): 75
 Bow angle (Positive = bow angles forward): -2.00 degrees
 Stern overhang: 12.00 ft / 3.66 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 25.00 %,  18.00 ft / 5.49 m,  16.00 ft / 4.88 m
    - Forward deck: 30.00 %,  16.00 ft / 4.88 m,  15.00 ft / 4.57 m
    - Aft deck: 30.00 %,  15.00 ft / 4.57 m,  15.00 ft / 4.57 m
    - Quarter deck: 15.00 %,  15.00 ft / 4.57 m,  15.00 ft / 4.57 m
    - Average freeboard:  15.60 ft / 4.75 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 102.1 %
  - Above water (accommodation/working, high = better): 105.0 %
 Waterplane Area: 6,180 Square feet or 574 Square metres
 Displacement factor (Displacement / loading): 155 %
 Structure weight / hull surface area: 63 lbs/sq ft or 305 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.84
  - Longitudinal: 5.23
  - Overall: 1.01
 Hull space for machinery, storage, compartmentation is adequate
 Room for accommodation and workspaces is adequate
 Ship has slow, easy roll, a good, steady gun platform
 Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Friday, July 27, 2007

I thought that I would try to do a better version of what I had originally specified at the "My Victorian Navy" blog

I thought that I would like to see if I could design a 23 knot version of the 21 knot British armoured cruiser that can be seen at the "My Victorian Navy" blog. This is a ship with a 6in armour basis, a 2in deck, 4-9.2in/45 and 14-6in QF guns. The design was inspired by the British-built armoured cruisers built for the Japanese navy. This is the Springsharp report:
GB/CA/1902, Great Britain Armoured Cruiser laid down 1902

Displacement:
 13,919 t light; 14,470 t standard; 16,653 t normal; 18,399 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (502.00 ft / 495.00 ft) x 75.00 ft x (25.00 / 27.19 ft)
 (153.01 m / 150.88 m) x 22.86 m  x (7.62 / 8.29 m)

Armament:
      4 - 9.20" / 234 mm 45.0 cal guns - 380.00lbs / 172.37kg shells, 120 per gun
   Breech loading guns in turret on barbette mounts, 1902 Model
   2 x Twin mounts on centreline ends, evenly spread
      14 - 6.00" / 152 mm 45.0 cal guns - 100.00lbs / 45.36kg shells, 150 per gun
   Quick firing guns in casemate mounts, 1902 Model
   14 x Single mounts on sides, evenly spread
  8 hull mounts in casemates- Limited use in heavy seas
      Weight of broadside 2,920 lbs / 1,324 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 6.00" / 152 mm 320.00 ft / 97.54 m 16.00 ft / 4.88 m
 Ends: 4.00" / 102 mm 175.00 ft / 53.34 m 12.00 ft / 3.66 m
   Main Belt covers 99 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.00" / 25 mm 320.00 ft / 97.54 m 25.00 ft / 7.62 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

   - Protected deck - single deck: 2.00" / 51 mm For and Aft decks
 Forecastle: 2.00" / 51 mm  Quarter deck: 2.00" / 51 mm

   - Conning towers: Forward 6.00" / 152 mm,  Aft 0.00" / 0 mm

Machinery:
 Coal fired boilers, complex reciprocating steam engines, 
 Direct drive, 2 shafts, 36,801 ihp / 27,453 Kw = 23.00 kts
 Range 5,600nm at 14.00 kts
 Bunker at max displacement = 3,929 tons (100% coal)

Complement:
 732 - 952

Cost:
 £1.487 million / $5.947 million

Distribution of weights at normal displacement:
 Armament: 610 tons, 3.7 %
 Armour: 3,612 tons, 21.7 %
    - Belts: 1,653 tons, 9.9 %
    - Torpedo bulkhead: 296 tons, 1.8 %
    - Armament: 541 tons, 3.2 %
    - Armour Deck: 1,038 tons, 6.2 %
    - Conning Tower: 84 tons, 0.5 %
 Machinery: 5,576 tons, 33.5 %
 Hull, fittings & equipment: 4,121 tons, 24.7 %
 Fuel, ammunition & stores: 2,734 tons, 16.4 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   14,089 lbs / 6,391 Kg = 36.2 x 9.2 " / 234 mm shells or 1.9 torpedoes
 Stability (Unstable if below 1.00): 1.66
 Metacentric height 7.5 ft / 2.3 m
 Roll period: 11.5 seconds
 Steadiness - As gun platform (Average = 50 %): 77 %
   - Recoil effect (Restricted arc if above 1.00): 0.18
 Seaboat quality  (Average = 1.00): 1.53

Hull form characteristics:
 Hull has a flush deck,
   a ram bow and a cruiser stern
 Block coefficient (normal/deep): 0.628 / 0.638
 Length to Beam Ratio: 6.60 : 1
 'Natural speed' for length: 22.25 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 (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 25.00 %,  24.00 ft / 7.32 m,  21.00 ft / 6.40 m
    - Forward deck: 30.00 %,  21.00 ft / 6.40 m,  19.00 ft / 5.79 m
    - Aft deck: 20.00 %,  19.00 ft / 5.79 m,  19.00 ft / 5.79 m
    - Quarter deck: 25.00 %,  19.00 ft / 5.79 m,  20.00 ft / 6.10 m
    - Average freeboard:  20.23 ft / 6.16 m
 Ship tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 165.1 %
  - Above water (accommodation/working, high = better): 142.1 %
 Waterplane Area: 27,869 Square feet or 2,589 Square metres
 Displacement factor (Displacement / loading): 99 %
 Structure weight / hull surface area: 109 lbs/sq ft or 530 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.94
  - Longitudinal: 1.68
  - Overall: 0.99
 Caution: Hull subject to strain in open-sea
 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
 Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Thursday, July 26, 2007

One of my favorite ship drawings and designs: the Ger/CS/1905

The Ger/CS/1905 is one of my favorite ship designs. I also really like the drawing that I did back in 2005. Sadly, in Springsharp, the design cannot be realized completely. The issue seems to revolve around Springsharp requiring too much power for a given speed and not being able to specify light-enough machinery. The best I can get from Springsharp is about 49 SHP/ton of machinery. When you realize that the British leader Swift was designed in 1905 and had 60 SHP/ton machinery, you can see the nature of the problem. This is the Springsharp report:
Ger/CS/1905, Germany Scout Cruiser laid down 1905 (Engine 1950)

Displacement:
 1,888 t light; 1,946 t standard; 2,141 t normal; 2,297 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (372.10 ft / 370.00 ft) x 38.00 ft x (13.00 / 13.63 ft)
 (113.42 m / 112.78 m) x 11.58 m  x (3.96 / 4.15 m)

Armament:
      5 - 4.00" / 102 mm 50.0 cal guns - 32.00lbs / 14.51kg shells, 150 per gun
   Quick firing guns in deck and hoist mounts, 1905 Model
   3 x Single mounts on centreline ends, majority aft
   2 x Single mounts on sides, forward deck aft
      Weight of broadside 160 lbs / 73 kg
      2 - 18.0" / 457 mm, 20.00 ft / 6.10 m torpedoes - 0.865 t each, 1.729 t total
 In 2 sets of deck mounted carriage/fixed tubes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 2.00" / 51 mm 180.00 ft / 54.86 m 8.00 ft / 2.44 m
 Ends: Unarmoured
 Upper: 2.00" / 51 mm 100.00 ft / 30.48 m 8.00 ft / 2.44 m
   Main Belt covers 75 % of normal length
   Main belt does not fully cover magazines and engineering spaces

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

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 2 shafts, 49,817 shp / 37,163 Kw = 34.00 kts
 Range 4,500nm at 15.00 kts
 Bunker at max displacement = 352 tons

Complement:
 156 - 204

Cost:
 £0.227 million / $0.906 million

Distribution of weights at normal displacement:
 Armament: 54 tons, 2.5 %
    - Guns: 52 tons, 2.4 %
    - Torpedoes: 2 tons, 0.1 %
 Armour: 270 tons, 12.6 %
    - Belts: 204 tons, 9.5 %
    - Armament: 67 tons, 3.1 %
 Machinery: 1,017 tons, 47.5 %
 Hull, fittings & equipment: 547 tons, 25.6 %
 Fuel, ammunition & stores: 253 tons, 11.8 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   678 lbs / 307 Kg = 21.2 x 4.0 " / 102 mm shells or 0.4 torpedoes
 Stability (Unstable if below 1.00): 1.26
 Metacentric height 1.8 ft / 0.5 m
 Roll period: 11.9 seconds
 Steadiness - As gun platform (Average = 50 %): 54 %
   - Recoil effect (Restricted arc if above 1.00): 0.18
 Seaboat quality  (Average = 1.00): 1.01

Hull form characteristics:
 Hull has rise forward of midbreak,
   a normal bow and a round stern
 Block coefficient (normal/deep): 0.410 / 0.420
 Length to Beam Ratio: 9.74 : 1
 'Natural speed' for length: 19.24 kts
 Power going to wave formation at top speed: 67 %
 Trim (Max stability = 0, Max steadiness = 100): 53
 Bow angle (Positive = bow angles forward): 5.00 degrees
 Stern overhang: 0.00 ft / 0.00 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 16.00 %,  24.00 ft / 7.32 m,  22.00 ft / 6.71 m
    - Forward deck: 12.00 %,  22.00 ft / 6.71 m,  22.00 ft / 6.71 m
    - Aft deck: 57.00 %,  14.00 ft / 4.27 m,  14.00 ft / 4.27 m
    - Quarter deck: 15.00 %,  14.00 ft / 4.27 m,  14.00 ft / 4.27 m
    - Average freeboard:  16.37 ft / 4.99 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 161.2 %
  - Above water (accommodation/working, high = better): 162.5 %
 Waterplane Area: 8,707 Square feet or 809 Square metres
 Displacement factor (Displacement / loading): 76 %
 Structure weight / hull surface area: 34 lbs/sq ft or 165 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.46
  - Longitudinal: 1.72
  - Overall: 0.52
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

Wednesday, July 25, 2007

So, what does it take to get a small fast ship?

By taking some extreme measures in Springsharp 3.0b2 Beta, I was able to get a 35 knot destroyer leader, not in 1909, but in 1917. The extreme measures include the lightest possible machinery, a narrow beam, a high freeboard, and a deep draft. This is the result: the Ger/DL/1917. The ship has 4-5in guns and 4-23.6in TT. This is the Springsharp report:
Ger/DL/1917, Germany Destroyer Leader laid down 1917 (Engine 1950)

Displacement:
 1,704 t light; 1,772 t standard; 1,971 t normal; 2,131 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (353.23 ft / 350.00 ft) x 32.00 ft x (14.00 / 14.79 ft)
 (107.67 m / 106.68 m) x 9.75 m  x (4.27 / 4.51 m)

Armament:
      4 - 5.00" / 127 mm 50.0 cal guns - 65.00lbs / 29.48kg shells, 150 per gun
   Quick firing guns in deck and hoist mounts, 1917 Model
   3 x Single mounts on centreline ends, majority aft
   1 x Single mount on centreline, aft deck forward
  1 raised mount aft
      Weight of broadside 260 lbs / 118 kg
      4 - 23.6" / 599 mm, 22.00 ft / 6.71 m torpedoes - 1.751 t each, 7.005 t total
 In 2 sets of deck mounted centre rotating tubes

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

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 2 shafts, 55,449 shp / 41,365 Kw = 35.00 kts
 Range 4,800nm at 15.00 kts
 Bunker at max displacement = 359 tons

Complement:
 147 - 192

Cost:
 £0.422 million / $1.689 million

Distribution of weights at normal displacement:
 Armament: 86 tons, 4.4 %
    - Guns: 79 tons, 4.0 %
    - Torpedoes: 7 tons, 0.4 %
 Armour: 60 tons, 3.0 %
    - Armament: 60 tons, 3.0 %
 Machinery: 1,033 tons, 52.4 %
 Hull, fittings & equipment: 525 tons, 26.6 %
 Fuel, ammunition & stores: 268 tons, 13.6 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   436 lbs / 198 Kg = 7.0 x 5.0 " / 127 mm shells or 0.3 torpedoes
 Stability (Unstable if below 1.00): 1.14
 Metacentric height 1.2 ft / 0.4 m
 Roll period: 12.5 seconds
 Steadiness - As gun platform (Average = 50 %): 51 %
   - Recoil effect (Restricted arc if above 1.00): 0.63
 Seaboat quality  (Average = 1.00): 1.01

Hull form characteristics:
 Hull has rise forward of midbreak,
   a normal bow and a round stern
 Block coefficient (normal/deep): 0.440 / 0.450
 Length to Beam Ratio: 10.94 : 1
 'Natural speed' for length: 18.71 kts
 Power going to wave formation at top speed: 70 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 8.00 degrees
 Stern overhang: 0.00 ft / 0.00 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 15.00 %,  23.00 ft / 7.01 m,  22.00 ft / 6.71 m
    - Forward deck: 17.00 %,  22.00 ft / 6.71 m,  22.00 ft / 6.71 m
    - Aft deck: 53.00 %,  14.00 ft / 4.27 m,  14.00 ft / 4.27 m
    - Quarter deck: 15.00 %,  14.00 ft / 4.27 m,  14.00 ft / 4.27 m
    - Average freeboard:  16.62 ft / 5.07 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 182.0 %
  - Above water (accommodation/working, high = better): 116.7 %
 Waterplane Area: 7,087 Square feet or 658 Square metres
 Displacement factor (Displacement / loading): 66 %
 Structure weight / hull surface area: 33 lbs/sq ft or 162 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.43
  - Longitudinal: 2.64
  - Overall: 0.52
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is adequate

Tuesday, July 24, 2007

The original concept for the Ger/CS/1905 scouts

My original concept for the Ger/CS/1905 scouts was to be a ship of 2,200 tons, with dimensions 365ft x 37ft x 12ft, with a speed of 37 knots. I had optimistically hoped that about 45,000 SHP would be sufficient to make that speed. The armament was 6-4in QF guns in the lozenge arrangement and there were 2-18in TT. There was no armour, except guns shields and protection to the hoists. The cost was to be £198,000. To make the design work in Springsharp, the machinery had to be very light and the displacement was reduced considerably below the 2,200 tons. Somewhat more than 45,000 SHP was required just to reach 34 knots, much less 37 knots. This is the Springsharp report:
Ger/CS/1905 Original Concept, Germany Scout Cruiser laid down 1905 (Engine 1950)

Displacement:
 1,624 t light; 1,683 t standard; 1,898 t normal; 2,071 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (365.00 ft / 365.00 ft) x 37.00 ft x (12.00 / 12.72 ft)
 (111.25 m / 111.25 m) x 11.28 m  x (3.66 / 3.88 m)

Armament:
      6 - 4.00" / 102 mm 50.0 cal guns - 32.00lbs / 14.51kg shells, 180 per gun
   Quick firing guns in deck and hoist mounts, 1905 Model
   2 x Single mounts on centreline ends, evenly spread
   4 x Single mounts on sides, evenly spread
      Weight of broadside 192 lbs / 87 kg
      2 - 18.0" / 457 mm, 20.00 ft / 6.10 m torpedoes - 0.865 t each, 1.729 t total
 In 2 sets of deck mounted centre rotating tubes

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

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 46,400 shp / 34,614 Kw = 34.00 kts
 Range 5,400nm at 15.00 kts
 Bunker at max displacement = 389 tons

Complement:
 143 - 186

Cost:
 £0.209 million / $0.838 million

Distribution of weights at normal displacement:
 Armament: 64 tons, 3.4 %
    - Guns: 62 tons, 3.3 %
    - Torpedoes: 2 tons, 0.1 %
 Armour: 80 tons, 4.2 %
    - Armament: 80 tons, 4.2 %
 Machinery: 934 tons, 49.2 %
 Hull, fittings & equipment: 546 tons, 28.7 %
 Fuel, ammunition & stores: 275 tons, 14.5 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   597 lbs / 271 Kg = 18.6 x 4.0 " / 102 mm shells or 0.3 torpedoes
 Stability (Unstable if below 1.00): 1.27
 Metacentric height 1.7 ft / 0.5 m
 Roll period: 11.8 seconds
 Steadiness - As gun platform (Average = 50 %): 53 %
   - Recoil effect (Restricted arc if above 1.00): 0.24
 Seaboat quality  (Average = 1.00): 1.06

Hull form characteristics:
 Hull has rise forward of midbreak,
   a normal bow and a cruiser stern
 Block coefficient (normal/deep): 0.410 / 0.422
 Length to Beam Ratio: 9.86 : 1
 'Natural speed' for length: 19.10 kts
 Power going to wave formation at top speed: 67 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 0.00 degrees
 Stern overhang: -2.00 ft / -0.61 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 18.00 %,  23.00 ft / 7.01 m,  22.00 ft / 6.71 m
    - Forward deck: 15.00 %,  22.00 ft / 6.71 m,  22.00 ft / 6.71 m
    - Aft deck: 52.00 %,  14.00 ft / 4.27 m,  14.00 ft / 4.27 m
    - Quarter deck: 15.00 %,  14.00 ft / 4.27 m,  14.00 ft / 4.27 m
    - Average freeboard:  16.71 ft / 5.09 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 169.5 %
  - Above water (accommodation/working, high = better): 144.7 %
 Waterplane Area: 8,363 Square feet or 777 Square metres
 Displacement factor (Displacement / loading): 76 %
 Structure weight / hull surface area: 34 lbs/sq ft or 168 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.46
  - Longitudinal: 1.98
  - Overall: 0.54
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

Monday, July 23, 2007

Another shot at a Ger/CS/1909 scout

This is the original specification for the Ger/CS/1909 scout:
Scout   2100 tons  4-5in QF guns, 2-21in TT
   350ft x 37ft x 12ft  Cp=0.56  Cm=0.85
  45 SHP/ton = 1000 tons machinery       45,000 SHP
                900 tons hull
                 44 tons armament
                168 tons miscellaneous

I took that a tried to see what could be done with Springsharp 3.0b2 Beta. I wanted the 45,000 SHP and about 1000 tons of machinery. I ended up having to go with a lower displacement, to achieve adequate seakeeping. This is a photograph of one of the ships at sea:

This is the Springsharp report:
Ger/CS/1909, Germany Scout laid down 1909 (Engine 1937)

Displacement:
 1,598 t light; 1,660 t standard; 1,874 t normal; 2,045 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (350.00 ft / 350.00 ft) x 37.00 ft x (12.00 / 12.74 ft)
 (106.68 m / 106.68 m) x 11.28 m  x (3.66 / 3.88 m)

Armament:
      4 - 5.00" / 127 mm 50.0 cal guns - 66.16lbs / 30.01kg shells, 150 per gun
   Quick firing guns in deck and hoist mounts, 1909 Model
   3 x Single mounts on centreline ends, majority aft
   1 x Single mount on centreline, forward deck aft
  1 raised mount aft
      Weight of broadside 265 lbs / 120 kg
      2 - 21.0" / 533 mm, 20.00 ft / 6.10 m torpedoes - 1.259 t each, 2.518 t total
 In 2 sets of deck mounted centre rotating tubes

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

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 2 shafts, 44,965 shp / 33,544 Kw = 33.50 kts
 Range 4,800nm at 15.00 kts
 Bunker at max displacement = 385 tons

Complement:
 142 - 185

Cost:
 £0.220 million / $0.879 million

Distribution of weights at normal displacement:
 Armament: 82 tons, 4.4 %
    - Guns: 79 tons, 4.2 %
    - Torpedoes: 3 tons, 0.1 %
 Armour: 36 tons, 1.9 %
    - Armament: 36 tons, 1.9 %
 Machinery: 970 tons, 51.8 %
 Hull, fittings & equipment: 509 tons, 27.2 %
 Fuel, ammunition & stores: 276 tons, 14.7 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   503 lbs / 228 Kg = 8.0 x 5.0 " / 127 mm shells or 0.3 torpedoes
 Stability (Unstable if below 1.00): 1.30
 Metacentric height 1.8 ft / 0.5 m
 Roll period: 11.6 seconds
 Steadiness - As gun platform (Average = 50 %): 54 %
   - Recoil effect (Restricted arc if above 1.00): 0.38
 Seaboat quality  (Average = 1.00): 1.02

Hull form characteristics:
 Hull has rise forward of midbreak,
   a normal bow and a cruiser stern
 Block coefficient (normal/deep): 0.422 / 0.434
 Length to Beam Ratio: 9.46 : 1
 'Natural speed' for length: 18.71 kts
 Power going to wave formation at top speed: 68 %
 Trim (Max stability = 0, Max steadiness = 100): 53
 Bow angle (Positive = bow angles forward): 0.00 degrees
 Stern overhang: -3.00 ft / -0.91 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 15.00 %,  22.00 ft / 6.71 m,  22.00 ft / 6.71 m
    - Forward deck: 18.00 %,  22.00 ft / 6.71 m,  22.00 ft / 6.71 m
    - Aft deck: 52.00 %,  14.00 ft / 4.27 m,  14.00 ft / 4.27 m
    - Quarter deck: 15.00 %,  14.00 ft / 4.27 m,  14.00 ft / 4.27 m
    - Average freeboard:  16.64 ft / 5.07 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 180.8 %
  - Above water (accommodation/working, high = better): 142.1 %
 Waterplane Area: 8,085 Square feet or 751 Square metres
 Displacement factor (Displacement / loading): 67 %
 Structure weight / hull surface area: 34 lbs/sq ft or 167 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.44
  - Longitudinal: 2.10
  - Overall: 0.52
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

Sunday, July 22, 2007

The GB/CL/1914 design study

I have a sketch design from the early 1970's for a variant of the British C-class light cruisers. the side armour is very limited and of 2in thickness. The deck armour is 1in, but is a complete deck. the guns are 4-6in/50 QF guns and there are 8-21in TT. The look is very much like a C-class ship, except the speed is 32 knots. The idea was to get a higher speed in exchange for lighter protection. This is the Springsharp report:
GB/CL/1914, Great Britain Light Cruiser laid down 1914 (Engine 1943)

Displacement:
 3,820 t light; 3,950 t standard; 4,344 t normal; 4,658 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (456.47 ft / 450.00 ft) x 41.00 ft x (16.00 / 16.88 ft)
 (139.13 m / 137.16 m) x 12.50 m  x (4.88 / 5.15 m)

Armament:
      4 - 6.00" / 152 mm 50.0 cal guns - 100.00lbs / 45.36kg shells, 150 per gun
   Quick firing guns in deck and hoist mounts, 1914 Model
   3 x Single mounts on centreline ends, majority aft
   1 x Single mount on centreline, aft deck forward
  1 raised mount aft
      Weight of broadside 400 lbs / 181 kg
      8 - 21.0" / 533 mm, 20.00 ft / 6.10 m torpedoes - 1.279 t each, 10.231 t total
 In 4 sets of deck mounted side rotating tubes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 2.00" / 51 mm 305.00 ft / 92.96 m 8.00 ft / 2.44 m
 Ends: Unarmoured
 Upper: 2.00" / 51 mm 120.00 ft / 36.58 m 8.00 ft / 2.44 m
   Main Belt covers 104 % of normal length
   Main belt does not fully cover magazines and engineering spaces

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

   - Armoured deck - multiple decks: 1.00" / 25 mm For and Aft decks
 Forecastle: 1.00" / 25 mm  Quarter deck: 1.00" / 25 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 2 shafts, 56,545 shp / 42,182 Kw = 32.00 kts
 Range 5,600nm at 15.00 kts
 Bunker at max displacement = 708 tons

Complement:
 266 - 347

Cost:
 £0.491 million / $1.966 million

Distribution of weights at normal displacement:
 Armament: 145 tons, 3.3 %
    - Guns: 135 tons, 3.1 %
    - Torpedoes: 10 tons, 0.2 %
 Armour: 622 tons, 14.3 %
    - Belts: 290 tons, 6.7 %
    - Armament: 99 tons, 2.3 %
    - Armour Deck: 232 tons, 5.4 %
 Machinery: 1,460 tons, 33.6 %
 Hull, fittings & equipment: 1,592 tons, 36.7 %
 Fuel, ammunition & stores: 524 tons, 12.1 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   3,656 lbs / 1,658 Kg = 33.8 x 6.0 " / 152 mm shells or 0.8 torpedoes
 Stability (Unstable if below 1.00): 1.08
 Metacentric height 1.5 ft / 0.5 m
 Roll period: 13.9 seconds
 Steadiness - As gun platform (Average = 50 %): 53 %
   - Recoil effect (Restricted arc if above 1.00): 0.37
 Seaboat quality  (Average = 1.00): 1.02

Hull form characteristics:
 Hull has rise forward of midbreak,
   an extended bulbous bow and a cruiser stern
 Block coefficient (normal/deep): 0.515 / 0.523
 Length to Beam Ratio: 10.98 : 1
 'Natural speed' for length: 21.21 kts
 Power going to wave formation at top speed: 62 %
 Trim (Max stability = 0, Max steadiness = 100): 52
 Bow angle (Positive = bow angles forward): 11.00 degrees
 Stern overhang: 2.00 ft / 0.61 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 17.00 %,  23.00 ft / 7.01 m,  22.00 ft / 6.71 m
    - Forward deck: 16.00 %,  22.00 ft / 6.71 m,  22.00 ft / 6.71 m
    - Aft deck: 52.00 %,  14.00 ft / 4.27 m,  14.00 ft / 4.27 m
    - Quarter deck: 15.00 %,  14.00 ft / 4.27 m,  14.00 ft / 4.27 m
    - Average freeboard:  16.71 ft / 5.09 m
 Ship tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 119.2 %
  - Above water (accommodation/working, high = better): 137.6 %
 Waterplane Area: 12,463 Square feet or 1,158 Square metres
 Displacement factor (Displacement / loading): 109 %
 Structure weight / hull surface area: 71 lbs/sq ft or 347 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.93
  - Longitudinal: 1.94
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

Saturday, July 21, 2007

The GB/CA/1909 armoured cruiser

The Blue Book has several references to an armoured cruiser with 6-12in/50 and 8-6in/50 guns. The armour basis is 6in and the deck, amidships, is 3in. The design works reasonably well in Springsharp, and the default machinery weight produces power for 27 knots. This is a photograph of one of the ships:

This is the Springsharp report:
GB/CA/1907, Great Britain Armoured Cruiser laid down 1909

Displacement:
 15,134 t light; 15,827 t standard; 17,600 t normal; 19,019 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (555.00 ft / 550.00 ft) x 80.00 ft x (25.00 / 26.60 ft)
 (169.16 m / 167.64 m) x 24.38 m  x (7.62 / 8.11 m)

Armament:
      6 - 12.00" / 305 mm 50.0 cal guns - 914.66lbs / 414.88kg shells, 90 per gun
   Breech loading guns in turret on barbette mounts, 1909 Model
   2 x Triple mounts on centreline ends, evenly spread
      8 - 6.00" / 152 mm 50.0 cal guns - 100.00lbs / 45.36kg shells, 150 per gun
   Quick firing guns in casemate mounts, 1909 Model
   8 x Single mounts on sides, forward deck aft
  8 hull mounts in casemates- Limited use in heavy seas
      Weight of broadside 6,288 lbs / 2,852 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 6.00" / 152 mm 350.00 ft / 106.68 m 16.00 ft / 4.88 m
 Ends: Unarmoured
   Main Belt covers 98 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.00" / 25 mm 350.00 ft / 106.68 m 25.00 ft / 7.62 m

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

   - Protected deck - single deck: 3.00" / 76 mm For and Aft decks
 Forecastle: 2.00" / 51 mm  Quarter deck: 2.00" / 51 mm

   - Conning towers: Forward 6.00" / 152 mm,  Aft 0.00" / 0 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 67,326 shp / 50,225 Kw = 27.00 kts
 Range 5,600nm at 15.00 kts
 Bunker at max displacement = 3,192 tons

Complement:
 763 - 993

Cost:
 £1.575 million / $6.301 million

Distribution of weights at normal displacement:
 Armament: 1,257 tons, 7.1 %
 Armour: 4,240 tons, 24.1 %
    - Belts: 1,454 tons, 8.3 %
    - Torpedo bulkhead: 324 tons, 1.8 %
    - Armament: 872 tons, 5.0 %
    - Armour Deck: 1,503 tons, 8.5 %
    - Conning Tower: 87 tons, 0.5 %
 Machinery: 3,060 tons, 17.4 %
 Hull, fittings & equipment: 6,576 tons, 37.4 %
 Fuel, ammunition & stores: 2,466 tons, 14.0 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   26,909 lbs / 12,206 Kg = 31.1 x 12.0 " / 305 mm shells or 3.5 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 %): 72 %
   - Recoil effect (Restricted arc if above 1.00): 0.71
 Seaboat quality  (Average = 1.00): 1.43

Hull form characteristics:
 Hull has low quarterdeck ,
   a ram bow and a cruiser stern
 Block coefficient (normal/deep): 0.560 / 0.569
 Length to Beam Ratio: 6.88 : 1
 'Natural speed' for length: 23.45 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 (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 25.00 %,  29.00 ft / 8.84 m,  28.00 ft / 8.53 m
    - Forward deck: 30.00 %,  28.00 ft / 8.53 m,  28.00 ft / 8.53 m
    - Aft deck: 12.00 %,  28.00 ft / 8.53 m,  28.00 ft / 8.53 m
    - Quarter deck: 33.00 %,  20.00 ft / 6.10 m,  20.00 ft / 6.10 m
    - Average freeboard:  25.46 ft / 7.76 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 117.5 %
  - Above water (accommodation/working, high = better): 216.7 %
 Waterplane Area: 30,997 Square feet or 2,880 Square metres
 Displacement factor (Displacement / loading): 108 %
 Structure weight / hull surface area: 149 lbs/sq ft or 725 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.90
  - Longitudinal: 2.45
  - 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

Friday, July 20, 2007

The big and fast GB/CA/1921 "Fast"

This version of the GB/CA/1921 is trying to be compatible with my very fast light cruiser for the same date. This design is more complete and has an AA and light AA armament as well as a main armament. The ship is designed for a 37 knot speed. To achieve that with 9-9.2in/55 guns and acceptable hull strength and sea keeping takes a large ship in Springsharp 3.0b2 Beta. The displacement is 18,099 tons standard. To be that small requires substantial length, to improve sea keeping and to reduce the required power. This is the Springsharp report:
GB/CA/1921 Fast, Great Britain Heavy Cruiser laid down 1921 (Engine 1941)

Displacement:
 17,431 t light; 18,099 t standard; 19,351 t normal; 20,352 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (726.65 ft / 715.00 ft) x 72.00 ft x (23.00 / 23.92 ft)
 (221.48 m / 217.93 m) x 21.95 m  x (7.01 / 7.29 m)

Armament:
      9 - 9.20" / 234 mm 55.0 cal guns - 420.00lbs / 190.51kg shells, 120 per gun
   Breech loading guns in turret on barbette mounts, 1921 Model
   3 x Triple mounts on centreline ends, majority forward
  1 raised mount - superfiring
      6 - 4.70" / 119 mm 45.0 cal guns - 52.35lbs / 23.75kg shells, 150 per gun
   Anti-air guns in deck and hoist mounts, 1921 Model
   6 x Single mounts on sides, aft deck forward
  6 raised mounts
      16 - 1.57" / 40.0 mm 45.0 cal guns - 2.00lbs / 0.91kg shells, 150 per gun
   Breech loading guns in deck mounts, 1921 Model
   4 x 2 row quad mounts on sides, forward deck aft
  4 raised mounts
      Weight of broadside 4,126 lbs / 1,872 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 4.00" / 102 mm 490.00 ft / 149.35 m 12.00 ft / 3.66 m
 Ends: Unarmoured
   Main Belt covers 105 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  0.80" / 20 mm 490.00 ft / 149.35 m 22.00 ft / 6.71 m

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

   - Armoured deck - multiple decks: 2.00" / 51 mm For and Aft decks
 Forecastle: 2.00" / 51 mm  Quarter deck: 2.00" / 51 mm

   - Conning towers: Forward 4.00" / 102 mm,  Aft 0.00" / 0 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 190,303 shp / 141,966 Kw = 37.00 kts
 Range 6,500nm at 15.00 kts
 Bunker at max displacement = 2,253 tons

Complement:
 819 - 1,066

Cost:
 £4.528 million / $18.112 million

Distribution of weights at normal displacement:
 Armament: 1,122 tons, 5.8 %
 Armour: 3,326 tons, 17.2 %
    - Belts: 965 tons, 5.0 %
    - Torpedo bulkhead: 319 tons, 1.6 %
    - Armament: 557 tons, 2.9 %
    - Armour Deck: 1,423 tons, 7.4 %
    - Conning Tower: 62 tons, 0.3 %
 Machinery: 5,029 tons, 26.0 %
 Hull, fittings & equipment: 7,954 tons, 41.1 %
 Fuel, ammunition & stores: 1,919 tons, 9.9 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   23,565 lbs / 10,689 Kg = 60.5 x 9.2 " / 234 mm shells or 2.5 torpedoes
 Stability (Unstable if below 1.00): 1.08
 Metacentric height 3.6 ft / 1.1 m
 Roll period: 16.0 seconds
 Steadiness - As gun platform (Average = 50 %): 55 %
   - Recoil effect (Restricted arc if above 1.00): 0.79
 Seaboat quality  (Average = 1.00): 1.10

Hull form characteristics:
 Hull has low quarterdeck ,
   an extended bulbous bow and large transom stern
 Block coefficient (normal/deep): 0.572 / 0.579
 Length to Beam Ratio: 9.93 : 1
 'Natural speed' for length: 30.30 kts
 Power going to wave formation at top speed: 61 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 15.00 degrees
 Stern overhang: 2.00 ft / 0.61 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 28.00 %,  36.00 ft / 10.97 m,  29.00 ft / 8.84 m
    - Forward deck: 30.00 %,  29.00 ft / 8.84 m,  29.00 ft / 8.84 m
    - Aft deck: 15.00 %,  29.00 ft / 8.84 m,  29.00 ft / 8.84 m
    - Quarter deck: 27.00 %,  21.00 ft / 6.40 m,  21.00 ft / 6.40 m
    - Average freeboard:  27.62 ft / 8.42 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 146.9 %
  - Above water (accommodation/working, high = better): 257.7 %
 Waterplane Area: 38,202 Square feet or 3,549 Square metres
 Displacement factor (Displacement / loading): 109 %
 Structure weight / hull surface area: 135 lbs/sq ft or 661 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.94
  - Longitudinal: 1.83
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

Thursday, July 19, 2007

A fast British 1921 light cruiser

The GB/CL/1921 "Fast" light cruiser was an attempt to see what might be achieved with Springsharp 3.0b2 Beta. This ship carried 9-6in/55 QF guns and 12-21in TT at a speed of 37 knots. It has a range of 5400nm at 15 knots. I added some protection, including a thin torpedo bulkhead. It would be heavily damaged, but might survive on torpedo. This is the Springsharp report:
GB/CL/1921 Fast, Great Britain Light Cruiser laid down 1921 (Engine 1941)

Displacement:
 10,647 t light; 10,984 t standard; 11,752 t normal; 12,366 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (622.04 ft / 614.00 ft) x 58.00 ft x (22.00 / 22.85 ft)
 (189.60 m / 187.15 m) x 17.68 m  x (6.71 / 6.97 m)

Armament:
      9 - 6.00" / 152 mm 55.0 cal guns - 115.00lbs / 52.16kg shells, 150 per gun
   Quick firing guns in turret on barbette mounts, 1921 Model
   3 x Triple mounts on centreline ends, majority aft
  1 raised mount aft - superfiring
      Weight of broadside 1,035 lbs / 469 kg
      12 - 21.0" / 533 mm, 20.00 ft / 6.10 m torpedoes - 1.307 t each, 15.683 t total
 In 4 sets of deck mounted carriage/fixed tubes

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 3.00" / 76 mm 400.00 ft / 121.92 m 10.00 ft / 3.05 m
 Ends: Unarmoured
   Main Belt covers 100 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  0.70" / 18 mm 400.00 ft / 121.92 m 22.00 ft / 6.71 m

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

   - Armoured deck - multiple decks: 2.00" / 51 mm For and Aft decks
 Forecastle: 2.00" / 51 mm  Quarter deck: 2.00" / 51 mm

   - Conning towers: Forward 3.00" / 76 mm,  Aft 0.00" / 0 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 144,131 shp / 107,522 Kw = 37.00 kts
 Range 5,400nm at 15.00 kts
 Bunker at max displacement = 1,383 tons

Complement:
 563 - 733

Cost:
 £2.614 million / $10.457 million

Distribution of weights at normal displacement:
 Armament: 308 tons, 2.6 %
    - Guns: 292 tons, 2.5 %
    - Torpedoes: 16 tons, 0.1 %
 Armour: 1,925 tons, 16.4 %
    - Belts: 491 tons, 4.2 %
    - Torpedo bulkhead: 228 tons, 1.9 %
    - Armament: 232 tons, 2.0 %
    - Armour Deck: 941 tons, 8.0 %
    - Conning Tower: 33 tons, 0.3 %
 Machinery: 3,809 tons, 32.4 %
 Hull, fittings & equipment: 4,605 tons, 39.2 %
 Fuel, ammunition & stores: 1,105 tons, 9.4 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   12,227 lbs / 5,546 Kg = 113.2 x 6.0 " / 152 mm shells or 1.6 torpedoes
 Stability (Unstable if below 1.00): 1.11
 Metacentric height 2.7 ft / 0.8 m
 Roll period: 14.8 seconds
 Steadiness - As gun platform (Average = 50 %): 55 %
   - Recoil effect (Restricted arc if above 1.00): 0.39
 Seaboat quality  (Average = 1.00): 1.09

Hull form characteristics:
 Hull has low quarterdeck ,
   an extended bulbous bow and large transom stern
 Block coefficient (normal/deep): 0.525 / 0.532
 Length to Beam Ratio: 10.59 : 1
 'Natural speed' for length: 28.08 kts
 Power going to wave formation at top speed: 63 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 15.00 degrees
 Stern overhang: 0.00 ft / 0.00 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 25.00 %,  30.00 ft / 9.14 m,  26.00 ft / 7.92 m
    - Forward deck: 15.00 %,  26.00 ft / 7.92 m,  26.00 ft / 7.92 m
    - Aft deck: 30.00 %,  26.00 ft / 7.92 m,  26.00 ft / 7.92 m
    - Quarter deck: 30.00 %,  18.00 ft / 5.49 m,  18.00 ft / 5.49 m
    - Average freeboard:  24.00 ft / 7.32 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 175.1 %
  - Above water (accommodation/working, high = better): 218.5 %
 Waterplane Area: 25,263 Square feet or 2,347 Square metres
 Displacement factor (Displacement / loading): 110 %
 Structure weight / hull surface area: 103 lbs/sq ft or 502 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.92
  - Longitudinal: 2.16
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

Wednesday, July 18, 2007

Beyond reason: the GB/CB/1921 Super Fast (42 knots)

The GB/CB/1921 Super Fast is an exercise to understand the limits of what can be achieved with Springsharp 3.0b2 Beta. As usual, to achieve high speed with a large ship, more length is required. One point that interested me was that I was able to reduce the draft to 30 ft. The ship is 37,294 tons standard displacement. An unreasonable number of shafts (8) are required to deliver the thrust. I would think that this is about the fastest large ship that I have been able to achieve, so far. I would attribute that to the latest version of Springsharp. When I do a design, I experiment by adjusting parameters to get the result that I want. This is the Springsharp report:
GB/CB/1921 Super Fast design study, Great Britain Battlecruiser laid down 1921 (Engine 1945)

Displacement:
 35,976 t light; 37,294 t standard; 38,955 t normal; 40,284 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (955.18 ft / 942.00 ft) x 102.00 ft x (30.00 / 30.72 ft)
 (291.14 m / 287.12 m) x 31.09 m  x (9.14 / 9.36 m)

Armament:
      4 - 17.00" / 432 mm 45.0 cal guns - 2,477.44lbs / 1,123.75kg shells, 90 per gun
   Breech loading guns in turret on barbette mounts, 1921 Model
   2 x Twin mounts on centreline, forward deck forward
  1 raised mount - superfiring
      16 - 4.00" / 102 mm 45.0 cal guns - 32.27lbs / 14.64kg shells, 150 per gun
   Quick firing guns in deck and hoist mounts, 1921 Model
   8 x Twin mounts on sides, forward deck aft
  4 raised mounts - superfiring
      Weight of broadside 10,426 lbs / 4,729 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 5.00" / 127 mm 500.00 ft / 152.40 m 12.00 ft / 3.66 m
 Ends: Unarmoured
   Main Belt covers 82 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.00" / 25 mm 500.00 ft / 152.40 m 30.00 ft / 9.14 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 1.00" / 25 mm  2.00" / 51 mm

   - Armoured deck - multiple decks: 2.00" / 51 mm For and Aft decks
 Forecastle: 2.00" / 51 mm  Quarter deck: 2.00" / 51 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 8 shafts, 414,661 shp / 309,337 Kw = 42.00 kts
 Range 5,600nm at 15.00 kts
 Bunker at max displacement = 2,991 tons

Complement:
 1,386 - 1,802

Cost:
 £9.414 million / $37.658 million

Distribution of weights at normal displacement:
 Armament: 1,684 tons, 4.3 %
 Armour: 5,367 tons, 13.8 %
    - Belts: 1,287 tons, 3.3 %
    - Torpedo bulkhead: 555 tons, 1.4 %
    - Armament: 1,108 tons, 2.8 %
    - Armour Deck: 2,417 tons, 6.2 %
 Machinery: 10,471 tons, 26.9 %
 Hull, fittings & equipment: 18,454 tons, 47.4 %
 Fuel, ammunition & stores: 2,979 tons, 7.6 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   43,446 lbs / 19,707 Kg = 17.7 x 17.0 " / 432 mm shells or 4.4 torpedoes
 Stability (Unstable if below 1.00): 1.17
 Metacentric height 6.9 ft / 2.1 m
 Roll period: 16.3 seconds
 Steadiness - As gun platform (Average = 50 %): 52 %
   - Recoil effect (Restricted arc if above 1.00): 0.57
 Seaboat quality  (Average = 1.00): 1.03

Hull form characteristics:
 Hull has a flush deck,
   an extended bulbous bow and large transom stern
 Block coefficient (normal/deep): 0.473 / 0.478
 Length to Beam Ratio: 9.24 : 1
 'Natural speed' for length: 35.37 kts
 Power going to wave formation at top speed: 59 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 15.00 degrees
 Stern overhang: 3.00 ft / 0.91 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 38.00 %,  38.00 ft / 11.58 m,  31.00 ft / 9.45 m
    - Forward deck: 30.00 %,  31.00 ft / 9.45 m,  31.00 ft / 9.45 m
    - Aft deck: 7.00 %,  31.00 ft / 9.45 m,  31.00 ft / 9.45 m
    - Quarter deck: 25.00 %,  31.00 ft / 9.45 m,  31.00 ft / 9.45 m
    - Average freeboard:  32.06 ft / 9.77 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 136.4 %
  - Above water (accommodation/working, high = better): 276.7 %
 Waterplane Area: 64,949 Square feet or 6,034 Square metres
 Displacement factor (Displacement / loading): 109 %
 Structure weight / hull surface area: 194 lbs/sq ft or 948 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

Tuesday, July 17, 2007

For large, fast ships, length is critical

I often forget this lesson, but I quickly relearn it: large fast ships need adequate length for a variety of reasons (at least in Springsharp). Length decreases the power required and enhances seakeeping. That alone is sufficient reason to go long. I have this design for the GB/CB/1921 Fast, that is not as fast as I would like, but it seems sufficient for now. The GB/CB/1921 has 9-14in/55 guns, 16-5.5in QF guns, 6-4.7in AA guns, and 24-2pdr pompoms. I really don't understand why the protection is rated as well as it is by Springsharp:
GB/CB/1921 Fast, Great Britain Battlecruiser laid down 1921 (Engine 1937)

Displacement:
 39,798 t light; 41,757 t standard; 45,708 t normal; 48,868 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (886.65 ft / 874.00 ft) x 104.00 ft x (32.00 / 33.70 ft)
 (270.25 m / 266.40 m) x 31.70 m  x (9.75 / 10.27 m)

Armament:
      9 - 14.00" / 356 mm 55.0 cal guns - 1,485.00lbs / 673.58kg shells, 120 per gun
   Breech loading guns in turret on barbette mounts, 1921 Model
   2 x Triple mounts on centreline, forward deck forward
  3 raised mounts
   1 x Triple mount on centreline, aft deck forward
      16 - 5.50" / 140 mm 55.0 cal guns - 90.00lbs / 40.82kg shells, 150 per gun
   Quick firing guns in turret on barbette mounts, 1921 Model
   8 x Single mounts on sides, forward deck aft
  4 raised mounts - superfiring
      6 - 4.70" / 119 mm 50.0 cal guns - 54.96lbs / 24.93kg shells, 150 per gun
   Anti-air guns in deck and hoist mounts, 1921 Model
   6 x Single mounts on sides, forward deck aft
  6 raised mounts
      24 - 1.57" / 40.0 mm 45.0 cal guns - 1.97lbs / 0.89kg shells, 250 per gun
   Anti-air guns in deck mounts, 1921 Model
   6 x 2 row quad mounts on sides, evenly spread
  6 raised mounts
      Weight of broadside 15,182 lbs / 6,886 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 6.00" / 152 mm 560.00 ft / 170.69 m 8.00 ft / 2.44 m
 Ends: Unarmoured
 Upper: 4.00" / 102 mm 560.00 ft / 170.69 m 8.00 ft / 2.44 m
   Main Belt covers 99 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  2.00" / 51 mm 560.00 ft / 170.69 m 32.00 ft / 9.75 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 8.00" / 203 mm 5.00" / 127 mm  8.00" / 203 mm
 2nd: 4.00" / 102 mm 3.00" / 76 mm  4.00" / 102 mm

   - Armoured deck - multiple decks: 3.00" / 76 mm For and Aft decks
 Forecastle: 3.00" / 76 mm  Quarter deck: 3.00" / 76 mm

   - Conning towers: Forward 8.00" / 203 mm,  Aft 0.00" / 0 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 286,346 shp / 213,614 Kw = 36.00 kts
 Range 8,500nm at 18.00 kts
 Bunker at max displacement = 7,111 tons

Complement:
 1,562 - 2,031

Cost:
 £10.761 million / $43.045 million

Distribution of weights at normal displacement:
 Armament: 3,382 tons, 7.4 %
 Armour: 9,923 tons, 21.7 %
    - Belts: 1,888 tons, 4.1 %
    - Torpedo bulkhead: 1,326 tons, 2.9 %
    - Armament: 2,856 tons, 6.2 %
    - Armour Deck: 3,632 tons, 7.9 %
    - Conning Tower: 220 tons, 0.5 %
 Machinery: 7,936 tons, 17.4 %
 Hull, fittings & equipment: 18,556 tons, 40.6 %
 Fuel, ammunition & stores: 5,910 tons, 12.9 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   58,064 lbs / 26,337 Kg = 42.3 x 14.0 " / 356 mm shells or 7.1 torpedoes
 Stability (Unstable if below 1.00): 1.08
 Metacentric height 6.2 ft / 1.9 m
 Roll period: 17.6 seconds
 Steadiness - As gun platform (Average = 50 %): 52 %
   - Recoil effect (Restricted arc if above 1.00): 0.82
 Seaboat quality  (Average = 1.00): 1.03

Hull form characteristics:
 Hull has low quarterdeck ,
   an extended bulbous bow and small transom stern
 Block coefficient (normal/deep): 0.550 / 0.558
 Length to Beam Ratio: 8.40 : 1
 'Natural speed' for length: 31.87 kts
 Power going to wave formation at top speed: 57 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 15.00 degrees
 Stern overhang: 3.00 ft / 0.91 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 25.00 %,  36.00 ft / 10.97 m,  30.00 ft / 9.14 m
    - Forward deck: 30.00 %,  30.00 ft / 9.14 m,  30.00 ft / 9.14 m
    - Aft deck: 20.00 %,  30.00 ft / 9.14 m,  30.00 ft / 9.14 m
    - Quarter deck: 25.00 %,  22.00 ft / 6.71 m,  22.00 ft / 6.71 m
    - Average freeboard:  28.60 ft / 8.72 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 112.1 %
  - Above water (accommodation/working, high = better): 237.8 %
 Waterplane Area: 64,999 Square feet or 6,039 Square metres
 Displacement factor (Displacement / loading): 108 %
 Structure weight / hull surface area: 210 lbs/sq ft or 1,023 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.96
  - Longitudinal: 1.44
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

Monday, July 16, 2007

A GB/CA/1921 design

This is my first attempt at a GB/CA/1921 design in Springsharp 3.0b2 Beta. I want a fast ship that is well-protected and which can fill the armoured cruiser role for the 1921 building program. For the size, the 9-9.2in/55 guns seem rather meager, but 10in guns seem to heavy and slow-firing. Still, the ship is large, with a 22,474 tons Standard displacement. The belt is 8in at the waterline and the deck is 3in. I want speed, so I made the sacrifices necessary to obtain a 33 knot speed and a range of 12,000nm at 16 knots. All that costs size. This is the Springsharp report:
GB/CA/1921, Great Britain Heavy Cruiser laid down 1921 (Engine 1927)

Displacement:
 21,612 t light; 22,474 t standard; 25,832 t normal; 28,518 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (721.59 ft / 715.00 ft) x 90.00 ft x (25.00 / 27.02 ft)
 (219.94 m / 217.93 m) x 27.43 m  x (7.62 / 8.24 m)

Armament:
      9 - 9.20" / 234 mm 55.0 cal guns - 420.00lbs / 190.51kg shells, 150 per gun
   Breech loading guns in turret on barbette mounts, 1921 Model
   3 x Single mounts on centreline ends, majority forward
  1 raised mount - superfiring
      6 - 4.70" / 119 mm 50.0 cal guns - 54.96lbs / 24.93kg shells, 150 per gun
   Anti-air guns in deck and hoist mounts, 1921 Model
   6 x Single mounts on sides, forward deck aft
  6 raised mounts
      16 - 1.57" / 40.0 mm 50.0 cal guns - 2.00lbs / 0.91kg shells, 150 per gun
   Anti-air guns in deck mounts, 1921 Model
   4 x 2 row quad mounts on sides, aft deck forward
      Weight of broadside 4,142 lbs / 1,879 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 8.00" / 203 mm 470.00 ft / 143.26 m 8.00 ft / 2.44 m
 Ends: Unarmoured
 Upper: 5.00" / 127 mm 470.00 ft / 143.26 m 8.00 ft / 2.44 m
   Main Belt covers 101 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.50" / 38 mm 470.00 ft / 143.26 m 25.00 ft / 7.62 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 8.00" / 203 mm 6.00" / 152 mm  8.00" / 203 mm

   - Armoured deck - multiple decks: 3.00" / 76 mm For and Aft decks
 Forecastle: 3.00" / 76 mm  Quarter deck: 3.00" / 76 mm

   - Conning towers: Forward 8.00" / 203 mm,  Aft 0.00" / 0 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 156,007 shp / 116,381 Kw = 33.00 kts
 Range 12,000nm at 16.00 kts
 Bunker at max displacement = 6,045 tons

Complement:
 1,018 - 1,324

Cost:
 £4.877 million / $19.506 million

Distribution of weights at normal displacement:
 Armament: 1,396 tons, 5.4 %
 Armour: 6,657 tons, 25.8 %
    - Belts: 2,068 tons, 8.0 %
    - Torpedo bulkhead: 652 tons, 2.5 %
    - Armament: 1,184 tons, 4.6 %
    - Armour Deck: 2,602 tons, 10.1 %
    - Conning Tower: 151 tons, 0.6 %
 Machinery: 4,924 tons, 19.1 %
 Hull, fittings & equipment: 8,634 tons, 33.4 %
 Fuel, ammunition & stores: 4,220 tons, 16.3 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   41,886 lbs / 18,999 Kg = 107.6 x 9.2 " / 234 mm shells or 5.6 torpedoes
 Stability (Unstable if below 1.00): 1.29
 Metacentric height 6.7 ft / 2.0 m
 Roll period: 14.6 seconds
 Steadiness - As gun platform (Average = 50 %): 55 %
   - Recoil effect (Restricted arc if above 1.00): 0.25
 Seaboat quality  (Average = 1.00): 1.09

Hull form characteristics:
 Hull has a flush deck,
   an extended bulbous bow and small transom stern
 Block coefficient (normal/deep): 0.562 / 0.574
 Length to Beam Ratio: 7.94 : 1
 'Natural speed' for length: 28.88 kts
 Power going to wave formation at top speed: 58 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 12.00 degrees
 Stern overhang: 0.00 ft / 0.00 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 30.00 %,  31.00 ft / 9.45 m,  26.00 ft / 7.92 m
    - Forward deck: 30.00 %,  26.00 ft / 7.92 m,  24.00 ft / 7.32 m
    - Aft deck: 25.00 %,  24.00 ft / 7.32 m,  24.00 ft / 7.32 m
    - Quarter deck: 15.00 %,  24.00 ft / 7.32 m,  24.00 ft / 7.32 m
    - Average freeboard:  25.50 ft / 7.77 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 101.7 %
  - Above water (accommodation/working, high = better): 213.8 %
 Waterplane Area: 46,545 Square feet or 4,324 Square metres
 Displacement factor (Displacement / loading): 123 %
 Structure weight / hull surface area: 142 lbs/sq ft or 693 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.97
  - Longitudinal: 1.35
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is adequate
 Room for accommodation and workspaces is excellent

Sunday, July 15, 2007

The GB/BB/1912 design study

My friend Cliff ultimately decided to build a more heavily armed ship in 1912, in our game. He toyed with a more lightly-armed fast battleship, instead: the GB/BB/1912. I had thought this was an earlier design, but the sketch design is clearly marked as 1912. This is the original specification:
1912  29,000 tons  9-12in/50, 8-6in QF guns
13in belt  24-25 knots  650ft x 100ft x 28.7ft
Cp=0.56  Cm=0.97
80,000 SHP @16 SHP/ton  100,000 SHP Max.
Mach =  5,000 tons
Hull = 12,180 tons
Misc =  2,340 tons
Arm  =  1,345 tons
Prot =  8,180 tons

29,045 tons Standard
 4,000 tons oil fuel
33,045 tons full load

We typically either were over optimistic or over specified our designs. You can see the result in the Springsharp 3.0b2 Beta result:
GB/BB/1912 design study, Great Britain Battleship laid down 1912

Displacement:
 24,879 t light; 26,101 t standard; 29,848 t normal; 32,846 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (653.00 ft / 650.00 ft) x 100.00 ft x (28.70 / 30.99 ft)
 (199.03 m / 198.12 m) x 30.48 m  x (8.75 / 9.45 m)

Armament:
      9 - 12.00" / 305 mm 50.0 cal guns - 914.66lbs / 414.88kg shells, 120 per gun
   Breech loading guns in turret on barbette mounts, 1912 Model
   3 x Triple mounts on centreline ends, majority forward
  1 raised mount - superfiring
      8 - 6.00" / 152 mm 50.0 cal guns - 114.33lbs / 51.86kg shells, 150 per gun
   Quick firing guns in deck and hoist mounts, 1912 Model
   8 x Single mounts on sides amidships
      Weight of broadside 9,147 lbs / 4,149 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 13.0" / 330 mm 390.00 ft / 118.87 m 8.00 ft / 2.44 m
 Ends: Unarmoured
 Upper: 9.00" / 229 mm 390.00 ft / 118.87 m 8.00 ft / 2.44 m
   Main Belt covers 92 % of normal length

   - Torpedo Bulkhead:
  2.00" / 51 mm 390.00 ft / 118.87 m 28.70 ft / 8.75 m

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

   - Armoured deck - multiple decks: 3.00" / 76 mm For and Aft decks
 Forecastle: 3.00" / 76 mm  Quarter deck: 3.00" / 76 mm

   - Conning towers: Forward 13.00" / 330 mm,  Aft 0.00" / 0 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 78,876 shp / 58,842 Kw = 26.25 kts
 Range 6,500nm at 18.00 kts
 Bunker at max displacement = 6,745 tons

Complement:
 1,135 - 1,476

Cost:
 £2.261 million / $9.043 million

Distribution of weights at normal displacement:
 Armament: 1,896 tons, 6.4 %
 Armour: 9,142 tons, 30.6 %
    - Belts: 3,036 tons, 10.2 %
    - Torpedo bulkhead: 828 tons, 2.8 %
    - Armament: 2,448 tons, 8.2 %
    - Armour Deck: 2,560 tons, 8.6 %
    - Conning Tower: 269 tons, 0.9 %
 Machinery: 3,145 tons, 10.5 %
 Hull, fittings & equipment: 10,696 tons, 35.8 %
 Fuel, ammunition & stores: 4,969 tons, 16.6 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   54,373 lbs / 24,663 Kg = 62.9 x 12.0 " / 305 mm shells or 8.9 torpedoes
 Stability (Unstable if below 1.00): 1.21
 Metacentric height 7.1 ft / 2.2 m
 Roll period: 15.8 seconds
 Steadiness - As gun platform (Average = 50 %): 76 %
   - Recoil effect (Restricted arc if above 1.00): 0.51
 Seaboat quality  (Average = 1.00): 1.52

Hull form characteristics:
 Hull has rise forward of midbreak,
   a ram bow and a cruiser stern
 Block coefficient (normal/deep): 0.560 / 0.571
 Length to Beam Ratio: 6.50 : 1
 'Natural speed' for length: 25.50 kts
 Power going to wave formation at top speed: 51 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): -3.00 degrees
 Stern overhang: -3.00 ft / -0.91 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 30.00 %,  29.00 ft / 8.84 m,  28.00 ft / 8.53 m
    - Forward deck: 37.00 %,  28.00 ft / 8.53 m,  28.00 ft / 8.53 m
    - Aft deck: 18.00 %,  20.00 ft / 6.10 m,  20.00 ft / 6.10 m
    - Quarter deck: 15.00 %,  20.00 ft / 6.10 m,  20.00 ft / 6.10 m
    - Average freeboard:  25.48 ft / 7.77 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 79.7 %
  - Above water (accommodation/working, high = better): 195.0 %
 Waterplane Area: 45,790 Square feet or 4,254 Square metres
 Displacement factor (Displacement / loading): 122 %
 Structure weight / hull surface area: 175 lbs/sq ft or 853 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.93
  - Longitudinal: 1.85
  - 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
 Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Saturday, July 14, 2007

The original concept for the Ger/CB/1906 battlecruisers

Springsharp 3.0b2 works well for recreating the original concept for our early 1970's designs. The Ger/CB/1906 ships were intended to have inclined armour, so this is a natural for the new Springsharp. This is the original specification:
Scharnhorst class
800ft x 85ft x 25.6ft
Cp = 0.53
Cm = 0.95
120,000 SHP = 33 knots (Max. 36 knots on overload)
8-12in/45 BLR
12-4in QF guns
4in belt
3in deck
6in turrets and barbettes
Displacement=25,000 tons (Standard)
Hull=11,250 tons
Mach= 8,580 tons
Arm=    955 tons
Misc= 2,000 tons
Prot= 2,215 tons

This is a photograph of one of the two ships:

The 120,000 SHP for 33 knots was over-optimistic. 120,000 SHP is only good for 30 knots, which was fast for the time. This is the Springsharp report:
Ger/CB/1906 Original Concept, Germany Battlecruiser laid down 1906

Displacement:
 24,778 t light; 25,733 t standard; 28,599 t normal; 30,892 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (803.00 ft / 800.00 ft) x 85.00 ft x (25.60 / 27.25 ft)
 (244.75 m / 243.84 m) x 25.91 m  x (7.80 / 8.31 m)

Armament:
      8 - 12.00" / 305 mm 45.0 cal guns - 871.37lbs / 395.24kg shells, 90 per gun
   Breech loading guns in turret on barbette mounts, 1906 Model
   4 x Single mounts on centreline ends, evenly spread
  2 raised mounts - superfiring
      12 - 4.00" / 102 mm 50.0 cal guns - 33.88lbs / 15.37kg shells, 150 per gun
   Quick firing guns in deck and hoist mounts, 1906 Model
   12 x Single mounts on sides, evenly spread
      Weight of broadside 7,377 lbs / 3,346 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 4.00" / 102 mm 425.00 ft / 129.54 m 16.00 ft / 4.88 m
 Ends: Unarmoured
   Main Belt covers 82 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.50" / 38 mm 425.00 ft / 129.54 m 25.60 ft / 7.80 m

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

   - Armoured deck - multiple decks: 3.00" / 76 mm For and Aft decks

   - Conning towers: Forward 6.00" / 152 mm,  Aft 0.00" / 0 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 119,660 shp / 89,266 Kw = 30.20 kts
 Range 5,600nm at 15.00 kts
 Bunker at max displacement = 5,159 tons

Complement:
 1,099 - 1,429

Cost:
 £2.649 million / $10.598 million

Distribution of weights at normal displacement:
 Armament: 1,648 tons, 5.8 %
 Armour: 5,190 tons, 18.1 %
    - Belts: 1,169 tons, 4.1 %
    - Torpedo bulkhead: 604 tons, 2.1 %
    - Armament: 1,401 tons, 4.9 %
    - Armour Deck: 1,895 tons, 6.6 %
    - Conning Tower: 121 tons, 0.4 %
 Machinery: 7,770 tons, 27.2 %
 Hull, fittings & equipment: 10,171 tons, 35.6 %
 Fuel, ammunition & stores: 3,820 tons, 13.4 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   28,273 lbs / 12,825 Kg = 32.7 x 12.0 " / 305 mm shells or 3.2 torpedoes
 Stability (Unstable if below 1.00): 1.21
 Metacentric height 5.5 ft / 1.7 m
 Roll period: 15.2 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 rise forward of midbreak,
   a ram bow and a cruiser stern
 Block coefficient (normal/deep): 0.575 / 0.583
 Length to Beam Ratio: 9.41 : 1
 'Natural speed' for length: 28.28 kts
 Power going to wave formation at top speed: 48 %
 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 (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 35.00 %,  34.00 ft / 10.36 m,  27.00 ft / 8.23 m
    - Forward deck: 37.00 %,  27.00 ft / 8.23 m,  26.00 ft / 7.92 m
    - Aft deck: 13.00 %,  18.00 ft / 5.49 m,  18.00 ft / 5.49 m
    - Quarter deck: 15.00 %,  18.00 ft / 5.49 m,  19.00 ft / 5.79 m
    - Average freeboard:  25.35 ft / 7.73 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 143.8 %
  - Above water (accommodation/working, high = better): 204.5 %
 Waterplane Area: 48,583 Square feet or 4,514 Square metres
 Displacement factor (Displacement / loading): 105 %
 Structure weight / hull surface area: 151 lbs/sq ft or 737 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.99
  - Longitudinal: 1.05
  - 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

Friday, July 13, 2007

The original concept for the Ger/CB/1905 battlecruiser in Springsharp 3.0b2 Beta

Springsharp 3.0b2 Beta is a great improvement, even over the last beta version. The next design in the "Blue Book" is the original concept for the Ger/CB/1905 design. This is a light battlecruiser with 4-12in/45 and 12-4in QF guns. The armour basis is 4in with 3in+1in decks. The torpedo bulkhead is 2in. The turret faces are 9in and the barbettes, at their thickest point, are 8in. The speed is 31 knots and I have used a range of 7.500nm at 18 knots. This is a photograph of the one ship built, the Blücher:

This is the Springsharp report:
Ger/CB/1905 Original Concept, Germany Battlecruiser laid down 1905 (Engine 1912)

Displacement:
 18,475 t light; 19,136 t standard; 22,760 t normal; 25,660 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (703.00 ft / 700.00 ft) x 80.00 ft x (24.40 / 26.92 ft)
 (214.27 m / 213.36 m) x 24.38 m  x (7.44 / 8.20 m)

Armament:
      4 - 12.00" / 305 mm 45.0 cal guns - 871.00lbs / 395.08kg shells, 90 per gun
   Breech loading guns in turret on barbette mounts, 1905 Model
   2 x Twin mounts on centreline ends, evenly spread
      12 - 4.00" / 102 mm 45.0 cal guns - 32.27lbs / 14.64kg shells, 150 per gun
   Quick firing guns in casemate mounts, 1905 Model
   12 x Single mounts on sides amidships
      Weight of broadside 3,871 lbs / 1,756 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 4.00" / 102 mm 380.00 ft / 115.82 m 8.00 ft / 2.44 m
 Ends: Unarmoured
 Upper: 4.00" / 102 mm 380.00 ft / 115.82 m 8.00 ft / 2.44 m
   Main Belt covers 84 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  2.00" / 51 mm 380.00 ft / 115.82 m 24.40 ft / 7.44 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 9.00" / 229 mm 4.00" / 102 mm  8.00" / 203 mm
 2nd: 4.00" / 102 mm 3.00" / 76 mm  4.00" / 102 mm

   - Armoured deck - multiple decks: 4.00" / 102 mm For and Aft decks
 Forecastle: 3.00" / 76 mm  Quarter deck: 3.00" / 76 mm

   - Conning towers: Forward 9.00" / 229 mm,  Aft 0.00" / 0 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 122,269 shp / 91,213 Kw = 31.00 kts
 Range 7,500nm at 18.00 kts
 Bunker at max displacement = 6,523 tons

Complement:
 926 - 1,204

Cost:
 £1.673 million / $6.693 million

Distribution of weights at normal displacement:
 Armament: 689 tons, 3.0 %
 Armour: 5,400 tons, 23.7 %
    - Belts: 1,049 tons, 4.6 %
    - Torpedo bulkhead: 686 tons, 3.0 %
    - Armament: 699 tons, 3.1 %
    - Armour Deck: 2,810 tons, 12.3 %
    - Conning Tower: 156 tons, 0.7 %
 Machinery: 4,875 tons, 21.4 %
 Hull, fittings & equipment: 7,511 tons, 33.0 %
 Fuel, ammunition & stores: 4,286 tons, 18.8 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   33,961 lbs / 15,405 Kg = 39.3 x 12.0 " / 305 mm shells or 4.4 torpedoes
 Stability (Unstable if below 1.00): 1.35
 Metacentric height 6.1 ft / 1.8 m
 Roll period: 13.6 seconds
 Steadiness - As gun platform (Average = 50 %): 63 %
   - Recoil effect (Restricted arc if above 1.00): 0.29
 Seaboat quality  (Average = 1.00): 1.27

Hull form characteristics:
 Hull has rise forward of midbreak,
   a ram bow and a cruiser stern
 Block coefficient (normal/deep): 0.583 / 0.596
 Length to Beam Ratio: 8.75 : 1
 'Natural speed' for length: 26.46 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: -3.00 ft / -0.91 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 30.00 %,  29.00 ft / 8.84 m,  26.00 ft / 7.92 m
    - Forward deck: 33.00 %,  26.00 ft / 7.92 m,  26.00 ft / 7.92 m
    - Aft deck: 22.00 %,  18.00 ft / 5.49 m,  18.00 ft / 5.49 m
    - Quarter deck: 15.00 %,  18.00 ft / 5.49 m,  18.00 ft / 5.49 m
    - Average freeboard:  23.40 ft / 7.13 m
 Ship tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 111.6 %
  - Above water (accommodation/working, high = better): 189.1 %
 Waterplane Area: 40,311 Square feet or 3,745 Square metres
 Displacement factor (Displacement / loading): 124 %
 Structure weight / hull surface area: 129 lbs/sq ft or 632 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.98
  - Longitudinal: 1.24
  - 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

So, how heavy would a cannon ball for an 11in Dahlgren be?

Probably, no one but me worries about such things, but I wondered how heavy the cannon ball was for an 11in smoothbore Dahlgren gun, such as used by the USS Monitor in 1862. I have an empirical formula for cannon balls from the "Age of Sail". This is the formula:
Shot weight = (gun bore in inches)^3 / 8

For an 11in gun, that gives a shot weight of 166-3/8 lbs. For comparison, a smoothbore 32pdr would have a bore of about 6.35 inches. While my system is inexact, it gives a rough idea of the relationship between bore size and cannon ball weight. For stone shot, the divisor is 22. The shot weight of an a nominally 8 inch stone gun shot would be 24 lbs, but this this actually requires a slightly larger bore of 8.08 inches. This is not a large difference, but enough to matter. You might ask why my interest? For one, I have an Old Dominion University College of Sciences calendar in my cube, and the picture for June was of a professor standing next to a Dalhgren gun that they had raised from the wreck of the Monitor.

Thursday, July 12, 2007

In Springsharp 3.0b2, the original concept for the Ger/BB/1905 works great

I had this idea for a rather fast German battleship, to be laid down in 1905, that would carry 8-12in/45 BLR and 12-4in QF guns. The speed was to be 23 knots, the armour basis 11in and the decks 3in+1in. In Springsharp 3.0b2 Beta, the ship works well. The original idea was to have a Standard Displacement of 22,000 tons. My design is 21,765 tons Standard. This is a photograph of one of the ships:

This is the Springsharp report:
Ger/BB/1905 Original Concept, Germany Battleship laid down 1905

Displacement:
 20,662 t light; 21,765 t standard; 24,517 t normal; 26,719 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (585.00 ft / 580.00 ft) x 90.00 ft x (26.60 / 28.58 ft)
 (178.31 m / 176.78 m) x 27.43 m  x (8.11 / 8.71 m)

Armament:
      8 - 12.00" / 305 mm 45.0 cal guns - 871.00lbs / 395.08kg shells, 150 per gun
   Breech loading guns in turret on barbette mounts, 1905 Model
   4 x Twin mounts on centreline ends, evenly spread
  2 raised mounts - superfiring
      12 - 4.00" / 102 mm 45.0 cal guns - 32.27lbs / 14.64kg shells, 150 per gun
   Quick firing guns in casemate mounts, 1905 Model
   12 x Single mounts on sides, evenly spread
      Weight of broadside 7,355 lbs / 3,336 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 10.0" / 254 mm 380.00 ft / 115.82 m 8.00 ft / 2.44 m
 Ends: 4.00" / 102 mm 150.00 ft / 45.72 m 8.00 ft / 2.44 m
   50.00 ft / 15.24 m Unarmoured ends
 Upper: 7.00" / 178 mm 380.00 ft / 115.82 m 8.00 ft / 2.44 m
   Main Belt covers 101 % of normal length

   - Torpedo Bulkhead:
  2.00" / 51 mm 380.00 ft / 115.82 m 26.60 ft / 8.11 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 11.0" / 279 mm 6.00" / 152 mm  11.0" / 279 mm
 2nd: 4.00" / 102 mm 4.00" / 102 mm  4.00" / 102 mm

   - Armoured deck - multiple decks: 4.00" / 102 mm For and Aft decks
 Forecastle: 3.00" / 76 mm  Quarter deck: 3.00" / 76 mm

   - Conning towers: Forward 11.00" / 279 mm,  Aft 0.00" / 0 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 44,328 shp / 33,069 Kw = 23.00 kts
 Range 5,600nm at 15.00 kts
 Bunker at max displacement = 4,954 tons

Complement:
 979 - 1,273

Cost:
 £1.863 million / $7.451 million

Distribution of weights at normal displacement:
 Armament: 1,308 tons, 5.3 %
 Armour: 7,961 tons, 32.5 %
    - Belts: 2,433 tons, 9.9 %
    - Torpedo bulkhead: 748 tons, 3.1 %
    - Armament: 1,872 tons, 7.6 %
    - Armour Deck: 2,708 tons, 11.0 %
    - Conning Tower: 200 tons, 0.8 %
 Machinery: 3,358 tons, 13.7 %
 Hull, fittings & equipment: 8,034 tons, 32.8 %
 Fuel, ammunition & stores: 3,855 tons, 15.7 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   38,591 lbs / 17,505 Kg = 44.7 x 12.0 " / 305 mm shells or 6.1 torpedoes
 Stability (Unstable if below 1.00): 1.23
 Metacentric height 6.2 ft / 1.9 m
 Roll period: 15.2 seconds
 Steadiness - As gun platform (Average = 50 %): 80 %
   - Recoil effect (Restricted arc if above 1.00): 0.57
 Seaboat quality  (Average = 1.00): 1.61

Hull form characteristics:
 Hull has rise forward of midbreak,
   a ram bow and a cruiser stern
 Block coefficient (normal/deep): 0.618 / 0.627
 Length to Beam Ratio: 6.44 : 1
 'Natural speed' for length: 24.08 kts
 Power going to wave formation at top speed: 49 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 0.00 degrees
 Stern overhang: -2.00 ft / -0.61 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 30.00 %,  27.00 ft / 8.23 m,  25.00 ft / 7.62 m
    - Forward deck: 37.00 %,  25.00 ft / 7.62 m,  25.00 ft / 7.62 m
    - Aft deck: 18.00 %,  17.00 ft / 5.18 m,  17.00 ft / 5.18 m
    - Quarter deck: 15.00 %,  17.00 ft / 5.18 m,  17.00 ft / 5.18 m
    - Average freeboard:  22.60 ft / 6.89 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 90.8 %
  - Above water (accommodation/working, high = better): 169.1 %
 Waterplane Area: 38,824 Square feet or 3,607 Square metres
 Displacement factor (Displacement / loading): 116 %
 Structure weight / hull surface area: 155 lbs/sq ft or 757 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.94
  - Longitudinal: 1.68
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is adequate
 Room for accommodation and workspaces is excellent
 Ship has slow, easy roll, a good, steady gun platform
 Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Wednesday, July 11, 2007

The Ger/BB/1907 design

The Ger/BB/1907 design actually came out lighter in Springsharp 3.0b2 than originally designed. The power to reach 24 knots is almost exactly right in my 1971 design, at 54,000 SHP, when Springsharp asks for 52,180 SHP. That is lower due to the displacement being less for the specified armament, armour, and speed. The idea was to have a 24 knot ship with 8-12in/50 BLR and 12-4in QF guns. The belt was 8in/13in, while the decks were 3in+1in. This is the Springsharp report:
Ger/BB/1907, Germany Battleship laid down 1907

Displacement:
 21,982 t light; 23,022 t standard; 25,921 t normal; 28,240 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (622.00 ft / 620.00 ft) x 105.00 ft x (26.00 / 27.81 ft)
 (189.59 m / 188.98 m) x 32.00 m  x (7.92 / 8.48 m)

Armament:
      8 - 12.00" / 305 mm 50.0 cal guns - 915.00lbs / 415.04kg shells, 120 per gun
   Breech loading guns in turret on barbette mounts, 1907 Model
   4 x Twin mounts on centreline ends, evenly spread
  2 raised mounts - superfiring
      12 - 4.00" / 102 mm 50.0 cal guns - 33.88lbs / 15.37kg shells, 150 per gun
   Quick firing guns in deck and hoist mounts, 1907 Model
   12 x Single mounts on sides amidships
      Weight of broadside 7,727 lbs / 3,505 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 13.0" / 330 mm 330.00 ft / 100.58 m 8.00 ft / 2.44 m
 Ends: Unarmoured
 Upper: 8.00" / 203 mm 330.00 ft / 100.58 m 8.00 ft / 2.44 m
   Main Belt covers 82 % of normal length

   - Torpedo Bulkhead:
  2.00" / 51 mm 330.00 ft / 100.58 m 26.00 ft / 7.92 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 13.0" / 330 mm 8.00" / 203 mm  10.0" / 254 mm
 2nd: 3.00" / 76 mm 2.00" / 51 mm  4.00" / 102 mm

   - Armoured deck - multiple decks: 4.00" / 102 mm For and Aft decks

   - Conning towers: Forward 10.00" / 254 mm,  Aft 0.00" / 0 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 52,180 shp / 38,926 Kw = 24.00 kts
 Range 6,500nm at 15.00 kts
 Bunker at max displacement = 5,218 tons

Complement:
 1,020 - 1,327

Cost:
 £1.987 million / $7.948 million

Distribution of weights at normal displacement:
 Armament: 1,570 tons, 6.1 %
 Armour: 7,920 tons, 30.6 %
    - Belts: 2,565 tons, 9.9 %
    - Torpedo bulkhead: 635 tons, 2.4 %
    - Armament: 1,931 tons, 7.4 %
    - Armour Deck: 2,601 tons, 10.0 %
    - Conning Tower: 189 tons, 0.7 %
 Machinery: 2,965 tons, 11.4 %
 Hull, fittings & equipment: 9,527 tons, 36.8 %
 Fuel, ammunition & stores: 3,939 tons, 15.2 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   47,597 lbs / 21,589 Kg = 55.1 x 12.0 " / 305 mm shells or 8.2 torpedoes
 Stability (Unstable if below 1.00): 1.32
 Metacentric height 8.8 ft / 2.7 m
 Roll period: 14.8 seconds
 Steadiness - As gun platform (Average = 50 %): 78 %
   - Recoil effect (Restricted arc if above 1.00): 0.34
 Seaboat quality  (Average = 1.00): 1.56

Hull form characteristics:
 Hull has rise forward of midbreak,
   a ram bow and a cruiser stern
 Block coefficient (normal/deep): 0.536 / 0.546
 Length to Beam Ratio: 5.90 : 1
 'Natural speed' for length: 24.90 kts
 Power going to wave formation at top speed: 48 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): -2.00 degrees
 Stern overhang: -3.00 ft / -0.91 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 25.00 %,  29.00 ft / 8.84 m,  26.00 ft / 7.92 m
    - Forward deck: 33.00 %,  26.00 ft / 7.92 m,  26.00 ft / 7.92 m
    - Aft deck: 27.00 %,  18.00 ft / 5.49 m,  18.00 ft / 5.49 m
    - Quarter deck: 15.00 %,  18.00 ft / 5.49 m,  18.00 ft / 5.49 m
    - Average freeboard:  22.94 ft / 6.99 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 81.4 %
  - Above water (accommodation/working, high = better): 187.6 %
 Waterplane Area: 44,841 Square feet or 4,166 Square metres
 Displacement factor (Displacement / loading): 121 %
 Structure weight / hull surface area: 168 lbs/sq ft or 818 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.94
  - Longitudinal: 1.67
  - 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
 Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Tuesday, July 10, 2007

The Ger/BB/1909 design in Springsharp 3.0b2 Beta

I just tried the Ger/BB/1909 in the lastest version of Springsharp, 3.0b2 Beta. The machinery, for the planned 60,000 SHP is lighter than I had expected and the protection is heavier. The speed as designed was 23 knots, but 60,000 SHP is good for 23.7 knots. The armament includes 9-12in/50 BLR and 8-6in QF guns. the armour basis is 14in, with 6in and 4in deck armour, although so far, it has to be lumped as 10 inches of deck armour. This is the Springsharp report:
Ger/BB/1909, Germany Battleship laid down 1909

Displacement:
 28,885 t light; 30,228 t standard; 35,865 t normal; 40,375 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (645.00 ft / 645.00 ft) x 106.00 ft x (30.00 / 33.12 ft)
 (196.60 m / 196.60 m) x 32.31 m  x (9.14 / 10.10 m)

Armament:
      9 - 12.00" / 305 mm 50.0 cal guns - 915.00lbs / 415.04kg shells, 120 per gun
   Breech loading guns in turret on barbette mounts, 1909 Model
   3 x Triple mounts on centreline ends, majority forward
  1 raised mount - superfiring
      8 - 6.00" / 152 mm 50.0 cal guns - 114.00lbs / 51.71kg shells, 150 per gun
   Quick firing guns in deck and hoist mounts, 1909 Model
   8 x Single mounts on sides amidships
      Weight of broadside 9,147 lbs / 4,149 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 14.0" / 356 mm 375.00 ft / 114.30 m 12.00 ft / 3.66 m
 Ends: Unarmoured
   Main Belt covers 89 % of normal length

   - Torpedo Bulkhead:
  2.00" / 51 mm 375.00 ft / 114.30 m 30.00 ft / 9.14 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 14.0" / 356 mm 6.00" / 152 mm  14.0" / 356 mm
 2nd: 4.00" / 102 mm 2.00" / 51 mm  4.00" / 102 mm

   - Armoured deck - multiple decks: 10.00" / 254 mm For and Aft decks

   - Conning towers: Forward 14.00" / 356 mm,  Aft 0.00" / 0 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 61,108 shp / 45,587 Kw = 23.70 kts
 Range 7,500nm at 18.00 kts
 Bunker at max displacement = 10,147 tons

Complement:
 1,303 - 1,694

Cost:
 £2.350 million / $9.399 million

Distribution of weights at normal displacement:
 Armament: 1,896 tons, 5.3 %
 Armour: 13,044 tons, 36.4 %
    - Belts: 2,856 tons, 8.0 %
    - Torpedo bulkhead: 833 tons, 2.3 %
    - Armament: 2,260 tons, 6.3 %
    - Armour Deck: 6,768 tons, 18.9 %
    - Conning Tower: 328 tons, 0.9 %
 Machinery: 2,778 tons, 7.7 %
 Hull, fittings & equipment: 11,168 tons, 31.1 %
 Fuel, ammunition & stores: 6,980 tons, 19.5 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   81,402 lbs / 36,923 Kg = 94.2 x 12.0 " / 305 mm shells or 15.0 torpedoes
 Stability (Unstable if below 1.00): 1.33
 Metacentric height 9.0 ft / 2.8 m
 Roll period: 14.8 seconds
 Steadiness - As gun platform (Average = 50 %): 88 %
   - Recoil effect (Restricted arc if above 1.00): 0.39
 Seaboat quality  (Average = 1.00): 1.77

Hull form characteristics:
 Hull has rise forward of midbreak,
   a normal bow and a cruiser stern
 Block coefficient (normal/deep): 0.612 / 0.624
 Length to Beam Ratio: 6.08 : 1
 'Natural speed' for length: 25.40 kts
 Power going to wave formation at top speed: 48 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 0.00 degrees
 Stern overhang: 0.00 ft / 0.00 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 33.00 %,  31.00 ft / 9.45 m,  27.00 ft / 8.23 m
    - Forward deck: 34.00 %,  27.00 ft / 8.23 m,  27.00 ft / 8.23 m
    - Aft deck: 18.00 %,  19.00 ft / 5.79 m,  19.00 ft / 5.79 m
    - Quarter deck: 15.00 %,  19.00 ft / 5.79 m,  19.00 ft / 5.79 m
    - Average freeboard:  24.89 ft / 7.59 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 61.8 %
  - Above water (accommodation/working, high = better): 179.1 %
 Waterplane Area: 50,568 Square feet or 4,698 Square metres
 Displacement factor (Displacement / loading): 130 %
 Structure weight / hull surface area: 170 lbs/sq ft or 829 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.94
  - Longitudinal: 1.80
  - 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
 Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Monday, July 09, 2007

The Ger/CB/1912 in Springsharp 3.0b2 Beta

The Ger/CB/1912 design seems like a natural for Springsharp 3.0b2 Beta, as it has inclined side armour. I do have a photo of one of the ships, as well:

This is a 32 knot ship with 6-15in/45 and 8-6in QF guns. The ship has a thick deck to go with the inclined side armour, so that despite the thin torpedo bulkhead, the ship is well-protected for a ship with thin side armour. This is the Springsharp report:
Ger/CB/1912, Germany Battlecruiser laid down 1912 (Engine 1937)

Displacement:
 35,294 t light; 36,855 t standard; 40,276 t normal; 43,013 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (824.00 ft / 820.00 ft) x 105.00 ft x (29.50 / 31.09 ft)
 (251.16 m / 249.94 m) x 32.00 m  x (8.99 / 9.48 m)

Armament:
      6 - 15.00" / 381 mm 45.0 cal guns - 1,700.00lbs / 771.11kg shells, 120 per gun
   Breech loading guns in turret on barbette mounts, 1912 Model
   2 x Triple mounts on centreline, forward deck forward
  1 raised mount - superfiring
      8 - 6.00" / 152 mm 50.0 cal guns - 114.00lbs / 51.71kg shells, 150 per gun
   Quick firing guns in deck and hoist mounts, 1912 Model
   8 x Single mounts on sides, forward deck aft
  2 raised mounts - superfiring
      Weight of broadside 11,112 lbs / 5,040 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 7.00" / 178 mm 400.00 ft / 121.92 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 75 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.00" / 25 mm 400.00 ft / 121.92 m 29.50 ft / 8.99 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 10.0" / 254 mm 6.00" / 152 mm  10.0" / 254 mm
 2nd: 4.00" / 102 mm 2.00" / 51 mm  4.00" / 102 mm

   - Armoured deck - multiple decks: 10.00" / 254 mm For and Aft decks

   - Conning towers: Forward 8.00" / 203 mm,  Aft 0.00" / 0 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Direct drive, 4 shafts, 186,573 shp / 139,184 Kw = 32.00 kts
 Range 8,000nm at 18.00 kts
 Bunker at max displacement = 6,158 tons

Complement:
 1,420 - 1,847

Cost:
 £3.007 million / $12.029 million

Distribution of weights at normal displacement:
 Armament: 1,964 tons, 4.9 %
 Armour: 12,611 tons, 31.3 %
    - Belts: 1,724 tons, 4.3 %
    - Torpedo bulkhead: 437 tons, 1.1 %
    - Armament: 1,935 tons, 4.8 %
    - Armour Deck: 8,314 tons, 20.6 %
    - Conning Tower: 203 tons, 0.5 %
 Machinery: 5,171 tons, 12.8 %
 Hull, fittings & equipment: 15,547 tons, 38.6 %
 Fuel, ammunition & stores: 4,983 tons, 12.4 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   71,592 lbs / 32,474 Kg = 42.4 x 15.0 " / 381 mm shells or 9.4 torpedoes
 Stability (Unstable if below 1.00): 1.21
 Metacentric height 7.6 ft / 2.3 m
 Roll period: 16.0 seconds
 Steadiness - As gun platform (Average = 50 %): 66 %
   - Recoil effect (Restricted arc if above 1.00): 0.50
 Seaboat quality  (Average = 1.00): 1.33

Hull form characteristics:
 Hull has rise forward of midbreak,
   a normal bow and a cruiser stern
 Block coefficient (normal/deep): 0.555 / 0.562
 Length to Beam Ratio: 7.81 : 1
 'Natural speed' for length: 28.64 kts
 Power going to wave formation at top speed: 53 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 0.00 degrees
 Stern overhang: 4.00 ft / 1.22 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 30.00 %,  36.00 ft / 10.97 m,  31.00 ft / 9.45 m
    - Forward deck: 30.00 %,  31.00 ft / 9.45 m,  30.00 ft / 9.14 m
    - Aft deck: 25.00 %,  22.00 ft / 6.71 m,  22.00 ft / 6.71 m
    - Quarter deck: 15.00 %,  22.00 ft / 6.71 m,  22.00 ft / 6.71 m
    - Average freeboard:  27.85 ft / 8.49 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 81.8 %
  - Above water (accommodation/working, high = better): 215.7 %
 Waterplane Area: 60,371 Square feet or 5,609 Square metres
 Displacement factor (Displacement / loading): 122 %
 Structure weight / hull surface area: 187 lbs/sq ft or 912 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.96
  - Longitudinal: 1.50
  - 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

Amazon Context Links