Amazon Ad

Monday, July 02, 2007

My concept for a fast French armoured cruiser

I have had this concept for a fast armoured cruiser with two turrets forward. I usually cast it as a French ship. This version has 8-9.4in/55 BLR, 12-5.5in/55, and 8-3.4in AA guns. With armour basis is 6in with a 3in deck. This is the Springsharp report:
F/CA/1917, France Armoured Cruiser laid down 1917 (Engine 1927)

Displacement:
 15,142 t light; 15,884 t standard; 16,962 t normal; 17,825 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (703.59 ft / 694.00 ft) x 74.00 ft x (20.00 / 20.82 ft)
 (214.45 m / 211.53 m) x 22.56 m  x (6.10 / 6.35 m)

Armament:
      8 - 9.40" / 239 mm 55.0 cal guns - 449.00lbs / 203.66kg shells, 150 per gun
   Breech loading guns in turret on barbette mounts, 1917 Model
   2 x Quad mounts on centreline, forward deck forward
  1 raised mount - superfiring
      12 - 5.50" / 140 mm 55.0 cal guns - 90.00lbs / 40.82kg shells, 150 per gun
   Quick firing guns in turret on barbette mounts, 1917 Model
   4 x Triple mounts on sides, aft deck forward
      8 - 3.40" / 86.4 mm 50.0 cal guns - 20.80lbs / 9.44kg shells, 150 per gun
   Anti-air guns in deck and hoist mounts, 1917 Model
   4 x Twin mounts on sides, aft deck aft
  4 raised mounts
      Weight of broadside 4,838 lbs / 2,195 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 6.00" / 152 mm 450.00 ft / 137.16 m 12.00 ft / 3.66 m
 Ends: Unarmoured
   Main Belt covers 100 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  1.00" / 25 mm 450.00 ft / 137.16 m 19.00 ft / 5.79 m

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

   - Box over magazines: 3.00" / 76 mm

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

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 130,832 shp / 97,601 Kw = 33.00 kts
 Range 5,600nm at 15.00 kts
 Bunker at max displacement = 1,940 tons

Complement:
 743 - 966

Cost:
 £3.021 million / $12.082 million

Distribution of weights at normal displacement:
 Armament: 1,320 tons, 7.8 %
 Armour: 2,527 tons, 14.9 %
    - Belts: 1,345 tons, 7.9 %
    - Torpedo bulkhead: 316 tons, 1.9 %
    - Armament: 657 tons, 3.9 %
    - Armour Deck: 123 tons, 0.7 %
    - Conning Tower: 85 tons, 0.5 %
 Machinery: 4,130 tons, 24.3 %
 Hull, fittings & equipment: 7,165 tons, 42.2 %
 Fuel, ammunition & stores: 1,820 tons, 10.7 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   18,873 lbs / 8,561 Kg = 45.4 x 9.4 " / 239 mm shells or 2.4 torpedoes
 Stability (Unstable if below 1.00): 1.13
 Metacentric height 4.0 ft / 1.2 m
 Roll period: 15.5 seconds
 Steadiness - As gun platform (Average = 50 %): 53 %
   - Recoil effect (Restricted arc if above 1.00): 0.71
 Seaboat quality  (Average = 1.00): 1.06

Hull form characteristics:
 Hull has rise forward of midbreak,
   an extended bulbous bow and a cruiser stern
 Block coefficient (normal/deep): 0.578 / 0.583
 Length to Beam Ratio: 9.38 : 1
 'Natural speed' for length: 26.34 kts
 Power going to wave formation at top speed: 56 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 12.00 degrees
 Stern overhang: 3.00 ft / 0.91 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 27.00 %,  31.00 ft / 9.45 m,  27.00 ft / 8.23 m
    - Forward deck: 36.00 %,  27.00 ft / 8.23 m,  27.00 ft / 8.23 m
    - Aft deck: 21.00 %,  19.00 ft / 5.79 m,  19.00 ft / 5.79 m
    - Quarter deck: 16.00 %,  19.00 ft / 5.79 m,  19.00 ft / 5.79 m
    - Average freeboard:  24.47 ft / 7.46 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 149.1 %
  - Above water (accommodation/working, high = better): 226.9 %
 Waterplane Area: 36,795 Square feet or 3,418 Square metres
 Displacement factor (Displacement / loading): 106 %
 Structure weight / hull surface area: 141 lbs/sq ft or 690 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.96
  - Longitudinal: 1.34
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

No comments:

Amazon Context Links