Amazon Ad

Saturday, May 14, 2005

A fast, lightly protected British battlecruiser design, circa 1919-1920

One concept that was discussed after the end of the war, about 1919 0r 1920, was a ship to match the early design for the American battlecruisers. This would have been 850ft x 104ft, with 8-15in and 16-6in guns. The speed would have been 33 knots, so the side armor was to be on the order of 5in. I just attempted a Springsharp design for such a ship. The main problem with what is needed is Springsharp is the size (too big):
GB/CB/1919 Fast, Great Britain Battlecruiser laid down 1919 (Engine 1927)

Displacement:
 39,824 t light; 41,602 t standard; 44,453 t normal; 46,733 t full load

Dimensions: Length overall / water x beam x draught
 851.15 ft / 850.00 ft x 104.00 ft x 32.00 ft (normal load)
 259.43 m / 259.08 m x 31.70 m  x 9.75 m

Armament:
      8 - 15.00" / 381 mm guns (4x2 guns), 1,687.50lbs / 765.44kg shells, 1919 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, evenly spread, all raised mounts - superfiring
      16 - 6.00" / 152 mm guns (8x2 guns), 108.00lbs / 48.99kg shells, 1919 Model
   Quick firing guns in turrets (on barbettes)
   on side, all amidships, all raised mounts - superfiring
      6 - 4.70" / 119 mm guns in single mounts, 51.91lbs / 23.55kg shells, 1919 Model
   Anti-aircraft guns in deck mounts with hoists
   on side, evenly spread, all raised mounts
      32 - 1.57" / 40.0 mm guns (8x4 guns), 1.95lbs / 0.89kg shells, 1919 Model
   Breech loading guns in deck mounts 
   on side, evenly spread, all raised mounts
 Weight of broadside 15,602 lbs / 7,077 kg
 Shells per gun, main battery: 100

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 5.00" / 127 mm 590.00 ft / 179.83 m 18.00 ft / 5.49 m
 Ends: 4.00" / 102 mm 240.00 ft / 73.15 m 18.00 ft / 5.49 m
   20.00 ft / 6.10 m Unarmoured ends
   Main Belt covers 107 % of normal length

   - Torpedo Bulkhead:
  2.00" / 51 mm 590.00 ft / 179.83 m 27.00 ft / 8.23 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 9.00" / 229 mm 5.00" / 127 mm  8.00" / 203 mm
 2nd: 2.00" / 51 mm 2.00" / 51 mm  2.00" / 51 mm

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

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 218,578 shp / 163,059 Kw = 33.00 kts
 Range 8,500nm at 15.00 kts
 Bunker at max displacement = 5,132 tons

Complement:
 1,529 - 1,989

Cost:
 £8.723 million / $34.891 million

Distribution of weights at normal displacement:
 Armament: 1,950 tons, 4.4 %
 Armour: 11,761 tons, 26.5 %
    - Belts: 2,870 tons, 6.5 %
    - Torpedo bulkhead: 1,179 tons, 2.7 %
    - Armament: 2,903 tons, 6.5 %
    - Armour Deck: 4,565 tons, 10.3 %
    - Conning Tower: 243 tons, 0.5 %
 Machinery: 6,900 tons, 15.5 %
 Hull, fittings & equipment: 19,213 tons, 43.2 %
 Fuel, ammunition & stores: 4,629 tons, 10.4 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   58,092 lbs / 26,350 Kg = 34.4 x 15.0 " / 381 mm shells or 7.5 torpedoes
 Stability (Unstable if below 1.00): 1.05
 Metacentric height 5.8 ft / 1.8 m
 Roll period: 18.1 seconds
 Steadiness - As gun platform (Average = 50 %): 57 %
   - Recoil effect (Restricted arc if above 1.00): 0.92
 Seaboat quality  (Average = 1.00): 1.13

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.550
 Length to Beam Ratio: 8.17 : 1
 'Natural speed' for length: 29.15 kts
 Power going to wave formation at top speed: 53 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 2.00 degrees
 Stern overhang: -2.00 ft / -0.61 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  33.00 ft / 10.06 m
    - Forecastle (20 %): 31.00 ft / 9.45 m
    - Mid (67 %):  31.00 ft / 9.45 m (23.00 ft / 7.01 m aft of break)
    - Quarterdeck (15 %): 23.00 ft / 7.01 m
    - Stern:  23.00 ft / 7.01 m
    - Average freeboard: 28.52 ft / 8.69 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 103.6 %
  - Above water (accommodation/working, high = better): 221.2 %
 Waterplane Area: 61,694 Square feet or 5,732 Square metres
 Displacement factor (Displacement / loading): 108 %
 Structure weight / hull surface area: 210 lbs/sq ft or 1,025 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.96
  - Longitudinal: 1.33
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is adequate
 Room for accommodation and workspaces is excellent

No comments:

Amazon Context Links