Amazon Ad

Monday, July 25, 2005

My Ger/CB/1915 design study doesn't work without changes

To make my Hood-looking German battlecruiser design study for a Ger/CB/1915 class, I had to increase the displacement and draft to achieve adequate structural strenght. I also had to decrease freeboard, oddly enough, to reduce weight. I also was not able to achieve the 16,650 tons of protection of that I had wanted. The armor basis is 12in, which is adequate, but it suffers from having been originally a 9in armor basis that had a thicker belt added. Instead of four twin turrets, this design has three triple turrets. Otherwise, it resembles the Hood. This is the Springsharp report:
Ger/CB/1915 design study, Enter country Enter ship type laid down 1915 (Engine 1927)

Displacement:
 42,889 t light; 44,780 t standard; 46,800 t normal; 48,416 t full load

Dimensions: Length overall / water x beam x draught
 851.12 ft / 850.00 ft x 110.00 ft x 32.00 ft (normal load)
 259.42 m / 259.08 m x 33.53 m  x 9.75 m

Armament:
      9 - 16.50" / 419 mm guns (3x3 guns), 2,246.06lbs / 1,018.80kg shells, 1915 Model
   Breech loading guns in turrets (on barbettes)
   on centreline ends, majority forward
      10 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1915 Model
   Quick firing guns in deck mounts with hoists
   on side, all amidships, 2 raised mounts - superfiring
 Weight of broadside 21,295 lbs / 9,659 kg
 Shells per gun, main battery: 80

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 12.0" / 305 mm 480.00 ft / 146.30 m 9.00 ft / 2.74 m
 Ends: Unarmoured
 Upper: 12.0" / 305 mm 480.00 ft / 146.30 m 8.00 ft / 2.44 m
   Main Belt covers 87 % of normal length
   Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
  2.00" / 51 mm 480.00 ft / 146.30 m 28.00 ft / 8.53 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: 2.00" / 51 mm       -         -

   - Armour deck: 4.00" / 102 mm, Conning tower: 10.00" / 254 mm

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 4 shafts, 227,396 shp / 169,638 Kw = 33.00 kts
 Range 5,600nm at 15.00 kts
 Bunker at max displacement = 3,636 tons

Complement:
 1,590 - 2,068

Cost:
 £6.897 million / $27.590 million

Distribution of weights at normal displacement:
 Armament: 2,662 tons, 5.7 %
 Armour: 13,108 tons, 28.0 %
    - Belts: 4,306 tons, 9.2 %
    - Torpedo bulkhead: 995 tons, 2.1 %
    - Armament: 2,710 tons, 5.8 %
    - Armour Deck: 4,817 tons, 10.3 %
    - Conning Tower: 280 tons, 0.6 %
 Machinery: 7,178 tons, 15.3 %
 Hull, fittings & equipment: 19,942 tons, 42.6 %
 Fuel, ammunition & stores: 3,911 tons, 8.4 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   56,408 lbs / 25,586 Kg = 25.1 x 16.5 " / 419 mm shells or 6.9 torpedoes
 Stability (Unstable if below 1.00): 1.17
 Metacentric height 7.7 ft / 2.4 m
 Roll period: 16.6 seconds
 Steadiness - As gun platform (Average = 50 %): 56 %
   - Recoil effect (Restricted arc if above 1.00): 0.66
 Seaboat quality  (Average = 1.00): 1.11

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.547
 Length to Beam Ratio: 7.73 : 1
 'Natural speed' for length: 29.15 kts
 Power going to wave formation at top speed: 54 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 2.00 degrees
 Stern overhang: -2.00 ft / -0.61 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  32.00 ft / 9.75 m
    - Forecastle (20 %): 29.00 ft / 8.84 m
    - Mid (64 %):  29.00 ft / 8.84 m (21.00 ft / 6.40 m aft of break)
    - Quarterdeck (15 %): 21.00 ft / 6.40 m
    - Stern:  21.00 ft / 6.40 m
    - Average freeboard: 26.36 ft / 8.03 m
 Ship tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 112.4 %
  - Above water (accommodation/working, high = better): 206.0 %
 Waterplane Area: 65,098 Square feet or 6,048 Square metres
 Displacement factor (Displacement / loading): 96 %
 Structure weight / hull surface area: 215 lbs/sq ft or 1,052 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.97
  - Longitudinal: 1.36
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent

1 comment:

startonline said...

Hi :)

You have a great blog! Keep up the great work, and I'll be sure to visit regularly.

I have a social work degree online related site, check it out if you get some time!

Look forward to reading more of your insightful post!

Amazon Context Links