Small battleship for Peru

[Borys]

Ahoj!
I found a small battleship design for Peru on my HDD.
Slow, but nicely armed and quite well armoured. Well, at 18K you can't have everything :)

Locas y Despidas, Peru Acorazado laid down 1912

Displacement:
   17 947 t light; 18 906 t standard; 20 030 t normal; 20 930 t full load

Dimensions: Length overall / water x beam x draught
   540,00 ft / 540,00 ft x 90,00 ft x 25,00 ft (normal load)
   164,59 m / 164,59 m x 27,43 m  x 7,62 m

Armament:
      8 - 13,50" / 343 mm guns (4x2 guns), 1 250,00lbs / 566,99kg shells, 1912 Model
     Breech loading guns in turrets (on barbettes)
     on centreline, evenly spread
     Aft Main mounts separated by engine room
      10 - 6,00" / 152 mm guns in single mounts, 100,00lbs / 45,36kg shells, 1912 Model
     Breech loading guns in casemate mounts
     on side, all amidships
   Weight of broadside 11 000 lbs / 4 990 kg
   Shells per gun, main battery: 90

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   11,0" / 279 mm   350,00 ft / 106,68 m   16,00 ft / 4,88 m
   Ends:   4,00" / 102 mm   190,00 ft / 57,91 m   12,00 ft / 3,66 m
   Upper:   6,00" / 152 mm   350,00 ft / 106,68 m   8,00 ft / 2,44 m
     Main Belt covers 100% of normal length

   - Torpedo Bulkhead:
      2,00" / 51 mm   350,00 ft / 106,68 m   40,00 ft / 12,19 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   13,0" / 330 mm   6,00" / 152 mm      8,00" / 203 mm
   2nd:   4,00" / 102 mm         -         1,00" / 25 mm

   - Armour deck: 2,00" / 51 mm, Conning tower: 13,00" / 330 mm

Machinery:
   Coal fired boilers, steam turbines,
   Direct drive, 4 shafts, 15 784 shp / 11 775 Kw = 18,00 kts
   Range 6 500nm at 10,00 kts
   Bunker at max displacement = 2 024 tons (100% coal)

Complement:
   841 - 1 094

Cost:
   £1,872 million / $7,487 million

Distribution of weights at normal displacement:
   Armament: 1 365 tons, 6,8%
   Armour: 7 938 tons, 39,6%
      - Belts: 3 790 tons, 18,9%
      - Torpedo bulkhead: 1 036 tons, 5,2%
      - Armament: 1 619 tons, 8,1%
      - Armour Deck: 1 287 tons, 6,4%
      - Conning Tower: 207 tons, 1,0%
   Machinery: 692 tons, 3,5%
   Hull, fittings & equipment: 7 551 tons, 37,7%
   Fuel, ammunition & stores: 2 084 tons, 10,4%
   Miscellaneous weights: 400 tons, 2,0%

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     30 155 lbs / 13 678 Kg = 24,5 x 13,5 " / 343 mm shells or 6,2 torpedoes
   Stability (Unstable if below 1.00): 1,16
   Metacentric height 5,7 ft / 1,7 m
   Roll period: 15,9 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0,54
   Seaboat quality  (Average = 1.00): 1,41

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0,577
   Length to Beam Ratio: 6,00 : 1
   'Natural speed' for length: 23,24 kts
   Power going to wave formation at top speed: 37 %
   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 (% = measuring location as a percentage of overall length):
      - Stem:      25,59 ft / 7,80 m
      - Forecastle (20%):   16,29 ft / 4,97 m
      - Mid (50%):      16,29 ft / 4,97 m
      - Quarterdeck (15%):   16,29 ft / 4,97 m
      - Stern:      16,29 ft / 4,97 m
      - Average freeboard:   17,03 ft / 5,19 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 83,1%
      - Above water (accommodation/working, high = better): 128,3%
   Waterplane Area: 34 788 Square feet or 3 232 Square metres
   Displacement factor (Displacement / loading): 97%
   Structure weight / hull surface area: 162 lbs/sq ft or 793 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,95
      - Longitudinal: 1,51
      - Overall: 1,00
   Hull space for machinery, storage, compartmentation is excellent
   Room for accommodation and workspaces is excellent
   Ship has slow, easy roll, a good, steady gun platform
   Good seaboat, rides out heavy weather easily

[Jefgte]

This design is about brother with Atahualpa BB actualy in Callao Shipyards.

I note some differences:
- Heavier secondary armament
- Belt & deck thinner but heavier global protection
- LowerSpeed
- Better torpedo protection
- Higher survivability
...

How design this good BB?

Ohhhh Yess, probably a pale faced Gringo who have visited Callao Shipyards  :D :D :D

-------------------------------------------------------------

For comparison
Atahualpa - Laid down in 1911 - in service 1914

18000T-4T2x340, Peru BB laid down 1911

Displacement:
   18 000 t light; 19 029 t standard; 20 383 t normal; 21 467 t full load

Dimensions: Length overall / water x beam x draught
   551.18 ft / 551.18 ft x 85.30 ft x 24.63 ft (normal load)
   168.00 m / 168.00 m x 26.00 m  x 7.51 m

Armament:
      4 - 13.39" / 340 mm guns (2x2 guns), 1 200.00lbs / 544.31kg shells, 1911 Model
     Breech loading guns in turrets (on barbettes)
     on centreline, evenly spread
      4 - 13.39" / 340 mm guns (2x2 guns), 1 200.00lbs / 544.31kg shells, 1911 Model
     Breech loading guns in turrets (on barbettes)
     on side, all amidships
      12 - 4.72" / 120 mm guns in single mounts, 52.72lbs / 23.91kg shells, 1911 Model
     Breech loading guns in casemate mounts
     on side, evenly spread
      16 - 3.54" / 90.0 mm guns in single mounts, 22.24lbs / 10.09kg shells, 1911 Model
     Quick firing guns in deck mounts
     on side, evenly spread, all raised mounts
      4 - 0.50" / 12.7 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1911 Model
     Machine guns in deck mounts
     on side, evenly spread, all raised mounts
   Weight of broadside 10 589 lbs / 4 803 kg
   Shells per gun, main battery: 100
   4 - 21.0" / 533 mm submerged torpedo tubes

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   13.4" / 340 mm   341.21 ft / 104.00 m   10.17 ft / 3.10 m
   Ends:   4.02" / 102 mm   190.29 ft / 58.00 m   10.17 ft / 3.10 m
     19.69 ft / 6.00 m Unarmoured ends
   Upper:   4.02" / 102 mm   341.21 ft / 104.00 m   8.01 ft / 2.44 m
     Main Belt covers 95 % of normal length

   - Torpedo Bulkhead:
      1.57" / 40 mm   341.21 ft / 104.00 m   24.51 ft / 7.47 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   13.4" / 340 mm   4.02" / 102 mm      11.8" / 300 mm
   2nd:   13.4" / 340 mm   4.02" / 102 mm      11.8" / 300 mm
   3rd:   1.97" / 50 mm         -               -
   4th:   0.79" / 20 mm         -               -
   5th:   0.50" / 13 mm         -               -

   - Armour deck: 3.54" / 90 mm, Conning tower: 13.39" / 340 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 4 shafts, 29 000 shp / 21 634 Kw = 21.13 kts
   Range 7 000nm at 12.00 kts
   Bunker at max displacement = 2 438 tons

Complement:
   852 - 1 108

Cost:
   £1.906 million / $7.624 million

Distribution of weights at normal displacement:
   Armament: 1 323 tons, 6.5 %
   Armour: 7 463 tons, 36.6 %
      - Belts: 2 829 tons, 13.9 %
      - Torpedo bulkhead: 487 tons, 2.4 %
      - Armament: 1 644 tons, 8.1 %
      - Armour Deck: 2 288 tons, 11.2 %
      - Conning Tower: 215 tons, 1.1 %
   Machinery: 1 177 tons, 5.8 %
   Hull, fittings & equipment: 7 637 tons, 37.5 %
   Fuel, ammunition & stores: 2 384 tons, 11.7 %
   Miscellaneous weights: 400 tons, 2.0 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     24 963 lbs / 11 323 Kg = 20.8 x 13.4 " / 340 mm shells or 4.5 torpedoes
   Stability (Unstable if below 1.00): 1.10
   Metacentric height 4.8 ft / 1.5 m
   Roll period: 16.4 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.57
   Seaboat quality  (Average = 1.00): 1.21

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0.616
   Length to Beam Ratio: 6.46 : 1
   'Natural speed' for length: 23.48 kts
   Power going to wave formation at top speed: 45 %
   Trim (Max stability = 0, Max steadiness = 100): 58
   Bow angle (Positive = bow angles forward): 0.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      20.67 ft / 6.30 m
      - Forecastle (18 %):   16.40 ft / 5.00 m
      - Mid (30 %):      14.11 ft / 4.30 m
      - Quarterdeck (18 %):   14.11 ft / 4.30 m
      - Stern:      14.11 ft / 4.30 m
      - Average freeboard:   14.97 ft / 4.56 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 94.9 %
      - Above water (accommodation/working, high = better): 111.8 %
   Waterplane Area: 34 904 Square feet or 3 243 Square metres
   Displacement factor (Displacement / loading): 98 %
   Structure weight / hull surface area: 165 lbs/sq ft or 807 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.97
      - Longitudinal: 1.26
      - Overall: 1.00
   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
   Good seaboat, rides out heavy weather easily

[Borys]

Your design points out the advantages of oil firing.
That gives you those 3 knots and the other little things.
Borys