Escort Cruisers for Peru

[Jefgte]

8700T cruiser, Peru Eccort Cruiser laid down 1915

Displacement:
   8 700 t light; 9 309 t standard; 10 061 t normal; 10 663 t full load

Dimensions: Length overall / water x beam x draught
   538.06 ft / 538.06 ft x 67.26 ft x 17.85 ft (normal load)
   164.00 m / 164.00 m x 20.50 m  x 5.44 m

Armament:
      4 - 12.01" / 305 mm guns (2x2 guns), 865.70lbs / 392.68kg shells, 1915 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread
      2 - 12.01" / 305 mm guns (1x2 guns), 865.70lbs / 392.68kg shells, 1915 Model
     Breech loading guns in a turret (on a barbette)
     on centreline amidships
      8 - 4.72" / 120 mm guns in single mounts, 52.72lbs / 23.92kg shells, 1915 Model
     Breech loading guns in casemate mounts
     on side, evenly spread
      4 - 2.00" / 50.8 mm guns in single mounts, 4.00lbs / 1.81kg shells, 1915 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, 1915 Model
     Machine guns in deck mounts
     on side, evenly spread, all raised mounts
   Weight of broadside 5 632 lbs / 2 555 kg
   Shells per gun, main battery: 125
   4 - 21.0" / 533.4 mm submerged torpedo tubes

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   5.51" / 140 mm   341.21 ft / 104.00 m   9.19 ft / 2.80 m
   Ends:   1.57" / 40 mm   164.04 ft / 50.00 m   8.01 ft / 2.44 m
     32.81 ft / 10.00 m Unarmoured ends
     Main Belt covers 98 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   5.51" / 140 mm   1.57" / 40 mm      3.94" / 100 mm
   2nd:   5.51" / 140 mm   1.57" / 40 mm      3.94" / 100 mm
   3rd:   0.79" / 20 mm         -               -
   4th:   0.50" / 13 mm         -               -

   - Armour deck: 1.18" / 30 mm, Conning tower: 4.72" / 120 mm

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 30 000 shp / 22 380 Kw = 24.06 kts
   Range 7 000nm at 12.00 kts
   Bunker at max displacement = 1 354 tons

Complement:
   501 - 652

Cost:
   £1.535 million / $6.138 million

Distribution of weights at normal displacement:
   Armament: 704 tons, 7.0 %
   Armour: 1 821 tons, 18.1 %
      - Belts: 816 tons, 8.1 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 409 tons, 4.1 %
      - Armour Deck: 549 tons, 5.5 %
      - Conning Tower: 47 tons, 0.5 %
   Machinery: 1 136 tons, 11.3 %
   Hull, fittings & equipment: 4 878 tons, 48.5 %
   Fuel, ammunition & stores: 1 361 tons, 13.5 %
   Miscellaneous weights: 160 tons, 1.6 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     11 673 lbs / 5 295 Kg = 13.5 x 12.0 " / 305 mm shells or 1.7 torpedoes
   Stability (Unstable if below 1.00): 1.15
   Metacentric height 3.6 ft / 1.1 m
   Roll period: 14.9 seconds
   Steadiness   - As gun platform (Average = 50 %): 72 %
         - Recoil effect (Restricted arc if above 1.00): 0.81
   Seaboat quality  (Average = 1.00): 1.24

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0.545
   Length to Beam Ratio: 8.00 : 1
   'Natural speed' for length: 23.20 kts
   Power going to wave formation at top speed: 47 %
   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:      22.31 ft / 6.80 m
      - Forecastle (19 %):   18.04 ft / 5.50 m
      - Mid (40 %):      14.76 ft / 4.50 m
      - Quarterdeck (18 %):   14.76 ft / 4.50 m
      - Stern:      14.76 ft / 4.50 m
      - Average freeboard:   16.06 ft / 4.89 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 96.3 %
      - Above water (accommodation/working, high = better): 146.3 %
   Waterplane Area: 25 137 Square feet or 2 335 Square metres
   Displacement factor (Displacement / loading): 102 %
   Structure weight / hull surface area: 139 lbs/sq ft or 680 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.96
      - Longitudinal: 1.34
      - 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
   Good seaboat, rides out heavy weather easily

[Borys]

WOW!

[The Rock Doctor]

It sounds impressive, but is the hull wide enough, and deep enough, to support twin 12" turrets and their barbettes?

[Guinness]

I think it is. If we can expect a barbette diameter of about 26.5 to 27 feet (sorry metric folks) plus armor, then I think it'll fit ok on a beam of 67 feet. It's got a sufficiently high block coefficient that the hull shouldn't be too narrow alongside the fore and aft barbettes. I'm guessing there would be about 16.5  to 17 feet from the side of the barbettes fore and aft to the inside of the armor belt. It's narrow, but you can do it. They certainly aren't as close to the side as dreadnaught's wing turrets :).

Certainly there'd be no room for a tds though, so it's good there isn't one.

[Borys]

Swedish Coastal Battleships were smaller than she is. Fact is they had only 2x2x11".
Borys

[Jefgte]

(Note the Panzerschiff was 20.7m width for T3x280 in 1928)

But I increase beam & draught & decrease lenght

8600T cruiser, Peru Escort Cruiser laid down 1915

Displacement:
   8 600 t light; 9 207 t standard; 9 941 t normal; 10 528 t full load

Dimensions: Length overall / water x beam x draught
   505.25 ft / 505.25 ft x 68.90 ft x 19.41 ft (normal load)
   154.00 m / 154.00 m x 21.00 m  x 5.92 m

Armament:
      4 - 12.01" / 305 mm guns (2x2 guns), 865.70lbs / 392.67kg shells, 1915 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread
      2 - 12.01" / 305 mm guns (1x2 guns), 865.70lbs / 392.67kg shells, 1915 Model
     Breech loading guns in a turret (on a barbette)
     on centreline amidships
      8 - 4.72" / 120 mm guns in single mounts, 52.72lbs / 23.91kg shells, 1915 Model
     Breech loading guns in casemate mounts
     on side, evenly spread
      4 - 2.00" / 50.8 mm guns in single mounts, 4.00lbs / 1.81kg shells, 1915 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, 1915 Model
     Machine guns in deck mounts
     on side, evenly spread, all raised mounts
   Weight of broadside 5 632 lbs / 2 555 kg
   Shells per gun, main battery: 125
   4 - 21.0" / 533.4 mm submerged torpedo tubes

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   5.51" / 140 mm   321.52 ft / 98.00 m   10.17 ft / 3.10 m
   Ends:   1.57" / 40 mm   164.04 ft / 50.00 m   9.45 ft / 2.88 m
     19.69 ft / 6.00 m Unarmoured ends
     Main Belt covers 98 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   5.51" / 140 mm   1.57" / 40 mm      3.94" / 100 mm
   2nd:   5.51" / 140 mm   1.57" / 40 mm      3.94" / 100 mm
   3rd:   0.79" / 20 mm         -               -
   4th:   0.50" / 13 mm         -               -

   - Armour deck: 1.18" / 30 mm, Conning tower: 4.72" / 120 mm

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 29 986 shp / 22 370 Kw = 24.03 kts
   Range 7 000nm at 12.00 kts
   Bunker at max displacement = 1 322 tons

Complement:
   497 - 647

Cost:
   £1.529 million / $6.117 million

Distribution of weights at normal displacement:
   Armament: 704 tons, 7.1 %
   Armour: 1 841 tons, 18.5 %
      - Belts: 867 tons, 8.7 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 414 tons, 4.2 %
      - Armour Deck: 514 tons, 5.2 %
      - Conning Tower: 47 tons, 0.5 %
   Machinery: 1 136 tons, 11.4 %
   Hull, fittings & equipment: 4 759 tons, 47.9 %
   Fuel, ammunition & stores: 1 341 tons, 13.5 %
   Miscellaneous weights: 160 tons, 1.6 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     11 135 lbs / 5 051 Kg = 12.9 x 12.0 " / 305 mm shells or 1.7 torpedoes
   Stability (Unstable if below 1.00): 1.13
   Metacentric height 3.6 ft / 1.1 m
   Roll period: 15.2 seconds
   Steadiness   - As gun platform (Average = 50 %): 72 %
         - Recoil effect (Restricted arc if above 1.00): 0.79
   Seaboat quality  (Average = 1.00): 1.24

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0.515
   Length to Beam Ratio: 7.33 : 1
   'Natural speed' for length: 22.48 kts
   Power going to wave formation at top speed: 49 %
   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:      22.31 ft / 6.80 m
      - Forecastle (19 %):   18.37 ft / 5.60 m
      - Mid (40 %):      15.09 ft / 4.60 m
      - Quarterdeck (18 %):   15.09 ft / 4.60 m
      - Stern:      15.09 ft / 4.60 m
      - Average freeboard:   16.36 ft / 4.99 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 97.6 %
      - Above water (accommodation/working, high = better): 140.9 %
   Waterplane Area: 23 515 Square feet or 2 185 Square metres
   Displacement factor (Displacement / loading): 100 %
   Structure weight / hull surface area: 143 lbs/sq ft or 697 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.94
      - Longitudinal: 1.65
      - 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
   Good seaboat, rides out heavy weather easily