Ottoman Light Cruiser Design Contest

[Kaiser Kirk]

I could give that a try later, but I don't think the results will be lovely.
The larger guns and the larger engine and more fuel can probably be compensated for by lowering the freeboard and miscellaneous weight.   However, that does mean the seakeeping drops, and I expect the internal volume will suffer and survivability will drop. The belt will need to be longer, and may have to become thinner.  I might be able to adjust the hull adequately, and dropping to 8x165 might help.
I dunno.

[miketr]

I went with 150mm as the Turks already have that as their cruiser weapon.  I can see some advantges for a 165mm gun design to out range / out gun Iberian and Hapsburg light cruisers.

Here is a new set of design requirements.

165mm main guns in four twin mounts.
75mm to 100mm main belt (matching protection for guns)
25mm to 40mm deck
30 knots to 32 knots, oil fired 1916 engines and 7,500 miles @ 12 knots
300 misc tons for FC, Mines and Radio
7,250 Light Displacement and to fit on a type 2 slipway.

[Kaiser Kirk]

Could we have this version of the Bavarian to compare? ;D 

Going with 8x165, 31kts, 7500nm @14kts on the same hullform, it's necessary to go with a low flush deck, 75mm belt and 25mm deck and seakeeping drops to 0.89 while flotation drops to 6691tons, and hull space become cramped.   Not something I'd submit.  A new design would be needed, pushing the L:B up, and BC and draft down.

The revamp is cramped internally and down to 7,696 flotation with a thinner belt and deck.  Further, the designers are concerned that the rotating weight of a twin 165mm with 75mm armor is high and may be more suited for more reinforced deck spot or a barbette, and the heavier the mount the slower the training rates. The vessel would look something like this :

Bazibazouk II, Ottoman Cruiser laid down 1917 (Engine 1916)

Displacement:
   7,250 t light; 7,573 t standard; 8,532 t normal; 9,300 t full load

Dimensions: Length overall / water x beam x draught
   546.78 ft / 538.06 ft x 53.81 ft x 19.69 ft (normal load)
   166.66 m / 164.00 m x 16.40 m  x 6.00 m

Armament:
      8 - 6.50" / 165 mm guns (4x2 guns), 143.30lbs / 65.00kg shells, 1910 Model
     Breech loading guns in deck mounts with hoists
     on centreline ends, evenly spread, 2 raised mounts - superfiring
      4 - 2.95" / 75.0 mm guns in single mounts, 12.87lbs / 5.84kg shells, 1910 Model
     Quick firing guns in deck mounts
     on side ends, evenly spread
   Weight of broadside 1,198 lbs / 543 kg
   Shells per gun, main battery: 225
   12 - 18.0" / 457.2 mm above water torpedoes

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   2.95" / 75 mm   426.51 ft / 130.00 m   11.48 ft / 3.50 m
   Ends:   Unarmoured
     Main Belt covers 122 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   2.95" / 75 mm   0.79" / 20 mm      2.95" / 75 mm
   2nd:   0.79" / 20 mm   0.20" / 5 mm            -

   - Armour deck: 0.98" / 25 mm, Conning tower: 2.95" / 75 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 70,789 shp / 52,809 Kw = 31.00 kts
   Range 7,500nm at 14.00 kts
   Bunker at max displacement = 1,727 tons

Complement:
   443 - 577

Cost:
   £1.352 million / $5.408 million

Distribution of weights at normal displacement:
   Armament: 143 tons, 1.7 %
   Armour: 1,035 tons, 12.1 %
      - Belts: 585 tons, 6.9 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 64 tons, 0.8 %
      - Armour Deck: 359 tons, 4.2 %
      - Conning Tower: 27 tons, 0.3 %
   Machinery: 2,637 tons, 30.9 %
   Hull, fittings & equipment: 3,119 tons, 36.6 %
   Fuel, ammunition & stores: 1,282 tons, 15.0 %
   Miscellaneous weights: 316 tons, 3.7 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     7,696 lbs / 3,491 Kg = 56.1 x 6.5 " / 165 mm shells or 1.1 torpedoes
   Stability (Unstable if below 1.00): 1.17
   Metacentric height 2.6 ft / 0.8 m
   Roll period: 13.9 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.53
   Seaboat quality  (Average = 1.00): 1.20

Hull form characteristics:
   Hull has low quarterdeck
   Block coefficient: 0.524
   Length to Beam Ratio: 10.00 : 1
   'Natural speed' for length: 23.20 kts
   Power going to wave formation at top speed: 58 %
   Trim (Max stability = 0, Max steadiness = 100): 58
   Bow angle (Positive = bow angles forward): 12.00 degrees
   Stern overhang: 3.28 ft / 1.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      25.59 ft / 7.80 m
      - Forecastle (20 %):   20.31 ft / 6.19 m
      - Mid (50 %):      20.31 ft / 6.19 m
      - Quarterdeck (15 %):   12.30 ft / 3.75 m (20.31 ft / 6.19 m before break)
      - Stern:      12.30 ft / 3.75 m
      - Average freeboard:   19.53 ft / 5.95 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 118.1 %
      - Above water (accommodation/working, high = better): 136.1 %
   Waterplane Area: 19,720 Square feet or 1,832 Square metres
   Displacement factor (Displacement / loading): 110 %
   Structure weight / hull surface area: 92 lbs/sq ft or 450 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.94
      - Longitudinal: 1.68
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is excellent
   Ship has slow, easy roll, a good, steady gun platform
   Good seaboat, rides out heavy weather easily

Main battery is A, B, Q, Y, X
75mm are in P1, 5 & S  1, 5
Torpedoes are in P2, 4 &  S 2, 4


100 tons Fire control
25 tons long range wireless
120 tons mines
12 tons torpedoes
59 tons construction reserve
----
316

[Desertfox]

Quick and dirty, with bigger guns.


Aurora class, New Switzerland Cruiser laid down 1916

Displacement:
   7,299 t light; 7,667 t standard; 9,140 t normal; 10,318 t full load

Dimensions: Length overall / water x beam x draught
   550.00 ft / 550.00 ft x 55.00 ft x 22.50 ft (normal load)
   167.64 m / 167.64 m x 16.76 m  x 6.86 m

Armament:
      8 - 6.50" / 165 mm guns (4x2 guns), 137.06lbs / 62.17kg shells, 1916 Model
     Breech loading guns in deck mounts with hoists
     on centreline ends, evenly spread, 2 raised mounts - superfiring
      8 - 2.95" / 75.0 mm guns in single mounts, 12.87lbs / 5.84kg shells, 1916 Model
     Breech loading guns in deck mounts
     on side, evenly spread
      8 - 0.59" / 15.0 mm guns (4x2 guns), 0.10lbs / 0.05kg shells, 1916 Model
     Machine guns in deck mounts
     on side, evenly spread
   Weight of broadside 1,200 lbs / 544 kg
   Shells per gun, main battery: 270
   12 - 17.7" / 450 mm above water torpedoes

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   3.94" / 100 mm   400.26 ft / 122.00 m   9.00 ft / 2.74 m
   Ends:   Unarmoured
     Main Belt covers 112 % of normal length
     Main belt does not fully cover magazines and engineering spaces

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.18" / 30 mm   0.79" / 20 mm      0.79" / 20 mm

   - Armour deck: 1.18" / 30 mm, Conning tower: 3.94" / 100 mm

Machinery:
   Oil fired boilers, steam turbines,
   Electric motors, 4 shafts, 71,439 shp / 53,294 Kw = 31.00 kts
   Range 4,800nm at 20.00 kts
   Bunker at max displacement = 2,650 tons

Complement:
   466 - 607

Cost:
   £1.234 million / $4.936 million

Distribution of weights at normal displacement:
   Armament: 150 tons, 1.6 %
   Armour: 1,081 tons, 11.8 %
      - Belts: 579 tons, 6.3 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 36 tons, 0.4 %
      - Armour Deck: 429 tons, 4.7 %
      - Conning Tower: 37 tons, 0.4 %
   Machinery: 2,662 tons, 29.1 %
   Hull, fittings & equipment: 3,086 tons, 33.8 %
   Fuel, ammunition & stores: 1,841 tons, 20.1 %
   Miscellaneous weights: 320 tons, 3.5 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     8,122 lbs / 3,684 Kg = 59.3 x 6.5 " / 165 mm shells or 1.2 torpedoes
   Stability (Unstable if below 1.00): 1.19
   Metacentric height 2.8 ft / 0.9 m
   Roll period: 13.8 seconds
   Steadiness   - As gun platform (Average = 50 %): 69 %
         - Recoil effect (Restricted arc if above 1.00): 0.40
   Seaboat quality  (Average = 1.00): 1.12

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0.470
   Length to Beam Ratio: 10.00 : 1
   'Natural speed' for length: 23.45 kts
   Power going to wave formation at top speed: 55 %
   Trim (Max stability = 0, Max steadiness = 100): 62
   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:      27.00 ft / 8.23 m
      - Forecastle (20 %):   19.00 ft / 5.79 m
      - Mid (40 %):      19.00 ft / 5.79 m
      - Quarterdeck (15 %):   14.00 ft / 4.27 m
      - Stern:      14.00 ft / 4.27 m
      - Average freeboard:   17.77 ft / 5.41 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 112.1 %
      - Above water (accommodation/working, high = better): 111.6 %
   Waterplane Area: 19,624 Square feet or 1,823 Square metres
   Displacement factor (Displacement / loading): 115 %
   Structure weight / hull surface area: 93 lbs/sq ft or 454 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.95
      - Longitudinal: 1.46
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is adequate

[TexanCowboy]

I tried resimming mine, but I can't give you my design reworked at 7,250. If you want a 10 gunned ship, try raising the limit to 7,750.

[maddox]

I like her myself. But France won't use the design.

Topkapi, Ottoman Protected cruiser laid down 1917 (Engine 1916)

Displacement:
   7.243 t light; 7.552 t standard; 8.602 t normal; 9.442 t full load

Dimensions: Length overall / water x beam x draught
   557,74 ft / 554,46 ft x 49,21 ft x 19,36 ft (normal load)
   170,00 m / 169,00 m x 15,00 m  x 5,90 m

Armament:
     10 - 6,50" / 165 mm guns (5x2 guns), 137,06lbs / 62,17kg shells, 1917 Model
     Breech loading guns in deck mounts with hoists
     on centreline, evenly spread, 2 raised mounts
     4 - 0,98" / 25,0 mm guns in single mounts, 0,48lbs / 0,22kg shells, 1917 Model
     Machine guns in deck mounts
     on side, all amidships, all raised mounts - superfiring
   Weight of broadside 1.373 lbs / 623 kg
   Shells per gun, main battery: 180
   6 - 20,0" / 508 mm above water torpedoes

Armour:
  - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   4,00" / 102 mm   421,39 ft / 128,44 m   12,00 ft / 3,66 m
   Ends:   Unarmoured
     Main Belt covers 117% of normal length

  - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   2,00" / 51 mm   1,00" / 25 mm      3,00" / 76 mm
   2nd:   0,50" / 13 mm         -               -

  - Armour deck: 1,50" / 38 mm

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 4 shafts, 70.451 shp / 52.556 Kw = 31,00 kts
   Range 6.000nm at 16,00 kts
   Range 11.500nm at 12,00 kts
   Bunker at max displacement = 1.889 tons

Complement:
   446 - 580

Cost:
   £1,391 million / $5,564 million

Distribution of weights at normal displacement:
   Armament: 172 tons, 2,0%
   Armour: 1.425 tons, 16,6%
      - Belts: 818 tons, 9,5%
      - Torpedo bulkhead: 0 tons, 0,0%
      - Armament: 69 tons, 0,8%
      - Armour Deck: 538 tons, 6,3%
      - Conning Tower: 0 tons, 0,0%
   Machinery: 2.625 tons, 30,5%
   Hull, fittings & equipment: 2.896 tons, 33,7%
   Fuel, ammunition & stores: 1.359 tons, 15,8%
   Miscellaneous weights: 125 tons, 1,5%

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     7.095 lbs / 3.218 Kg = 51,8 x 6,5 " / 165 mm shells or 1,0 torpedoes
   Stability (Unstable if below 1.00): 1,13
   Metacentric height 2,2 ft / 0,7 m
   Roll period: 14,1 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0,69
   Seaboat quality  (Average = 1.00): 1,04

Hull form characteristics:
   Hull has low quarterdeck
   Block coefficient: 0,570
   Length to Beam Ratio: 11,27 : 1
   'Natural speed' for length: 23,55 kts
   Power going to wave formation at top speed: 57 %
   Trim (Max stability = 0, Max steadiness = 100): 67
   Bow angle (Positive = bow angles forward): 5,00 degrees
   Stern overhang: 0,98 ft / 0,30 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      26,25 ft / 8,00 m
      - Forecastle (15%):   19,19 ft / 5,85 m
      - Mid (55%):      16,40 ft / 5,00 m
      - Quarterdeck (9%):   9,84 ft / 3,00 m (16,40 ft / 5,00 m before break)
      - Stern:      9,84 ft / 3,00 m
      - Average freeboard:   17,21 ft / 5,25 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 116,3%
      - Above water (accommodation/working, high = better): 122,5%
   Waterplane Area: 19.404 Square feet or 1.803 Square metres
   Displacement factor (Displacement / loading): 105%
   Structure weight / hull surface area: 89 lbs/sq ft or 433 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,98
      - Longitudinal: 1,21
      - Overall: 1,00
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is excellent
   Ship has slow, easy roll, a good, steady gun platform


Misc weight

12 tons for the torpedo's  (6 in the tubes, 1 spare each tube)
100 tons available  for FC
13 tons not designated.

[Kaiser Kirk]

Maddox : Is 11.27 : 1 a good L:B for a cruiser?  These aren't light combatants. The only real world I know of off-hand were Japanese, but they kept having to reinforce their ships. 

I decided to tweak the hull more to try to get more armor, but I sacrificed the seakeeping. On the second go-round I was thinking the seakeeping was important, as if you are sacrificing for speed and to gain an range advantage, the seakeeping would help you retain that in more seastates.  Of course speed continues to be of poor value when fouled, heavy seas, island combats, old engines, any waterline damage, if you don't have steam up, if the stacks are holed or concussion blows out a boiler, if boilers fail due to running at flank, etc etc etc.   

Still, here's the more armor option.

Bazibazouk III, Ottoman Cruiser laid down 1917 (Engine 1916)

Displacement:
   7,240 t light; 7,562 t standard; 8,518 t normal; 9,283 t full load

Dimensions: Length overall / water x beam x draught
   515.61 ft / 508.53 ft x 50.85 ft x 22.15 ft (normal load)
   157.16 m / 155.00 m x 15.50 m  x 6.75 m

Armament:
      8 - 6.50" / 165 mm guns (4x2 guns), 143.30lbs / 65.00kg shells, 1910 Model
     Breech loading guns in deck mounts with hoists
     on centreline ends, evenly spread, 2 raised mounts - superfiring
      4 - 2.95" / 75.0 mm guns in single mounts, 12.87lbs / 5.84kg shells, 1910 Model
     Quick firing guns in deck mounts
     on side ends, evenly spread
   Weight of broadside 1,198 lbs / 543 kg
   Shells per gun, main battery: 225
   12 - 18.0" / 457.2 mm above water torpedoes

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   3.54" / 90 mm   406.82 ft / 124.00 m   11.48 ft / 3.50 m
   Ends:   Unarmoured
     Main Belt covers 123 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   3.54" / 90 mm   0.98" / 25 mm      3.54" / 90 mm
   2nd:   0.79" / 20 mm   0.20" / 5 mm            -

   - Armour deck: 1.57" / 40 mm, Conning tower: 3.54" / 90 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 72,459 shp / 54,055 Kw = 31.00 kts
   Range 7,500nm at 14.00 kts
   Bunker at max displacement = 1,721 tons

Complement:
   443 - 576

Cost:
   £1.367 million / $5.468 million

Distribution of weights at normal displacement:
   Armament: 143 tons, 1.7 %
   Armour: 1,288 tons, 15.1 %
      - Belts: 669 tons, 7.8 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 76 tons, 0.9 %
      - Armour Deck: 512 tons, 6.0 %
      - Conning Tower: 32 tons, 0.4 %
   Machinery: 2,700 tons, 31.7 %
   Hull, fittings & equipment: 2,792 tons, 32.8 %
   Fuel, ammunition & stores: 1,278 tons, 15.0 %
   Miscellaneous weights: 316 tons, 3.7 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     6,574 lbs / 2,982 Kg = 48.0 x 6.5 " / 165 mm shells or 1.0 torpedoes
   Stability (Unstable if below 1.00): 1.20
   Metacentric height 2.5 ft / 0.8 m
   Roll period: 13.4 seconds
   Steadiness   - As gun platform (Average = 50 %): 51 %
         - Recoil effect (Restricted arc if above 1.00): 0.47
   Seaboat quality  (Average = 1.00): 1.01

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0.521
   Length to Beam Ratio: 10.00 : 1
   'Natural speed' for length: 22.55 kts
   Power going to wave formation at top speed: 59 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 12.00 degrees
   Stern overhang: 3.28 ft / 1.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      17.88 ft / 5.45 m
      - Forecastle (20 %):   17.88 ft / 5.45 m
      - Mid (50 %):      17.88 ft / 5.45 m
      - Quarterdeck (15 %):   17.88 ft / 5.45 m
      - Stern:      17.88 ft / 5.45 m
      - Average freeboard:   17.88 ft / 5.45 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 120.6 %
      - Above water (accommodation/working, high = better): 103.3 %
   Waterplane Area: 17,559 Square feet or 1,631 Square metres
   Displacement factor (Displacement / loading): 104 %
   Structure weight / hull surface area: 90 lbs/sq ft or 440 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.94
      - Longitudinal: 1.68
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is adequate

Main battery is A, B, Q, Y, X
75mm are in P1, 5 & S  1, 5
Torpedoes are in P2, 4 &  S 2, 4


100 tons Fire control
25 tons long range wireless
120 tons mines
12 tons torpedoes
59 tons construction reserve
----
316

[maddox]

For a French ship she's definitly "chunky", with that high BC (Nverse France has battleships with lower BC). But she's perfect in line with the Demarce series of Cruisers (all those can be traced back to 1 hull , the Rattlesnake by Carthaginian)

And the L/B ratio just makes for ships with less internal volume, the hull strength is made by the structure, and according to Springsharp, she's strong enough.
Of course, a good torpedo hit will break her back.

For France, Topkapi won't be accepted, her seakeeping is barely acceptable for a French DD (even the fastest French DD's have that, the leopards). But as export vessel with main working area, Med, Red and Black sea the "normal" seakeeping of 1.04 is good enough.

On the Japanese ships.
They not only made them slender for speed, but kept on stacking guns and armor on those. Combining with the modern, unknown qualities of welding it isn't a surprise they ran into trouble. 

[Korpen]

Little suggestion here: the design requirements called for 7500nm @ 12kts, while more range cannot hurt I for one would like to see people using 12kts for cruising speed to make comparison easier (or at least include the 12kts range) for people following this thread.

[maddox]

Good suggestion Korpen.

Added the exchange in range in Blue.  After that, I went playing with the desing to get 8000nm @ 12kts.
didn't like the results at all.

[mentat]

My earlier design which included the 10 x 165 mm is very similar to the Topkapi above - lower seakeeping Ok for Med etc

Only differences are a slightly lower L:B ratio 10.8:1 (540 x 50 x 20) , more misc wt (250 tons) and shorter range - 7500 @ 12 knots

the Guns are a bit tight fit - but seems to work

I was hoping same armament would fit on the beamier Bavarian design (since it seems optimal on all-round  performance) - puzzling that there seem to be some problems :(

[maddox]

Topkapi is based on the Demarce IIIb Volcano

But with the 165mm guns in twin mount and hoist  from the Demarce III.

[Kaiser Kirk]

I was hoping same armament would fit on the beamier Bavarian design (since it seems optimal on all-round  performance) - puzzling that there seem to be some problems :(

The original Bazibazouk was poked and prodded to hit those particular goals. The revised stats asked for a heavier weapons suite, more speed, more armor.

The change from 150mm to 165mm, even if keeping the magazine the same, takes 0.06 comp hull, a fairly big chunk. Dropping to 8x165mm only 'costs' 0.02 comp hull.
Then there is the new requirement for the guns to be armored the same as the belt.
I don't think it's a good one, but it is 19-25 tons and another 0.01 comp hull.

Now you come to the kicker, the additional speed. Right off the bat, the +1kt drives seakeeping below slow and steady roll.  Which makes it harder to engage at very long ranges. The additional engines drive the comp hull down another 0.12 and require more belt length for a total of  0.14.  Trying to recover the seakeeping costs a further 0.1.  

Now the vessel is down to 0.82 comp hull, and 6,220 flotation. It takes more than minor changes to bring that back in compliance.  

Thus the II and III versions, the former sacrificing armor to be a better long range gun platform and preserve the speed margin in more conditions, and the latter going with a short and deep hull, sacrificing seakeeping, but shrinking the area needing protection, and investing in a heavy deck and more side armor.

As for L:B, the ship design guidelines said the higher L:B are for 'smaller, faster' and I was making the apparently incorrect assumption that meant within your DD tech, not for 7250 ton cruisers. Edit : While the IJN cruisers may have been highly loaded, they also happened to be the examples I know of with L:B >11:1 in that size realm. Granted, IJN naval engineering less technical than some, which could also lead to more problems, but I would think the longer and the more mass, the difficult to compensate for forces at the extreme ends.

As for 7500@12kts... surfaced subs have been able to exceed 12 knots since 1905. Due to profiles, subs typically can see the warship prior to the warship seeing the sub. Theoretically, a sub could outpace a warship cruising at 12kt and lay in ambush. That's hard with a small speed margin, but the latest subs can hit 17kts. Edit : In other words, the more staff that becomes aware of what the latest Dutch subs can do, my design teams are of the growing opinion that 14-15kts is an appropriate cruise speed.

[Korpen]

Now you come to the kicker, the additional speed. Right off the bat, the +1kt drives seakeeping below slow and steady roll.  Which makes it harder to engage at very long ranges. The additional engines drive the comp hull down another 0.12 and require more belt length for a total of  0.14.  Trying to recover the seakeeping costs a further 0.1. 

On the seaboat number: It is a relative number, unlike most other in spring sharp that is absolute. That means that there is really no difference between the behaviour at sea between two identical hulls with different speeds even if SS gives them wildly different seakeeping (due to different speeds, SS use top speed for the formula). Related to this; the seaboat rating should really have nothing to do with the ability to maintain speed in rough seas, for ships of similar lines I think that it is really only size with matter there. Granted that higher seaboat rating most likely makes it more pleasant. But in this case I think it is hunting shadows to try and get the seaboat rating up as the ship have lost no seakeeping in the absolute sense.

As for 7500@12kts... surfaced subs have been able to exceed 12 knots since 1905. Due to profiles, subs typically can see the warship prior to the warship seeing the sub. Theoretically, a sub could outpace a warship cruising at 12kt and lay in ambush. That's hard with a small speed margin, but the latest subs can hit 17kts.

Intended operational cruising speed is not the same as the speed used in the springsharp IMO. I for one use 12kts even for my latest ships, which usually have significantly higher cruising speeds in use; but using the same speed in the reports makes it easier both to compare ships over time as well as between nations.

[Kaiser Kirk]

On the seaboat number:

Generally speaking, I agree that these are relative numbers. A destroyer with a 1.4 rating will still struggle more than a 1.0 BC in stormy weather.  Likewise the difference between a 1.19 and a 1.2 is likely not that huge.

In these cases I considered doing what I've done elsewhere, make a note at the bottom of at what speed that "slow and steady" is achieved, on in the case of some DDs with poor seakeeping at max speeds, when 1.0 is met.

In this case I went back and forth on need for seakeeping. A ship with 1.1 or 1.2 should be able to maintain speed in worse weather than a comparable vessel with a 1.0.  However. the area of operation is not known for particularly noteworthy bad seastates.

In this case, the change to 165mm and 31knts was driven by the stated desire to engage from beyond the range of the comparable Hapsburg and Iberian vessels.   Unfortunately that puts you out in the 16,000+ range while trying to operate at near max speed to maintain that separation. Hit rates will be very low to start with and having a steady gun platform even at maximum speed may be of appreciable benefit.

Intended operational cruising speed is not the same as the speed used in the springsharp IMO.

There we simply disagree. I view the number put in the cruise field as a declaration "this is our expected standard cruise speed", so I put the number in I expect to cruise at.