Japanese Ship Designs 1915+

[Desertfox]

As an engineer, I just hate having to deliberately design inefficiencies into a design, but if that's what it takes to get a working design so be it.

***

Auxiliary river patrol boat, can support itself.   

No 1, Japan River Patrol Boat laid down 1917

Displacement:
   99 t light; 103 t standard; 109 t normal; 113 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (101.23 ft / 100.00 ft) x 15.00 ft x (5.40 / 5.57 ft)
   (30.86 m / 30.48 m) x 4.57 m  x (1.65 / 1.70 m)

Armament:
      3 - 2.00" / 50.8 mm 45.0 cal guns - 4.03lbs / 1.83kg shells, 200 per gun
     Quick firing guns in deck mount, 1917 Model
     1 x Triple mount on centreline, forward deck forward
      Weight of broadside 12 lbs / 5 kg

Machinery:
   Oil fired boilers, steam turbines,
   Electric motors, 2 shafts, 912 shp / 681 Kw = 17.00 kts
   Range 1,200nm at 10.00 kts
   Bunker at max displacement = 11 tons

Complement:
   16 - 21

Cost:
   £0.016 million / $0.064 million

Distribution of weights at normal displacement:
   Armament: 2 tons, 2.0 %
      - Guns: 2 tons, 2.0 %
   Machinery: 33 tons, 30.8 %
   Hull, fittings & equipment: 41 tons, 37.5 %
   Fuel, ammunition & stores: 9 tons, 8.6 %
   Miscellaneous weights: 23 tons, 21.1 %
      - Hull below water: 8 tons
      - On freeboard deck: 14 tons
      - Above deck: 1 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     125 lbs / 57 Kg = 31.2 x 2.0 " / 51 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.16
   Metacentric height 0.4 ft / 0.1 m
   Roll period: 10.2 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.14
   Seaboat quality  (Average = 1.00): 1.04

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.470 / 0.475
   Length to Beam Ratio: 6.67 : 1
   'Natural speed' for length: 10.00 kts
   Power going to wave formation at top speed: 71 %
   Trim (Max stability = 0, Max steadiness = 100): 48
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   15.00 %,  7.00 ft / 2.13 m,  7.00 ft / 2.13 m
      - Forward deck:   30.00 %,  7.00 ft / 2.13 m,  7.00 ft / 2.13 m
      - Aft deck:   35.00 %,  7.00 ft / 2.13 m,  7.00 ft / 2.13 m
      - Quarter deck:   20.00 %,  7.00 ft / 2.13 m,  7.00 ft / 2.13 m
      - Average freeboard:      7.00 ft / 2.13 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 114.4 %
      - Above water (accommodation/working, high = better): 81.1 %
   Waterplane Area: 973 Square feet or 90 Square metres
   Displacement factor (Displacement / loading): 113 %
   Structure weight / hull surface area: 21 lbs/sq ft or 101 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.80
      - Longitudinal: 7.56
      - Overall: 1.00
   Cramped machinery, storage, compartmentation space
   Cramped accommodation and workspace room

1t - FC
10t - Out-of-port Supplies
4t - Marine/Mortar Squad
8t - Electric Drive

[Kaiser Kirk]

As an engineer, I just hate having to deliberately design inefficiencies into a design, but if that's what it takes to get a working design so be it.

Springsharp "charges" to much for destroyer machinery.
We recognize that and have special rules for "Destroyer architecture" that both reduce the comp hull needed, and then give a speed boost on top of that.
The intent being to allow modeling ships similar to historic destroyers with the modeling tool available.

To avoid arguments over if a ship 'counts', there's the machinery rule.
I will observe that the weight of Turbo electric gear should actually be tied to the SHP, which is what it's conveying, not engine weight.

Anyhow, you wanted a gunboat, you didn't feel like using the cruiser rules to make it.
Fast destroyers pay penalties in comp hull and seakeeping, so you found a work around and chose an inefficient engine to make a slow destroyer,
so you could shoehorn it under the destroyer architecture. 

It's a neat trick, legit under the rules, and gives you a gunboat with a heck of a bang for the buck.

[TacCovert4]

From a realism standpoint, the VTE has the benefit of being 'easier' to build, IE not needing highly specialized machinery or technical training that you would to build turbines.  They're also something far more common on commercial shipping, so you can have some certainty of both repair parts and skilled mechanics in the wider world, which is useful for maintenance in colonies.

[Desertfox]

Cheap simple destroyer escort.

Abukuma, Japan ASW Frigate laid down 1917

Displacement:
   269 t light; 281 t standard; 319 t normal; 349 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (201.76 ft / 200.00 ft) x 21.00 ft x (7.00 / 7.42 ft)
   (61.50 m / 60.96 m) x 6.40 m  x (2.13 / 2.26 m)

Armament:
      1 - 5.00" / 127 mm 45.0 cal gun - 63.03lbs / 28.59kg shells, 130 per gun
     Quick firing gun in deck mount, 1917 Model
     1 x Single mount on centreline, forward deck centre
      3 - 2.00" / 50.8 mm 50.0 cal guns - 4.23lbs / 1.92kg shells, 150 per gun
     Quick firing guns in deck mount, 1917 Model
     1 x Triple mount on centreline, aft deck centre
      Weight of broadside 76 lbs / 34 kg

Machinery:
   Coal and oil fired boilers, complex reciprocating steam engines,
   Direct drive, 2 shafts, 4,698 ihp / 3,505 Kw = 24.00 kts
   Range 3,400nm at 10.00 kts
   Bunker at max displacement = 68 tons (40% coal)

Complement:
   37 - 49

Cost:
   £0.064 million / $0.257 million

Distribution of weights at normal displacement:
   Armament: 13 tons, 4.2 %
      - Guns: 13 tons, 4.2 %
   Machinery: 158 tons, 49.6 %
   Hull, fittings & equipment: 80 tons, 24.9 %
   Fuel, ammunition & stores: 50 tons, 15.6 %
   Miscellaneous weights: 18 tons, 5.6 %
      - On freeboard deck: 17 tons
      - Above deck: 1 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     98 lbs / 44 Kg = 1.6 x 5.0 " / 127 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.23
   Metacentric height 0.7 ft / 0.2 m
   Roll period: 10.5 seconds
   Steadiness   - As gun platform (Average = 50 %): 75 %
         - Recoil effect (Restricted arc if above 1.00): 0.31
   Seaboat quality  (Average = 1.00): 1.07

Hull form characteristics:
   Hull has rise forward of midbreak,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.380 / 0.393
   Length to Beam Ratio: 9.52 : 1
   'Natural speed' for length: 14.14 kts
   Power going to wave formation at top speed: 63 %
   Trim (Max stability = 0, Max steadiness = 100): 70
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   32.00 %,  10.00 ft / 3.05 m,  10.00 ft / 3.05 m
      - Forward deck:   35.00 %,  10.00 ft / 3.05 m,  10.00 ft / 3.05 m
      - Aft deck:   18.00 %,  5.00 ft / 1.52 m,  5.00 ft / 1.52 m
      - Quarter deck:   15.00 %,  5.00 ft / 1.52 m,  5.00 ft / 1.52 m
      - Average freeboard:      8.35 ft / 2.55 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 172.0 %
      - Above water (accommodation/working, high = better): 108.6 %
   Waterplane Area: 2,551 Square feet or 237 Square metres
   Displacement factor (Displacement / loading): 51 %
   Structure weight / hull surface area: 19 lbs/sq ft or 92 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.66
      - Overall: 0.56
   Cramped machinery, storage, compartmentation space
   Adequate accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

17t for ASW Equipment
1t for 1908 FC

[snip]

   Machinery: 158 tons, 49.6 %
   

Looks like there is a bit of an issue here

[Desertfox]

I really hate that rule. I swear it was at 50, tried to fiddle with range, went back to original range and didn't realize it hadn't changed. This should be fixed and cheaper.

Abukuma, Japan ASW Frigate laid down 1917

Displacement:
   252 t light; 264 t standard; 303 t normal; 335 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (191.76 ft / 190.00 ft) x 21.00 ft x (7.00 / 7.45 ft)
   (58.45 m / 57.91 m) x 6.40 m  x (2.13 / 2.27 m)

Armament:
      1 - 5.00" / 127 mm 45.0 cal gun - 63.03lbs / 28.59kg shells, 140 per gun
     Quick firing gun in deck mount, 1917 Model
     1 x Single mount on centreline, forward deck centre
      3 - 2.00" / 50.8 mm 45.0 cal guns - 4.03lbs / 1.83kg shells, 150 per gun
     Quick firing guns in deck mount, 1917 Model
     1 x Triple mount on centreline, aft deck centre
      Weight of broadside 75 lbs / 34 kg

Machinery:
   Coal and oil fired boilers, complex reciprocating steam engines,
   Direct drive, 2 shafts, 4,715 ihp / 3,517 Kw = 24.00 kts
   Range 1,700nm at 14.00 kts
   Bunker at max displacement = 70 tons (20% coal)

Complement:
   36 - 47

Cost:
   £0.061 million / $0.245 million

Distribution of weights at normal displacement:
   Armament: 13 tons, 4.3 %
      - Guns: 13 tons, 4.3 %
   Machinery: 152 tons, 50.0 %
   Hull, fittings & equipment: 71 tons, 23.6 %
   Fuel, ammunition & stores: 51 tons, 16.8 %
   Miscellaneous weights: 16 tons, 5.3 %
      - On freeboard deck: 15 tons
      - Above deck: 1 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     83 lbs / 38 Kg = 1.3 x 5.0 " / 127 mm shells or 0.1 torpedoes
   Stability (Unstable if below 1.00): 1.27
   Metacentric height 0.7 ft / 0.2 m
   Roll period: 10.3 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.24
   Seaboat quality  (Average = 1.00): 1.00

Hull form characteristics:
   Hull has raised forecastle,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.380 / 0.394
   Length to Beam Ratio: 9.05 : 1
   'Natural speed' for length: 13.78 kts
   Power going to wave formation at top speed: 65 %
   Trim (Max stability = 0, Max steadiness = 100): 70
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   44.00 %,  10.00 ft / 3.05 m,  10.00 ft / 3.05 m
      - Forward deck:   35.00 %,  7.00 ft / 2.13 m,  7.00 ft / 2.13 m
      - Aft deck:   6.00 %,  7.00 ft / 2.13 m,  7.00 ft / 2.13 m
      - Quarter deck:   15.00 %,  7.00 ft / 2.13 m,  7.00 ft / 2.13 m
      - Average freeboard:      8.32 ft / 2.54 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 173.6 %
      - Above water (accommodation/working, high = better): 89.4 %
   Waterplane Area: 2,424 Square feet or 225 Square metres
   Displacement factor (Displacement / loading): 49 %
   Structure weight / hull surface area: 18 lbs/sq ft or 88 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.74
      - Overall: 0.56
   Cramped machinery, storage, compartmentation space
   Cramped accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

1t for 1908 FC
15t for ASW Equipment

[snip]

I'm not really sure I see the point of doing a new-build design for this role. Why wont an older ship do?

[Desertfox]

I'm not exactly swimming in old ships with plenty of reserve misc weight.

[Desertfox]

Refit of the Kamikazes. Converted completely to oil fired, 3" guns replaced with 5" guns, twin torpedo tubes replaced with triples, and FC added. Cost is 0.04 BP and $0.18 per ship.

Kamikaze, Japan Destroyer laid down 1904

Displacement:
   427 t light; 448 t standard; 487 t normal; 518 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (252.12 ft / 250.00 ft) x 24.00 ft x (7.10 / 7.40 ft)
   (76.84 m / 76.20 m) x 7.32 m  x (2.16 / 2.25 m)

Armament:
      2 - 5.00" / 127 mm 45.0 cal guns - 63.03lbs / 28.59kg shells, 100 per gun
     Quick firing guns in deck mounts, 1916 Model
     2 x Single mounts on centreline, evenly spread
      12 - 2.00" / 50.8 mm 45.0 cal guns - 4.03lbs / 1.83kg shells, 150 per gun
     Quick firing guns in deck mounts, 1904 Model
     4 x Triple mounts on sides, evenly spread
      Weight of broadside 174 lbs / 79 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.00" / 25 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 8,936 shp / 6,666 Kw = 27.00 kts
   Range 1,900nm at 10.00 kts
   Bunker at max displacement = 70 tons
     Caution: Delicate, lightweight machinery

Complement:
   51 - 67

Cost:
   £0.061 million / $0.244 million

Distribution of weights at normal displacement:
   Armament: 31 tons, 6.3 %
      - Guns: 31 tons, 6.3 %
   Armour: 5 tons, 1.1 %
      - Armament: 5 tons, 1.1 %
   Machinery: 266 tons, 54.7 %
   Hull, fittings & equipment: 110 tons, 22.6 %
   Fuel, ammunition & stores: 60 tons, 12.3 %
   Miscellaneous weights: 15 tons, 3.1 %
      - On freeboard deck: 12 tons
      - Above deck: 3 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     103 lbs / 46 Kg = 1.6 x 5.0 " / 127 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.19
   Metacentric height 0.8 ft / 0.2 m
   Roll period: 11.2 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.39
   Seaboat quality  (Average = 1.00): 0.83

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.400 / 0.409
   Length to Beam Ratio: 10.42 : 1
   'Natural speed' for length: 15.81 kts
   Power going to wave formation at top speed: 63 %
   Trim (Max stability = 0, Max steadiness = 100): 84
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   30.00 %,  12.00 ft / 3.66 m,  8.00 ft / 2.44 m
      - Forward deck:   30.00 %,  8.00 ft / 2.44 m,  8.00 ft / 2.44 m
      - Aft deck:   25.00 %,  8.00 ft / 2.44 m,  8.00 ft / 2.44 m
      - Quarter deck:   15.00 %,  8.00 ft / 2.44 m,  8.00 ft / 2.44 m
      - Average freeboard:      8.48 ft / 2.58 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 193.7 %
      - Above water (accommodation/working, high = better): 106.0 %
   Waterplane Area: 3,693 Square feet or 343 Square metres
   Displacement factor (Displacement / loading): 28 %
   Structure weight / hull surface area: 21 lbs/sq ft or 105 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 0.94
      - Overall: 0.53
   Cramped machinery, storage, compartmentation space
   Adequate accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform
   Poor seaboat, wet and uncomfortable, reduced performance in heavy weather

3t - 1908 FC
12t - 6 18" TT

[Desertfox]

Basically the same, armament upgrade and converted to full oil firing.

Umikaze, Japan Destroyer laid down 1910

Displacement:
   590 t light; 621 t standard; 662 t normal; 695 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (292.64 ft / 290.00 ft) x 27.00 ft x (7.40 / 7.64 ft)
   (89.20 m / 88.39 m) x 8.23 m  x (2.26 / 2.33 m)

Armament:
      3 - 5.00" / 127 mm 45.0 cal guns - 63.03lbs / 28.59kg shells, 150 per gun
     Quick firing guns in deck mounts, 1910 Model
     3 x Single mounts on centreline, evenly spread
      6 - 2.00" / 50.8 mm 45.0 cal guns - 4.03lbs / 1.83kg shells, 150 per gun
     Quick firing guns in deck mounts, 1910 Model
     2 x Triple mounts on sides amidships
      Weight of broadside 213 lbs / 97 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.50" / 13 mm         -               -

   - Conning towers: Forward 1.00" / 25 mm, Aft 0.00" / 0 mm

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 15,563 shp / 11,610 Kw = 30.00 kts
   Range 2,300nm at 10.00 kts
   Bunker at max displacement = 74 tons

Complement:
   64 - 84

Cost:
   £0.078 million / $0.311 million

Distribution of weights at normal displacement:
   Armament: 37 tons, 5.6 %
      - Guns: 37 tons, 5.6 %
   Armour: 5 tons, 0.8 %
      - Armament: 4 tons, 0.6 %
      - Conning Tower: 2 tons, 0.2 %
   Machinery: 335 tons, 50.5 %
   Hull, fittings & equipment: 197 tons, 29.7 %
   Fuel, ammunition & stores: 72 tons, 10.9 %
   Miscellaneous weights: 16 tons, 2.4 %
      - Hull above water: 4 tons
      - On freeboard deck: 12 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     189 lbs / 86 Kg = 3.0 x 5.0 " / 127 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.15
   Metacentric height 0.9 ft / 0.3 m
   Roll period: 11.9 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.39
   Seaboat quality  (Average = 1.00): 0.98

Hull form characteristics:
   Hull has raised forecastle,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.400 / 0.407
   Length to Beam Ratio: 10.74 : 1
   'Natural speed' for length: 17.03 kts
   Power going to wave formation at top speed: 64 %
   Trim (Max stability = 0, Max steadiness = 100): 71
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   25.00 %,  15.00 ft / 4.57 m,  15.00 ft / 4.57 m
      - Forward deck:   30.00 %,  10.00 ft / 3.05 m,  10.00 ft / 3.05 m
      - Aft deck:   30.00 %,  10.00 ft / 3.05 m,  10.00 ft / 3.05 m
      - Quarter deck:   15.00 %,  10.00 ft / 3.05 m,  10.00 ft / 3.05 m
      - Average freeboard:      11.25 ft / 3.43 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 179.6 %
      - Above water (accommodation/working, high = better): 137.8 %
   Waterplane Area: 4,820 Square feet or 448 Square metres
   Displacement factor (Displacement / loading): 47 %
   Structure weight / hull surface area: 25 lbs/sq ft or 123 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.49
      - Overall: 0.56
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform
   Poor seaboat, wet and uncomfortable, reduced performance in heavy weather

4t - 1908 FC
12t - 6 18" TT

[snip]

Kamikaze, Japan Destroyer laid down 1904

These seem a poor match for any modern or close to modern destroyer. Why not drop some of the 2" guns (and maybe one 5") and give them enough Misc weight to become the subhunter you are looking at a bit up the thread, and then build some more up to date destroyers?

[Desertfox]

Because while they might not be great against modern destroyers, they are absolutely murderous against MTBs, and my neighbors have ALOT of those around.

[Desertfox]

Upgraded version of the Izokazes. Upgrades torpedoes from 3 twin 18" tubes to 2 triple 21" tubes, adds depth charges, and 500nm of range. The flagship version only drops one 5" gun and the DCs, and keeps the full torpedo armament. 

Improved Izokaze class, Japan Destroyer laid down 1917

Displacement:
   800 t light; 840 t standard; 954 t normal; 1,045 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (302.64 ft / 300.00 ft) x 29.00 ft x (10.10 / 10.71 ft)
   (92.25 m / 91.44 m) x 8.84 m  x (3.08 / 3.26 m)

Armament:
      4 - 5.00" / 127 mm 45.0 cal guns - 63.03lbs / 28.59kg shells, 120 per gun
     Quick firing guns in deck mounts, 1917 Model
     4 x Single mounts on centreline, evenly spread
      1 raised mount
      12 - 2.00" / 50.8 mm 45.0 cal guns - 4.03lbs / 1.83kg shells, 150 per gun
     Quick firing guns in deck mounts, 1917 Model
     4 x Triple mounts on sides, evenly spread
      Weight of broadside 301 lbs / 136 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.10" / 3 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 20,489 shp / 15,285 Kw = 30.50 kts
   Range 3,400nm at 14.00 kts
   Bunker at max displacement = 206 tons

Complement:
   85 - 111

Cost:
   £0.199 million / $0.796 million

Distribution of weights at normal displacement:
   Armament: 52 tons, 5.5 %
      - Guns: 52 tons, 5.5 %
   Armour: 1 tons, 0.1 %
      - Armament: 1 tons, 0.1 %
   Machinery: 477 tons, 50.0 %
   Hull, fittings & equipment: 240 tons, 25.2 %
   Fuel, ammunition & stores: 154 tons, 16.2 %
   Miscellaneous weights: 29 tons, 3.0 %
      - On freeboard deck: 24 tons
      - Above deck: 5 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     241 lbs / 109 Kg = 3.9 x 5.0 " / 127 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.20
   Metacentric height 1.1 ft / 0.3 m
   Roll period: 11.6 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0.44
   Seaboat quality  (Average = 1.00): 1.00

Hull form characteristics:
   Hull has raised forecastle,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.380 / 0.393
   Length to Beam Ratio: 10.34 : 1
   'Natural speed' for length: 17.32 kts
   Power going to wave formation at top speed: 64 %
   Trim (Max stability = 0, Max steadiness = 100): 71
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   34.00 %,  15.00 ft / 4.57 m,  15.00 ft / 4.57 m
      - Forward deck:   30.00 %,  10.00 ft / 3.05 m,  10.00 ft / 3.05 m
      - Aft deck:   21.00 %,  10.00 ft / 3.05 m,  10.00 ft / 3.05 m
      - Quarter deck:   15.00 %,  10.00 ft / 3.05 m,  10.00 ft / 3.05 m
      - Average freeboard:      11.70 ft / 3.57 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 176.5 %
      - Above water (accommodation/working, high = better): 118.1 %
   Waterplane Area: 5,284 Square feet or 491 Square metres
   Displacement factor (Displacement / loading): 57 %
   Structure weight / hull surface area: 28 lbs/sq ft or 135 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.54
      - Overall: 0.56
   Cramped machinery, storage, compartmentation space
   Adequate accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

5t - 1908 FC
18t - 6  x 21"  Torpedoes
6t - 24 x DC

***

Izokaze class, Japan Destroyer laid down 1917

Displacement:
   802 t light; 840 t standard; 954 t normal; 1,045 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (302.64 ft / 300.00 ft) x 29.00 ft x (10.10 / 10.71 ft)
   (92.25 m / 91.44 m) x 8.84 m  x (3.08 / 3.26 m)

Armament:
      3 - 5.00" / 127 mm 45.0 cal guns - 63.03lbs / 28.59kg shells, 140 per gun
     Quick firing guns in deck mounts, 1917 Model
     3 x Single mounts on centreline, evenly spread
      12 - 2.00" / 50.8 mm 45.0 cal guns - 4.03lbs / 1.83kg shells, 150 per gun
     Quick firing guns in deck mounts, 1917 Model
     4 x Triple mounts on sides, evenly spread
      Weight of broadside 238 lbs / 108 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.10" / 3 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 20,489 shp / 15,285 Kw = 30.50 kts
   Range 3,400nm at 14.00 kts
   Bunker at max displacement = 206 tons

Complement:
   85 - 111

Cost:
   £0.195 million / $0.778 million

Distribution of weights at normal displacement:
   Armament: 42 tons, 4.4 %
      - Guns: 42 tons, 4.4 %
   Armour: 1 tons, 0.1 %
      - Armament: 1 tons, 0.1 %
   Machinery: 480 tons, 50.3 %
   Hull, fittings & equipment: 236 tons, 24.7 %
   Fuel, ammunition & stores: 152 tons, 15.9 %
   Miscellaneous weights: 44 tons, 4.6 %
      - On freeboard deck: 40 tons
      - Above deck: 4 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     246 lbs / 112 Kg = 3.9 x 5.0 " / 127 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.22
   Metacentric height 1.1 ft / 0.3 m
   Roll period: 11.5 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.30
   Seaboat quality  (Average = 1.00): 1.00

Hull form characteristics:
   Hull has raised forecastle,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.380 / 0.393
   Length to Beam Ratio: 10.34 : 1
   'Natural speed' for length: 17.32 kts
   Power going to wave formation at top speed: 64 %
   Trim (Max stability = 0, Max steadiness = 100): 70
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   33.00 %,  15.00 ft / 4.57 m,  15.00 ft / 4.57 m
      - Forward deck:   30.00 %,  10.00 ft / 3.05 m,  10.00 ft / 3.05 m
      - Aft deck:   22.00 %,  10.00 ft / 3.05 m,  10.00 ft / 3.05 m
      - Quarter deck:   15.00 %,  10.00 ft / 3.05 m,  10.00 ft / 3.05 m
      - Average freeboard:      11.65 ft / 3.55 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 174.8 %
      - Above water (accommodation/working, high = better): 118.1 %
   Waterplane Area: 5,284 Square feet or 491 Square metres
   Displacement factor (Displacement / loading): 58 %
   Structure weight / hull surface area: 27 lbs/sq ft or 130 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.48
      - Overall: 0.55
   Cramped machinery, storage, compartmentation space
   Adequate accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

6t - 1908 FC + Flag facilities
18t - 6  x 21"  Torpedoes
20t - Observation Balloon Equipment

[Desertfox]

Japan has plenty of undeveloped anchorages and short-legged destroyers. A dedicated Destroyer/Sub tender is in order. Can support a full squadron of 12 subs or destroyers, while freeing up the big Kobayashi Marus for use with the fleet.

Seta Maru, Japan Destroyer/Submarine Tender laid down 1917

Displacement:
   1,997 t light; 2,064 t standard; 2,666 t normal; 3,148 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (302.47 ft / 300.00 ft) x 40.00 ft x (14.40 / 16.43 ft)
   (92.19 m / 91.44 m) x 12.19 m  x (4.39 / 5.01 m)

Armament:
      2 - 5.00" / 127 mm 45.0 cal guns - 63.03lbs / 28.59kg shells, 140 per gun
     Breech loading guns in deck and hoist mounts, 1917 Model
     2 x Single mounts on centreline ends, evenly spread
      12 - 2.00" / 50.8 mm 45.0 cal guns - 4.03lbs / 1.83kg shells, 150 per gun
     Breech loading guns in deck mounts, 1917 Model
     4 x Triple mounts on sides, evenly spread
      Weight of broadside 174 lbs / 79 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.00" / 25 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 4,148 shp / 3,094 Kw = 17.00 kts
   Range 9,700nm at 14.00 kts
   Bunker at max displacement = 1,084 tons

Complement:
   185 - 241

Cost:
   £0.193 million / $0.770 million

Distribution of weights at normal displacement:
   Armament: 42 tons, 1.6 %
      - Guns: 42 tons, 1.6 %
   Armour: 5 tons, 0.2 %
      - Armament: 5 tons, 0.2 %
   Machinery: 152 tons, 5.7 %
   Hull, fittings & equipment: 643 tons, 24.1 %
   Fuel, ammunition & stores: 669 tons, 25.1 %
   Miscellaneous weights: 1,155 tons, 43.3 %
      - Hull below water: 500 tons
      - Hull above water: 500 tons
      - On freeboard deck: 100 tons
      - Above deck: 55 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     4,272 lbs / 1,938 Kg = 68.4 x 5.0 " / 127 mm shells or 1.4 torpedoes
   Stability (Unstable if below 1.00): 1.35
   Metacentric height 2.2 ft / 0.7 m
   Roll period: 11.4 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0.09
   Seaboat quality  (Average = 1.00): 1.54

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.540 / 0.559
   Length to Beam Ratio: 7.50 : 1
   'Natural speed' for length: 17.32 kts
   Power going to wave formation at top speed: 45 %
   Trim (Max stability = 0, Max steadiness = 100): 46
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  14.00 ft / 4.27 m,  9.00 ft / 2.74 m
      - Forward deck:   30.00 %,  9.00 ft / 2.74 m,  9.00 ft / 2.74 m
      - Aft deck:   35.00 %,  9.00 ft / 2.74 m,  9.00 ft / 2.74 m
      - Quarter deck:   15.00 %,  9.00 ft / 2.74 m,  9.00 ft / 2.74 m
      - Average freeboard:      9.40 ft / 2.87 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 65.3 %
      - Above water (accommodation/working, high = better): 76.9 %
   Waterplane Area: 8,297 Square feet or 771 Square metres
   Displacement factor (Displacement / loading): 166 %
   Structure weight / hull surface area: 54 lbs/sq ft or 263 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.97
      - Longitudinal: 1.33
      - Overall: 1.00
   Excellent machinery, storage, compartmentation space
   Cramped accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform
   Excellent seaboat, comfortable, can fire her guns in the heaviest weather

55t - Long-range Wireless/Experimental Radar/FC
80t - 2 x 20 ton Boats
20t - Observation Balloon
1000t - Out-of-Port Resupply

[Desertfox]

Dedicated torpedo attack destroyer. Loses a 5" gun, two 2" gatlings, and the ASW suite, in exchange for twice the torpedo tubes.

Improved Sakura class, Japan Destroyer laid down 1917

Displacement:
   740 t light; 773 t standard; 879 t normal; 964 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (302.64 ft / 300.00 ft) x 27.00 ft x (10.00 / 10.60 ft)
   (92.25 m / 91.44 m) x 8.23 m  x (3.05 / 3.23 m)

Armament:
      3 - 5.00" / 127 mm 45.0 cal guns - 63.03lbs / 28.59kg shells, 130 per gun
     Quick firing guns in deck mounts, 1917 Model
     3 x Single mounts on centreline ends, majority aft
      1 raised mount aft - superfiring
      6 - 2.00" / 50.8 mm 45.0 cal guns - 4.03lbs / 1.83kg shells, 150 per gun
     Quick firing guns in deck mounts, 1917 Model
     4 x Triple mounts on sides, evenly spread
      Weight of broadside 213 lbs / 97 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.10" / 3 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 18,993 shp / 14,169 Kw = 30.40 kts
   Range 3,300nm at 14.00 kts
   Bunker at max displacement = 191 tons

Complement:
   79 - 104

Cost:
   £0.178 million / $0.712 million

Distribution of weights at normal displacement:
   Armament: 37 tons, 4.2 %
      - Guns: 37 tons, 4.2 %
   Armour: 1 tons, 0.1 %
      - Armament: 1 tons, 0.1 %
   Machinery: 441 tons, 50.1 %
   Hull, fittings & equipment: 222 tons, 25.2 %
   Fuel, ammunition & stores: 139 tons, 15.8 %
   Miscellaneous weights: 40 tons, 4.5 %
      - On freeboard deck: 36 tons
      - Above deck: 4 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     226 lbs / 102 Kg = 3.6 x 5.0 " / 127 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.17
   Metacentric height 0.9 ft / 0.3 m
   Roll period: 11.7 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.43
   Seaboat quality  (Average = 1.00): 1.00

Hull form characteristics:
   Hull has raised forecastle,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.380 / 0.393
   Length to Beam Ratio: 11.11 : 1
   'Natural speed' for length: 17.32 kts
   Power going to wave formation at top speed: 63 %
   Trim (Max stability = 0, Max steadiness = 100): 70
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  15.00 ft / 4.57 m,  15.00 ft / 4.57 m
      - Forward deck:   30.00 %,  10.00 ft / 3.05 m,  10.00 ft / 3.05 m
      - Aft deck:   35.00 %,  10.00 ft / 3.05 m,  10.00 ft / 3.05 m
      - Quarter deck:   15.00 %,  10.00 ft / 3.05 m,  10.00 ft / 3.05 m
      - Average freeboard:      11.00 ft / 3.35 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 173.5 %
      - Above water (accommodation/working, high = better): 118.3 %
   Waterplane Area: 4,920 Square feet or 457 Square metres
   Displacement factor (Displacement / loading): 57 %
   Structure weight / hull surface area: 26 lbs/sq ft or 127 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.41
      - Overall: 0.55
   Cramped machinery, storage, compartmentation space
   Adequate accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

4t - 1908 FC
36t - 12  x 21"  Torpedoes