Non-naval/Non-combatant Auxiliaries

[Desertfox]

Non-naval/Non-combatant Auxiliaries

Diplomatic/Intelligence
2 x Tatsuta Maru class (1910)

Hospital/Flagship
2 x Tachibana Maru class (1914)

Intelligence
10 x "Fishing Boat 42" class (1912)
4 x "Schooner 13" class (1913)

Rescue/Balloon Observation
12 x Kaibokan class (1913)
4 x Kaibokan E Class

Test Platform
Hiroshi Sato (1916)

[Desertfox]

Tatsuta Maru, Japan Diplomatic Ship laid down 1910

Displacement:
   3,200 t light; 3,288 t standard; 4,420 t normal; 5,325 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (350.00 ft / 350.00 ft) x 50.00 ft x (17.00 / 19.67 ft)
   (106.68 m / 106.68 m) x 15.24 m  x (5.18 / 5.99 m)

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   0.50" / 13 mm   350.00 ft / 106.68 m   10.00 ft / 3.05 m
     Main Belt covers 154 % of normal length

Machinery:
   Coal and oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 12,243 shp / 9,133 Kw = 21.00 kts
   Range 7,590nm at 14.00 kts
   Bunker at max displacement = 2,037 tons (90% coal)

Complement:
   270 - 352

Cost:
   £0.189 million / $0.757 million

Distribution of weights at normal displacement:
   Armament: 0 tons, 0.0 %
   Armour: 65 tons, 1.5 %
      - Belts: 65 tons, 1.5 %
   Machinery: 551 tons, 12.5 %
   Hull, fittings & equipment: 1,234 tons, 27.9 %
   Fuel, ammunition & stores: 1,220 tons, 27.6 %
   Miscellaneous weights: 1,350 tons, 30.5 %
      - Hull below water: 500 tons
      - Hull above water: 500 tons
      - On freeboard deck: 200 tons
      - Above deck: 150 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     9,076 lbs / 4,117 Kg = 84.0 x 6 " / 152 mm shells or 1.9 torpedoes
   Stability (Unstable if below 1.00): 1.43
   Metacentric height 3.3 ft / 1.0 m
   Roll period: 11.6 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0.00
   Seaboat quality  (Average = 1.00): 1.87

Hull form characteristics:
   Hull has rise aft of midbreak,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.520 / 0.542
   Length to Beam Ratio: 7.00 : 1
   'Natural speed' for length: 18.71 kts
   Power going to wave formation at top speed: 53 %
   Trim (Max stability = 0, Max steadiness = 100): 38
   Bow angle (Positive = bow angles forward): 0.00 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 %,  20.00 ft / 6.10 m,  17.00 ft / 5.18 m
      - Forward deck:   30.00 %,  17.00 ft / 5.18 m,  15.00 ft / 4.57 m
      - Aft deck:   25.00 %,  17.00 ft / 5.18 m,  17.00 ft / 5.18 m
      - Quarter deck:   15.00 %,  17.00 ft / 5.18 m,  17.00 ft / 5.18 m
      - Average freeboard:      17.06 ft / 5.20 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 66.0 %
      - Above water (accommodation/working, high = better): 137.9 %
   Waterplane Area: 11,876 Square feet or 1,103 Square metres
   Displacement factor (Displacement / loading): 176 %
   Structure weight / hull surface area: 64 lbs/sq ft or 312 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.91
      - Longitudinal: 2.30
      - Overall: 1.00
   Excellent machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform
   Excellent seaboat, comfortable, rides out heavy weather easily

50t - "Flag" accommodations
50t - 2  x long-range wireless
25t - Experimental "radar" (1905)
25t - Extra navigation/surveying equipment
200t - 4 x 20 ton tenders (25 passengers each)
500t - 100 Passenger accommodations
500t - Resupply support

[Desertfox]

During the war the Japanese Fleet was commanded from the diplomatic ship Tatsuta Maru at the fleet anchorage. The use of the ship proved successful but tied the ship down from its regular duties. In order to free the two diplomatic ships for their regular duties, the Japanese fleet will build two dedicated ships who will do double duty as hospital ships.

Tachibana Maru, Japan Hospital Ship/C&C laid down 1914

Displacement:
   2,901 t light; 2,972 t standard; 3,561 t normal; 4,033 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (340.00 ft / 340.00 ft) x 50.00 ft x (14.10 / 15.53 ft)
   (103.63 m / 103.63 m) x 15.24 m  x (4.30 / 4.73 m)

Machinery:
   Oil fired boilers, steam turbines,
   Electric motors, 2 shafts, 10,927 shp / 8,152 Kw = 21.00 kts
   Range 7,100nm at 14.00 kts
   Bunker at max displacement = 1,060 tons

Complement:
   229 - 299

Cost:
   £0.204 million / $0.817 million

Distribution of weights at normal displacement:
   Armament: 0 tons, 0.0 %
   Machinery: 421 tons, 11.8 %
   Hull, fittings & equipment: 1,040 tons, 29.2 %
   Fuel, ammunition & stores: 660 tons, 18.5 %
   Miscellaneous weights: 1,440 tons, 40.4 %
      - Hull below water: 400 tons
      - Hull above water: 500 tons
      - On freeboard deck: 250 tons
      - Above deck: 290 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     6,951 lbs / 3,153 Kg = 64.4 x 6 " / 152 mm shells or 1.7 torpedoes
   Stability (Unstable if below 1.00): 1.29
   Metacentric height 2.8 ft / 0.8 m
   Roll period: 12.6 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0.00
   Seaboat quality  (Average = 1.00): 1.50

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.520 / 0.535
   Length to Beam Ratio: 6.80 : 1
   'Natural speed' for length: 18.44 kts
   Power going to wave formation at top speed: 53 %
   Trim (Max stability = 0, Max steadiness = 100): 47
   Bow angle (Positive = bow angles forward): 0.00 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 %,  17.00 ft / 5.18 m,  14.00 ft / 4.27 m
      - Forward deck:   30.00 %,  14.00 ft / 4.27 m,  14.00 ft / 4.27 m
      - Aft deck:   25.00 %,  14.00 ft / 4.27 m,  14.00 ft / 4.27 m
      - Quarter deck:   15.00 %,  14.00 ft / 4.27 m,  14.00 ft / 4.27 m
      - Average freeboard:      14.36 ft / 4.38 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 66.7 %
      - Above water (accommodation/working, high = better): 134.3 %
   Waterplane Area: 11,537 Square feet or 1,072 Square metres
   Displacement factor (Displacement / loading): 156 %
   Structure weight / hull surface area: 61 lbs/sq ft or 297 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.94
      - Longitudinal: 1.74
      - Overall: 1.00
   Excellent machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform
   Excellent seaboat, comfortable, rides out heavy weather easily

200t - Flag accommodations
50t - 2  x long-range wireless
25t - Experimental Radar
25t - Extra navigation equipment
200t - 4 x 20 ton rescue boats
40t - Observation Balloon
500t - 100 bed hospital
290t - Out-of-port resupply
110t - Electric Drive

[Desertfox]

"Fishing Boat 42", Japan Junk (espionage ship) laid down 1900 (Engine 1912)

Displacement:
   95 t light; 97 t standard; 99 t normal; 100 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (80.00 ft / 80.00 ft) x 32.00 ft x (2.70 / 2.73 ft)
   (24.38 m / 24.38 m) x 9.75 m  x (0.82 / 0.83 m)

Armament:
      1 - 0.50" / 12.7 mm 45.0 cal gun - 0.06lbs / 0.03kg shells, 300 per gun
     Machine gun in deck mount, 1900 Model
     1 x Single mount on centreline amidships (forward deck)
      4 - 0.30" / 7.6 mm 45.0 cal guns - 0.01lbs / 0.01kg shells, 150 per gun
     Breech loading guns in deck mounts, 1900 Model
     4 x Single mounts on sides, evenly spread
      Weight of broadside 0 lbs / 0 kg

Machinery:
   Petrol Internal combustion motors,
   Direct drive, 2 shafts, 54 ihp / 41 Kw = 7.90 kts
   Range 420nm at 7.90 kts
   Bunker at max displacement = 3 tons

Complement:
   15 - 20

Cost:
   £0.004 million / $0.015 million

Distribution of weights at normal displacement:
   Armament: 0 tons, 0.1 %
      - Guns: 0 tons, 0.1 %
   Machinery: 3 tons, 3.5 %
   Hull, fittings & equipment: 42 tons, 43.0 %
   Fuel, ammunition & stores: 4 tons, 3.8 %
   Miscellaneous weights: 49 tons, 49.6 %
      - Hull below water: 15 tons
      - Hull above water: 4 tons
      - On freeboard deck: 25 tons
      - Above deck: 5 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     755 lbs / 342 Kg = 12,075.9 x 0.5 " / 13 mm shells or 1.3 torpedoes
   Stability (Unstable if below 1.00): 2.29
   Metacentric height 3.2 ft / 1.0 m
   Roll period: 7.5 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0.00
   Seaboat quality  (Average = 1.00): 1.61

Hull form characteristics:
   Hull has low forecastle,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.500 / 0.502
   Length to Beam Ratio: 2.50 : 1
   'Natural speed' for length: 8.94 kts
   Power going to wave formation at top speed: 43 %
   Trim (Max stability = 0, Max steadiness = 100): 44
   Bow angle (Positive = bow angles forward): 0.00 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 %,  7.00 ft / 2.13 m,  4.00 ft / 1.22 m
      - Forward deck:   30.00 %,  5.00 ft / 1.52 m,  5.00 ft / 1.52 m
      - Aft deck:   30.00 %,  5.00 ft / 1.52 m,  5.00 ft / 1.52 m
      - Quarter deck:   20.00 %,  5.00 ft / 1.52 m,  7.00 ft / 2.13 m
      - Average freeboard:      5.24 ft / 1.60 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 34.1 %
      - Above water (accommodation/working, high = better): 108.3 %
   Waterplane Area: 1,706 Square feet or 158 Square metres
   Displacement factor (Displacement / loading): 175 %
   Structure weight / hull surface area: 23 lbs/sq ft or 111 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.86
      - Longitudinal: 3.61
      - Overall: 1.00
   Excellent machinery, storage, compartmentation space
   Adequate 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

21t- Junk sail rig
10t - SR wireless
18t - Espionage equipment

2 separate petrol motors
1 x 50 hp powers boat, max speed 7.7kts
1 x 4 hp powers wireless

[Desertfox]

Spy ship, disguised as a schooner. Hidden gun for self-defense can be replaced by twin 14" torpedo tubes.

Boat #13, Japan Intelligence Gathering laid down 1914

Displacement:
   199 t light; 204 t standard; 214 t normal; 223 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (151.23 ft / 150.00 ft) x 20.00 ft x (5.00 / 5.15 ft)
   (46.10 m / 45.72 m) x 6.10 m  x (1.52 / 1.57 m)

Armament:
      3 - 2.00" / 50.8 mm 45.0 cal guns - 4.03lbs / 1.83kg shells, 150 per gun
     Quick firing guns in deck mount, 1914 Model
     1 x Triple mount on centreline amidships (forward deck)
      Weight of broadside 12 lbs / 5 kg

Machinery:
   Coal and oil fired boilers, complex reciprocating steam engines,
   Electric motors, 1 shaft, 518 ihp / 386 Kw = 14.00 kts
   Range 1,000nm at 10.00 kts
   Bunker at max displacement = 19 tons (50% coal)

Complement:
   27 - 36

Cost:
   £0.015 million / $0.062 million

Distribution of weights at normal displacement:
   Armament: 2 tons, 1.0 %
      - Guns: 2 tons, 1.0 %
   Machinery: 32 tons, 15.1 %
   Hull, fittings & equipment: 66 tons, 30.8 %
   Fuel, ammunition & stores: 16 tons, 7.3 %
   Miscellaneous weights: 98 tons, 45.7 %
      - Hull below water: 15 tons
      - On freeboard deck: 79 tons
      - Above deck: 4 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     433 lbs / 197 Kg = 108.3 x 2.0 " / 51 mm shells or 0.6 torpedoes
   Stability (Unstable if below 1.00): 1.18
   Metacentric height 0.6 ft / 0.2 m
   Roll period: 10.8 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.03
   Seaboat quality  (Average = 1.00): 1.17

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.500 / 0.504
   Length to Beam Ratio: 7.50 : 1
   'Natural speed' for length: 12.25 kts
   Power going to wave formation at top speed: 49 %
   Trim (Max stability = 0, Max steadiness = 100): 43
   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 %,  7.00 ft / 2.13 m,  5.00 ft / 1.52 m
      - Forward deck:   30.00 %,  5.00 ft / 1.52 m,  5.00 ft / 1.52 m
      - Aft deck:   25.00 %,  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:      5.24 ft / 1.60 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 61.0 %
      - Above water (accommodation/working, high = better): 67.8 %
   Waterplane Area: 1,921 Square feet or 178 Square metres
   Displacement factor (Displacement / loading): 127 %
   Structure weight / hull surface area: 24 lbs/sq ft or 117 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.97
      - Longitudinal: 1.24
      - Overall: 1.00
   Excellent machinery, storage, compartmentation space
   Cramped accommodation and workspace room

10t - Two-mast schooner sail rigging
25t - LR Wireless
25t - Experimental Radar
20t - Out-of-port resupply
5t - Spy stuff
4t - Camouflage
8t - Electric Motor

[Desertfox]

Dedicated scout and picket boat with a secondary minesweeping role.

Kaibokan, Japan Rescue/Balloon Observation/Minesweeper  laid down 1913

Displacement:
   300 t light; 308 t standard; 387 t normal; 450 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (170.00 ft / 170.00 ft) x 27.00 ft x (5.90 / 6.66 ft)
   (51.82 m / 51.82 m) x 8.23 m  x (1.80 / 2.03 m)

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 1 shaft, 1,589 shp / 1,185 Kw = 17.00 kts
   Range 3,000nm at 14.00 kts
   Bunker at max displacement = 143 tons

Complement:
   43 - 56

Cost:
   £0.021 million / $0.084 million

Distribution of weights at normal displacement:
   Armament: 0 tons, 0.0 %
   Machinery: 62 tons, 16.1 %
   Hull, fittings & equipment: 146 tons, 37.6 %
   Fuel, ammunition & stores: 87 tons, 22.5 %
   Miscellaneous weights: 92 tons, 23.8 %
      - On freeboard deck: 92 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     1,268 lbs / 575 Kg = 11.7 x 6 " / 152 mm shells or 1.0 torpedoes
   Stability (Unstable if below 1.00): 1.23
   Metacentric height 1.0 ft / 0.3 m
   Roll period: 11.2 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.00
   Seaboat quality  (Average = 1.00): 1.20

Hull form characteristics:
   Hull has low quarterdeck ,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.500 / 0.516
   Length to Beam Ratio: 6.30 : 1
   'Natural speed' for length: 13.04 kts
   Power going to wave formation at top speed: 59 %
   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 (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   30.00 %,  12.00 ft / 3.66 m,  10.00 ft / 3.05 m
      - Forward deck:   20.00 %,  10.00 ft / 3.05 m,  10.00 ft / 3.05 m
      - Aft deck:   15.00 %,  10.00 ft / 3.05 m,  10.00 ft / 3.05 m
      - Quarter deck:   35.00 %,  7.00 ft / 2.13 m,  7.00 ft / 2.13 m
      - Average freeboard:      9.19 ft / 2.80 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 53.5 %
      - Above water (accommodation/working, high = better): 130.2 %
   Waterplane Area: 2,940 Square feet or 273 Square metres
   Displacement factor (Displacement / loading): 179 %
   Structure weight / hull surface area: 32 lbs/sq ft or 157 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.90
      - Longitudinal: 2.59
      - Overall: 1.00
   Excellent machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform
   Good seaboat, rides out heavy weather easily

25t - Experimental Radar
25t - LR Wireless
20t - Observation Balloon Equipment
10t - Rescue Equipment/Facilities
10t - Minesweeping Gear
2t - Signaling Rockets

[Desertfox]

One of the Toph Maru IIIs will be finished to a different configuration. The armament and supplies will be replaced with experimental equipment to support two radio-guided 20t MTBs. The project will be led by the CEO of Future Industries, Asami Sato.

Hiroshi Sato, Japan Experimental Mothership laid down 1916

Displacement:
   401 t light; 410 t standard; 442 t normal; 467 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (200.00 ft / 200.00 ft) x 27.00 ft x (5.40 / 5.64 ft)
   (60.96 m / 60.96 m) x 8.23 m  x (1.65 / 1.72 m)

Machinery:
   Oil fired boilers, steam turbines,
   Electric motors, 2 shafts, 1,616 shp / 1,205 Kw = 17.00 kts
   Range 2,900nm at 10.00 kts
   Bunker at max displacement = 57 tons

Complement:
   47 - 62

Cost:
   £0.037 million / $0.147 million

Distribution of weights at normal displacement:
   Armament: 0 tons, 0.0 %
   Machinery: 60 tons, 13.6 %
   Hull, fittings & equipment: 156 tons, 35.3 %
   Fuel, ammunition & stores: 40 tons, 9.1 %
   Miscellaneous weights: 185 tons, 41.9 %
      - Hull below water: 20 tons
      - On freeboard deck: 140 tons
      - Above deck: 25 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     1,290 lbs / 585 Kg = 11.9 x 6 " / 152 mm shells or 1.1 torpedoes
   Stability (Unstable if below 1.00): 1.22
   Metacentric height 1.0 ft / 0.3 m
   Roll period: 11.3 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.00
   Seaboat quality  (Average = 1.00): 1.03

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.530 / 0.537
   Length to Beam Ratio: 7.41 : 1
   'Natural speed' for length: 14.14 kts
   Power going to wave formation at top speed: 52 %
   Trim (Max stability = 0, Max steadiness = 100): 48
   Bow angle (Positive = bow angles forward): 0.00 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 %,  10.00 ft / 3.05 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:   15.00 %,  7.00 ft / 2.13 m,  7.00 ft / 2.13 m
      - Average freeboard:      7.24 ft / 2.21 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 50.5 %
      - Above water (accommodation/working, high = better): 104.9 %
   Waterplane Area: 3,699 Square feet or 344 Square metres
   Displacement factor (Displacement / loading): 145 %
   Structure weight / hull surface area: 31 lbs/sq ft or 151 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.98
      - Longitudinal: 1.20
      - Overall: 1.00
   Excellent machinery, storage, compartmentation space
   Adequate accommodation and workspace room

25t - LR Wireless
40t - Experimental stuff
20t - Observation Balloon
80t - 2 x 20t MTB support
20t - Electric Drive