Light Auxiliaries

Desertfox · February 18, 2021, 02:09:50 PM

Light Auxiliaries OOB

Multi Purpose Colonial Auxiliary
4 x Uji class (1907)

Fast Transport
6 x Toph Maru I class
2 x Toph Maru II class

Minesweepers
30 x MS1 class

ASW Sloops
2 x Kaibokan II class (Experimental)
16 x A1 Class (1920)
2 x Kaibokan III (1920)

River Patrol Boats
3 x Toph Maru III class (1916)
8 x RPB-1 class

Desertfox · February 18, 2021, 02:10:12 PM

4 Built

Refit of the Uji class. main gun upgraded to 5" and the exploration areas changed to support an observation balloon and minesweeping gear added.

Uji class, Japan Multi-purpose Colonial Auxiliary Ship laid down 1907

Displacement:
698 t light; 725 t standard; 885 t normal; 1,013 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(270.00 ft / 270.00 ft) x 31.00 ft x (7.40 / 8.20 ft)
(82.30 m / 82.30 m) x 9.45 m x (2.26 / 2.50 m)

Armament:
1 - 5.00" / 127 mm 45.0 cal gun - 63.03lbs / 28.59kg shells, 200 per gun
Quick firing gun in deck mount, 1914 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, 300 per gun
Quick firing guns in deck mount, 1907 Model
1 x Triple mount on centreline, aft deck centre
1 raised mount
Weight of broadside 75 lbs / 34 kg

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.50" / 13 mm - -
2nd: 0.50" / 13 mm - -

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

Machinery:
Coal and oil fired boilers, complex reciprocating steam engines,
Direct drive, 2 shafts, 2,161 ihp / 1,612 Kw = 17.00 kts
Range 5,700nm at 10.00 kts
Bunker at max displacement = 288 tons (90% coal)

Complement:
80 - 105

Cost:
£0.061 million / $0.246 million

Distribution of weights at normal displacement:
Armament: 13 tons, 1.5 %
- Guns: 13 tons, 1.5 %
Armour: 4 tons, 0.5 %
- Armament: 2 tons, 0.3 %
- Conning Tower: 2 tons, 0.2 %
Machinery: 238 tons, 26.9 %
Hull, fittings & equipment: 318 tons, 35.9 %
Fuel, ammunition & stores: 187 tons, 21.1 %
Miscellaneous weights: 125 tons, 14.1 %
- On freeboard deck: 70 tons
- Above deck: 55 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,454 lbs / 660 Kg = 23.3 x 5.0 " / 127 mm shells or 0.7 torpedoes
Stability (Unstable if below 1.00): 1.34
Metacentric height 1.5 ft / 0.4 m
Roll period: 10.8 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.08
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): 0.500 / 0.516
Length to Beam Ratio: 8.71 : 1
'Natural speed' for length: 16.43 kts
Power going to wave formation at top speed: 42 %
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: 35.00 %, 11.00 ft / 3.35 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: 20.00 %, 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: 9.28 ft / 2.83 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 92.3 %
- Above water (accommodation/working, high = better): 119.5 %
Waterplane Area: 5,577 Square feet or 518 Square metres
Displacement factor (Displacement / loading): 138 %
Structure weight / hull surface area: 40 lbs/sq ft or 197 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.00
- Longitudinal: 1.19
- Overall: 1.01
Adequate machinery, storage, compartmentation space
Adequate accommodation and workspace room
Ship has slow, easy roll, a good, steady gun platform
Good seaboat, rides out heavy weather easily

25t - 1 x LR wireless,
25t - 1 x Experimental Radar,
5t - FC and Flagship Facilities
20t - Observation Balloon Equipment
20t - 2 x 5t boats
20t - 10 x Marines
10t - Minesweeping Gear

Desertfox · February 18, 2021, 02:10:50 PM

Toph Maru, Japan Fast Transport laid down 1913

Displacement:
400 t light; 411 t standard; 442 t normal; 466 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 / 5.63 ft)
(60.96 m / 60.96 m) x 8.23 m x (1.65 / 1.72 m)

Armament:
3 - 2.00" / 50.8 mm 45.0 cal guns - 4.03lbs / 1.83kg shells, 250 per gun
Quick firing guns in deck mount, 1913 Model
1 x Triple mount on centreline, forward deck forward
Weight of broadside 12 lbs / 5 kg

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

Machinery:
Oil fired boilers, steam turbines,
Electric motors, 2 shafts, 1,616 shp / 1,205 Kw = 17.00 kts
Range 2,500nm at 10.00 kts
Bunker at max displacement = 55 tons

Complement:
47 - 62

Cost:
£0.026 million / $0.103 million

Distribution of weights at normal displacement:
Armament: 2 tons, 0.5 %
- Guns: 2 tons, 0.5 %
Armour: 2 tons, 0.5 %
- Armament: 2 tons, 0.5 %
Machinery: 63 tons, 14.3 %
Hull, fittings & equipment: 157 tons, 35.5 %
Fuel, ammunition & stores: 41 tons, 9.3 %
Miscellaneous weights: 176 tons, 39.9 %
- Hull below water: 16 tons
- On freeboard deck: 150 tons
- Above deck: 10 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,222 lbs / 554 Kg = 305.4 x 2.0 " / 51 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 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.01
Seaboat quality (Average = 1.00): 1.05

Hull form characteristics:
Hull has a flush deck,
a normal bow and a cruiser stern
Block coefficient (normal/deep): 0.530 / 0.536
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: 30.00 %, 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: 25.00 %, 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: 7.36 ft / 2.24 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 53.4 %
- Above water (accommodation/working, high = better): 104.9 %
Waterplane Area: 3,699 Square feet or 344 Square metres
Displacement factor (Displacement / loading): 142 %
Structure weight / hull surface area: 31 lbs/sq ft or 152 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.97
- Longitudinal: 1.23
- Overall: 1.00
Excellent machinery, storage, compartmentation space
Adequate accommodation and workspace room

10t - Spare
150t - 150 Marines or supplies
16t - Electric Drive

Desertfox · February 18, 2021, 02:12:15 PM

A variant of the Toph Maru class, adds another triple 2" Gatling aft, an observation balloon, minesweeping gear, and replaces the troop and transport capabilities with tender facilities. Allows them to support small amounts of ships in undeveloped areas, including two flotillas (20) of MTBs.

Toph Maru II, Japan Multi-purpose Tender laid down 1913

Displacement:
400 t light; 412 t standard; 442 t normal; 465 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 / 5.62 ft)
(60.96 m / 60.96 m) x 8.23 m x (1.65 / 1.71 m)

Armament:
6 - 2.00" / 50.8 mm 45.0 cal guns - 4.03lbs / 1.83kg shells, 250 per gun
Quick firing guns in deck mounts, 1913 Model
2 x Triple mounts on centreline, evenly spread
Weight of broadside 24 lbs / 11 kg

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

Machinery:
Oil fired boilers, steam turbines,
Electric motors, 2 shafts, 1,616 shp / 1,205 Kw = 17.00 kts
Range 2,400nm at 10.00 kts
Bunker at max displacement = 53 tons

Complement:
47 - 62

Cost:
£0.026 million / $0.106 million

Distribution of weights at normal displacement:
Armament: 4 tons, 1.0 %
- Guns: 4 tons, 1.0 %
Armour: 4 tons, 1.0 %
- Armament: 4 tons, 1.0 %
Machinery: 63 tons, 14.3 %
Hull, fittings & equipment: 158 tons, 35.7 %
Fuel, ammunition & stores: 42 tons, 9.5 %
Miscellaneous weights: 170 tons, 38.5 %
- Hull below water: 20 tons
- On freeboard deck: 150 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,183 lbs / 537 Kg = 295.8 x 2.0 " / 51 mm shells or 1.0 torpedoes
Stability (Unstable if below 1.00): 1.26
Metacentric height 1.1 ft / 0.3 m
Roll period: 11.0 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.03
Seaboat quality (Average = 1.00): 1.05

Hull form characteristics:
Hull has a flush deck,
a normal bow and a cruiser stern
Block coefficient (normal/deep): 0.530 / 0.536
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): 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 %, 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: 25.00 %, 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: 7.36 ft / 2.24 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 56.0 %
- Above water (accommodation/working, high = better): 104.9 %
Waterplane Area: 3,699 Square feet or 344 Square metres
Displacement factor (Displacement / loading): 141 %
Structure weight / hull surface area: 32 lbs/sq ft or 155 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.97
- Longitudinal: 1.26
- Overall: 1.00
Excellent machinery, storage, compartmentation space
Adequate accommodation and workspace room

20t - Observation Balloon
10t - Minesweeping Gear
120t - Out-of-port Resupply
20t - Electric Drive

Desertfox · February 18, 2021, 02:14:53 PM

No 1, Japan Minesweeper laid down 1914

Displacement:
200 t light; 206 t standard; 225 t normal; 240 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(151.59 ft / 150.00 ft) x 21.00 ft x (5.00 / 5.25 ft)
(46.20 m / 45.72 m) x 6.40 m x (1.52 / 1.60 m)

Armament:
6 - 2.00" / 50.8 mm 45.0 cal guns - 4.03lbs / 1.83kg shells, 170 per gun
Quick firing guns in deck mounts, 1914 Model
2 x Triple mounts on centreline, evenly spread
Weight of broadside 24 lbs / 11 kg

Machinery:
Oil fired boilers, steam turbines,
Electric motors, 2 shafts, 1,173 shp / 875 Kw = 17.00 kts
Range 2,400nm at 10.00 kts
Bunker at max displacement = 33 tons

Complement:
28 - 37

Cost:
£0.019 million / $0.075 million

Distribution of weights at normal displacement:
Armament: 4 tons, 1.9 %
- Guns: 4 tons, 1.9 %
Machinery: 45 tons, 20.1 %
Hull, fittings & equipment: 83 tons, 36.9 %
Fuel, ammunition & stores: 25 tons, 11.3 %
Miscellaneous weights: 67 tons, 29.8 %
- Hull below water: 32 tons
- On freeboard deck: 35 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
398 lbs / 180 Kg = 99.5 x 2.0 " / 51 mm shells or 0.4 torpedoes
Stability (Unstable if below 1.00): 1.16
Metacentric height 0.6 ft / 0.2 m
Roll period: 11.1 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.09
Seaboat quality (Average = 1.00): 1.01

Hull form characteristics:
Hull has a flush deck,
a normal bow and a cruiser stern
Block coefficient (normal/deep): 0.500 / 0.508
Length to Beam Ratio: 7.14 : 1
'Natural speed' for length: 12.25 kts
Power going to wave formation at top speed: 60 %
Trim (Max stability = 0, Max steadiness = 100): 69
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 %, 9.00 ft / 2.74 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: 25.00 %, 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: 7.20 ft / 2.19 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 87.3 %
- Above water (accommodation/working, high = better): 99.9 %
Waterplane Area: 2,099 Square feet or 195 Square metres
Displacement factor (Displacement / loading): 132 %
Structure weight / hull surface area: 27 lbs/sq ft or 131 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.92
- Longitudinal: 2.22
- Overall: 1.00
Adequate machinery, storage, compartmentation space
Adequate accommodation and workspace room
Ship has slow, easy roll, a good, steady gun platform

20t - Out-of-port Resupply
10t - Observation Balloon
25t - Minesweeping Gear
12t - Electric Drive

Desertfox · June 17, 2021, 10:23:20 AM

Japan is starting 1910 ASW Tech in H1/1917. As part of that a couple of improved Kaibokans will be built as testbeds for ASW equipment and tech. Main change other than the misc weight is the addition of electric drive.

Kaibokan II, Japan ASW Testbed laid down 1917

Displacement:
299 t light; 307 t standard; 374 t normal; 427 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(172.12 ft / 170.00 ft) x 27.00 ft x (5.70 / 6.33 ft)
(52.46 m / 51.82 m) x 8.23 m x (1.74 / 1.93 m)

Armament:
1 - 2.00" / 50.8 mm 45.0 cal gun - 4.03lbs / 1.83kg shells, 100 per gun
Quick firing gun in deck mount, 1917 Model
1 x Single mount on centreline, forward deck centre
Weight of broadside 4 lbs / 2 kg

Machinery:
Oil fired boilers, steam turbines,
Electric motors, 1 shaft, 1,558 shp / 1,162 Kw = 17.00 kts
Range 3,000nm at 14.00 kts
Bunker at max displacement = 120 tons

Complement:
42 - 55

Cost:
£0.034 million / $0.136 million

Distribution of weights at normal displacement:
Armament: 1 tons, 0.2 %
- Guns: 1 tons, 0.2 %
Machinery: 57 tons, 15.3 %
Hull, fittings & equipment: 145 tons, 38.7 %
Fuel, ammunition & stores: 74 tons, 19.9 %
Miscellaneous weights: 97 tons, 26.0 %
- Hull below water: 14 tons
- On freeboard deck: 83 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,217 lbs / 552 Kg = 304.2 x 2.0 " / 51 mm shells or 1.0 torpedoes
Stability (Unstable if below 1.00): 1.24
Metacentric height 1.0 ft / 0.3 m
Roll period: 11.1 seconds
Steadiness - As gun platform (Average = 50 %): 71 %
- Recoil effect (Restricted arc if above 1.00): 0.01
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 / 0.514
Length to Beam Ratio: 6.30 : 1
'Natural speed' for length: 13.04 kts
Power going to wave formation at top speed: 58 %
Trim (Max stability = 0, Max steadiness = 100): 59
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: 31.00 %, 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: 14.00 %, 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: 9.20 ft / 2.80 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 55.4 %
- Above water (accommodation/working, high = better): 133.3 %
Waterplane Area: 2,940 Square feet or 273 Square metres
Displacement factor (Displacement / loading): 175 %
Structure weight / hull surface area: 32 lbs/sq ft or 157 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.90
- Longitudinal: 2.60
- 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
20t - Observation Balloon Equipment
20t - Basic + Enhanced Hydrophone Suite
10t - Minesweeping Gear
8t - Misc ASW Weapons
14t - Electric Drive

Desertfox · June 17, 2021, 10:40:23 AM

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

Desertfox · October 27, 2021, 10:35:59 AM

With Japan now having two major rivers as borders there will be an additional emphasis on river boats. This is version of the Toph Maru class, designed to support and repair river patrol boats and MTBs up to 40t.

Toph Maru III, Japan River Boat Tender laid down 1916

Displacement:
401 t light; 414 t standard; 442 t normal; 464 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 / 5.61 ft)
(60.96 m / 60.96 m) x 8.23 m x (1.65 / 1.71 m)

Armament:
6 - 2.00" / 50.8 mm 45.0 cal guns - 4.03lbs / 1.83kg shells, 300 per gun
Quick firing guns in deck mounts, 1916 Model
2 x Triple mounts on centreline, evenly spread
Weight of broadside 24 lbs / 11 kg

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

- Conning towers: Forward 0.50" / 13 mm, Aft 0.50" / 13 mm

Machinery:
Oil fired boilers, steam turbines,
Electric motors, 2 shafts, 1,616 shp / 1,205 Kw = 17.00 kts
Range 2,500nm at 10.00 kts
Bunker at max displacement = 49 tons

Complement:
47 - 62

Cost:
£0.039 million / $0.156 million

Distribution of weights at normal displacement:
Armament: 4 tons, 1.0 %
- Guns: 4 tons, 1.0 %
Armour: 3 tons, 0.8 %
- Armament: 2 tons, 0.5 %
- Conning Towers: 1 tons, 0.3 %
Machinery: 60 tons, 13.6 %
Hull, fittings & equipment: 158 tons, 35.8 %
Fuel, ammunition & stores: 40 tons, 9.1 %
Miscellaneous weights: 175 tons, 39.6 %
- Hull below water: 20 tons
- On freeboard deck: 150 tons
- Above deck: 5 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,219 lbs / 553 Kg = 304.7 x 2.0 " / 51 mm shells or 1.0 torpedoes
Stability (Unstable if below 1.00): 1.24
Metacentric height 1.0 ft / 0.3 m
Roll period: 11.1 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.03
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 / 0.536
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): 53.9 %
- Above water (accommodation/working, high = better): 104.9 %
Waterplane Area: 3,699 Square feet or 344 Square metres
Displacement factor (Displacement / loading): 142 %
Structure weight / hull surface area: 32 lbs/sq ft or 156 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.98
- Longitudinal: 1.24
- Overall: 1.00
Excellent machinery, storage, compartmentation space
Adequate accommodation and workspace room

5t - Flagship Accommodations
20t - Observation Balloon
80t - MTB support
50t - Out of port resupply
20t - Electric Drive

Desertfox · April 07, 2022, 12:28:21 PM

Building off the sailing ship as ASW sloop idea, these are modified versions of the reconnaissance schooners, designed for ASW work. They have a better engine, longer range, and light armament.

A-1 class, Japan ASW Schooner laid down 1921

Displacement:
201 t light; 205 t standard; 215 t normal; 222 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(171.23 ft / 170.00 ft) x 20.00 ft x (4.70 / 4.82 ft)
(52.19 m / 51.82 m) x 6.10 m x (1.43 / 1.47 m)

Armament:
4 - 1.00" / 25.4 mm 45.0 cal guns - 0.50lbs / 0.23kg shells, 250 per gun
Machine guns in deck mounts, 1921 Model
2 x Twin mounts on centreline, evenly spread
Weight of broadside 2 lbs / 1 kg

Machinery:
Oil fired boilers, steam turbines,
Electric motors, 1 shaft, 1,038 shp / 774 Kw = 17.00 kts
Range 1,500nm at 10.00 kts
Bunker at max displacement = 17 tons

Complement:
27 - 36

Cost:
£0.031 million / $0.124 million

Distribution of weights at normal displacement:
Armament: 0 tons, 0.2 %
- Guns: 0 tons, 0.2 %
Machinery: 36 tons, 16.7 %
Hull, fittings & equipment: 72 tons, 33.3 %
Fuel, ammunition & stores: 14 tons, 6.5 %
Miscellaneous weights: 93 tons, 43.3 %
- Hull below water: 16 tons
- On freeboard deck: 74 tons
- Above deck: 3 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
429 lbs / 195 Kg = 857.9 x 1.0 " / 25 mm shells or 0.6 torpedoes
Stability (Unstable if below 1.00): 1.12
Metacentric height 0.6 ft / 0.2 m
Roll period: 11.3 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.01
Seaboat quality (Average = 1.00): 1.01

Hull form characteristics:
Hull has a flush deck,
a normal bow and a cruiser stern
Block coefficient (normal/deep): 0.470 / 0.474
Length to Beam Ratio: 8.50 : 1
'Natural speed' for length: 13.04 kts
Power going to wave formation at top speed: 53 %
Trim (Max stability = 0, Max steadiness = 100): 49
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 %, 7.00 ft / 2.13 m, 6.00 ft / 1.83 m
- Forward deck: 30.00 %, 6.00 ft / 1.83 m, 6.00 ft / 1.83 m
- Aft deck: 35.00 %, 6.00 ft / 1.83 m, 6.00 ft / 1.83 m
- Quarter deck: 15.00 %, 6.00 ft / 1.83 m, 6.00 ft / 1.83 m
- Average freeboard: 6.08 ft / 1.85 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 64.0 %
- Above water (accommodation/working, high = better): 89.3 %
Waterplane Area: 2,109 Square feet or 196 Square metres
Displacement factor (Displacement / loading): 129 %
Structure weight / hull surface area: 23 lbs/sq ft or 110 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.88
- Longitudinal: 1.14
- Overall: 0.90
Caution: Hull subject to strain in open-sea
Excellent machinery, storage, compartmentation space
Cramped accommodation and workspace room

10t - Auxiliary sail rigging
25t - LR Wireless
25t - Experimental Radar
20t - Enhanced ASW Suite
4t - 20x90kg DC, 2xASW Paravanes
9t - Electric Motor

Desertfox · April 07, 2022, 12:29:00 PM

Aux ASW Sloops

Kaibokan III, Japan ASW Sloop laid down 1921

Displacement:
301 t light; 308 t standard; 361 t normal; 403 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(170.00 ft / 170.00 ft) x 27.00 ft x (5.50 / 5.98 ft)
(51.82 m / 51.82 m) x 8.23 m x (1.68 / 1.82 m)

Armament:
4 - 1.00" / 25.4 mm 70.0 cal guns - 0.56lbs / 0.25kg shells, 200 per gun
Machine guns in deck mounts, 1921 Model
2 x Twin mounts on centreline, evenly spread
Weight of broadside 2 lbs / 1 kg

Machinery:
Oil fired boilers, steam turbines,
Electric cruising motors plus geared drives, 2 shafts, 1,527 shp / 1,139 Kw = 17.00 kts
Range 2,700nm at 14.00 kts
Bunker at max displacement = 95 tons

Complement:
40 - 53

Cost:
£0.046 million / $0.185 million

Distribution of weights at normal displacement:
Armament: 1 tons, 0.2 %
- Guns: 1 tons, 0.2 %
Machinery: 53 tons, 14.6 %
Hull, fittings & equipment: 144 tons, 40.0 %
Fuel, ammunition & stores: 60 tons, 16.7 %
Miscellaneous weights: 103 tons, 28.6 %
- Hull below water: 14 tons
- On freeboard deck: 89 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,265 lbs / 574 Kg = 2,529.9 x 1.0 " / 25 mm shells or 1.0 torpedoes
Stability (Unstable if below 1.00): 1.20
Metacentric height 1.0 ft / 0.3 m
Roll period: 11.4 seconds
Steadiness - As gun platform (Average = 50 %): 71 %
- 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 / 0.513
Length to Beam Ratio: 6.30 : 1
'Natural speed' for length: 13.04 kts
Power going to wave formation at top speed: 58 %
Trim (Max stability = 0, Max steadiness = 100): 59
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: 31.00 %, 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: 16.00 %, 10.00 ft / 3.05 m, 10.00 ft / 3.05 m
- Quarter deck: 33.00 %, 7.00 ft / 2.13 m, 7.00 ft / 2.13 m
- Average freeboard: 9.26 ft / 2.82 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 53.3 %
- Above water (accommodation/working, high = better): 145.6 %
Waterplane Area: 3,058 Square feet or 284 Square metres
Displacement factor (Displacement / loading): 171 %
Structure weight / hull surface area: 32 lbs/sq ft or 155 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.89
- Longitudinal: 2.66
- 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

1t - FC
25t - Experimental Radar
20t - Observation Balloon Equipment
25t - Enhanced Hydrophone Suite
10t - Minesweeping gear
8t - ASW Weapons (40 DC)
14t - Electric Drive