Colonial Gunboats

[Desertfox]

Order of Battle

Tenryu class (1913)
Tenryu
Tatsuta

Surabaya class (1915)
Surabaya
Makassar

Kuma class (1917)
Kuma
Tama

[Desertfox]

Multi-purpose littoral combatant. It can be deployed as a raider with enough supplies to self-deploy, used as a minelayer with up to 140 mines, can carry marines and landing craft as a fast transport, or fitted out with an observation balloon and used as a fleet scout. Primarily, these are to be used as colonial gunboats, with a small marine contingent (80t), a small minelaying capability (40t), and an observation balloon (20t).

Tenryu, Japan Littoral Combattant  laid down 1913

Displacement:
   1,399 t light; 1,462 t standard; 1,795 t normal; 2,062 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (342.64 ft / 340.00 ft) x 42.00 ft x (10.00 / 11.03 ft)
   (104.44 m / 103.63 m) x 12.80 m  x (3.05 / 3.36 m)

Armament:
      5 - 5.00" / 127 mm 45.0 cal guns - 63.03lbs / 28.59kg shells, 140 per gun
     Quick firing guns in deck and hoist mounts, 1913 Model
     3 x Single mounts on centreline ends, majority aft
      1 raised mount aft - superfiring
     2 x Single mounts on sides amidships
      6 - 2.00" / 50.8 mm 45.0 cal guns - 4.03lbs / 1.83kg shells, 200 per gun
     Quick firing guns in deck mounts, 1913 Model
     2 x Triple mounts on centreline, evenly spread
      Weight of broadside 339 lbs / 154 kg

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

Machinery:
   Coal and oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 11,530 shp / 8,601 Kw = 24.00 kts
   Range 5,200nm at 14.00 kts
   Bunker at max displacement = 600 tons (40% coal)

Complement:
   137 - 179

Cost:
   £0.159 million / $0.637 million

Distribution of weights at normal displacement:
   Armament: 89 tons, 5.0 %
      - Guns: 89 tons, 5.0 %
   Armour: 13 tons, 0.7 %
      - Armament: 13 tons, 0.7 %
   Machinery: 469 tons, 26.1 %
   Hull, fittings & equipment: 632 tons, 35.2 %
   Fuel, ammunition & stores: 397 tons, 22.1 %
   Miscellaneous weights: 195 tons, 10.9 %
      - Hull above water: 140 tons
      - On freeboard deck: 20 tons
      - Above deck: 35 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     1,716 lbs / 778 Kg = 27.5 x 5.0 " / 127 mm shells or 0.7 torpedoes
   Stability (Unstable if below 1.00): 1.24
   Metacentric height 2.0 ft / 0.6 m
   Roll period: 12.4 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.23
   Seaboat quality  (Average = 1.00): 1.05

Hull form characteristics:
   Hull has raised forecastle,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.440 / 0.458
   Length to Beam Ratio: 8.10 : 1
   'Natural speed' for length: 18.44 kts
   Power going to wave formation at top speed: 54 %
   Trim (Max stability = 0, Max steadiness = 100): 67
   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:   40.00 %,  15.00 ft / 4.57 m,  15.00 ft / 4.57 m
      - Forward deck:   30.00 %,  9.00 ft / 2.74 m,  9.00 ft / 2.74 m
      - Aft deck:   15.00 %,  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:      11.40 ft / 3.47 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 109.6 %
      - Above water (accommodation/working, high = better): 113.1 %
   Waterplane Area: 9,036 Square feet or 839 Square metres
   Displacement factor (Displacement / loading): 124 %
   Structure weight / hull surface area: 53 lbs/sq ft or 259 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.87
      - Longitudinal: 1.19
      - Overall: 0.90
   Adequate machinery, storage, compartmentation space
   Adequate accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

10t - 1908 Fire Control
25t - LR Wireless
10t - 4 x 18" Torpedo Tubes
10t - Mine-sweeping Gear
140t - Mines/Supplies/Marines/Observation Balloon etc

[Desertfox]

Surabaya

Surabaya, Japan Colonial Gunboat laid down 1915

Displacement:
   2,100 t light; 2,278 t standard; 2,442 t normal; 2,573 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (300.00 ft / 300.00 ft) x 49.00 ft x (11.40 / 11.86 ft)
   (91.44 m / 91.44 m) x 14.94 m  x (3.47 / 3.62 m)

Armament:
      4 - 8.00" / 203 mm 45.0 cal guns - 258.18lbs / 117.11kg shells, 140 per gun
     Breech loading guns in turret on barbette mounts, 1915 Model
     2 x Twin mounts on centreline, evenly spread
      8 - 5.00" / 127 mm 45.0 cal guns - 63.03lbs / 28.59kg shells, 150 per gun
     Quick firing guns in deck mounts, 1915 Model
     4 x Single mounts on sides, evenly spread
      12 - 2.00" / 50.8 mm 45.0 cal guns - 4.03lbs / 1.83kg shells, 250 per gun
     Breech loading guns in deck mounts, 1915 Model
     4 x Quintuple mounts on sides, evenly spread
      4 raised mounts
      Weight of broadside 1,585 lbs / 719 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   2.00" / 51 mm   200.00 ft / 60.96 m   10.00 ft / 3.05 m
   Ends:   0.50" / 13 mm   100.00 ft / 30.48 m   10.00 ft / 3.05 m
     Main Belt covers 103 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   4.00" / 102 mm   1.00" / 25 mm      4.00" / 102 mm
   2nd:   1.00" / 25 mm         -               -

   - Armoured deck - single deck:
   For and Aft decks: 1.00" / 25 mm

   - Conning towers: Forward 4.00" / 102 mm, Aft 0.00" / 0 mm

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 7,607 shp / 5,675 Kw = 20.00 kts
   Range 5,400nm at 10.00 kts
   Bunker at max displacement = 294 tons

Complement:
   173 - 225

Cost:
   £0.345 million / $1.381 million

Distribution of weights at normal displacement:
   Armament: 327 tons, 13.4 %
      - Guns: 327 tons, 13.4 %
   Armour: 414 tons, 16.9 %
      - Belts: 192 tons, 7.9 %
      - Armament: 98 tons, 4.0 %
      - Armour Deck: 108 tons, 4.4 %
      - Conning Tower: 16 tons, 0.6 %
   Machinery: 288 tons, 11.8 %
   Hull, fittings & equipment: 992 tons, 40.6 %
   Fuel, ammunition & stores: 341 tons, 14.0 %
   Miscellaneous weights: 80 tons, 3.3 %
      - On freeboard deck: 20 tons
      - Above deck: 60 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     3,311 lbs / 1,502 Kg = 12.9 x 8.0 " / 203 mm shells or 1.1 torpedoes
   Stability (Unstable if below 1.00): 1.18
   Metacentric height 2.3 ft / 0.7 m
   Roll period: 13.5 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.55
   Seaboat quality  (Average = 1.00): 1.00

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.510 / 0.516
   Length to Beam Ratio: 6.12 : 1
   'Natural speed' for length: 17.32 kts
   Power going to wave formation at top speed: 54 %
   Trim (Max stability = 0, Max steadiness = 100): 70
   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:   45.00 %,  15.00 ft / 4.57 m,  10.00 ft / 3.05 m
      - Forward deck:   30.00 %,  10.00 ft / 3.05 m,  10.00 ft / 3.05 m
      - Aft deck:   10.00 %,  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:      10.90 ft / 3.32 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 86.4 %
      - Above water (accommodation/working, high = better): 108.8 %
   Waterplane Area: 9,884 Square feet or 918 Square metres
   Displacement factor (Displacement / loading): 109 %
   Structure weight / hull surface area: 88 lbs/sq ft or 431 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.93
      - Longitudinal: 1.95
      - Overall: 1.00
   Adequate machinery, storage, compartmentation space
   Adequate accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

35t - FC
25t - LR Wireless
20t - Observation Balloon

[Desertfox]

Upgrade of the Tenryus. Adds bigger torpedoes, 2" Gatlings, and MTB capability, does lose its observation balloon capability.

Kuma, Japan Littoral Combatant laid down 1917

Displacement:
   1,397 t light; 1,459 t standard; 1,741 t normal; 1,967 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (342.64 ft / 340.00 ft) x 42.00 ft x (9.70 / 10.57 ft)
   (104.44 m / 103.63 m) x 12.80 m  x (2.96 / 3.22 m)

Armament:
      5 - 5.00" / 127 mm 45.0 cal guns - 63.03lbs / 28.59kg shells, 140 per gun
     Quick firing guns in deck and hoist mounts, 1917 Model
     3 x Single mounts on centreline ends, majority aft
      1 raised mount aft - superfiring
     2 x Single mounts on sides amidships
      6 - 2.00" / 50.8 mm 45.0 cal guns - 4.03lbs / 1.83kg shells, 200 per gun
     Quick firing guns in deck mounts, 1917 Model
     2 x Triple mounts on sides amidships
      Weight of broadside 339 lbs / 154 kg

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

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 11,328 shp / 8,451 Kw = 24.00 kts
   Range 5,900nm at 14.00 kts
   Bunker at max displacement = 508 tons

Complement:
   134 - 175

Cost:
   £0.252 million / $1.007 million

Distribution of weights at normal displacement:
   Armament: 89 tons, 5.1 %
      - Guns: 89 tons, 5.1 %
   Armour: 13 tons, 0.8 %
      - Armament: 13 tons, 0.8 %
   Machinery: 415 tons, 23.8 %
   Hull, fittings & equipment: 624 tons, 35.9 %
   Fuel, ammunition & stores: 344 tons, 19.8 %
   Miscellaneous weights: 255 tons, 14.6 %
      - Hull above water: 200 tons
      - On freeboard deck: 20 tons
      - Above deck: 35 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     1,741 lbs / 790 Kg = 27.9 x 5.0 " / 127 mm shells or 0.7 torpedoes
   Stability (Unstable if below 1.00): 1.19
   Metacentric height 1.9 ft / 0.6 m
   Roll period: 12.9 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.24
   Seaboat quality  (Average = 1.00): 1.02

Hull form characteristics:
   Hull has raised forecastle,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.440 / 0.456
   Length to Beam Ratio: 8.10 : 1
   'Natural speed' for length: 18.44 kts
   Power going to wave formation at top speed: 54 %
   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:   37.00 %,  15.00 ft / 4.57 m,  15.00 ft / 4.57 m
      - Forward deck:   30.00 %,  9.00 ft / 2.74 m,  9.00 ft / 2.74 m
      - Aft deck:   18.00 %,  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:      11.22 ft / 3.42 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 106.7 %
      - Above water (accommodation/working, high = better): 115.6 %
   Waterplane Area: 9,036 Square feet or 839 Square metres
   Displacement factor (Displacement / loading): 125 %
   Structure weight / hull surface area: 53 lbs/sq ft or 259 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.87
      - Longitudinal: 1.16
      - Overall: 0.90
   Adequate machinery, storage, compartmentation space
   Adequate accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

10t - 1908 Fire Control
25t - LR Wireless
20t - 6 x 21" Torpedo Tubes
80t - 2 x 20t MTBs
120t - Mines/Supplies/Marines