ASW Cruisers

[Desertfox]

Order of Battle

Chihaya class (1902)
Chihaya
Unnamed
Unnamed
Unnamed

[Desertfox]

Converted and reclassified in 1920

Chihaya class, Japan Gunboat laid down 1902

Displacement:
   1,126 t light; 1,168 t standard; 1,282 t normal; 1,374 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (301.94 ft / 300.00 ft) x 34.00 ft x (10.00 / 10.50 ft)
   (92.03 m / 91.44 m) x 10.36 m  x (3.05 / 3.20 m)

Armament:
      2 - 5.00" / 127 mm 45.0 cal guns - 63.03lbs / 28.59kg shells, 170 per gun
     Quick firing guns in deck mounts, 1902 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, 1910 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:   0.50" / 13 mm         -               -

   - Conning towers: Forward 0.50" / 13 mm, Aft 0.00" / 0 mm

Machinery:
   Oil fired boilers, complex reciprocating steam engines,
   Direct drive, 2 shafts, 4,715 ihp / 3,517 Kw = 20.00 kts
   Range 4,000nm at 10.00 kts
   Bunker at max displacement = 206 tons

Complement:
   106 - 139

Cost:
   £0.128 million / $0.511 million

Distribution of weights at normal displacement:
   Armament: 31 tons, 2.4 %
      - Guns: 31 tons, 2.4 %
   Armour: 4 tons, 0.3 %
      - Armament: 3 tons, 0.2 %
      - Conning Tower: 1 tons, 0.1 %
   Machinery: 569 tons, 44.3 %
   Hull, fittings & equipment: 376 tons, 29.3 %
   Fuel, ammunition & stores: 156 tons, 12.2 %
   Miscellaneous weights: 148 tons, 11.5 %
      - Hull below water: 37 tons
      - On freeboard deck: 90 tons
      - Above deck: 21 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     689 lbs / 312 Kg = 11.0 x 5.0 " / 127 mm shells or 0.4 torpedoes
   Stability (Unstable if below 1.00): 1.51
   Metacentric height 2.0 ft / 0.6 m
   Roll period: 10.1 seconds
   Steadiness   - As gun platform (Average = 50 %): 75 %
         - Recoil effect (Restricted arc if above 1.00): 0.09
   Seaboat quality  (Average = 1.00): 1.48

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.440 / 0.449
   Length to Beam Ratio: 8.82 : 1
   'Natural speed' for length: 17.32 kts
   Power going to wave formation at top speed: 47 %
   Trim (Max stability = 0, Max steadiness = 100): 51
   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 %,  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:   25.00 %,  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:      9.24 ft / 2.82 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 153.5 %
      - Above water (accommodation/working, high = better): 104.4 %
   Waterplane Area: 6,454 Square feet or 600 Square metres
   Displacement factor (Displacement / loading): 84 %
   Structure weight / hull surface area: 41 lbs/sq ft or 201 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.88
      - Longitudinal: 1.08
      - Overall: 0.90
   Caution: Hull subject to strain in open-sea
   Cramped 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

3t - FC
55t - Auxilary sail rigging
65t - ASW Gear
25t - Wireless