Minesweepers

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T1, Japan Minesweeper laid down 1898 Virtuous Class

Displacement:
   178 t light; 185 t standard; 192 t normal; 197 t full load

Dimensions: Length overall / water x beam x draught
   131.23 ft / 131.23 ft x 17.72 ft x 7.22 ft (normal load)
   40.00 m / 40.00 m x 5.40 m  x 2.20 m

Armament:
      2 - 2.99" / 76.0 mm guns in single mounts, 13.39lbs / 6.08kg shells, 1898 Model
     Breech loading guns in deck mounts with hoists
     on side, evenly spread
   Weight of broadside 27 lbs / 12 kg
   Shells per gun, main battery: 200

Machinery:
   Coal fired boilers, complex reciprocating steam engines,
   Direct drive, 1 shaft, 484 ihp / 361 Kw = 14.00 kts
   Range 1,500nm at 6.00 kts
   Bunker at max displacement = 13 tons (100% coal)

Complement:
   25 - 33

Cost:
   £0.019 million / $0.074 million

Distribution of weights at normal displacement:
   Armament: 3 tons, 1.7 %
   Machinery: 68 tons, 35.6 %
   Hull, fittings & equipment: 66 tons, 34.5 %
   Fuel, ammunition & stores: 14 tons, 7.2 %
   Miscellaneous weights: 40 tons, 20.9 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     87 lbs / 40 Kg = 6.5 x 3.0 " / 76 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.10
   Metacentric height 0.4 ft / 0.1 m
   Roll period: 11.1 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.24
   Seaboat quality  (Average = 1.00): 1.26

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0.400
   Length to Beam Ratio: 7.41 : 1
   'Natural speed' for length: 11.46 kts
   Power going to wave formation at top speed: 50 %
   Trim (Max stability = 0, Max steadiness = 100): 40
   Bow angle (Positive = bow angles forward): 0.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      8.20 ft / 2.50 m
      - Forecastle (20 %):   4.92 ft / 1.50 m
      - Mid (50 %):      4.92 ft / 1.50 m
      - Quarterdeck (15 %):   4.92 ft / 1.50 m
      - Stern:      4.92 ft / 1.50 m
      - Average freeboard:   5.18 ft / 1.58 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 151.6 %
      - Above water (accommodation/working, high = better): 50.7 %
   Waterplane Area: 1,353 Square feet or 126 Square metres
   Displacement factor (Displacement / loading): 86 %
   Structure weight / hull surface area: 28 lbs/sq ft or 138 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.93
      - Longitudinal: 2.44
      - Overall: 1.03
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is cramped
   Good seaboat, rides out heavy weather easily

Ships:
T1 Desheng (Virtuous Victory) (6)