DD-J Class

[TacCovert4]

J-Class, Aztec Destroyer laid down 1926

Displacement:
   2,000 t light; 2,084 t standard; 2,485 t normal; 2,805 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (400.27 ft / 393.70 ft) x 38.06 ft x (10.75 / 11.83 ft)
   (122.00 m / 120.00 m) x 11.60 m  x (3.28 / 3.61 m)

Armament:
      8 - 3.94" / 100 mm 50.0 cal guns - 32.30lbs / 14.65kg shells, 200 per gun
     Quick firing guns in deck mounts, 1926 Model
     4 x Twin mounts on centreline ends, evenly spread
      2 raised mounts - superfiring
      12 - 1.18" / 30.0 mm 50.0 cal guns - 0.87lbs / 0.40kg shells, 1,000 per gun
     Quick firing guns in deck and hoist mounts, 1926 Model
     6 x Twin mounts on sides, evenly spread
      Weight of broadside 269 lbs / 122 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.06" / 27 mm   0.87" / 22 mm            -
   2nd:         -            -         0.79" / 20 mm

   - Conning towers: Forward 1.06" / 27 mm, Aft 0.00" / 0 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 43,946 shp / 32,784 Kw = 32.00 kts
   Range 8,000nm at 14.00 kts
   Bunker at max displacement = 721 tons

Complement:
   175 - 228

Cost:
   £0.908 million / $3.632 million

Distribution of weights at normal displacement:
   Armament: 47 tons, 1.9 %
      - Guns: 47 tons, 1.9 %
   Armour: 26 tons, 1.0 %
      - Armament: 22 tons, 0.9 %
      - Conning Tower: 4 tons, 0.2 %
   Machinery: 1,265 tons, 50.9 %
   Hull, fittings & equipment: 582 tons, 23.4 %
   Fuel, ammunition & stores: 485 tons, 19.5 %
   Miscellaneous weights: 80 tons, 3.2 %
      - Hull below water: 15 tons
      - Hull above water: 6 tons
      - On freeboard deck: 54 tons
      - Above deck: 5 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     774 lbs / 351 Kg = 25.4 x 3.9 " / 100 mm shells or 0.4 torpedoes
   Stability (Unstable if below 1.00): 1.39
   Metacentric height 2.1 ft / 0.6 m
   Roll period: 11.1 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.19
   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): 0.540 / 0.554
   Length to Beam Ratio: 10.34 : 1
   'Natural speed' for length: 19.84 kts
   Power going to wave formation at top speed: 66 %
   Trim (Max stability = 0, Max steadiness = 100): 66
   Bow angle (Positive = bow angles forward): 20.00 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 %,  18.04 ft / 5.50 m,  18.04 ft / 5.50 m
      - Forward deck:   30.00 %,  18.04 ft / 5.50 m,  14.76 ft / 4.50 m
      - Aft deck:   35.00 %,  14.76 ft / 4.50 m,  14.76 ft / 4.50 m
      - Quarter deck:   15.00 %,  14.76 ft / 4.50 m,  14.76 ft / 4.50 m
      - Average freeboard:      15.91 ft / 4.85 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 172.1 %
      - Above water (accommodation/working, high = better): 175.0 %
   Waterplane Area: 10,359 Square feet or 962 Square metres
   Displacement factor (Displacement / loading): 81 %
   Structure weight / hull surface area: 33 lbs/sq ft or 161 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.25
      - Overall: 0.55
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

11t - 1918 FC
32t - 2x4x21in HW TT Centerline
15t - Enhanced Hydrophones 1915
2t - 2 x DC Thrower
20t - 100 x 195kg DC