GrosseTorpedoBoot-Z Class

[TacCovert4]

GTB-Z, Aztec Large Torpedo Boat laid down 1914

Displacement:
   500 t light; 520 t standard; 573 t normal; 615 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (291.79 ft / 288.71 ft) x 24.11 ft x (7.02 / 7.36 ft)
   (88.94 m / 88.00 m) x 7.35 m  x (2.14 / 2.24 m)

Armament:
      3 - 3.94" / 100 mm 50.0 cal guns - 32.30lbs / 14.65kg shells, 160 per gun
     Quick firing guns in deck mounts, 1914 Model
     3 x Single mounts on centreline ends, majority forward
      1 raised mount - superfiring
      8 - 0.31" / 8.0 mm 70.0 cal guns - 0.02lbs / 0.01kg shells, 2,000 per gun
     Machine guns in deck mounts, 1914 Model
     4 x Twin mounts on sides, evenly spread
      Weight of broadside 97 lbs / 44 kg

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 16,159 shp / 12,055 Kw = 31.00 kts
   Range 2,650nm at 12.00 kts
   Bunker at max displacement = 95 tons

Complement:
   58 - 76

Cost:
   £0.082 million / $0.330 million

Distribution of weights at normal displacement:
   Armament: 20 tons, 3.4 %
      - Guns: 20 tons, 3.4 %
   Machinery: 299 tons, 52.2 %
   Hull, fittings & equipment: 160 tons, 27.9 %
   Fuel, ammunition & stores: 73 tons, 12.8 %
   Miscellaneous weights: 21 tons, 3.7 %
      - On freeboard deck: 18 tons
      - Above deck: 3 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     158 lbs / 72 Kg = 5.2 x 3.9 " / 100 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.21
   Metacentric height 0.8 ft / 0.3 m
   Roll period: 11.1 seconds
   Steadiness   - As gun platform (Average = 50 %): 53 %
         - Recoil effect (Restricted arc if above 1.00): 0.25
   Seaboat quality  (Average = 1.00): 0.78

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.410 / 0.420
   Length to Beam Ratio: 11.97 : 1
   'Natural speed' for length: 16.99 kts
   Power going to wave formation at top speed: 65 %
   Trim (Max stability = 0, Max steadiness = 100): 68
   Bow angle (Positive = bow angles forward): 15.00 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 %,  11.48 ft / 3.50 m,  10.83 ft / 3.30 m
      - Forward deck:   30.00 %,  10.83 ft / 3.30 m,  8.86 ft / 2.70 m
      - Aft deck:   35.00 %,  8.86 ft / 2.70 m,  8.20 ft / 2.50 m
      - Quarter deck:   15.00 %,  8.20 ft / 2.50 m,  8.20 ft / 2.50 m
      - Average freeboard:      9.39 ft / 2.86 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 178.1 %
      - Above water (accommodation/working, high = better): 129.4 %
   Waterplane Area: 4,312 Square feet or 401 Square metres
   Displacement factor (Displacement / loading): 43 %
   Structure weight / hull surface area: 23 lbs/sq ft or 112 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 0.99
      - Overall: 0.54
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Poor seaboat, wet and uncomfortable, reduced performance in heavy weather



18t 2 x 3 x 533mm TT Centerline behind bridge

1t - 1908 Fire Control

2t - Additional Scopes/Searchlights and night fighting equipment

Trial Speed - 33.39kts

[TacCovert4]

And no, the Aztecs aren't speaking German.  But it's easier in my mind to comprehend the progression from MTB to GTB to DD.  I consider a DD (though this one would class as a 'small DD') to have its primary arm as its guns, while a TB has its primary arm as its torpedoes.