A new cut at the Ger/DL/1915 design study

Now that I better understand how to specify guns, the Ger/DL/1915 design study works much better. It also works better if I am ready to accept a maximum speed of 34 knots. What I had to work with is a pencil sketch and some minimal specifications:

• Guns: 4-5in/50 QF
• TT: 6-23.4in in twin mounts
• Length: 390ft
• Beam: 40ft

The forecastle is raised and there are two superfiring guns, one forward and one aft. This is the Springsharp report:

Ger/DL/1915 Design Study, Germany Destroyer Leader laid down 1915 (Engine 1927)

Displacement:
 2,218 t light; 2,291 t standard; 2,613 t normal; 2,871 t full load

Dimensions: Length overall / water x beam x draught
 391.31 ft / 390.00 ft x 40.00 ft x 13.00 ft (normal load)
 119.27 m / 118.87 m x 12.19 m  x 3.96 m

Armament:
      4 - 5.00" / 127 mm guns in single mounts, 62.00lbs / 28.12kg shells, 1915 Model
   Quick firing guns in deck mounts with hoists
   on centreline ends, evenly spread, 2 raised mounts - superfiring
 Weight of broadside 248 lbs / 112 kg
 Shells per gun, main battery: 150
 6 - 23.6" / 599.44 mm above water torpedoes

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 2 shafts, 56,373 shp / 42,054 Kw = 34.00 kts
 Range 5,400nm at 15.00 kts
 Bunker at max displacement = 579 tons

Complement:
 182 - 237

Cost:
 £0.454 million / $1.815 million

Distribution of weights at normal displacement:
 Armament: 31 tons, 1.2 %
 Machinery: 1,487 tons, 56.9 %
 Hull, fittings & equipment: 701 tons, 26.8 %
 Fuel, ammunition & stores: 395 tons, 15.1 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   669 lbs / 303 Kg = 10.7 x 5.0 " / 127 mm shells or 0.3 torpedoes
 Stability (Unstable if below 1.00): 1.57
 Metacentric height 2.7 ft / 0.8 m
 Roll period: 10.2 seconds
 Steadiness - As gun platform (Average = 50 %): 60 %
   - Recoil effect (Restricted arc if above 1.00): 0.25
 Seaboat quality  (Average = 1.00): 1.20

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.451
 Length to Beam Ratio: 9.75 : 1
 'Natural speed' for length: 19.75 kts
 Power going to wave formation at top speed: 67 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 3.00 degrees
 Stern overhang: 0.00 ft / 0.00 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  25.00 ft / 7.62 m
    - Forecastle (20 %): 22.00 ft / 6.71 m
    - Mid (50 %):  22.00 ft / 6.71 m (14.00 ft / 4.27 m aft of break)
    - Quarterdeck (15 %): 14.00 ft / 4.27 m
    - Stern:  14.00 ft / 4.27 m
    - Average freeboard: 18.24 ft / 5.56 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 192.7 %
  - Above water (accommodation/working, high = better): 122.7 %
 Waterplane Area: 9,959 Square feet or 925 Square metres
 Displacement factor (Displacement / loading): 69 %
 Structure weight / hull surface area: 35 lbs/sq ft or 170 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.45
  - Longitudinal: 2.04
  - Overall: 0.52
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is excellent
 Good seaboat, rides out heavy weather easily