The Ger/DD/1914 design

I would say that the empirical formula used by Springsharp for calculating power for a destroyer is not working well. When I made my sketch design in 1971, I consulted Jane's Fighting Ships for 1914 and 1918 to determine reasonable power for the modest speed of 32 knots, and it was far less than what Springsharp is saying. That has caused me to have to use very lightweight machinery to make the design work. This is the first time that I have been able to implement this with the right dimensions and displacement, so that is an advance, at least. This is the original specification:

Ger/DD/1914    2-4in QF, 6-21in TT  20 mines
 265ft x 27ft x 9.5ft   900 tons Standard
 200 tons oil fuel   18,000 SHP=32 knots
 Cost: £81,000

This is the Springsharp report that I actually implemented:

Ger/DD/1914, Germany Destroyer laid down 1914 (Engine 1945)

Displacement:
 885 t light; 912 t standard; 1,050 t normal; 1,161 t full load

Dimensions: Length overall / water x beam x draught
 269.26 ft / 265.00 ft x 27.00 ft x 9.50 ft (normal load)
 82.07 m / 80.77 m x 8.23 m  x 2.90 m

Armament:
      2 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1914 Model
   Quick firing guns in deck mounts with hoists
   on centreline ends, evenly spread
 Weight of broadside 64 lbs / 29 kg
 Shells per gun, main battery: 150
 6 - 21.0" / 533.4 mm above water torpedoes

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 2 shafts, 32,630 shp / 24,342 Kw = 32.00 kts
 Range 4,500nm at 15.00 kts
 Bunker at max displacement = 249 tons

Complement:
 91 - 119

Cost:
 £0.147 million / $0.587 million

Distribution of weights at normal displacement:
 Armament: 8 tons, 0.8 %
 Machinery: 555 tons, 52.8 %
 Hull, fittings & equipment: 303 tons, 28.8 %
 Fuel, ammunition & stores: 165 tons, 15.7 %
 Miscellaneous weights: 20 tons, 1.9 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   284 lbs / 129 Kg = 8.9 x 4.0 " / 102 mm shells or 0.2 torpedoes
 Stability (Unstable if below 1.00): 1.26
 Metacentric height 1.1 ft / 0.3 m
 Roll period: 11.0 seconds
 Steadiness - As gun platform (Average = 50 %): 51 %
   - Recoil effect (Restricted arc if above 1.00): 0.24
 Seaboat quality  (Average = 1.00): 1.03

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.541
 Length to Beam Ratio: 9.81 : 1
 'Natural speed' for length: 16.28 kts
 Power going to wave formation at top speed: 75 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): 3.00 degrees
 Stern overhang: 3.00 ft / 0.91 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  24.00 ft / 7.32 m
    - Forecastle (20 %): 22.00 ft / 6.71 m
    - Mid (25 %):  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: 16.16 ft / 4.93 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 178.5 %
  - Above water (accommodation/working, high = better): 63.9 %
 Waterplane Area: 4,950 Square feet or 460 Square metres
 Displacement factor (Displacement / loading): 61 %
 Structure weight / hull surface area: 24 lbs/sq ft or 116 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.40
  - Longitudinal: 5.04
  - Overall: 0.52
 Hull space for machinery, storage, compartmentation is cramped
 Room for accommodation and workspaces is cramped