My Ger/DD/1915 destroyer design was predicated on very lightweight machinery. The displacement was to be 800 tons and the dimensions were 240ft x 26ft. The armament was 2-4in QF guns, 4-21in TT, and 20 mines. The speed was not specified, but the best that I could do with Springsharp was about 32 knots. This is a comparison between the original concept and the Springsharp design:
Original Springsharp
Armament: 20 tons 8 tons
Machinery: 444 tons 410 tons
Hull: 272 tons 275 tons
Misc: 64 tons 88 tons
Oil Fuel: 200 tons 119 tons
Feedwater: 50 tons
This is the Springsharp report:
Ger/DD/1915, Germany Destroyer laid down 1915 (Engine 1950)
Displacement:
712 t light; 734 t standard; 800 t normal; 853 t full load
Dimensions: Length overall / water x beam x draught
243.77 ft / 240.00 ft x 26.00 ft x 11.00 ft (normal load)
74.30 m / 73.15 m x 7.92 m x 3.35 m
Armament:
2 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1915 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
4 - 21.0" / 533.4 mm above water torpedoes
Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 27,020 shp / 20,157 Kw = 32.00 kts
Range 2,600nm at 15.00 kts
Bunker at max displacement = 119 tons
Complement:
74 - 97
Cost:
£0.129 million / $0.518 million
Distribution of weights at normal displacement:
Armament: 8 tons, 1.0 %
Machinery: 410 tons, 51.2 %
Hull, fittings & equipment: 275 tons, 34.3 %
Fuel, ammunition & stores: 88 tons, 11.0 %
Miscellaneous weights: 20 tons, 2.5 %
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
229 lbs / 104 Kg = 7.2 x 4.0 " / 102 mm shells or 0.2 torpedoes
Stability (Unstable if below 1.00): 1.18
Metacentric height 0.9 ft / 0.3 m
Roll period: 11.5 seconds
Steadiness - As gun platform (Average = 50 %): 52 %
- Recoil effect (Restricted arc if above 1.00): 0.28
Seaboat quality (Average = 1.00): 1.04
Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.408
Length to Beam Ratio: 9.23 : 1
'Natural speed' for length: 15.49 kts
Power going to wave formation at top speed: 74 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 2.00 degrees
Stern overhang: 3.00 ft / 0.91 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 22.00 ft / 6.71 m
- Forecastle (20 %): 21.00 ft / 6.40 m
- Mid (22 %): 21.00 ft / 6.40 m (13.00 ft / 3.96 m aft of break)
- Quarterdeck (15 %): 13.00 ft / 3.96 m
- Stern: 13.00 ft / 3.96 m
- Average freeboard: 14.84 ft / 4.52 m
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 175.7 %
- Above water (accommodation/working, high = better): 73.5 %
Waterplane Area: 3,859 Square feet or 359 Square metres
Displacement factor (Displacement / loading): 58 %
Structure weight / hull surface area: 27 lbs/sq ft or 130 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.44
- Longitudinal: 6.49
- Overall: 0.58
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is cramped
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