I had to do some really bizarre things to get the GB/PG/1915 to work in Springsharp

My friend Cliff had this concept for a 36-knot fast gunboat that was really a destroyer without torpedoes. The length he set was 275 ft and he hoped it could be done on 900 tons. I am guessing that the armament was something like 3-4.7in QF guns. It had to be better than 3-4in guns. The 36 knot speed created big problems in Springsharp. I did the usual things to make it work, even though they produce a strange ships (too deep a draft for a destroyer of this size). The existence proof that this design should work is the British S-class destroyers, some of which made 40 knots on trials, and were specified to be 36-knot ships. This is the Springsharp report:

GB/PG/1915, Great Britain Fast Gunboat laid down 1915 (Engine 1932)

Displacement:
 1,092 t light; 1,115 t standard; 1,171 t normal; 1,216 t full load

Dimensions: Length overall / water x beam x draught
 275.66 ft / 275.00 ft x 27.00 ft x 16.00 ft (normal load)
 84.02 m / 83.82 m x 8.23 m  x 4.88 m

Armament:
      3 - 4.70" / 119 mm guns in single mounts, 51.91lbs / 23.55kg shells, 1915 Model
   Quick firing guns in deck mounts with hoists
   on centreline ends, majority forward, all raised mounts - superfiring
 Weight of broadside 156 lbs / 71 kg
 Shells per gun, main battery: 0

Machinery:
 Oil fired boilers, steam turbines, 
 Geared drive, 2 shafts, 50,061 shp / 37,346 Kw = 36.00 kts
 Range 3,500nm at 10.00 kts
 Bunker at max displacement = 101 tons

Complement:
 99 - 130

Cost:
 £0.222 million / $0.887 million

Distribution of weights at normal displacement:
 Armament: 19 tons, 1.7 %
 Machinery: 699 tons, 59.7 %
 Hull, fittings & equipment: 373 tons, 31.9 %
 Fuel, ammunition & stores: 79 tons, 6.8 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   189 lbs / 86 Kg = 3.6 x 4.7 " / 119 mm shells or 0.2 torpedoes
 Stability (Unstable if below 1.00): 1.20
 Metacentric height 1.0 ft / 0.3 m
 Roll period: 11.4 seconds
 Steadiness - As gun platform (Average = 50 %): 55 %
   - Recoil effect (Restricted arc if above 1.00): 0.69
 Seaboat quality  (Average = 1.00): 1.02

Hull form characteristics:
 Hull has rise forward of midbreak
 Block coefficient: 0.345
 Length to Beam Ratio: 10.19 : 1
 'Natural speed' for length: 16.58 kts
 Power going to wave formation at top speed: 72 %
 Trim (Max stability = 0, Max steadiness = 100): 54
 Bow angle (Positive = bow angles forward): 2.00 degrees
 Stern overhang: 0.00 ft / 0.00 m
 Freeboard (% = measuring location as a percentage of overall length):
    - Stem:  19.00 ft / 5.79 m
    - Forecastle (36 %): 18.00 ft / 5.49 m
    - Mid (36 %):  18.00 ft / 5.49 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: 14.94 ft / 4.55 m

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 204.0 %
  - Above water (accommodation/working, high = better): 112.9 %
 Waterplane Area: 4,512 Square feet or 419 Square metres
 Displacement factor (Displacement / loading): 38 %
 Structure weight / hull surface area: 30 lbs/sq ft or 145 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.39
  - Longitudinal: 5.38
  - Overall: 0.50
 Hull space for machinery, storage, compartmentation is extremely poor
 Room for accommodation and workspaces is adequate