My friend Cliff's GB/FG/1913 design

My friend Cliff, in 1971, had a fondness for destroyer-like vessels armed either totally or primarily with guns. The GB/FG/1913 was a case where there were 5-4in QF guns and 2-21in TT in a twin mount. He generally specified moderate speeds, in this case 32 knots, so the designs work pretty well in Springsharp. The GB/FG/1913 is a 1,200 ton Standard displacement ship. I have shifted the parameters to achieve something close to 1,200 tons Standard and 300 tons of fuel. This is the Springsharp report for what I implemented:

GB/FG/1913, Great Britain "Frigate Gunboat" laid down 1913 (Engine 1941)

Displacement:
    1,170 t light; 1,216 t standard; 1,470 t normal; 1,673 t full load

Dimensions: Length overall / water x beam x draught
    316.15 ft / 315.00 ft x 30.00 ft x 10.00 ft (normal load)
    96.36 m / 96.01 m x 9.14 m  x 3.05 m

Armament:
      4 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1913 Model
      Quick firing guns in deck mounts with hoists
      on centreline ends, evenly spread, 2 raised mounts - superfiring
      1 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1913 Model
      Quick firing gun in a deck mount with hoist
      on centreline amidships
    Weight of broadside 160 lbs / 73 kg
    Shells per gun, main battery: 180
    2 - 21.0" / 533.4 mm above water torpedoes

Machinery:
    Oil fired boilers, steam turbines,
    Direct drive, 2 shafts, 35,762 shp / 26,679 Kw = 32.00 kts
    Range 6,750nm at 15.00 kts
    Bunker at max displacement = 457 tons

Complement:
    118 - 154

Cost:
    £0.177 million / $0.708 million

Distribution of weights at normal displacement:
    Armament: 20 tons, 1.4 %
    Machinery: 747 tons, 50.8 %
    Hull, fittings & equipment: 402 tons, 27.4 %
    Fuel, ammunition & stores: 300 tons, 20.4 %
    Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
    Survivability (Non-critical penetrating hits needed to sink ship):
      441 lbs / 200 Kg = 13.8 x 4.0 " / 102 mm shells or 0.3 torpedoes
    Stability (Unstable if below 1.00): 1.46
    Metacentric height 1.6 ft / 0.5 m
    Roll period: 10.0 seconds
    Steadiness    - As gun platform (Average = 50 %): 52 %
            - Recoil effect (Restricted arc if above 1.00): 0.37
    Seaboat quality  (Average = 1.00): 1.04

Hull form characteristics:
    Hull has rise forward of midbreak
    Block coefficient: 0.544
    Length to Beam Ratio: 10.50 : 1
    'Natural speed' for length: 17.75 kts
    Power going to wave formation at top speed: 71 %
    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:        22.00 ft / 6.71 m
       - Forecastle (20 %):    20.00 ft / 6.10 m
       - Mid (41 %):        20.00 ft / 6.10 m (12.00 ft / 3.66 m aft of break)
       - Quarterdeck (15 %):    12.00 ft / 3.66 m
       - Stern:        12.00 ft / 3.66 m
       - Average freeboard:    15.44 ft / 4.71 m

Ship space, strength and comments:
    Space    - Hull below water (magazines/engines, low = better): 174.8 %
        - Above water (accommodation/working, high = better): 131.9 %
    Waterplane Area: 6,561 Square feet or 610 Square metres
    Displacement factor (Displacement / loading): 72 %
    Structure weight / hull surface area: 28 lbs/sq ft or 137 Kg/sq metre
    Hull strength (Relative):
        - Cross-sectional: 0.45
        - Longitudinal: 2.54
        - Overall: 0.53
    Hull space for machinery, storage, compartmentation is cramped
    Room for accommodation and workspaces is excellent