The GB/DT/1914 torpedo boat

My friend Cliff had conceived of the GB/DT/1914 as a torpedo boat, primarily, and it was flush-decked and looked anachronistic, with a single, trunked funnel. The 4in gun is mounted on the forecastle. The speed was rather modest, at 31.8 knots, which makes the Springsharp design easily to make work. The specified fuel was 250 tons, although my design is somewhat less. This is the Springsharp report:

GB/DT/1914, Great Britain Torpedo Boat laid down 1914 (Engine 1937)

Displacement:
    756 t light; 777 t standard; 900 t normal; 999 t full load

Dimensions: Length overall / water x beam x draught
    267.94 ft / 265.00 ft x 28.00 ft x 10.50 ft (normal load)
    81.67 m / 80.77 m x 8.53 m  x 3.20 m

Armament:
      1 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1914 Model
      Quick firing gun in a deck mount with hoist
      on centreline forward
    Weight of broadside 32 lbs / 15 kg
    Shells per gun, main battery: 150
    9 - 21.0" / 533.4 mm above water torpedoes

Machinery:
    Oil fired boilers, steam turbines,
    Geared drive, 2 shafts, 26,316 shp / 19,632 Kw = 31.80 kts
    Range 4,200nm at 15.00 kts
    Bunker at max displacement = 222 tons

Complement:
    81 - 106

Cost:
    £0.124 million / $0.496 million

Distribution of weights at normal displacement:
    Armament: 4 tons, 0.4 %
    Machinery: 482 tons, 53.6 %
    Hull, fittings & equipment: 270 tons, 30.0 %
    Fuel, ammunition & stores: 144 tons, 16.0 %
    Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
    Survivability (Non-critical penetrating hits needed to sink ship):
      254 lbs / 115 Kg = 7.9 x 4.0 " / 102 mm shells or 0.2 torpedoes
    Stability (Unstable if below 1.00): 1.19
    Metacentric height 1.0 ft / 0.3 m
    Roll period: 11.6 seconds
    Steadiness    - As gun platform (Average = 50 %): 52 %
            - Recoil effect (Restricted arc if above 1.00): 0.11
    Seaboat quality  (Average = 1.00): 1.04

Hull form characteristics:
    Hull has raised forecastle, rise forward of midbreak
    Block coefficient: 0.404
    Length to Beam Ratio: 9.46 : 1
    'Natural speed' for length: 16.28 kts
    Power going to wave formation at top speed: 72 %
    Trim (Max stability = 0, Max steadiness = 100): 50
    Bow angle (Positive = bow angles forward): 3.00 degrees
    Stern overhang: 2.00 ft / 0.61 m
    Freeboard (% = measuring location as a percentage of overall length):
       - Stem:        18.00 ft / 5.49 m
       - Forecastle (20 %):    16.00 ft / 4.88 m (15.00 ft / 4.57 m aft of break)
       - Mid (50 %):        14.00 ft / 4.27 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:    14.21 ft / 4.33 m

Ship space, strength and comments:
    Space    - Hull below water (magazines/engines, low = better): 176.5 %
        - Above water (accommodation/working, high = better): 24.2 %
    Waterplane Area: 4,579 Square feet or 425 Square metres
    Displacement factor (Displacement / loading): 60 %
    Structure weight / hull surface area: 25 lbs/sq ft or 124 Kg/sq metre
    Hull strength (Relative):
        - Cross-sectional: 0.43
        - Longitudinal: 3.69
        - Overall: 0.54
    Hull space for machinery, storage, compartmentation is cramped
    Room for accommodation and workspaces is extremely poor