Played around with springsharp for the first time, entered data from the
Colonies Class group 3 AA variant and this is what I came up with.
Grayson Islands, Grays Harbor Light Cruiser laid down 1940
Displacement:
9,172 t light; 9,600 t standard; 10,636 t normal; 11,464 t full load
Dimensions: Length overall / water x beam x draught
605.38 ft / 596.50 ft x 66.00 ft x 23.00 ft (normal load)
184.52 m / 181.81 m x 20.12 m x 7.01 m
Armament:
20 - 5.25" / 133 mm guns (6 mounts), 72.35lbs / 32.82kg shells, 1940 Model
Dual purpose guns in turrets (on barbettes)
on centreline ends, evenly spread
28 - 1.57" / 40.0 mm guns (4x7 guns), 1.95lbs / 0.89kg shells, 1940 Model
Anti-aircraft guns in turrets (on barbettes)
on side ends, evenly spread
28 - 0.79" / 20.0 mm guns (7x4 guns), 0.24lbs / 0.11kg shells, 1940 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
Weight of broadside 1,509 lbs / 684 kg
Shells per gun, main battery: 250
Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 4.00" / 102 mm 206.00 ft / 62.79 m 9.50 ft / 2.90 m
Ends: 1.50" / 38 mm 287.00 ft / 87.48 m 8.00 ft / 2.44 m
103.50 ft / 31.55 m Unarmoured ends
Upper: 1.50" / 38 mm 300.00 ft / 91.44 m 0.00 ft / 0.00 m
Main Belt covers 53 % of normal length
Main belt does not fully cover magazines and engineering spaces
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1.50" / 38 mm 1.50" / 38 mm 2.00" / 51 mm
2nd: 1.50" / 38 mm 1.50" / 38 mm 2.00" / 51 mm
Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 108,360 shp / 80,837 Kw = 34.00 kts
Range 8,500nm at 15.00 kts
Bunker at max displacement = 1,864 tons
Complement:
523 - 680
Cost:
£5.310 million / $21.241 million
Distribution of weights at normal displacement:
Armament: 189 tons, 1.8 %
Armour: 770 tons, 7.2 %
- Belts: 500 tons, 4.7 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 270 tons, 2.5 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 2,897 tons, 27.2 %
Hull, fittings & equipment: 5,316 tons, 50.0 %
Fuel, ammunition & stores: 1,464 tons, 13.8 %
Miscellaneous weights: 0 tons, 0.0 %
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
10,655 lbs / 4,833 Kg = 147.3 x 5.3 " / 133 mm shells or 1.6 torpedoes
Stability (Unstable if below 1.00): 1.10
Metacentric height 3.2 ft / 1.0 m
Roll period: 15.5 seconds
Steadiness - As gun platform (Average = 50 %): 71 %
- Recoil effect (Restricted arc if above 1.00): 0.25
Seaboat quality (Average = 1.00): 0.94
Hull form characteristics:
Hull has raised forecastle
Block coefficient: 0.411
Length to Beam Ratio: 9.04 : 1
'Natural speed' for length: 24.42 kts
Power going to wave formation at top speed: 57 %
Trim (Max stability = 0, Max steadiness = 100): 76
Bow angle (Positive = bow angles forward): 12.00 degrees
Stern overhang: 2.50 ft / 0.76 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 30.00 ft / 9.14 m
- Forecastle (33 %): 17.00 ft / 5.18 m (16.50 ft / 5.03 m aft of break)
- Mid (50 %): 15.50 ft / 4.72 m
- Quarterdeck (34 %): 16.00 ft / 4.88 m
- Stern: 17.50 ft / 5.33 m
- Average freeboard: 18.25 ft / 5.56 m
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 103.3 %
- Above water (accommodation/working, high = better): 141.1 %
Waterplane Area: 24,398 Square feet or 2,267 Square metres
Displacement factor (Displacement / loading): 132 %
Structure weight / hull surface area: 139 lbs/sq ft or 679 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.30
- Longitudinal: 1.81
- Overall: 1.34
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
Poor seaboat, wet and uncomfortable, reduced performance in heavy weather