W-1, Japan Minesweeper laid down 1942
Displacement:
581 t light; 622 t standard; 666 t normal; 701 t full load
Dimensions: Length overall / water x beam x draught
234.00 ft / 234.00 ft x 25.75 ft x 8.60 ft (normal load)
71.32 m / 71.32 m x 7.85 m x 2.62 m
Armament:
3 - 5.00" / 127 mm guns in single mounts, 55.12lbs / 25.00kg shells, 1942 Model
Dual purpose guns in deck mounts with hoists
on centreline ends, majority aft
3 - 0.98" / 25.0 mm guns (1x3 guns), 0.57lbs / 0.26kg shells, 1942 Model
Anti-aircraft guns in deck mount
on side amidships
Weight of broadside 167 lbs / 76 kg
Shells per gun, main battery: 300
Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1.00" / 25 mm 1.00" / 25 mm -
Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 3,436 shp / 2,563 Kw = 20.00 kts
Range 2,100nm at 14.00 kts
Bunker at max displacement = 79 tons
Complement:
65 - 85
Cost:
£0.336 million / $1.342 million
Distribution of weights at normal displacement:
Armament: 24 tons, 3.5%
Armour: 12 tons, 1.8%
- Belts: 0 tons, 0.0%
- Torpedo bulkhead: 0 tons, 0.0%
- Armament: 12 tons, 1.8%
- Armour Deck: 0 tons, 0.0%
- Conning Tower: 0 tons, 0.0%
Machinery: 90 tons, 13.5%
Hull, fittings & equipment: 320 tons, 48.1%
Fuel, ammunition & stores: 85 tons, 12.8%
Miscellaneous weights: 135 tons, 20.3%
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
963 lbs / 437 Kg = 15.4 x 5.0 " / 127 mm shells or 0.5 torpedoes
Stability (Unstable if below 1.00): 1.05
Metacentric height 0.7 ft / 0.2 m
Roll period: 12.7 seconds
Steadiness - As gun platform (Average = 50 %): 51 %
- Recoil effect (Restricted arc if above 1.00): 0.69
Seaboat quality (Average = 1.00): 1.64
Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.450
Length to Beam Ratio: 9.09 : 1
'Natural speed' for length: 15.30 kts
Power going to wave formation at top speed: 53 %
Trim (Max stability = 0, Max steadiness = 100): 31
Bow angle (Positive = bow angles forward): 0.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 16.00 ft / 4.88 m
- Forecastle (20%): 14.00 ft / 4.27 m
- Mid (50%): 14.00 ft / 4.27 m (7.00 ft / 2.13 m aft of break)
- Quarterdeck (15%): 7.00 ft / 2.13 m
- Stern: 7.00 ft / 2.13 m
- Average freeboard: 10.66 ft / 3.25 m
Ship tends to be wet forward
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 95.3%
- Above water (accommodation/working, high = better): 115.2%
Waterplane Area: 3,843 Square feet or 357 Square metres
Displacement factor (Displacement / loading): 129%
Structure weight / hull surface area: 44 lbs/sq ft or 217 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.88
- Longitudinal: 3.23
- Overall: 1.00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is adequate
Excellent seaboat, comfortable, can fire her guns in the heaviest weather
35 tons for electronics.
40 tons for depth charges and depth charge projector.
60 tons for mine sweeping equipment.