A little coastal minesweeper with basic ASW capability. Potentially looking at one per year indefinitely.
A-1, laid down 1941
Displacement:
500 t light; 517 t standard; 551 t normal; 578 t full load
Dimensions: Length overall / water x beam x draught
167.67 ft / 161.09 ft x 26.25 ft x 9.12 ft (normal load)
51.11 m / 49.10 m x 8.00 m x 2.78 m
Armament:
1 - 4.13" / 105 mm guns in single mounts, 35.32lbs / 16.02kg shells, 1941 Model
Dual purpose gun in deck mount
on centreline forward
2 - 1.46" / 37.0 mm guns in single mounts, 1.55lbs / 0.70kg shells, 1941 Model
Anti-aircraft guns in deck mounts
on side, all amidships
2 - 0.79" / 20.0 mm guns in single mounts, 0.24lbs / 0.11kg shells, 1941 Model
Anti-aircraft guns in deck mounts
on side, all aft
Weight of broadside 39 lbs / 18 kg
Shells per gun, main battery: 250
Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm - -
2nd: 0.59" / 15 mm - -
3rd: 0.59" / 15 mm - -
Machinery:
Diesel Internal combustion motors,
Direct drive, 2 shafts, 1,400 shp / 1,044 Kw = 15.57 kts
Range 4,000nm at 10.00 kts (Bunkerage = 62 tons)
Complement:
56 - 73
Cost:
£0.165 million / $0.662 million
Distribution of weights at normal displacement:
Armament: 5 tons, 0.9 %
Armour: 3 tons, 0.5 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 3 tons, 0.5 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 37 tons, 6.7 %
Hull, fittings & equipment: 371 tons, 67.4 %
Fuel, ammunition & stores: 51 tons, 9.3 %
Miscellaneous weights: 84 tons, 15.2 %
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,610 lbs / 730 Kg = 45.6 x 4.1 " / 105 mm shells or 1.2 torpedoes
Stability (Unstable if below 1.00): 1.05
Metacentric height 0.7 ft / 0.2 m
Roll period: 12.9 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.09
Seaboat quality (Average = 1.00): 2.00
Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.500
Length to Beam Ratio: 6.14 : 1
'Natural speed' for length: 12.69 kts
Power going to wave formation at top speed: 58 %
Trim (Max stability = 0, Max steadiness = 100): 25
Bow angle (Positive = bow angles forward): 10.00 degrees
Stern overhang: 3.28 ft / 1.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 18.70 ft / 5.70 m
- Forecastle (20 %): 15.75 ft / 4.80 m
- Mid (50 %): 15.75 ft / 4.80 m (7.87 ft / 2.40 m aft of break)
- Quarterdeck (15 %): 7.87 ft / 2.40 m
- Stern: 7.87 ft / 2.40 m
- Average freeboard: 12.05 ft / 3.67 m
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 46.9 %
- Above water (accommodation/working, high = better): 110.3 %
Waterplane Area: 2,817 Square feet or 262 Square metres
Displacement factor (Displacement / loading): 276 %
Structure weight / hull surface area: 65 lbs/sq ft or 318 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.58
- Longitudinal: 14.59
- Overall: 1.97
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is adequate
Excellent seaboat, comfortable, can fire her guns in the heaviest weather