Aichwaldsee, German Minesweeper laid down 1950
Displacement: 463 t light; 477 t standard; 535 t normal; 582 t full load
Dimensions: Length overall / water x beam x draught
184.40 ft / 180.45 ft x 30.51 ft x 8.20 ft (normal load) [56.21 m / 55.00 m x 9.30 m x 2.50 m]
Armament:
1 - 4.13" / 105 mm guns in single mounts, 35.32lbs / 16.02kg shells, 1950 Model Anti-aircraft gun in deck mount on centerline forward
2 - 1.46" / 37.0 mm guns (1x2 guns), 1.55lbs / 0.70kg shells, 1950 Model Anti-aircraft guns in deck mount on centerline aft, all raised guns - superfiring
4 - 0.79" / 20.0 mm guns (2x2 guns), 0.24lbs / 0.11kg shells, 1950 Model Anti-aircraft guns in deck mounts on centerline, all amidships, all raised mounts - superfiring
Weight of broadside 39 lbs / 18 kg
Shells per gun, main battery: 150
Armor:
Gun armor: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.59" / 15 mm 0.39" / 10 mm -
2nd: 0.39" / 10 mm 0.39" / 10 mm -
Conning tower: 0.98" / 25 mm
Machinery:
Diesel Internal combustion motors, Geared drive, 2 shafts, 1,414 shp / 1,054 Kw = 16.00 kts
Range 5,000nm at 12.00 kts
Bunker at max displacement = 105 tons
Complement: 55 - 72
Cost: £0.196 million / $0.784 million
Distribution of weights at normal displacement:
Armament: 5 tons, 0.9 %
Armor: 3 tons, 0.6 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 2 tons, 0.4 %
- Armor Deck: 0 tons, 0.0 %
- Conning Tower: 1 tons, 0.3 %
Machinery: 34 tons, 6.3 %
Hull, fittings & equipment: 320 tons, 59.9 %
Fuel, ammunition & stores: 73 tons, 13.6 %
Miscellaneous weights: 100 tons, 18.7 %
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship): 1,551 lbs / 704 Kg = 43.9 x 4.1 " / 105 mm shells or 1.2 torpedoes
Stability (Unstable if below 1.00): 1.10
Metacentric height 1.0 ft / 0.3 m
Roll period: 12.8 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.06
Seaboat quality (Average = 1.00): 1.55
Hull form characteristics:
Hull has a flush deck
Block coefficient: 0.415
Length to Beam Ratio: 5.91: 1
'Natural speed' for length: 13.43 kts
Power going to wave formation at top speed: 53 %
Trim (Max stability = 0, Max steadiness = 100): 45
Bow angle (Positive = bow angles forward): 15.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 14.76 ft / 4.50 m
- Forecastle (20 %): 9.42 ft / 2.87 m
- Mid (50 %): 9.42 ft / 2.87 m
- Quarterdeck (25 %): 9.42 ft / 2.87 m
- Stern: 9.42 ft / 2.87 m
- Average freeboard: 9.84 ft / 3.00 m
Ship tends to be wet forward
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 49.1 %
- Above water (accommodation/working, high = better): 111.6 %
Waterplane Area: 3,421 Square feet or 318 Square meters
Displacement factor (Displacement / loading): 254 %
Structure weight / hull surface area: 61 lbs/sq ft or 298 Kg/sq meter
Hull strength (Relative):
- Cross-sectional: 1.48
- Longitudinal: 5.09
- Overall: 1.67
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is adequate
Ship has slow, easy roll, a good, steady gun platform
Excellent seaboat, comfortable, can fire her guns in the heaviest weather
Breakdown of miscellaneous weight:
Radar and electronics suite: 15 tons
Degaussing equipment: 10 tons
Paravanes and other minesweeping equipment/gear: 75 tons
Aichwaldsee – Laid down 1 January 1950; Launched 9 March 1950