WesWorld

Quoted

Modified Struma, Bulgarian Minesweeper laid down 1936

Displacement:
494 t light; 511 t standard; 579 t normal; 634 t full load

Dimensions: Length overall / water x beam x draught
197.75 ft / 194.00 ft x 27.00 ft x 9.00 ft (normal load)
60.27 m / 59.13 m x 8.23 m x 2.74 m

Armament:
2 - 3.46" / 88.0 mm guns (1x2 guns), 20.79lbs / 9.43kg shells, 1936 Model
Dual purpose guns in deck mount
on centreline forward
2 - 1.46" / 37.0 mm guns (1x2 guns), 1.55lbs / 0.70kg shells, 1936 Model
Anti-aircraft guns in deck mount
on centreline aft, all raised guns - superfiring
2 - 0.79" / 20.0 mm guns (1x2 guns), 0.24lbs / 0.11kg shells, 1936 Model
Anti-aircraft guns in deck mount
on centreline forward, all raised guns - superfiring
4 - 0.50" / 12.7 mm guns (2x2 guns), 0.06lbs / 0.03kg shells, 1936 Model
Machine guns in deck mounts
on side, all amidships, all raised mounts - superfiring
Weight of broadside 45 lbs / 21 kg
Shells per gun, main battery: 200

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.79" / 20 mm 0.39" / 10 mm -
2nd: 0.39" / 10 mm - -

- Conning tower: 0.98" / 25 mm

Machinery:
Diesel Internal combustion motors,
Geared drive, 2 shafts, 2,828 shp / 2,110 Kw = 19.00 kts
Range 5,000nm at 12.00 kts
Bunker at max displacement = 122 tons

Complement:
58 - 76

Cost:
£0.175 million / $0.700 million

Distribution of weights at normal displacement:
Armament: 6 tons, 1.0 %
Armour: 4 tons, 0.7 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 2 tons, 0.4 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 1 tons, 0.3 %
Machinery: 79 tons, 13.7 %
Hull, fittings & equipment: 225 tons, 38.9 %
Fuel, ammunition & stores: 85 tons, 14.7 %
Miscellaneous weights: 180 tons, 31.1 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
967 lbs / 439 Kg = 46.5 x 3.5 " / 88 mm shells or 0.6 torpedoes
Stability (Unstable if below 1.00): 1.08
Metacentric height 0.8 ft / 0.2 m
Roll period: 12.6 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.09
Seaboat quality (Average = 1.00): 1.73

Hull form characteristics:
Hull has a flush deck
Block coefficient: 0.430
Length to Beam Ratio: 7.19 : 1
'Natural speed' for length: 13.93 kts
Power going to wave formation at top speed: 58 %
Trim (Max stability = 0, Max steadiness = 100): 29
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: 14.00 ft / 4.27 m
- Forecastle (20 %): 11.00 ft / 3.35 m
- Mid (50 %): 11.00 ft / 3.35 m
- Quarterdeck (15 %): 11.00 ft / 3.35 m
- Stern: 11.00 ft / 3.35 m
- Average freeboard: 11.24 ft / 3.43 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 86.6 %
- Above water (accommodation/working, high = better): 118.8 %
Waterplane Area: 3,289 Square feet or 306 Square metres
Displacement factor (Displacement / loading): 149 %
Structure weight / hull surface area: 36 lbs/sq ft or 177 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.85
- Longitudinal: 4.62
- Overall: 1.01
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