In 1940 the obsolete cruiser HICMS Tsugaru was converted to a heavy-lift crane ship, intended to provide a mobile capability to handle large guns and other massive objects. This work carried out at the Zjiangjin Shipbuilding Navy Yard, Dairen, involved stripping away the ship's superstructure and replacing i with a huge crane rated at 165tons lifting capacity. To ensure stability, Tsugaru's hull was fitted with ballast tanks and side blisters. She also retained new diesel engines.
HICMS Crane Ship - 1
(ex HICMS Tsugaru)
Displacement:
6.260 t light; 6.423 t standard; 7.984 t normal; 9.233 t full load
Dimensions:
Length overall / water x beam x draught
410,00 ft / 410,00 ft x 55,00 ft (Bulges 64,91 ft) x 21,00 ft (normal load)
124,97 m / 124,97 m x 16,76 m (Bulges 19,79 m) x 6,40 m
Armament:
8 - 1,57" / 40,0 mm guns (4x2 guns), 1,95lbs / 0,88kg shells, 1940 Model
Anti-aircraft guns in deck mounts with hoists
on side ends, evenly spread, all raised mounts - superfiring
Weight of broadside 16 lbs / 7 kg
Shells per gun, main battery: 400
Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 2,00" / 51 mm 246,00 ft / 74,98 m 8,89 ft / 2,71 m
Ends: Unarmoured
Main Belt covers 92% of normal length
- Torpedo Bulkhead and Bulges:
11,8" / 300 mm 245,90 ft / 74,95 m 18,47 ft / 5,63 m
Machinery:
Diesel Internal combustion motors,
Geared drive, 3 shafts, 6.018 shp / 4.489 Kw = 16,00 kts
Range 40.000nm at 10,00 kts
Bunker at max displacement = 2.810 tons
Complement:
422 - 549
Cost:
£0,243 million / $0,973 million
Distribution of weights at normal displacement:
Armament: 2 tons, 0,0%
Armour: 2.175 tons, 27,2%
- Belts: 190 tons, 2,4%
- Torpedo bulkhead: 1.985 tons, 24,9%
- Armament: 0 tons, 0,0%
- Armour Deck: 0 tons, 0,0%
- Conning Tower: 0 tons, 0,0%
Machinery: 161 tons, 2,0%
Hull, fittings & equipment: 1.922 tons, 24,1%
Fuel, ammunition & stores: 1.724 tons, 21,6%
Miscellaneous weights: 2.000 tons, 25,0%
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
22.983 lbs / 10.425 Kg = 11.769,4 x 1,6 " / 40 mm shells or 8,5 torpedoes
Stability (Unstable if below 1.00): 1,30
Metacentric height 3,3 ft / 1,0 m
Roll period: 15,1 seconds
Steadiness - As gun platform (Average = 50 %): 79 %
- Recoil effect (Restricted arc if above 1.00): 0,00
Seaboat quality (Average = 1.00): 1,97
Hull form characteristics:
Hull has a flush deck
Block coefficient: 0,500
Length to Beam Ratio: 6,32 : 1
'Natural speed' for length: 20,25 kts
Power going to wave formation at top speed: 36 %
Trim (Max stability = 0, Max steadiness = 100): 40
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: 20,34 ft / 6,20 m
- Forecastle (20%): 15,75 ft / 4,80 m
- Mid (50%): 14,44 ft / 4,40 m
- Quarterdeck (20%): 14,44 ft / 4,40 m
- Stern: 14,44 ft / 4,40 m
- Average freeboard: 15,26 ft / 4,65 m
Ship tends to be wet forward
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 55,7%
- Above water (accommodation/working, high = better): 100,1%
Waterplane Area: 15.025 Square feet or 1.396 Square metres
Displacement factor (Displacement / loading): 177%
Structure weight / hull surface area: 78 lbs/sq ft or 379 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0,95
- Longitudinal: 1,58
- Overall: 1,00
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
Comments:
real range: 10.780nm = 810tons
2000 tons ballast tanks simed with bunkerage
Breakdown of Miscellaneous Weight:
- 500 tons heavy lift crane above deck (lifting capacity ~ 165tons)
- 500 tons for winches and handling gear and cranes on deck
- 500 tons storage under deck
- 500 tons for powerplant, fresh water generator etc.