In line with some of the thoughts percolating in the StormEx thread, I've put together a proposal for a small civil response vessel for the Philippine Navy; while useful perhaps in disaster relief, I envision something that could be useful in supporting the civil authority in a variety of missions.
Comments welcome.
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TBD, Philippine Civil Support Ship laid down 1945
Displacement: 410 t light; 424 t standard; 686 t normal; 896 t full load
Dimensions: Length overall / water x beam x draught
150.22 ft / 144.36 ft x 24.61 ft x 9.02 ft (normal load) [45.79 m / 44.00 m x 7.50 m x 2.75 m]
Armament:
1 - 0.98" / 25.0 mm guns in single mounts, 0.48lbs / 0.22kg shells, 1945 Model Anti-aircraft gun in deck mount on centreline forward
2 - 0.50" / 12.7 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1945 Model Machine guns in deck mounts on side, evenly spread, all raised mounts
Weight of broadside 1 lbs / 0 kg
Shells per gun, main battery: 300
Armour:
Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.39" / 10 mm 0.39" / 10 mm -
Conning tower: 0.39" / 10 mm
Machinery:
Diesel Internal combustion motors, Geared drive, 2 shafts, 2,161 shp / 1,612 Kw = 16.00 kts
Range 10,000nm at 14.00 kts
Bunker at max displacement = 472 tons
Complement: 66 - 87
Cost: £0.152 million / $0.609 million
Distribution of weights at normal displacement:
Armament: 0 tons, 0.0 %
Armour: 1 tons, 0.1 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 0 tons, 0.0 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 1 tons, 0.1 %
Machinery: 55 tons, 8.0 %
Hull, fittings & equipment: 234 tons, 34.2 %
Fuel, ammunition & stores: 276 tons, 40.2 %
Miscellaneous weights: 120 tons, 17.5 %
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship): 2,094 lbs / 950 Kg = 4,392.9 x 1.0 " / 25 mm shells or 1.3 torpedoes
Stability (Unstable if below 1.00): 1.10
Metacentric height 0.7 ft / 0.2 m
Roll period: 12.1 seconds
Steadiness - As gun platform (Average = 50 %): 72 %
- Recoil effect (Restricted arc if above 1.00): 0.00
Seaboat quality (Average = 1.00): 2.00
Hull form characteristics:
Hull has raised quarterdeck
Block coefficient: 0.749
Length to Beam Ratio: 5.87 : 1
'Natural speed' for length: 12.01 kts
Power going to wave formation at top speed: 69 %
Trim (Max stability = 0, Max steadiness = 100): 36
Bow angle (Positive = bow angles forward): 18.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 18.04 ft / 5.50 m
- Forecastle (20 %): 15.58 ft / 4.75 m
- Mid (50 %): 13.12 ft / 4.00 m
- Quarterdeck (15 %): 15.58 ft / 4.75 m (13.12 ft / 4.00 m before break)
- Stern: 15.58 ft / 4.75 m
- Average freeboard: 14.55 ft / 4.44 m
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 46.2 %
- Above water (accommodation/working, high = better): 117.5 %
Waterplane Area: 2,973 Square feet or 276 Square metres
Displacement factor (Displacement / loading): 297 %
Structure weight / hull surface area: 34 lbs/sq ft or 168 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.84
- Longitudinal: 16.91
- Overall: 1.14
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
Cargo simmed as bunkers - Actual radius 2,200 nm at 14 knots with BAM 109 tons.
Cargo represents 80 tons POL storage for distribution, 80 tons dry stores for distribution, 40 tons medical supplies for use or distribution, 20 tons fresh water in
tanks with pumps
Breakdown of miscellaneous weight:
Accommodation for disaster response team - 30 tons
Expanded dispensary and medical facilities - 60 tons
Evaporators, generators and necessary shore connections - 30 tons