For investigating the Filipinos' new Back 40.
How does it look?
(the 6" turret comes off the stockpile)
PRS Pacifica, Filipino Polar Exploration Ship, laid down 1928
Displacement:
8,232 t light; 8,474 t standard; 10,766 t normal; 12,600 t full load
Dimensions: Length overall / water x beam x draught
498.69 ft / 498.69 ft x 88.58 ft x 13.12 ft (normal load)
152.00 m / 152.00 m x 27.00 m x 4.00 m
Air Group:
4 seaplanes
1 catapult, forwards
Armament:
2 - 6.00" / 152 mm guns (1x2 guns), 108.00lbs / 48.99kg shells, 1921 Model
Quick firing guns in a turret (on a barbette)
on centreline aft
2 - 3.94" / 100 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1928 Model
Quick firing guns in deck mounts with hoists
on side, all forward
6 - 2.24" / 57.0 mm guns in single mounts, 6.00lbs / 2.72kg shells, 1928 Model
Dual purpose guns in deck mounts
on side, evenly spread
3 - 0.98" / 25.0 mm guns (1x3 guns), 0.57lbs / 0.26kg shells, 1928 Model
Anti-aircraft guns in a deck mount
on centreline aft, all raised guns - superfiring
8 - 0.54" / 13.7 mm guns (4x2 guns), 0.11lbs / 0.05kg shells, 1928 Model
Machine guns in deck mounts
on side, evenly spread, all raised mounts
Weight of broadside 319 lbs / 145 kg
Shells per gun, main battery: 135
Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 2.95" / 75 mm 328.08 ft / 100.00 m 11.29 ft / 3.44 m
Ends: 3.94" / 100 mm 170.60 ft / 52.00 m 11.29 ft / 3.44 m
Main Belt covers 101 % of normal length
- Torpedo Bulkhead:
1.97" / 50 mm 498.69 ft / 152.00 m 12.60 ft / 3.84 m
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 4.00" / 102 mm 2.00" / 51 mm 1.97" / 50 mm
2nd: 1.18" / 30 mm - 0.79" / 20 mm
3rd: 0.98" / 25 mm - -
4th: 0.59" / 15 mm - -
- Conning tower: 2.56" / 65 mm
Machinery:
Diesel Internal combustion generators,
Electric motors, 4 shafts, 18,160 shp / 13,547 Kw = 20.00 kts
Range 15,000nm at 15.00 kts (Bunkerage = 4,126 tons)
Complement:
528 - 687
Cost:
£1.528 million / $6.111 million
Distribution of weights at normal displacement:
Armament: 39 tons, 0.4 %
Armour: 1,302 tons, 12.1 %
- Belts: 766 tons, 7.1 %
- Torpedo bulkhead: 458 tons, 4.3 %
- Armament: 51 tons, 0.5 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 27 tons, 0.2 %
Machinery: 565 tons, 5.3 %
Hull, fittings & equipment: 5,326 tons, 49.5 %
Fuel, ammunition & stores: 2,534 tons, 23.5 %
Miscellaneous weights: 1,000 tons, 9.3 %
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
39,424 lbs / 17,882 Kg = 365.0 x 6.0 " / 152 mm shells or 10.3 torpedoes
Stability (Unstable if below 1.00): 1.52
Metacentric height 8.5 ft / 2.6 m
Roll period: 12.8 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.01
Seaboat quality (Average = 1.00): 1.24
Hull form characteristics:
Hull has a flush deck
Block coefficient: 0.650
Length to Beam Ratio: 5.63 : 1
'Natural speed' for length: 22.33 kts
Power going to wave formation at top speed: 43 %
Trim (Max stability = 0, Max steadiness = 100): 57
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: 24.61 ft / 7.50 m
- Forecastle (20 %): 16.40 ft / 5.00 m
- Mid (50 %): 15.58 ft / 4.75 m
- Quarterdeck (15 %): 15.58 ft / 4.75 m
- Stern: 15.58 ft / 4.75 m
- Average freeboard: 16.53 ft / 5.04 m
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 40.7 %
- Above water (accommodation/working, high = better): 192.6 %
Waterplane Area: 33,841 Square feet or 3,144 Square metres
Displacement factor (Displacement / loading): 287 %
Structure weight / hull surface area: 132 lbs/sq ft or 646 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.47
- Longitudinal: 1.37
- Overall: 1.40
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
Good seaboat, rides out heavy weather easily
250t for aircraft + one catapult
750t for scientific crew + equipment