ARA El Plata
[ARA Los Andes sunk 2/4/35]
El Plata Class Argentina Gunboat laid down 1932
Displacement:
493 t light; 542 t standard; 592 t normal; 633 t full load
Dimensions: Length overall / water x beam x draught
209.16 ft / 206.04 ft x 27.89 ft x 8.69 ft (normal load)
63.75 m / 62.80 m x 8.50 m x 2.65 m
Armament:
4 - 6.10" / 155 mm guns (2x2 guns), 97.00lbs / 44.00kg shells, 1932 Model
Breech loading guns in deck mounts
on centreline ends, evenly spread
3 - 2.95" / 75.0 mm guns in single mounts, 13.66lbs / 6.20kg shells, 1932 Model
Breech loading guns in deck mounts
on side, all amidships, all raised mounts - superfiring
2 - 1.46" / 37.0 mm guns in single mounts, 1.55lbs / 0.70kg shells, 1932 Model
Anti-aircraft guns in deck mounts
on side, all amidships
2 - 0.79" / 20.0 mm guns in single mounts, 0.24lbs / 0.11kg shells, 1932 Model
Anti-aircraft guns in deck mounts
on side, all forward
6 - 0.51" / 13.0 mm guns in single mounts, 0.07lbs / 0.03kg shells, 1932 Model
Machine guns in deck mounts
on side, evenly spread, 2 raised mounts
Weight of broadside 433 lbs / 196 kg
Shells per gun, main battery: 150
Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 2.76" / 70 mm 1.18" / 30 mm -
2nd: 1.18" / 30 mm 0.59" / 15 mm -
3rd: 0.59" / 15 mm - -
4th: 0.39" / 10 mm - -
5th: 0.39" / 10 mm - -
- Conning tower: 5.91" / 150 mm
Machinery:
Diesel Internal combustion motors,
Geared drive, 2 shafts, 1,500 shp / 1,119 Kw = 16.28 kts
Range 3,500nm at 12.00 kts
Bunker at max displacement = 91 tons
Complement:
59 - 78
Cost:
£0.341 million / $1.364 million
Distribution of weights at normal displacement:
Armament: 62 tons, 10.5 %
Armour: 43 tons, 7.3 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 35 tons, 5.8 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 9 tons, 1.5 %
Machinery: 40 tons, 6.7 %
Hull, fittings & equipment: 307 tons, 51.8 %
Fuel, ammunition & stores: 100 tons, 16.9 %
Miscellaneous weights: 40 tons, 6.8 %
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
812 lbs / 368 Kg = 7.1 x 6.1 " / 155 mm shells or 0.5 torpedoes
Stability (Unstable if below 1.00): 1.29
Metacentric height 1.2 ft / 0.4 m
Roll period: 10.9 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.65
Seaboat quality (Average = 1.00): 2.00
Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.415
Length to Beam Ratio: 7.39 : 1
'Natural speed' for length: 14.35 kts
Power going to wave formation at top speed: 47 %
Trim (Max stability = 0, Max steadiness = 100): 25
Bow angle (Positive = bow angles forward): 10.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 17.72 ft / 5.40 m
- Forecastle (15 %): 17.06 ft / 5.20 m
- Mid (35 %): 17.06 ft / 5.20 m (8.20 ft / 2.50 m aft of break)
- Quarterdeck (18 %): 8.20 ft / 2.50 m
- Stern: 8.20 ft / 2.50 m
- Average freeboard: 11.34 ft / 3.46 m
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 108.9 %
- Above water (accommodation/working, high = better): 125.0 %
Waterplane Area: 3,570 Square feet or 332 Square metres
Displacement factor (Displacement / loading): 89 %
Structure weight / hull surface area: 47 lbs/sq ft or 228 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.83
- Longitudinal: 5.21
- Overall: 1.00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent
Excellent seaboat, comfortable, can fire her guns in the heaviest weather