Refit of the
San Pietro, San Sylvestro & San Gregorio Magno
Cost: 6660 tons per ship
Time: 11.16 months per ship (Just under four quarters)
Modifications: Replacement of Anti-Aircraft batteries with modern 76mm, 37mm, and 25mm weaponry. Addition of modern electronic sensors and other miscellaneous equipment. Removal of floatplane facilities. New 86,000SHP engines lighter then the originals. New horizontal and vertical protection layout. New bow for improved seakeeping.
San Pietro (refit), Italian Armored Cruiser laid down 1933 (Engine 1944)
Displacement:
13,320 t light; 13,990 t standard; 16,585 t normal; 18,661 t full load
Dimensions: Length overall / water x beam x draught
639.76 ft / 623.36 ft x 65.62 ft (Bulges 75.69 ft) x 24.61 ft (normal load)
195.00 m / 190.00 m x 20.00 m (Bulges 23.07 m) x 7.50 m
Armament:
12 - 7.99" / 203 mm guns (4x3 guns), 291.01lbs / 132.00kg shells, 1933 Model
Breech loading guns in turrets (on barbettes)
on centreline ends, evenly spread, 2 raised mounts - superfiring
20 - 2.99" / 76.0 mm guns (10x2 guns), 14.86lbs / 6.74kg shells, 1944 Model
Automatic rapid fire guns in deck mounts with hoists
on side, all amidships, 4 raised mounts - superfiring
12 - 1.46" / 37.0 mm guns (4x3 guns), 1.55lbs / 0.70kg shells, 1944 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
12 - 0.98" / 25.0 mm guns in single mounts, 0.48lbs / 0.22kg shells, 1944 Model
Machine guns in deck mounts
on side, evenly spread
Weight of broadside 3,814 lbs / 1,730 kg
Shells per gun, main battery: 155
Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 5.91" / 150 mm 385.50 ft / 117.50 m 11.48 ft / 3.50 m
Ends: Unarmoured
Main Belt covers 95 % of normal length
- Torpedo Bulkhead and Bulges:
1.57" / 40 mm 305.12 ft / 93.00 m 32.81 ft / 10.00 m
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 7.48" / 190 mm 4.92" / 125 mm 5.91" / 150 mm
2nd: 1.18" / 30 mm 0.79" / 20 mm 0.79" / 20 mm
3rd: 0.39" / 10 mm 0.39" / 10 mm -
4th: 0.39" / 10 mm - -
- Armour deck: 3.54" / 90 mm, Conning tower: 2.76" / 70 mm
Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 86,000 shp / 64,156 Kw = 30.87 kts
Range 9,500nm at 20.00 kts
Bunker at max displacement = 4,671 tons
Complement:
729 - 949
Cost:
£5.349 million / $21.397 million
Distribution of weights at normal displacement:
Armament: 426 tons, 2.6 %
Armour: 4,425 tons, 26.7 %
- Belts: 1,102 tons, 6.6 %
- Torpedo bulkhead: 583 tons, 3.5 %
- Armament: 843 tons, 5.1 %
- Armour Deck: 1,858 tons, 11.2 %
- Conning Tower: 39 tons, 0.2 %
Machinery: 2,196 tons, 13.2 %
Hull, fittings & equipment: 5,948 tons, 35.9 %
Fuel, ammunition & stores: 3,265 tons, 19.7 %
Miscellaneous weights: 325 tons, 2.0 %
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
26,052 lbs / 11,817 Kg = 102.1 x 8.0 " / 203 mm shells or 4.6 torpedoes
Stability (Unstable if below 1.00): 1.15
Metacentric height 3.5 ft / 1.1 m
Roll period: 17.1 seconds
Steadiness - As gun platform (Average = 50 %): 57 %
- Recoil effect (Restricted arc if above 1.00): 0.44
Seaboat quality (Average = 1.00): 1.02
Hull form characteristics:
Hull has rise forward of midbreak
and transom stern
Block coefficient: 0.500
Length to Beam Ratio: 8.24 : 1
'Natural speed' for length: 28.95 kts
Power going to wave formation at top speed: 56 %
Trim (Max stability = 0, Max steadiness = 100): 56
Bow angle (Positive = bow angles forward): 23.50 degrees
Stern overhang: 3.28 ft / 1.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 30.18 ft / 9.20 m
- Forecastle (20 %): 21.98 ft / 6.70 m
- Mid (60 %): 21.98 ft / 6.70 m (13.78 ft / 4.20 m aft of break)
- Quarterdeck (20 %): 13.78 ft / 4.20 m
- Stern: 13.78 ft / 4.20 m
- Average freeboard: 19.36 ft / 5.90 m
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 95.1 %
- Above water (accommodation/working, high = better): 142.5 %
Waterplane Area: 28,340 Square feet or 2,633 Square metres
Displacement factor (Displacement / loading): 132 %
Structure weight / hull surface area: 130 lbs/sq ft or 637 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.97
- Longitudinal: 1.28
- Overall: 1.00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent