WesWorld

San Marco, Italy Cruiser laid down 1943

Displacement:
11,538 t light; 12,099 t standard; 13,498 t normal; 14,618 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(580.92 ft / 570.00 ft) x 69.00 ft x (21.00 / 22.40 ft)
(177.06 m / 173.74 m) x 21.03 m x (6.40 / 6.83 m)

Armament:
12 - 8.00" / 203 mm 45.0 cal guns - 258.18lbs / 117.11kg shells, 150 per gun
Breech loading guns in turret on barbette mounts, 1943 Model
4 x Twin mounts on centreline ends, evenly spread
2 raised mounts - superfiring
2 x Twin mounts on centreline ends, evenly spread
2 double raised mounts
6 - 4.00" / 102 mm 45.0 cal guns - 32.27lbs / 14.64kg shells, 250 per gun
Breech loading guns in deck mounts, 1943 Model
6 x Single mounts on sides, evenly spread
2 raised mounts
36 - 1.00" / 25.4 mm 45.0 cal guns - 0.50lbs / 0.23kg shells, 500 per gun
Breech loading guns in deck mounts, 1943 Model
8 x Quad mounts on sides, evenly spread
2 raised mounts
1 x Quad mount layout not set
1 raised mount
Weight of broadside 3,310 lbs / 1,501 kg
Main Torpedoes
4 - 21.0" / 533 mm, 26.00 ft / 7.92 m torpedoes - 1.746 t each, 6.983 t total
In 2 sets of deck mounted carriage/fixed tubes

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 4.00" / 102 mm 390.00 ft / 118.87 m 18.00 ft / 5.49 m
Ends: Unarmoured
Main Belt covers 105 % of normal length

- Torpedo Bulkhead - Strengthened structural bulkheads:
2.00" / 51 mm 400.00 ft / 121.92 m 40.00 ft / 12.19 m
Beam between torpedo bulkheads 60.00 ft / 18.29 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 8.00" / 203 mm 4.00" / 102 mm 4.00" / 102 mm
2nd: 2.00" / 51 mm 1.00" / 25 mm -
3rd: 1.00" / 25 mm - -

- Protected deck - single deck:
For and Aft decks: 1.00" / 25 mm
Forecastle: 0.50" / 13 mm Quarter deck: 0.50" / 13 mm

Machinery:
Oil fired boilers, steam turbines,
Hydraulic drive, 2 shafts, 110,628 shp / 82,529 Kw = 32.00 kts
Range 5,000nm at 20.00 kts
Bunker at max displacement = 2,519 tons

Complement:
625 - 813

Cost:
£7.236 million / $28.944 million

Distribution of weights at normal displacement:
Armament: 737 tons, 5.5 %
- Guns: 729 tons, 5.4 %
- Weapons: 9 tons, 0.1 %
Armour: 3,743 tons, 27.7 %
- Belts: 1,171 tons, 8.7 %
- Torpedo bulkhead: 1,184 tons, 8.8 %
- Armament: 914 tons, 6.8 %
- Armour Deck: 474 tons, 3.5 %
Machinery: 2,857 tons, 21.2 %
Hull, fittings & equipment: 4,176 tons, 30.9 %
Fuel, ammunition & stores: 1,960 tons, 14.5 %
Miscellaneous weights: 25 tons, 0.2 %
- Above deck: 25 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
19,239 lbs / 8,727 Kg = 75.2 x 8.0 " / 203 mm shells or 2.3 torpedoes
Stability (Unstable if below 1.00): 1.12
Metacentric height 3.6 ft / 1.1 m
Roll period: 15.3 seconds
Steadiness - As gun platform (Average = 50 %): 52 %
- Recoil effect (Restricted arc if above 1.00): 0.73
Seaboat quality (Average = 1.00): 1.04

Hull form characteristics:
Hull has a flush deck,
a normal bow and a cruiser stern
Block coefficient (normal/deep): 0.572 / 0.581
Length to Beam Ratio: 8.26 : 1
'Natural speed' for length: 23.87 kts
Power going to wave formation at top speed: 62 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 20.00 degrees
Stern overhang: -5.00 ft / -1.52 m
Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 20.00 %, 30.00 ft / 9.14 m, 24.00 ft / 7.32 m
- Forward deck: 30.00 %, 24.00 ft / 7.32 m, 24.00 ft / 7.32 m
- Aft deck: 35.00 %, 24.00 ft / 7.32 m, 24.00 ft / 7.32 m
- Quarter deck: 15.00 %, 24.00 ft / 7.32 m, 24.00 ft / 7.32 m
- Average freeboard: 24.48 ft / 7.46 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 103.6 %
- Above water (accommodation/working, high = better): 203.6 %
Waterplane Area: 28,021 Square feet or 2,603 Square metres
Displacement factor (Displacement / loading): 109 %
Structure weight / hull surface area: 128 lbs/sq ft or 623 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.93
- Longitudinal: 1.89
- Overall: 1.00
Adequate machinery, storage, compartmentation space
Excellent accommodation and workspace room



Ships in class expected: 2-3?

My thoughts and suggestions;

Overall it looks a bit archaic for 1942, it looks more like a 1922 ship from the picture (of course drawings can be easily altered so that's no big problem). What is the odd midships beam extension for?
Why the six twin turrets? Four triples would save weight, space and topweight.
Italy tends to use metric measurements for its guns, so 100mm etc rather than 4in etc. Italy in the past used a 203mm 7.99in main gun, before rampining up to a 305mm 12.1in gun.
Generally the AA outfit seems inferior to the kinds of Italian LAA we've become used to and there are no intermediate LAA calibre guns at all.
Having four 4in bunched forward may not be the best layout, and why only four torpedo tubes or why any for that matter?
Speed and range look good.
The armour seems inferior than the last 8in CAs Italy designed, 1in thick decks on a CA is practically useless and the main blet is probably too high. This ship would weigh more with adeqaute deck armour, that is why I would use four triples and thicken the decks to get a better balance overall.

Generally for me the San Pietro design of 1931 seems a superior (if slightly more expensive) design overall. I think this is a good effort but it just lacks the finesse of a well-thought out design and seems to have too many flaws. I think you've made a concious effort to build a CA butreally these kinds of ships demand more to spent on them to make them worthwhile. Not only that but CAs (IMHO) are dead in WW. Not really much point in building more unless it can take and dish out serious punishment. Give me a squadron of decent 12-gun 6in CLs anytime.

Quick comments:
- We've decided to stick with SS2 for Wesworld, at least for the moment, rather than upgrading to the incomplete SS3.
- You might want to check the Italian calibers currently in use, particularly as they're in metric rather than English. Italy uses 100mm and 47mm, as an example.

I'm not all sold on the balance between armour and firepower. For myself, I'd suggest dropping one of the turrets (if not two) and upgrading the deck armour and adding more secondary guns. I'd also drop the TDS armour, since a heavy cruiser doesn't have the beam necessary to provide sufficient depth to the defense. So I think the TDS is just robbing a lot of weight from other things while adding very little to the ship's protection.

Just my two cents, of course.

Thanks for the feedback!

I agree with the points you both made on reflection and I've hopefully made a start on amending them and have almost finished re-writing the SS report in SS2. Regarding the AA suite though, I'm not quite sure I understand what you mean?

Quoted

Originally posted by Rodondo
Thanks for the feedback!

I agree with the points you both made on reflection and I've hopefully made a start on amending them and have almost finished re-writing the SS report in SS2. Regarding the AA suite though, I'm not quite sure I understand what you mean?

In regards to the antiaircraft suite, I suspect that the comment was directed to the light scale of AA defense. For 1943, six heavy AA guns and two dozen or so autocannon is quite light, given the expected weight of air attack. Italy, for one, seems to have been in the forefront of heavier AA defense.

As to the caliber of the guns, the standard Italian calibers for antiaircraft have been 100mm for heavy AA guns, 47mm for a medium-caliber AA gun and 25mm for autocannon for close-in defense. Switching to a 4-in/102mm gun would seem to be counter-productive.

I thought it wasn't too light I guess that 8 100mm guns is light but the 48 25mm guns accompanying them seems to be fairly substantial, though I was planning on upping it to ~64 25mm guns

Would 8-12 100mm guns, and ~12 47mm suffice?

Quoted

Originally posted by Rodondo
I thought it wasn't too light I guess that 8 100mm guns is light but the 48 25mm guns accompanying them seems to be fairly substantial, though I was planning on upping it to ~64 25mm guns

Would 8-12 100mm guns, and ~12 47mm suffice?

Well the last CA, not counting the 12" Super CA's, had 8 100mm and 28 47mm on a 190x20x7.5 13000t hull.

Quoted

Originally posted by Rodondo
I thought it wasn't too light I guess that 8 100mm guns is light but the 48 25mm guns accompanying them seems to be fairly substantial, though I was planning on upping it to ~64 25mm guns

Would 8-12 100mm guns, and ~12 47mm suffice?

A ship's antiaircraft defense is like an onion, there are several layers, but no one layer should be that much thicker than the others. Now what does this mean?

A 100mm AA gun can engage targets at long range, and track them as they close. It has the longest opportunity to hit the target, but, because of size and other contraints, a ship cannot carry that many. Four medium guns bearing on any quarter might be considered a minimum to engage targets before they drop their ordnance.

A medium gun like the 47mm fires faster, but doesn't have the range of the 100mm; it's engagement envelope is shorter in time, but it's ROF is generally higher.

An autocannon like the 25mm has a very high ROF, and is small enough to be stuck all over a ship, but it's range is very short and the time of its target engagement brief indeed. It is the last ditch weapon that throws up a wall of lead that hopefully kills an enemy aircraft.

A good defense will have all three, and, by 1943, should have some sort of radar fire control for at least the heaviest AA guns.