WesWorld

USS Atlanta, United States Light Cruiser laid down 1936

Displacement:
5,279 t light; 5,601 t standard; 6,349 t normal; 6,947 t full load

Dimensions: Length overall / water x beam x draught
542.77 ft / 530.00 ft x 53.17 ft x 19.00 ft (normal load)
165.44 m / 161.54 m x 16.21 m x 5.79 m

Armament:
12 - 5.00" / 127 mm guns (6x2 guns), 62.50lbs / 28.35kg shells, 1936 Model
Dual purpose guns in deck mounts with hoists
on centreline ends, evenly spread, 4 raised mounts - superfiring
24 - 1.10" / 27.9 mm guns (6x4 guns), 0.67lbs / 0.30kg shells, 1936 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, 2 raised mounts
8 - 0.50" / 12.7 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1936 Model
Machine guns in deck mounts
on side, evenly spread, all raised mounts
Weight of broadside 767 lbs / 348 kg
Shells per gun, main battery: 450
8 - 21.0" / 533.4 mm above water torpedoes

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 4.00" / 102 mm 368.35 ft / 112.27 m 8.75 ft / 2.67 m
Ends: Unarmoured
Main Belt covers 107 % of normal length

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 2.50" / 64 mm 1.00" / 25 mm 2.00" / 51 mm
3rd: 1.00" / 25 mm - -
4th: 0.50" / 13 mm - -

- Armour deck: 1.25" / 32 mm, Conning tower: 2.50" / 64 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 62,156 shp / 46,369 Kw = 33.00 kts
Range 8,500nm at 15.00 kts
Bunker at max displacement = 1,345 tons

Complement:
355 - 462

Cost:
£2.686 million / $10.744 million

Distribution of weights at normal displacement:
Armament: 96 tons, 1.5 %
Armour: 1,035 tons, 16.3 %
- Belts: 529 tons, 8.3 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 67 tons, 1.1 %
- Armour Deck: 420 tons, 6.6 %
- Conning Tower: 18 tons, 0.3 %
Machinery: 1,744 tons, 27.5 %
Hull, fittings & equipment: 2,274 tons, 35.8 %
Fuel, ammunition & stores: 1,070 tons, 16.9 %
Miscellaneous weights: 130 tons, 2.0 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
6,363 lbs / 2,886 Kg = 101.8 x 5.0 " / 127 mm shells or 1.2 torpedoes
Stability (Unstable if below 1.00): 1.13
Metacentric height 2.5 ft / 0.7 m
Roll period: 14.2 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.34
Seaboat quality (Average = 1.00): 1.05

Hull form characteristics:
Hull has rise forward of midbreak
and transom stern
Block coefficient: 0.415
Length to Beam Ratio: 9.97 : 1
'Natural speed' for length: 26.57 kts
Power going to wave formation at top speed: 57 %
Trim (Max stability = 0, Max steadiness = 100): 67
Bow angle (Positive = bow angles forward): 15.00 degrees
Stern overhang: 5.00 ft / 1.52 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 29.00 ft / 8.84 m
- Forecastle (17 %): 21.00 ft / 6.40 m
- Mid (40 %): 21.00 ft / 6.40 m (14.00 ft / 4.27 m aft of break)
- Quarterdeck (14 %): 14.00 ft / 4.27 m
- Stern: 14.00 ft / 4.27 m
- Average freeboard: 17.33 ft / 5.28 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 105.5 %
- Above water (accommodation/working, high = better): 128.4 %
Waterplane Area: 18,175 Square feet or 1,688 Square metres
Displacement factor (Displacement / loading): 117 %
Structure weight / hull surface area: 78 lbs/sq ft or 381 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.86
- Longitudinal: 1.33
- Overall: 0.90
Caution: Hull subject to strain in open-sea
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform

50 tons for radar

80 tons reserved for growth

Looks like a nice enough vessel. Nice large mag.

The BC, while "in bounds" is still a bit on the really skinny side.

Kinda off topic, but I thought a normal space between decks was 8' but you have your break at 7'. Any difference?

Agreed, she IS skinny, but to get the length, beam, etc, to be historical, that's what you end up with. Looking at the historical ship, you definitely think "big destroyer" rather than "cruiser". This version took the historical hull dimensions and lost some depth when it lost the beam 5" mountings.

As to the deck break, I just chose 7'. An 8' break doesn't change anything much, gives a LITTLE more tonnage for some more conning tower armor.

USS Atlanta, United States Light Cruiser laid down 1936

Displacement:
5,279 t light; 5,601 t standard; 6,349 t normal; 6,947 t full load

Dimensions: Length overall / water x beam x draught
542.77 ft / 530.00 ft x 53.17 ft x 19.00 ft (normal load)
165.44 m / 161.54 m x 16.21 m x 5.79 m

Armament:
12 - 5.00" / 127 mm guns (6x2 guns), 62.50lbs / 28.35kg shells, 1936 Model
Dual purpose guns in deck mounts with hoists
on centreline ends, evenly spread, 4 raised mounts - superfiring
24 - 1.10" / 27.9 mm guns (6x4 guns), 0.67lbs / 0.30kg shells, 1936 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, 2 raised mounts
8 - 0.50" / 12.7 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1936 Model
Machine guns in deck mounts
on side, evenly spread, all raised mounts
Weight of broadside 767 lbs / 348 kg
Shells per gun, main battery: 450
12 - 21.0" / 533.4 mm above water torpedoes

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 4.00" / 102 mm 365.70 ft / 111.47 m 8.75 ft / 2.67 m
Ends: Unarmoured
Main Belt covers 106 % of normal length

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 2.50" / 64 mm 1.00" / 25 mm 2.00" / 51 mm
3rd: 1.00" / 25 mm - -
4th: 0.50" / 13 mm - -

- Armour deck: 1.25" / 32 mm, Conning tower: 4.00" / 102 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 62,156 shp / 46,369 Kw = 33.00 kts
Range 8,500nm at 15.00 kts
Bunker at max displacement = 1,345 tons

Complement:
355 - 462

Cost:
£2.686 million / $10.744 million

Distribution of weights at normal displacement:
Armament: 96 tons, 1.5 %
Armour: 1,043 tons, 16.4 %
- Belts: 525 tons, 8.3 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 67 tons, 1.1 %
- Armour Deck: 420 tons, 6.6 %
- Conning Tower: 30 tons, 0.5 %
Machinery: 1,744 tons, 27.5 %
Hull, fittings & equipment: 2,266 tons, 35.7 %
Fuel, ammunition & stores: 1,070 tons, 16.9 %
Miscellaneous weights: 130 tons, 2.0 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
6,306 lbs / 2,860 Kg = 100.9 x 5.0 " / 127 mm shells or 1.2 torpedoes
Stability (Unstable if below 1.00): 1.13
Metacentric height 2.5 ft / 0.7 m
Roll period: 14.3 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.34
Seaboat quality (Average = 1.00): 1.04

Hull form characteristics:
Hull has rise forward of midbreak
and transom stern
Block coefficient: 0.415
Length to Beam Ratio: 9.97 : 1
'Natural speed' for length: 26.57 kts
Power going to wave formation at top speed: 57 %
Trim (Max stability = 0, Max steadiness = 100): 67
Bow angle (Positive = bow angles forward): 15.00 degrees
Stern overhang: 5.00 ft / 1.52 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 29.00 ft / 8.84 m
- Forecastle (17 %): 21.50 ft / 6.55 m
- Mid (40 %): 21.50 ft / 6.55 m (13.50 ft / 4.11 m aft of break)
- Quarterdeck (14 %): 13.50 ft / 4.11 m
- Stern: 13.50 ft / 4.11 m
- Average freeboard: 17.21 ft / 5.25 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 105.5 %
- Above water (accommodation/working, high = better): 111.4 %
Waterplane Area: 18,175 Square feet or 1,688 Square metres
Displacement factor (Displacement / loading): 117 %
Structure weight / hull surface area: 78 lbs/sq ft or 380 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.86
- Longitudinal: 1.32
- Overall: 0.90
Caution: Hull subject to strain in open-sea
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is adequate
Ship has slow, easy roll, a good, steady gun platform

50 tons for radar

80 tons reserved for growth

I thought I was already a bit on the low side with the 0.456 for the Rina Inbaasu CLs...
BTW, why did it lose the beam 5" mountings?

How would you rate this one against the RSAN Dione? The latter was build to the full 1,00 HS standards which makes quite a difference.

Should you game these two which one would you bet one and why?

Probably Roger can run a duel through his programm/Set of rules?

Quoted

Originally posted by Rooijen10
I thought I was already a bit on the low side with the 0.456 for the Rina Inbaasu CLs...
BTW, why did it lose the beam 5" mountings?

Why did it lose the beam 5" mountings? Mostly to allow the size of the ship to be shrunk a bit, the WW US not being the industrial powerhouse it was historically. I thought about trying a 10-gun design, essentially a US version of Dido, but haven't yet.

Quoted

Originally posted by HoOmAn
How would you rate this one against the RSAN Dione? The latter was build to the full 1,00 HS standards which makes quite a difference.

Should you game these two which one would you bet one and why?

Probably Roger can run a duel through his programm/Set of rules?

Well, the Atlanta has 50% more guns of nearly the same size, better armor, and a little more speed, while Dione can (because it's built to 1.0 standards) take more punishment. The major difference in a fight between the two that I can see is that Atlanta has over twice as much ammunition, which means that it can keep fighting longer. Atlanta also has torpedoes (useful in a night or bad weather action, less so during the day), and radar, which Dione doesn't.