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21

Thursday, April 2nd 2020, 9:51pm

Good points, especially #2 (- Recoil effect (Restricted arc if above 1.00): 0,92). This is an easy stat to overlook as we as springsharp users tend to look at stability, seakeeping and hull strength. My guess is that your length to beam ratio is right at 11:1, which makes it a VERY narrow hull, is the cause. You may have to add more beam and/or cut weight, preferably to bring that length to beam ratio down closer to 10:1.


Good point Wes. I'd also suggest considering increasing the draft of the design, but all those numbers need to balance out, perhaps by trial and error.

22

Thursday, April 2nd 2020, 10:19pm

Okay, now the recoil should be a bit better:

Nemea Class, Kingdom of Greece Destroyer laid down 1949

Displacement:
2.064 t light; 2.186 t standard; 2.438 t normal; 2.640 t full load

Dimensions: Length overall / water x beam x draught
351,05 ft / 347,77 ft x 32,48 ft x 16,08 ft (normal load)
107,00 m / 106,00 m x 9,90 m x 4,90 m

Armament:
8 - 4,72" / 120 mm guns (4x2 guns), 52,72lbs / 23,91kg shells, 1949 Model
Automatic rapid fire guns in deck mounts with hoists
on centreline ends, evenly spread
4 - 1,57" / 40,0 mm guns in single mounts, 1,95lbs / 0,88kg shells, 1949 Model
Anti-aircraft guns in deck mounts
on side, all amidships
12 - 0,79" / 20,0 mm guns (6x2 guns), 0,24lbs / 0,11kg shells, 1949 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
Weight of broadside 432 lbs / 196 kg
Shells per gun, main battery: 300
6 - 23,0" / 584,2 mm above water torpedoes

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1,18" / 30 mm 0,04" / 1 mm 0,39" / 10 mm
2nd: 0,59" / 15 mm - -
3rd: 0,39" / 10 mm - -

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 54.063 shp / 40.331 Kw = 33,50 kts
Range 4.500nm at 16,00 kts
Bunker at max displacement = 454 tons

Complement:
173 - 225

Cost:
£2,163 million / $8,652 million

Distribution of weights at normal displacement:
Armament: 65 tons, 2,6 %
Armour: 12 tons, 0,5 %
- Belts: 0 tons, 0,0 %
- Torpedo bulkhead: 0 tons, 0,0 %
- Armament: 12 tons, 0,5 %
- Armour Deck: 0 tons, 0,0 %
- Conning Tower: 0 tons, 0,0 %
Machinery: 1.120 tons, 45,9 %
Hull, fittings & equipment: 711 tons, 29,2 %
Fuel, ammunition & stores: 375 tons, 15,4 %
Miscellaneous weights: 157 tons, 6,4 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
626 lbs / 284 Kg = 11,9 x 4,7 " / 120 mm shells or 0,3 torpedoes
Stability (Unstable if below 1.00): 1,16
Metacentric height 1,2 ft / 0,4 m
Roll period: 12,4 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0,85
Seaboat quality (Average = 1.00): 1,11

Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0,470
Length to Beam Ratio: 10,71 : 1
'Natural speed' for length: 18,65 kts
Power going to wave formation at top speed: 69 %
Trim (Max stability = 0, Max steadiness = 100): 45
Bow angle (Positive = bow angles forward): 0,00 degrees
Stern overhang: 3,28 ft / 1,00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 21,33 ft / 6,50 m
- Forecastle (20 %): 19,69 ft / 6,00 m
- Mid (50 %): 19,69 ft / 6,00 m (16,40 ft / 5,00 m aft of break)
- Quarterdeck (15 %): 13,12 ft / 4,00 m
- Stern: 13,12 ft / 4,00 m
- Average freeboard: 17,11 ft / 5,22 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 176,7 %
- Above water (accommodation/working, high = better): 77,1 %
Waterplane Area: 7.328 Square feet or 681 Square metres
Displacement factor (Displacement / loading): 74 %
Structure weight / hull surface area: 39 lbs/sq ft or 190 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0,50
- Longitudinal: 3,44
- Overall: 0,61
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is cramped

Electronics (45 tons)
HVAC (12 tons)
LRASM Modele 1947 2x4 32cm launchers and reloads (15 tons)
Crew confort (85 tons)

Electronics:
DRBV-9 surface and air search radar (1 radar, 7.5 tons)
DRBI-3 sentry radar (1 radar, 7.5 tons)
DRBN-1 navigational surface and air search radar (1 radar, 2 tons)
DRBC-4 (DRBC-3B is ascceptable) fire-control radar (2 radars, 8 tons)
ARBR-1 radar jammer/detector (2 units, 2 tons)
SAGEM HF/DF (3 tons)

23

Thursday, April 2nd 2020, 10:52pm

I guess what I'm feeling about the design is that it tries to load quite a lot of guns and equipment into a very small hull.

The closest Russian equivalent of this design, at least in terms of size, is the 1944-dated Soobrazitelny class. That uses only 4x130mm (and 2x75mm) on slightly less tonnage and similar dimensions. The closest French equivalents are the Jaguar - Saber - Cimeterre class, with 6x100mm on a similar hull and displacement. The 1949 Russian and French destroyers are significantly larger (2,500t light displacement) yet still only have 6x130mm guns.

Springsharp doesn't necessarily measure these things, but given the specs, I'm going to guess that topweight is probably a major issue, as well as deck space.

24

Friday, April 3rd 2020, 2:00am

Sorry for not anwer I am a bit sick (with none fever luckly)

I reduce the guns

Nemea Class, Kingdom of Greece Destroyer laid down 1949

Displacement:
2.082 t light; 2.186 t standard; 2.438 t normal; 2.640 t full load

Dimensions: Length overall / water x beam x draught
351,05 ft / 347,77 ft x 32,48 ft x 16,08 ft (normal load)
107,00 m / 106,00 m x 9,90 m x 4,90 m

Armament:
6 - 4,72" / 120 mm guns (3x2 guns), 52,72lbs / 23,91kg shells, 1949 Model
Automatic rapid fire guns in deck mounts with hoists
on centreline ends, majority forward
4 - 1,57" / 40,0 mm guns in single mounts, 1,95lbs / 0,88kg shells, 1949 Model
Anti-aircraft guns in deck mounts
on side, all amidships
12 - 0,79" / 20,0 mm guns (6x2 guns), 0,24lbs / 0,11kg shells, 1949 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
Weight of broadside 327 lbs / 148 kg
Shells per gun, main battery: 300
6 - 23,0" / 584,2 mm above water torpedoes

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1,18" / 30 mm 0,04" / 1 mm 0,39" / 10 mm
2nd: 0,59" / 15 mm - -
3rd: 0,39" / 10 mm - -

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 54.063 shp / 40.331 Kw = 33,50 kts
Range 4.500nm at 16,00 kts
Bunker at max displacement = 454 tons

Complement:
173 - 225

Cost:
£2,091 million / $8,364 million

Distribution of weights at normal displacement:
Armament: 49 tons, 2,0 %
Armour: 9 tons, 0,4 %
- Belts: 0 tons, 0,0 %
- Torpedo bulkhead: 0 tons, 0,0 %
- Armament: 9 tons, 0,4 %
- Armour Deck: 0 tons, 0,0 %
- Conning Tower: 0 tons, 0,0 %
Machinery: 1.143 tons, 46,9 %
Hull, fittings & equipment: 724 tons, 29,7 %
Fuel, ammunition & stores: 357 tons, 14,6 %
Miscellaneous weights: 157 tons, 6,4 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
677 lbs / 307 Kg = 12,8 x 4,7 " / 120 mm shells or 0,3 torpedoes
Stability (Unstable if below 1.00): 1,17
Metacentric height 1,2 ft / 0,4 m
Roll period: 12,2 seconds
Steadiness - As gun platform (Average = 50 %): 51 %
- Recoil effect (Restricted arc if above 1.00): 0,64
Seaboat quality (Average = 1.00): 1,13

Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0,470
Length to Beam Ratio: 10,71 : 1
'Natural speed' for length: 18,65 kts
Power going to wave formation at top speed: 69 %
Trim (Max stability = 0, Max steadiness = 100): 45
Bow angle (Positive = bow angles forward): 0,00 degrees
Stern overhang: 3,28 ft / 1,00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 21,33 ft / 6,50 m
- Forecastle (20 %): 19,69 ft / 6,00 m
- Mid (50 %): 19,69 ft / 6,00 m (16,40 ft / 5,00 m aft of break)
- Quarterdeck (15 %): 13,12 ft / 4,00 m
- Stern: 13,12 ft / 4,00 m
- Average freeboard: 17,11 ft / 5,22 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 174,6 %
- Above water (accommodation/working, high = better): 77,1 %
Waterplane Area: 7.328 Square feet or 681 Square metres
Displacement factor (Displacement / loading): 77 %
Structure weight / hull surface area: 40 lbs/sq ft or 193 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0,52
- Longitudinal: 3,60
- Overall: 0,63
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is cramped

Electronics (45 tons)
HVAC (12 tons)
LRASM Modele 1947 2x4 32cm launchers and reloads (15 tons)
Crew confort (85 tons)

Electronics:
DRBV-9 surface and air search radar (1 radar, 7.5 tons)
DRBI-3 sentry radar (1 radar, 7.5 tons)
DRBN-1 navigational surface and air search radar (1 radar, 2 tons)
DRBC-4 (DRBC-3B is ascceptable) fire-control radar (2 radars, 8 tons)
ARBR-1 radar jammer/detector (2 units, 2 tons)
SAGEM HF/DF (3 tons)

25

Yesterday, 6:39am

Now this is a refit. The original is this one. i just changed the guns to automatics and reduced the range to make every thing fit.


Ares Class, Kingdom of Greece Light Cruiser laid down 1940


Displacement:
8.643 t light; 9.176 t standard; 10.178 t normal; 10.980 t full load


Dimensions: Length overall / water x beam x draught
570,00 ft / 557,00 ft x 62,00 ft x 19,50 ft (normal load)
173,73 m / 169,77 m x 18,90 m x 5,94 m


Armament:

12 - 6,00" / 152 mm guns (4x3 guns), 108,00lbs / 48,99kg shells, 1949 Model
Automatic rapid fire guns in turrets (on barbettes)
on centreline ends, evenly spread
8 - 5,00" / 127 mm guns (4x2 guns), 62,50lbs / 28,35kg shells, 1940 Model
Dual purpose guns in deck mounts with hoists
on side, all amidships
16 - 1,57" / 39,9 mm guns (4x4 guns), 1,93lbs / 0,88kg shells, 1940 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
8 - 1,57" / 39,9 mm guns (2x4 guns), 1,93lbs / 0,88kg shells, 1940 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
8 - 0,98" / 24,9 mm guns (4x2 guns), 0,47lbs / 0,21kg shells, 1940 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
Weight of broadside 1.846 lbs / 837 kg
Shells per gun, main battery: 300
8 - 24,0" / 609,6 mm above water torpedoes


Armour:

- Belts: Width (max) Length (avg) Height (avg)
Main: 4,00" / 102 mm 362,00 ft / 110,34 m 11,45 ft / 3,49 m
Ends: Unarmoured
Main Belt covers 100 % of normal length
Main belt does not fully cover magazines and engineering spaces


- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 4,00" / 102 mm 1,00" / 25 mm 2,00" / 51 mm
2nd: 2,00" / 51 mm 0,50" / 13 mm 1,00" / 25 mm
3rd: 0,38" / 10 mm - -
4th: 0,38" / 10 mm - -
5th: 0,50" / 13 mm - -


- Armour deck: 2,00" / 51 mm, Conning tower: 3,00" / 76 mm



Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 93.034 shp / 69.403 Kw = 32,22 kts
Range 7.245nm at 16,00 kts
Bunker at max displacement = 1.803 tons



Complement:
506 - 658


Cost:
£5,231 million / $20,924 million





Distribution of weights at normal displacement:
Armament: 263 tons, 2,6 %
Armour: 1.827 tons, 17,9 %
- Belts: 698 tons, 6,9 %
- Torpedo bulkhead: 0 tons, 0,0 %
- Armament: 224 tons, 2,2 %
- Armour Deck: 874 tons, 8,6 %
- Conning Tower: 30 tons, 0,3 %
Machinery: 2.488 tons, 24,4 %
Hull, fittings & equipment: 3.916 tons, 38,5 %
Fuel, ammunition & stores: 1.535 tons, 15,1 %
Miscellaneous weights: 150 tons, 1,5 %



Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
12.026 lbs / 5.455 Kg = 111,4 x 6,0 " / 152 mm shells or 1,5 torpedoes
Stability (Unstable if below 1.00): 1,12
Metacentric height 3,0 ft / 0,9 m
Roll period: 15,0 seconds
Steadiness - As gun platform (Average = 50 %): 69 %
- Recoil effect (Restricted arc if above 1.00): 0,47
Seaboat quality (Average = 1.00): 1,07




Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0,529
Length to Beam Ratio: 8,98 : 1
'Natural speed' for length: 23,60 kts
Power going to wave formation at top speed: 60 %
Trim (Max stability = 0, Max steadiness = 100): 65
Bow angle (Positive = bow angles forward): 20,00 degrees
Stern overhang: 2,44 ft / 0,74 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 29,00 ft / 8,84 m
- Forecastle (20 %): 25,00 ft / 7,62 m
- Mid (50 %): 25,00 ft / 7,62 m (17,00 ft / 5,18 m aft of break)
- Quarterdeck (15 %): 17,00 ft / 5,18 m
- Stern: 17,00 ft / 5,18 m
- Average freeboard: 21,32 ft / 6,50 m




Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 102,7 %
- Above water (accommodation/working, high = better): 145,7 %
Waterplane Area: 23.633 Square feet or 2.196 Square metres
Displacement factor (Displacement / loading): 112 %
Structure weight / hull surface area: 103 lbs/sq ft or 505 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0,94
- Longitudinal: 1,65
- Overall: 1,00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent

26

Yesterday, 7:10am

First and foremost I'm certain this refit would be incredibly costly and in my opinion unnecessary given the capabilities of this design. Given that you have 5" DP guns, the size difference between them and the main armament of 6" guns wouldn't justify the cost to make them auto. At any rate replacing the standard 6" guns with an auto design would require a complete redesign of the turret and its handling equipment, 6" shells are just too large to handle with manpower alone. Five inch guns are at the limit at which a man can lift shells with his bare hands for a prolonged period of time, any larger and rate of fire would slow due to crew fatigue. Redesign of the turret would require most likely a larger turret which your barbette may not be able to handle.

On that note I think it would be easier to exchange the triple 6" turrets for twin 7.48" but again you would have to change the shell hoists and modify the magazines for larger shells and more propellant, which again would be very costly. You could consider removing a triple 6" turret aft and add a larger AA gun, something like a 2.95" auto/AA, and reduce the 40mm outfit slightly. Some would argue that having 75mm and 40mm guns is having too many caliber's in the same size range, or it complicates the ships logistics having to carry so many different types of shells, so its worth considering standardizing your AA armament to a larger caliber rather than having a hodge podge of various guns.

There is another option (that would also be costly) and that is to replace the triple 6" turrets with twin auto 6" turrets. You would still have to replace shell handling equipment and add new turrets but the space should be there in the barbettes and Magazine space might (emphasis on might) be adequate.

27

Yesterday, 9:07am

Yes. Maybe I am being to greedy. Is just that I look at all the possibilities and go crazy. In other point I may regret of the gun change but the ship is going to see other minor refits. I will start to be more carefull to my desisions because I have the felling that I am taking decitions too fast about some things.

P.S.: I am in bed so If can't publish the update version.

28

Yesterday, 7:49pm

I'll echo Wes's comments.

Perhaps I can offer a bit of a reality check by addressing the mathematics. I'm not sure which 6" gun the Greeks used in 1940, but I suspect it's either a licensed or exported variant of the British 6"/50 Mark XXIII gun. That's already a pretty good gun for this period, with 6-8 rounds per minute. The necessary automation during this era will add in around 50% as much weight as a standard breech-loading gun. Therefore, you'd end up with two barrels instead of three.

That means, in order to justify the change, your 6" auto needs to reliably fire twelve rounds per minute in order to break even, compared to your previous breech-loader.

If you can only equal your previous rate of fire, then you'll spend a significant amount of money to develop an extremely complicated bit of machinery (that will probably break the moment you need it most)...

29

Yesterday, 9:12pm

Its also worth noting several things about this design as is. First 12x6" is nothing to sneeze at, its still a decent armament vs destroyers and other light cruisers even if you remove 1 triple turret to beef up the AA.
Its got decent speed and armor, overall comparable to the historical Southampton class cruisers. They are only 7 years old so other than the worlds navies moving towards auto loading guns she hasn't been rendered obsolete by design advancements, far from it. With light refits to upgrade her AA capabilities and her electronics these two ships will still provide excellent service for the Greeks.