Byzantine Empire 1925...

[TacCovert4]

The guns are powerful, and long ranged, but I would worry about just 4 guns in a long range gunnery duel.  I'd really want more guns than that.  I wonder if you bumped her to 2000t even if you could swing a fifth 140mm mount.  Or cut the Caliber down a bit and get 6+ guns.

[Jefgte]

The guns are powerful, and long ranged, but I would worry about just 4 guns in a long range gunnery duel.  I'd really want more guns than that.  I wonder if you bumped her to 2000t even if you could swing a fifth 140mm mount.  Or cut the Caliber down a bit and get 6+ guns.

16000m for 140/50 and 15000m for 120/45.
Let's say instead that shells are 37kg, not 22kg.

[Jefgte]

Rework with 2M2x140 & 4M2x40 pompom

SD13, Byzantine Empire Super Destroyer laid down 1928

Displacement:
   1 800 t light; 1 895 t standard; 2 229 t normal; 2 496 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (387,13 ft / 383,86 ft) x 36,09 ft x (13,28 / 14,36 ft)
   (118,00 m / 117,00 m) x 11,00 m  x (4,05 / 4,38 m)

Armament:
      4 - 5,51" / 140 mm 50,0 cal guns - 81,99lbs / 37,19kg shells, 220 per gun
     Quick firing guns in deck mounts, 1928 Model
     2 x 2-gun mounts on centreline ends, evenly spread
      8 - 1,57" / 40,0 mm 39,0 cal guns - 1,85lbs / 0,84kg shells, 1 000 per gun
     Anti-air guns in deck mounts, 1928 Model
     4 x 2-gun mounts on sides, evenly spread
      4 raised mounts
      8 - 0,50" / 12,7 mm 62,0 cal guns - 0,07lbs / 0,03kg shells, 6 000 per gun
     Quick firing guns in deck mounts, 1928 Model
     4 x 2-gun mounts on sides, evenly spread
      4 raised mounts
      Weight of broadside 343 lbs / 156 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0,98" / 25 mm         -               -
   2nd:   0,39" / 10 mm         -               -
   3rd:   0,39" / 10 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 41 400 shp / 30 885 Kw = 32,55 kts
   Range 10 400nm at 12,00 kts
   Bunker at max displacement = 601 tons

Complement:
   161 - 210

Cost:
   £0,911 million / $3,644 million

Distribution of weights at normal displacement:
   Armament: 71 tons, 3,2 %
      - Guns: 71 tons, 3,2 %
   Armour: 16 tons, 0,7 %
      - Armament: 16 tons, 0,7 %
   Machinery: 1 114 tons, 50,0 %
   Hull, fittings & equipment: 479 tons, 21,5 %
   Fuel, ammunition & stores: 429 tons, 19,2 %
   Miscellaneous weights: 120 tons, 5,4 %
      - Hull above water: 29 tons
      - On freeboard deck: 60 tons
      - Above deck: 31 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     579 lbs / 262 Kg = 6,9 x 5,5 " / 140 mm shells or 0,3 torpedoes
   Stability (Unstable if below 1.00): 1,27
   Metacentric height 1,7 ft / 0,5 m
   Roll period: 11,7 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0,24
   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): 0,424 / 0,439
   Length to Beam Ratio: 10,64 : 1
   'Natural speed' for length: 19,59 kts
   Power going to wave formation at top speed: 64 %
   Trim (Max stability = 0, Max steadiness = 100): 69
   Bow angle (Positive = bow angles forward): 10,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   18,00 %,  18,54 ft / 5,65 m,  15,58 ft / 4,75 m
      - Forward deck:   33,00 %,  15,58 ft / 4,75 m,  13,12 ft / 4,00 m
      - Aft deck:   33,00 %,  13,12 ft / 4,00 m,  13,12 ft / 4,00 m
      - Quarter deck:   16,00 %,  13,12 ft / 4,00 m,  13,12 ft / 4,00 m
      - Average freeboard:      14,18 ft / 4,32 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 172,5 %
      - Above water (accommodation/working, high = better): 140,8 %
   Waterplane Area: 8 661 Square feet or 805 Square metres
   Displacement factor (Displacement / loading): 77 %
   Structure weight / hull surface area: 33 lbs/sq ft or 160 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,50
      - Longitudinal: 1,22
      - Overall: 0,54
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

6t for 1924 top mast rangefinder
25t for LR marconi

32t for 2x4TTx533HW
30t reserved for new material, armament, minen

15t for improved Hydrophone
5t for 50x90DC
9t for climatisation

Trial speed: 33kts
Bonus: 0.45

[Kaiser Kirk]

"Long range" is a relative thing.

Somewhere in the rule set, probably gun research, is a statement to the effect that the CM of the gun is equal to the KM of shell spotting range.

We know that smaller guns were not viewed as useful at longer ranges for a number of reasons.
What exactly those limits are, is probably not possible to find out.

We do know that DDs were not effective at longer ranges as they were lively vessels- seakeeping being relative, that their masttops / rangefinders and so sightlines were shorter, and also that shell splashes from smaller shells are hard to spot at longer ranges.

So the shell spotting range limit is meant to give everyone a easy to figure and firm baseline to go off.

[Jefgte]

6x120 are better than 4x140

D13, Byzantine Empire Long range D12 laid down 1928

Displacement:
   1 720 t light; 1 801 t standard; 2 146 t normal; 2 422 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (379,73 ft / 374,02 ft) x 36,09 ft x (13,74 / 14,90 ft)
   (115,74 m / 114,00 m) x 11,00 m  x (4,19 / 4,54 m)

Armament:
      6 - 4,72" / 120 mm 45,0 cal guns - 50,00lbs / 22,68kg shells, 200 per gun
     Quick firing guns in deck mounts, 1928 Model
     3 x Twin mounts on centreline ends, majority aft
      1 raised mount aft - superfiring
      4 - 1,57" / 40,0 mm 39,0 cal guns - 2,01lbs / 0,91kg shells, 1 000 per gun
     Anti-air guns in deck mounts, 1928 Model
     2 x 2-gun mounts on sides, forward deck aft
      2 raised mounts
      4 - 0,50" / 12,7 mm 62,0 cal guns - 0,07lbs / 0,03kg shells, 4 000 per gun
     Machine guns in deck mounts, 1928 Model
     2 x 2-gun mounts on sides, forward deck centre
      2 raised mounts
      Weight of broadside 308 lbs / 140 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0,79" / 20 mm         -               -
   2nd:   0,39" / 10 mm         -               -
   4th:   0,39" / 10 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 39 500 shp / 29 467 Kw = 32,32 kts
   Range 11 000nm at 12,00 kts
   Bunker at max displacement = 621 tons

Complement:
   156 - 204

Cost:
   £0,863 million / $3,453 million

Distribution of weights at normal displacement:
   Armament: 48 tons, 2,2 %
      - Guns: 48 tons, 2,2 %
   Armour: 8 tons, 0,4 %
      - Armament: 8 tons, 0,4 %
   Machinery: 1 072 tons, 50,0 %
   Hull, fittings & equipment: 480 tons, 22,4 %
   Fuel, ammunition & stores: 426 tons, 19,9 %
   Miscellaneous weights: 111 tons, 5,2 %
      - Hull above water: 8 tons
      - On freeboard deck: 73 tons
      - Above deck: 30 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     570 lbs / 258 Kg = 10,8 x 4,7 " / 120 mm shells or 0,3 torpedoes
   Stability (Unstable if below 1.00): 1,28
   Metacentric height 1,7 ft / 0,5 m
   Roll period: 11,7 seconds
   Steadiness   - As gun platform (Average = 50 %): 72 %
         - Recoil effect (Restricted arc if above 1.00): 0,24
   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): 0,405 / 0,422
   Length to Beam Ratio: 10,36 : 1
   'Natural speed' for length: 19,34 kts
   Power going to wave formation at top speed: 63 %
   Trim (Max stability = 0, Max steadiness = 100): 69
   Bow angle (Positive = bow angles forward): 15,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   17,50 %,  21,33 ft / 6,50 m,  16,73 ft / 5,10 m
      - Forward deck:   33,50 %,  16,73 ft / 5,10 m,  12,47 ft / 3,80 m
      - Aft deck:   33,50 %,  12,47 ft / 3,80 m,  11,81 ft / 3,60 m
      - Quarter deck:   15,50 %,  11,81 ft / 3,60 m,  12,14 ft / 3,70 m
      - Average freeboard:      14,06 ft / 4,29 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 169,8 %
      - Above water (accommodation/working, high = better): 136,0 %
   Waterplane Area: 8 333 Square feet or 774 Square metres
   Displacement factor (Displacement / loading): 79 %
   Structure weight / hull surface area: 33 lbs/sq ft or 160 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,50
      - Longitudinal: 1,28
      - Overall: 0,54
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

AD
5t for 1924 top mast rangefinder
25t for LR marconi
OD
36t for 2x4TTx533HW
15t for improved Hydrophone
5t for 50x90DC
17t reserved for new material, armament, minen.
AW
8T for climatisation

5610nm@16kts
Trial speed: 33kts
Bonus: 0.68

[TacCovert4]

I would concur that 6 x 120 are the superior option.  I'm running 6 x 130 on my best gunfight dd.   And I'm going to aim for 8 main guns again once I get towards dual purpose guns

[Kaiser Kirk]

At least with the Seekrieg chart, there are progressively lower chances to hit at long range, so  loss of the spotting penalty really hurts at range.

When you add in the ship size modifier , and speed modifiers, ships like DDs become very hard to hit at longer ranges...especially if they aren't broadside.

Overall 6x 12cm should mean you hit sooner (more shots at same hit%).
Also in SK, having taken damage the prior turn impairs a ships's ability to fire back (vibration, concussion, smoke, etc)
So getting shells on target and then continuing to hit each turn has a value.
So I think the more shells 12cm > fewer 14cm

One area we do not greatly consider is the difficulty of handling the heavier shells on a livelier platform like a DD.
The German Zerstorers with 15cm were noted as being difficult, as well as the additional forecastle weight being a problem,
but I believe the handling problem is noted for smaller rounds as well.

I never intended on having 13cm and 12cm, but I'm using 13cm only on my heavier ships.

[Jefgte]

Update range to 12000nm@12 kts.

D13, Byzantine Empire Long range D12 laid down 1928

Displacement:
   1 800 t light; 1 884 t standard; 2 273 t normal; 2 585 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (383,05 ft / 377,30 ft) x 36,09 ft x (14,43 / 15,73 ft)
   (116,76 m / 115,00 m) x 11,00 m  x (4,40 / 4,79 m)

Armament:
      6 - 4,72" / 120 mm 45,0 cal guns - 50,00lbs / 22,68kg shells, 200 per gun
     Quick firing guns in deck mounts, 1928 Model
     3 x Twin mounts on centreline ends, majority forward
      1 raised mount - superfiring
      4 - 1,57" / 40,0 mm 39,0 cal guns - 2,01lbs / 0,91kg shells, 1 000 per gun
     Anti-air guns in deck mounts, 1928 Model
     2 x 2-gun mounts on sides, forward deck aft
      2 raised mounts
      4 - 0,50" / 12,7 mm 62,0 cal guns - 0,07lbs / 0,03kg shells, 4 000 per gun
     Machine guns in deck mounts, 1928 Model
     2 x 2-gun mounts on sides, forward deck centre
      2 raised mounts
      Weight of broadside 308 lbs / 140 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0,79" / 20 mm         -               -
   2nd:   0,39" / 10 mm         -               -
   4th:   0,39" / 10 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 41 100 shp / 30 660 Kw = 32,39 kts
   Range 12 000nm at 12,00 kts
   Bunker at max displacement = 701 tons

Complement:
   164 - 214

Cost:
   £0,908 million / $3,633 million

Distribution of weights at normal displacement:
   Armament: 48 tons, 2,1 %
      - Guns: 48 tons, 2,1 %
   Armour: 8 tons, 0,4 %
      - Armament: 8 tons, 0,4 %
   Machinery: 1 136 tons, 50,0 %
   Hull, fittings & equipment: 498 tons, 21,9 %
   Fuel, ammunition & stores: 474 tons, 20,8 %
   Miscellaneous weights: 109 tons, 4,8 %
      - Hull above water: 8 tons
      - On freeboard deck: 71 tons
      - Above deck: 30 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     598 lbs / 271 Kg = 11,4 x 4,7 " / 120 mm shells or 0,3 torpedoes
   Stability (Unstable if below 1.00): 1,30
   Metacentric height 1,7 ft / 0,5 m
   Roll period: 11,5 seconds
   Steadiness   - As gun platform (Average = 50 %): 72 %
         - Recoil effect (Restricted arc if above 1.00): 0,23
   Seaboat quality  (Average = 1.00): 1,06

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0,405 / 0,423
   Length to Beam Ratio: 10,45 : 1
   'Natural speed' for length: 19,42 kts
   Power going to wave formation at top speed: 63 %
   Trim (Max stability = 0, Max steadiness = 100): 68
   Bow angle (Positive = bow angles forward): 15,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   17,50 %,  21,49 ft / 6,55 m,  16,90 ft / 5,15 m
      - Forward deck:   33,50 %,  16,90 ft / 5,15 m,  12,63 ft / 3,85 m
      - Aft deck:   33,50 %,  12,63 ft / 3,85 m,  11,81 ft / 3,60 m
      - Quarter deck:   15,50 %,  11,81 ft / 3,60 m,  12,14 ft / 3,70 m
      - Average freeboard:      14,17 ft / 4,32 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 169,4 %
      - Above water (accommodation/working, high = better): 131,7 %
   Waterplane Area: 8 406 Square feet or 781 Square metres
   Displacement factor (Displacement / loading): 80 %
   Structure weight / hull surface area: 33 lbs/sq ft or 161 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,50
      - Longitudinal: 1,31
      - Overall: 0,55
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

AD
5t for 1924 top mast rangefinder
25t for LR marconi
OD
36t for 2x4TTx533HW
15t for improved Hydrophone
5t for 50x90DC
15t reserved for new material, armament, minen.
AW
8T for climatisation

6120nm@16kts
Trial speed: 33kts
Bonus: 0.61

[Kaiser Kirk]

Nice ship.
Bigger than my Babr IIs, better armed as well - at least for now. I can swap out the 118mm how for another 120.
But if I see a whole of these running around it might be time to retire the Vakharz II design,
1928 + 10.8month build + 6 month sea trials.. I should start seeing these in 1929.5
Probably will not be in large numbers for a while after that.

[Jefgte]

All Navies have 1600t, even 1800t and 2000t.
Switching the 1500t Palang to 3T2x120 instead of 4T1x120 will only cost 100t more.

[Kaiser Kirk]

True, I can simply field a larger destroyer,
but overall I'm trying to keep hull sizes down
so I can field a larger number of quality ships.
The Babrs have 5x 120 +118HOW, so are close.
They can be rearmed / built with 6x120 if needed,
and are already 1500t.

Part of the consideration is also that these ships
operate in squadrons and have defined roles.
There  also needs to be will be sufficient numbers
to screen the fleet vs. attacking DDs.

Putting numbers and roles first means the
lowest tonnage that can do those is important. 

BUT...if all the Byzantine DDs are large with 6x120,
then the role will include matching them,
and I'll have to ditch the Wolf/Vakharz 1100t ships
for the Palang/Babr 1500s....or bring out a 2000.

[Jefgte]

...Putting numbers and roles first means the
lowest tonnage that can do those is important...

I have the same problem with the 4000t (3T2x191 - 27kts).
I won't be able to build them...too big.
I have to reduce to 3000t with 3T2x152 - 29kts.

[TacCovert4]

I have the same issue.   For now,  I have a 1500t class and a 2000t class of DD.  Once I pick up 2500t DDs, I'll make a heavy DD leader and still make a 1500t range general purpose DD.

[The Rock Doctor]

My planning says I need about 160 destroyers to do what I want, so I'm in the same situation.

[Kaiser Kirk]

I want a home fleet, expeditionary fleet, Pacific Fleet and Atlantic Fleet.
I then want some detached formations.

For the Pacific and Expeditionary, I want longer range DDs the 'Oceanic' or 'Corvettes'...at 1500.
For the Home fleet I want double the base number, but these can be the 'fleet' at 1100.

Fleet Destroyers currently have 3 main roles
- ASW deterrence,
- Screen vs. light combatants (inc incoming planes)
- torpedo attack in conditions that allow me to close.
For cruises, I want destroyers off each flank, and two sets ahead playing 'leapfrog'
to allow sprint & drift. I'd also like a formation in reserve to reinforce/prosecute contacts.
At a minimum I want 3 DDs in each group for triangulation, but optimally 4,
as the 4th would be vectored in by the other 3.

That
So 3-4 in each pod, x 4-5 per each formation x (4+1) Fleets & Home double = 60 to 100 first rate.
For the detached formations, I can live with 4,8,12 or 16...not so worried, and more likely 2nd rate.

Currently I have 9 Babr & 12 Palang Oceanics, and 16 Vakharz & 22 Gurg Fleet Destroyers. Which is 60 first rates.
So I am finally at the bare minimum and building 7 per year to try to close to the desired level.
The little 500 ton Close Escort is meant to possibly replace the reserve formation, being able to to detach to
prosecute contacts.

I have another 72 DDs at 750-1000t for the 2nd rate status, but they generally are screen role vessels.